first commit

system/src/Grav/Framework/Cache/AbstractCache.php

@@ -0,0 +1,30 @@
+<?php
+/**
+ * @package    Grav\Framework\Cache
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Cache;
+
+use Grav\Framework\Cache\Exception\InvalidArgumentException;
+
+/**
+ * Cache trait for PSR-16 compatible "Simple Cache" implementation
+ * @package Grav\Framework\Cache
+ */
+abstract class AbstractCache implements CacheInterface
+{
+    use CacheTrait;
+
+    /**
+     * @param string $namespace
+     * @param null|int|\DateInterval $defaultLifetime
+     * @throws InvalidArgumentException
+     */
+    public function __construct($namespace = '', $defaultLifetime = null)
+    {
+        $this->init($namespace, $defaultLifetime);
+    }
+}

system/src/Grav/Framework/Cache/Adapter/ChainCache.php

@@ -0,0 +1,197 @@
+<?php
+/**
+ * @package    Grav\Framework\Cache
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Cache\Adapter;
+
+use Grav\Framework\Cache\AbstractCache;
+use Grav\Framework\Cache\CacheInterface;
+use Grav\Framework\Cache\Exception\InvalidArgumentException;
+
+/**
+ * Cache class for PSR-16 compatible "Simple Cache" implementation using chained cache adapters.
+ *
+ * @package Grav\Framework\Cache
+ */
+class ChainCache extends AbstractCache
+{
+    /**
+     * @var array|CacheInterface[]
+     */
+    protected $caches;
+
+    /**
+     * @var int
+     */
+    protected $count;
+
+    /**
+     * Chain Cache constructor.
+     * @param array $caches
+     * @param null|int|\DateInterval $defaultLifetime
+     * @throws \Psr\SimpleCache\InvalidArgumentException
+     */
+    public function __construct(array $caches, $defaultLifetime = null)
+    {
+        parent::__construct('', $defaultLifetime);
+
+        if (!$caches) {
+            throw new InvalidArgumentException('At least one cache must be specified');
+        }
+
+        foreach ($caches as $cache) {
+            if (!$cache instanceof CacheInterface) {
+                throw new InvalidArgumentException(
+                    sprintf(
+                        "The class '%s' does not implement the '%s' interface",
+                        get_class($cache),
+                        CacheInterface::class
+                    )
+                );
+            }
+        }
+
+        $this->caches = array_values($caches);
+        $this->count = count($caches);
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function doGet($key, $miss)
+    {
+        foreach ($this->caches as $i => $cache) {
+            $value = $cache->doGet($key, $miss);
+            if ($value !== $miss) {
+                while (--$i >= 0) {
+                    // Update all the previous caches with missing value.
+                    $this->caches[$i]->doSet($key, $value, $this->getDefaultLifetime());
+                }
+
+                return $value;
+            }
+        }
+
+        return $miss;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function doSet($key, $value, $ttl)
+    {
+        $success = true;
+        $i = $this->count;
+
+        while ($i--) {
+            $success = $this->caches[$i]->doSet($key, $value, $ttl) && $success;
+        }
+
+        return $success;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function doDelete($key)
+    {
+        $success = true;
+        $i = $this->count;
+
+        while ($i--) {
+            $success = $this->caches[$i]->doDelete($key) && $success;
+        }
+
+        return $success;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function doClear()
+    {
+        $success = true;
+        $i = $this->count;
+
+        while ($i--) {
+            $success = $this->caches[$i]->doClear() && $success;
+        }
+        return $success;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function doGetMultiple($keys, $miss)
+    {
+        $list = [];
+        foreach ($this->caches as $i => $cache) {
+            $list[$i] = $cache->doGetMultiple($keys, $miss);
+
+            $keys = array_diff_key($keys, $list[$i]);
+
+            if (!$keys) {
+                break;
+            }
+        }
+
+        $values = [];
+        // Update all the previous caches with missing values.
+        foreach (array_reverse($list) as $i => $items) {
+            $values += $items;
+            if ($i && $values) {
+                $this->caches[$i-1]->doSetMultiple($values, $this->getDefaultLifetime());
+            }
+        }
+
+        return $values;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function doSetMultiple($values, $ttl)
+    {
+        $success = true;
+        $i = $this->count;
+
+        while ($i--) {
+            $success = $this->caches[$i]->doSetMultiple($values, $ttl) && $success;
+        }
+
+        return $success;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function doDeleteMultiple($keys)
+    {
+        $success = true;
+        $i = $this->count;
+
+        while ($i--) {
+            $success = $this->caches[$i]->doDeleteMultiple($keys) && $success;
+        }
+
+        return $success;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function doHas($key)
+    {
+        foreach ($this->caches as $cache) {
+            if ($cache->doHas($key)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+}

system/src/Grav/Framework/Cache/Adapter/DoctrineCache.php

@@ -0,0 +1,123 @@
+<?php
+/**
+ * @package    Grav\Framework\Cache
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Cache\Adapter;
+
+use Doctrine\Common\Cache\CacheProvider;
+use Grav\Framework\Cache\AbstractCache;
+use Grav\Framework\Cache\Exception\InvalidArgumentException;
+
+/**
+ * Cache class for PSR-16 compatible "Simple Cache" implementation using Doctrine Cache backend.
+ * @package Grav\Framework\Cache
+ */
+class DoctrineCache extends AbstractCache
+{
+    /**
+     * @var CacheProvider
+     */
+    protected $driver;
+
+    /**
+     * Doctrine Cache constructor.
+     *
+     * @param CacheProvider $doctrineCache
+     * @param string $namespace
+     * @param null|int|\DateInterval $defaultLifetime
+     * @throws \Psr\SimpleCache\InvalidArgumentException
+     */
+    public function __construct(CacheProvider $doctrineCache, $namespace = '', $defaultLifetime = null)
+    {
+        // Do not use $namespace or $defaultLifetime directly, store them with constructor and fetch with methods.
+        parent::__construct($namespace, $defaultLifetime);
+
+        // Set namespace to Doctrine Cache provider if it was given.
+        $namespace = $this->getNamespace();
+        $namespace && $doctrineCache->setNamespace($namespace);
+
+        $this->driver = $doctrineCache;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function doGet($key, $miss)
+    {
+        $value = $this->driver->fetch($key);
+
+        // Doctrine cache does not differentiate between no result and cached 'false'. Make sure that we do.
+        return $value !== false || $this->driver->contains($key) ? $value : $miss;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function doSet($key, $value, $ttl)
+    {
+        return $this->driver->save($key, $value, (int) $ttl);
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function doDelete($key)
+    {
+        return $this->driver->delete($key);
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function doClear()
+    {
+        return $this->driver->deleteAll();
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function doGetMultiple($keys, $miss)
+    {
+        return $this->driver->fetchMultiple($keys);
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function doSetMultiple($values, $ttl)
+    {
+        return $this->driver->saveMultiple($values, (int) $ttl);
+    }
+
+    /**
+     * @inheritdoc
+     * @throws \Psr\SimpleCache\InvalidArgumentException
+     */
+    public function doDeleteMultiple($keys)
+    {
+        // TODO: Remove when Doctrine Cache has been updated to support the feature.
+        if (!method_exists($this->driver, 'deleteMultiple')) {
+            $success = true;
+            foreach ($keys as $key) {
+                $success = $this->delete($key) && $success;
+            }
+
+            return $success;
+        }
+
+        return $this->driver->deleteMultiple($keys);
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function doHas($key)
+    {
+        return $this->driver->contains($key);
+    }
+}

system/src/Grav/Framework/Cache/Adapter/FileCache.php

@@ -0,0 +1,210 @@
+<?php
+/**
+ * @package    Grav\Framework\Cache
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Cache\Adapter;
+
+use Grav\Framework\Cache\AbstractCache;
+use Grav\Framework\Cache\Exception\CacheException;
+use Grav\Framework\Cache\Exception\InvalidArgumentException;
+
+/**
+ * Cache class for PSR-16 compatible "Simple Cache" implementation using file backend.
+ *
+ * Defaults to 1 year TTL. Does not support unlimited TTL.
+ *
+ * @package Grav\Framework\Cache
+ */
+class FileCache extends AbstractCache
+{
+    private $directory;
+    private $tmp;
+
+    /**
+     * @inheritdoc
+     */
+    public function __construct($namespace = '', $defaultLifetime = null)
+    {
+        parent::__construct($namespace, $defaultLifetime ?: 31557600); // = 1 year
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function doGet($key, $miss)
+    {
+        $now = time();
+        $file = $this->getFile($key);
+
+        if (!file_exists($file) || !$h = @fopen($file, 'rb')) {
+            return $miss;
+        }
+
+        if ($now >= (int) $expiresAt = fgets($h)) {
+            fclose($h);
+            @unlink($file);
+        } else {
+            $i = rawurldecode(rtrim(fgets($h)));
+            $value = stream_get_contents($h);
+            fclose($h);
+
+            if ($i === $key) {
+                return unserialize($value);
+            }
+        }
+
+        return $miss;
+    }
+
+    /**
+     * @inheritdoc
+     * @throws \Psr\SimpleCache\CacheException
+     */
+    public function doSet($key, $value, $ttl)
+    {
+        $expiresAt = time() + (int)$ttl;
+
+        $result = $this->write(
+            $this->getFile($key, true),
+            $expiresAt . "\n" . rawurlencode($key) . "\n" . serialize($value),
+            $expiresAt
+        );
+
+        if (!$result && !is_writable($this->directory)) {
+            throw new CacheException(sprintf('Cache directory is not writable (%s)', $this->directory));
+        }
+
+        return $result;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function doDelete($key)
+    {
+        $file = $this->getFile($key);
+
+        return (!file_exists($file) || @unlink($file) || !file_exists($file));
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function doClear()
+    {
+        $result = true;
+        $iterator = new \RecursiveIteratorIterator(new \RecursiveDirectoryIterator($this->directory, \FilesystemIterator::SKIP_DOTS));
+
+        foreach ($iterator as $file) {
+            $result = ($file->isDir() || @unlink($file) || !file_exists($file)) && $result;
+        }
+
+        return $result;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function doHas($key)
+    {
+        $file = $this->getFile($key);
+
+        return file_exists($file) && (@filemtime($file) > time() || $this->doGet($key, null));
+    }
+
+    /**
+     * @param string $key
+     * @param bool $mkdir
+     * @return string
+     */
+    protected function getFile($key, $mkdir = false)
+    {
+        $hash = str_replace('/', '-', base64_encode(hash('sha256', static::class . $key, true)));
+        $dir = $this->directory . $hash[0] . DIRECTORY_SEPARATOR . $hash[1] . DIRECTORY_SEPARATOR;
+
+        if ($mkdir && !file_exists($dir)) {
+            @mkdir($dir, 0777, true);
+        }
+
+        return $dir . substr($hash, 2, 20);
+    }
+
+    /**
+     * @param string $namespace
+     * @param string $directory
+     * @throws \Psr\SimpleCache\InvalidArgumentException
+     */
+    private function init($namespace, $directory)
+    {
+        if (!isset($directory[0])) {
+            $directory = sys_get_temp_dir() . '/grav-cache';
+        } else {
+            $directory = realpath($directory) ?: $directory;
+        }
+
+        if (isset($namespace[0])) {
+            if (preg_match('#[^-+_.A-Za-z0-9]#', $namespace, $match)) {
+                throw new InvalidArgumentException(sprintf('Namespace contains "%s" but only characters in [-+_.A-Za-z0-9] are allowed.', $match[0]));
+            }
+            $directory .= DIRECTORY_SEPARATOR . $namespace;
+        }
+
+        if (!file_exists($directory)) {
+            @mkdir($directory, 0777, true);
+        }
+
+        $directory .= DIRECTORY_SEPARATOR;
+        // On Windows the whole path is limited to 258 chars
+        if ('\\' === DIRECTORY_SEPARATOR && strlen($directory) > 234) {
+            throw new InvalidArgumentException(sprintf('Cache folder is too long (%s)', $directory));
+        }
+        $this->directory = $directory;
+    }
+
+    /**
+     * @param string $file
+     * @param string $data
+     * @param int|null $expiresAt
+     * @return bool
+     */
+    private function write($file, $data, $expiresAt = null)
+    {
+        set_error_handler(__CLASS__.'::throwError');
+
+        try {
+            if ($this->tmp === null) {
+                $this->tmp = $this->directory . uniqid('', true);
+            }
+
+            file_put_contents($this->tmp, $data);
+
+            if ($expiresAt !== null) {
+                touch($this->tmp, $expiresAt);
+            }
+
+            return rename($this->tmp, $file);
+        } finally {
+            restore_error_handler();
+        }
+    }
+
+    /**
+     * @internal
+     * @throws \ErrorException
+     */
+    public static function throwError($type, $message, $file, $line)
+    {
+        throw new \ErrorException($message, 0, $type, $file, $line);
+    }
+
+    public function __destruct()
+    {
+        if ($this->tmp !== null && file_exists($this->tmp)) {
+            unlink($this->tmp);
+        }
+    }
+}

system/src/Grav/Framework/Cache/Adapter/MemoryCache.php

@@ -0,0 +1,61 @@
+<?php
+/**
+ * @package    Grav\Framework\Cache
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Cache\Adapter;
+
+use Grav\Framework\Cache\AbstractCache;
+
+/**
+ * Cache class for PSR-16 compatible "Simple Cache" implementation using in memory backend.
+ *
+ * Memory backend does not use namespace or default ttl as the cache is unique to each cache object and request.
+ *
+ * @package Grav\Framework\Cache
+ */
+class MemoryCache extends AbstractCache
+{
+    /**
+     * @var array
+     */
+    protected $cache = [];
+
+    public function doGet($key, $miss)
+    {
+        if (!array_key_exists($key, $this->cache)) {
+            return $miss;
+        }
+
+        return $this->cache[$key];
+    }
+
+    public function doSet($key, $value, $ttl)
+    {
+        $this->cache[$key] = $value;
+
+        return true;
+    }
+
+    public function doDelete($key)
+    {
+        unset($this->cache[$key]);
+
+        return true;
+    }
+
+    public function doClear()
+    {
+        $this->cache = [];
+
+        return true;
+    }
+
+    public function doHas($key)
+    {
+        return array_key_exists($key, $this->cache);
+    }
+}

system/src/Grav/Framework/Cache/Adapter/SessionCache.php

@@ -0,0 +1,78 @@
+<?php
+/**
+ * @package    Grav\Framework\Cache
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Cache\Adapter;
+
+use Grav\Framework\Cache\AbstractCache;
+
+/**
+ * Cache class for PSR-16 compatible "Simple Cache" implementation using session backend.
+ *
+ * @package Grav\Framework\Cache
+ */
+class SessionCache extends AbstractCache
+{
+    const VALUE = 0;
+    const LIFETIME = 1;
+
+    public function doGet($key, $miss)
+    {
+        $stored = $this->doGetStored($key);
+
+        return $stored ? $stored[self::VALUE] : $miss;
+    }
+
+    public function doSet($key, $value, $ttl)
+    {
+        $stored = [self::VALUE => $value];
+        if (null !== $ttl) {
+            $stored[self::LIFETIME] = time() + $ttl;
+
+        }
+
+        $_SESSION[$this->getNamespace()][$key] = $stored;
+
+        return true;
+    }
+
+    public function doDelete($key)
+    {
+        unset($_SESSION[$this->getNamespace()][$key]);
+
+        return true;
+    }
+
+    public function doClear()
+    {
+        unset($_SESSION[$this->getNamespace()]);
+
+        return true;
+    }
+
+    public function doHas($key)
+    {
+        return $this->doGetStored($key) !== null;
+    }
+
+    public function getNamespace()
+    {
+        return 'cache-' . parent::getNamespace();
+    }
+
+    protected function doGetStored($key)
+    {
+        $stored = isset($_SESSION[$this->getNamespace()][$key]) ? $_SESSION[$this->getNamespace()][$key] : null;
+
+        if (isset($stored[self::LIFETIME]) && $stored[self::LIFETIME] < time()) {
+            unset($_SESSION[$this->getNamespace()][$key]);
+            $stored = null;
+        }
+
+        return $stored ?: null;
+    }
+}

system/src/Grav/Framework/Cache/CacheInterface.php

@@ -0,0 +1,27 @@
+<?php
+/**
+ * @package    Grav\Framework\Cache
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Cache;
+
+use Psr\SimpleCache\CacheInterface as SimpleCacheInterface;
+
+/**
+ * PSR-16 compatible "Simple Cache" interface.
+ * @package Grav\Framework\Object\Storage
+ */
+interface CacheInterface extends SimpleCacheInterface
+{
+    public function doGet($key, $miss);
+    public function doSet($key, $value, $ttl);
+    public function doDelete($key);
+    public function doClear();
+    public function doGetMultiple($keys, $miss);
+    public function doSetMultiple($values, $ttl);
+    public function doDeleteMultiple($keys);
+    public function doHas($key);
+}

system/src/Grav/Framework/Cache/CacheTrait.php

@@ -0,0 +1,341 @@
+<?php
+/**
+ * @package    Grav\Framework\Cache
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Cache;
+
+use Grav\Framework\Cache\Exception\InvalidArgumentException;
+
+/**
+ * Cache trait for PSR-16 compatible "Simple Cache" implementation
+ * @package Grav\Framework\Cache
+ */
+trait CacheTrait
+{
+    /**
+     * @var string
+     */
+    private $namespace = '';
+
+    /**
+     * @var int|null
+     */
+    private $defaultLifetime = null;
+
+    /**
+     * @var \stdClass
+     */
+    private $miss;
+
+    /**
+     * Always call from constructor.
+     *
+     * @param string $namespace
+     * @param null|int|\DateInterval $defaultLifetime
+     * @throws \Psr\SimpleCache\InvalidArgumentException
+     */
+    protected function init($namespace = '', $defaultLifetime = null)
+    {
+        $this->namespace = (string) $namespace;
+        $this->defaultLifetime = $this->convertTtl($defaultLifetime);
+        $this->miss = new \stdClass;
+    }
+
+    /**
+     * @return string
+     */
+    protected function getNamespace()
+    {
+        return $this->namespace;
+    }
+
+    /**
+     * @return int|null
+     */
+    protected function getDefaultLifetime()
+    {
+        return $this->defaultLifetime;
+    }
+
+    /**
+     * @inheritdoc
+     * @throws \Psr\SimpleCache\InvalidArgumentException
+     */
+    public function get($key, $default = null)
+    {
+        $this->validateKey($key);
+
+        $value = $this->doGet($key, $this->miss);
+
+        return $value !== $this->miss ? $value : $default;
+    }
+
+    /**
+     * @inheritdoc
+     * @throws \Psr\SimpleCache\InvalidArgumentException
+     */
+    public function set($key, $value, $ttl = null)
+    {
+        $this->validateKey($key);
+
+        $ttl = $this->convertTtl($ttl);
+
+        // If a negative or zero TTL is provided, the item MUST be deleted from the cache.
+        return null !== $ttl && $ttl <= 0 ? $this->doDelete($key) : $this->doSet($key, $value, $ttl);
+    }
+
+    /**
+     * @inheritdoc
+     * @throws \Psr\SimpleCache\InvalidArgumentException
+     */
+    public function delete($key)
+    {
+        $this->validateKey($key);
+
+        return $this->doDelete($key);
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function clear()
+    {
+        return $this->doClear();
+    }
+
+    /**
+     * @inheritdoc
+     * @throws \Psr\SimpleCache\InvalidArgumentException
+     */
+    public function getMultiple($keys, $default = null)
+    {
+        if ($keys instanceof \Traversable) {
+            $keys = iterator_to_array($keys, false);
+        } elseif (!is_array($keys)) {
+            throw new InvalidArgumentException(
+                sprintf(
+                    'Cache keys must be array or Traversable, "%s" given',
+                    is_object($keys) ? get_class($keys) : gettype($keys)
+                )
+            );
+        }
+
+        if (empty($keys)) {
+            return [];
+        }
+
+        $this->validateKeys($keys);
+        $keys = array_unique($keys);
+        $keys = array_combine($keys, $keys);
+
+        $list = $this->doGetMultiple($keys, $this->miss);
+
+        // Make sure that values are returned in the same order as the keys were given.
+        $values = [];
+        foreach ($keys as $key) {
+            if (!array_key_exists($key, $list) || $list[$key] === $this->miss) {
+                $values[$key] = $default;
+            } else {
+                $values[$key] = $list[$key];
+            }
+        }
+
+        return $values;
+    }
+
+    /**
+     * @inheritdoc
+     * @throws \Psr\SimpleCache\InvalidArgumentException
+     */
+    public function setMultiple($values, $ttl = null)
+    {
+        if ($values instanceof \Traversable) {
+            $values = iterator_to_array($values, true);
+        } elseif (!is_array($values)) {
+            throw new InvalidArgumentException(
+                sprintf(
+                    'Cache values must be array or Traversable, "%s" given',
+                    is_object($values) ? get_class($values) : gettype($values)
+                )
+            );
+        }
+
+        $keys = array_keys($values);
+
+        if (empty($keys)) {
+            return true;
+        }
+
+        $this->validateKeys($keys);
+
+        $ttl = $this->convertTtl($ttl);
+
+        // If a negative or zero TTL is provided, the item MUST be deleted from the cache.
+        return null !== $ttl && $ttl <= 0 ? $this->doDeleteMultiple($keys) : $this->doSetMultiple($values, $ttl);
+    }
+
+    /**
+     * @inheritdoc
+     * @throws \Psr\SimpleCache\InvalidArgumentException
+     */
+    public function deleteMultiple($keys)
+    {
+        if ($keys instanceof \Traversable) {
+            $keys = iterator_to_array($keys, false);
+        } elseif (!is_array($keys)) {
+            throw new InvalidArgumentException(
+                sprintf(
+                    'Cache keys must be array or Traversable, "%s" given',
+                    is_object($keys) ? get_class($keys) : gettype($keys)
+                )
+            );
+        }
+
+        if (empty($keys)) {
+            return true;
+        }
+
+        $this->validateKeys($keys);
+
+        return $this->doDeleteMultiple($keys);
+    }
+
+    /**
+     * @inheritdoc
+     * @throws \Psr\SimpleCache\InvalidArgumentException
+     */
+    public function has($key)
+    {
+        $this->validateKey($key);
+
+        return $this->doHas($key);
+    }
+
+    abstract public function doGet($key, $miss);
+    abstract public function doSet($key, $value, $ttl);
+    abstract public function doDelete($key);
+    abstract public function doClear();
+
+    /**
+     * @param array $keys
+     * @param mixed $miss
+     * @return array
+     */
+    public function doGetMultiple($keys, $miss)
+    {
+        $results = [];
+
+        foreach ($keys as $key) {
+            $value = $this->doGet($key, $miss);
+            if ($value !== $miss) {
+                $results[$key] = $value;
+            }
+        }
+
+        return $results;
+    }
+
+    /**
+     * @param array $values
+     * @param int $ttl
+     * @return bool
+     */
+    public function doSetMultiple($values, $ttl)
+    {
+        $success = true;
+
+        foreach ($values as $key => $value) {
+            $success = $this->doSet($key, $value, $ttl) && $success;
+        }
+
+        return $success;
+    }
+
+    /**
+     * @param array $keys
+     * @return bool
+     */
+    public function doDeleteMultiple($keys)
+    {
+        $success = true;
+
+        foreach ($keys as $key) {
+            $success = $this->doDelete($key) && $success;
+        }
+
+        return $success;
+    }
+
+    abstract public function doHas($key);
+
+    /**
+     * @param string $key
+     * @throws \Psr\SimpleCache\InvalidArgumentException
+     */
+    protected function validateKey($key)
+    {
+        if (!is_string($key)) {
+            throw new InvalidArgumentException(
+                sprintf(
+                    'Cache key must be string, "%s" given',
+                    is_object($key) ? get_class($key) : gettype($key)
+                )
+            );
+        }
+        if (!isset($key[0])) {
+            throw new InvalidArgumentException('Cache key length must be greater than zero');
+        }
+        if (strlen($key) > 64) {
+            throw new InvalidArgumentException(
+                sprintf('Cache key length must be less than 65 characters, key had %s characters', strlen($key))
+            );
+        }
+        if (strpbrk($key, '{}()/\@:') !== false) {
+            throw new InvalidArgumentException(
+                sprintf('Cache key "%s" contains reserved characters {}()/\@:', $key)
+            );
+        }
+    }
+
+    /**
+     * @param array $keys
+     * @throws \Psr\SimpleCache\InvalidArgumentException
+     */
+    protected function validateKeys($keys)
+    {
+        foreach ($keys as $key) {
+            $this->validateKey($key);
+        }
+    }
+
+    /**
+     * @param null|int|\DateInterval    $ttl
+     * @return int|null
+     * @throws \Psr\SimpleCache\InvalidArgumentException
+     */
+    protected function convertTtl($ttl)
+    {
+        if ($ttl === null) {
+            return $this->getDefaultLifetime();
+        }
+
+        if (is_int($ttl)) {
+            return $ttl;
+        }
+
+        if ($ttl instanceof \DateInterval) {
+            $ttl = (int) \DateTime::createFromFormat('U', 0)->add($ttl)->format('U');
+        }
+
+        throw new InvalidArgumentException(
+            sprintf(
+                'Expiration date must be an integer, a DateInterval or null, "%s" given',
+                is_object($ttl) ? get_class($ttl) : gettype($ttl)
+            )
+        );
+    }
+}

system/src/Grav/Framework/Cache/Exception/CacheException.php

@@ -0,0 +1,19 @@
+<?php
+/**
+ * @package    Grav\Framework\Cache
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Cache\Exception;
+
+use Psr\SimpleCache\CacheException as SimpleCacheException;
+
+/**
+ * CacheException class for PSR-16 compatible "Simple Cache" implementation.
+ * @package Grav\Framework\Cache\Exception
+ */
+class CacheException extends \Exception implements SimpleCacheException
+{
+}

system/src/Grav/Framework/Cache/Exception/InvalidArgumentException.php

@@ -0,0 +1,19 @@
+<?php
+/**
+ * @package    Grav\Framework\Cache
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Cache\Exception;
+
+use Psr\SimpleCache\InvalidArgumentException as SimpleCacheInvalidArgumentException;
+
+/**
+ * InvalidArgumentException class for PSR-16 compatible "Simple Cache" implementation.
+ * @package Grav\Framework\Cache\Exception
+ */
+class InvalidArgumentException extends \InvalidArgumentException implements SimpleCacheInvalidArgumentException
+{
+}

system/src/Grav/Framework/Collection/AbstractFileCollection.php

@@ -0,0 +1,227 @@
+<?php
+/**
+ * @package    Grav\Framework\Collection
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Collection;
+
+use Doctrine\Common\Collections\Criteria;
+use Doctrine\Common\Collections\Expr\ClosureExpressionVisitor;
+use Grav\Common\Grav;
+use RocketTheme\Toolbox\ResourceLocator\RecursiveUniformResourceIterator;
+use RocketTheme\Toolbox\ResourceLocator\UniformResourceLocator;
+
+/**
+ * Collection of objects stored into a filesystem.
+ *
+ * @package Grav\Framework\Collection
+ */
+class AbstractFileCollection extends AbstractLazyCollection implements FileCollectionInterface
+{
+    /**
+     * @var string
+     */
+    protected $path;
+
+    /**
+     * @var \RecursiveDirectoryIterator|RecursiveUniformResourceIterator
+     */
+    protected $iterator;
+
+    /**
+     * @var callable
+     */
+    protected $createObjectFunction;
+
+    /**
+     * @var callable
+     */
+    protected $filterFunction;
+
+    /**
+     * @var int
+     */
+    protected $flags;
+
+    /**
+     * @var int
+     */
+    protected $nestingLimit;
+
+    /**
+     * @param string $path
+     */
+    protected function __construct($path)
+    {
+        $this->path = $path;
+        $this->flags = self::INCLUDE_FILES | self::INCLUDE_FOLDERS;
+        $this->nestingLimit = 0;
+        $this->createObjectFunction = [$this, 'createObject'];
+
+        $this->setIterator();
+    }
+
+    /**
+     * @return string
+     */
+    public function getPath()
+    {
+        return $this->path;
+    }
+
+    /**
+     * @param Criteria $criteria
+     * @return ArrayCollection
+     * @todo Implement lazy matching
+     */
+    public function matching(Criteria $criteria)
+    {
+        $expr = $criteria->getWhereExpression();
+
+        $oldFilter = $this->filterFunction;
+        if ($expr) {
+            $visitor = new ClosureExpressionVisitor();
+            $filter = $visitor->dispatch($expr);
+            $this->addFilter($filter);
+        }
+
+        $filtered = $this->doInitializeByIterator($this->iterator, $this->nestingLimit);
+        $this->filterFunction = $oldFilter;
+
+        if ($orderings = $criteria->getOrderings()) {
+            $next = null;
+            foreach (array_reverse($orderings) as $field => $ordering) {
+                $next = ClosureExpressionVisitor::sortByField($field, $ordering == Criteria::DESC ? -1 : 1, $next);
+            }
+
+            uasort($filtered, $next);
+        } else {
+            ksort($filtered);
+        }
+
+        $offset = $criteria->getFirstResult();
+        $length = $criteria->getMaxResults();
+
+        if ($offset || $length) {
+            $filtered = array_slice($filtered, (int)$offset, $length);
+        }
+
+        return new ArrayCollection($filtered);
+    }
+
+    protected function setIterator()
+    {
+        $iteratorFlags = \RecursiveDirectoryIterator::SKIP_DOTS + \FilesystemIterator::UNIX_PATHS
+            + \FilesystemIterator::CURRENT_AS_SELF + \FilesystemIterator::FOLLOW_SYMLINKS;
+
+        if (strpos($this->path, '://')) {
+            /** @var UniformResourceLocator $locator */
+            $locator = Grav::instance()['locator'];
+            $this->iterator = $locator->getRecursiveIterator($this->path, $iteratorFlags);
+        } else {
+            $this->iterator = new \RecursiveDirectoryIterator($this->path, $iteratorFlags);
+        }
+    }
+
+    /**
+     * @param callable $filterFunction
+     * @return $this
+     */
+    protected function addFilter(callable $filterFunction)
+    {
+        if ($this->filterFunction) {
+            $oldFilterFunction = $this->filterFunction;
+            $this->filterFunction = function ($expr) use ($oldFilterFunction, $filterFunction) {
+                return $oldFilterFunction($expr) && $filterFunction($expr);
+            };
+        } else {
+            $this->filterFunction = $filterFunction;
+        }
+
+        return $this;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    protected function doInitialize()
+    {
+        $filtered = $this->doInitializeByIterator($this->iterator, $this->nestingLimit);
+        ksort($filtered);
+
+        $this->collection = new ArrayCollection($filtered);
+    }
+
+    protected function doInitializeByIterator(\SeekableIterator $iterator, $nestingLimit)
+    {
+        $children = [];
+        $objects = [];
+        $filter = $this->filterFunction;
+        $objectFunction = $this->createObjectFunction;
+
+        /** @var \RecursiveDirectoryIterator $file */
+        foreach ($iterator as $file) {
+            // Skip files if they shouldn't be included.
+            if (!($this->flags & static::INCLUDE_FILES) && $file->isFile()) {
+                continue;
+            }
+
+            // Apply main filter.
+            if ($filter && !$filter($file)) {
+                continue;
+            }
+
+            // Include children if the recursive flag is set.
+            if (($this->flags & static::RECURSIVE) && $nestingLimit > 0 && $file->hasChildren()) {
+                $children[] = $file->getChildren();
+            }
+
+            // Skip folders if they shouldn't be included.
+            if (!($this->flags & static::INCLUDE_FOLDERS) && $file->isDir()) {
+                continue;
+            }
+
+            $object = $objectFunction($file);
+            $objects[$object->key] = $object;
+        }
+
+        if ($children) {
+            $objects += $this->doInitializeChildren($children, $nestingLimit - 1);
+        }
+
+        return $objects;
+    }
+
+    /**
+     * @param \RecursiveDirectoryIterator[] $children
+     * @return array
+     */
+    protected function doInitializeChildren(array $children, $nestingLimit)
+    {
+        $objects = [];
+
+        foreach ($children as $iterator) {
+            $objects += $this->doInitializeByIterator($iterator, $nestingLimit);
+        }
+
+        return $objects;
+    }
+
+    /**
+     * @param \RecursiveDirectoryIterator $file
+     * @return object
+     */
+    protected function createObject($file)
+    {
+        return (object) [
+            'key' => $file->getSubPathname(),
+            'type' => $file->isDir() ? 'folder' : 'file:' . $file->getExtension(),
+            'url' => method_exists($file, 'getUrl') ? $file->getUrl() : null,
+            'pathname' => $file->getPathname(),
+            'mtime' => $file->getMTime()
+        ];
+    }
+}

system/src/Grav/Framework/Collection/AbstractLazyCollection.php

@@ -0,0 +1,62 @@
+<?php
+/**
+ * @package    Grav\Framework\Collection
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Collection;
+
+use Doctrine\Common\Collections\AbstractLazyCollection as BaseAbstractLazyCollection;
+
+/**
+ * General JSON serializable collection.
+ *
+ * @package Grav\Framework\Collection
+ */
+abstract class AbstractLazyCollection extends BaseAbstractLazyCollection implements CollectionInterface
+{
+    /**
+     * The backed collection to use
+     *
+     * @var ArrayCollection
+     */
+    protected $collection;
+
+    /**
+     * {@inheritDoc}
+     */
+    public function reverse()
+    {
+        $this->initialize();
+        return $this->collection->reverse();
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function shuffle()
+    {
+        $this->initialize();
+        return $this->collection->shuffle();
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function chunk($size)
+    {
+        $this->initialize();
+        return $this->collection->chunk($size);
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    public function jsonSerialize()
+    {
+        $this->initialize();
+        return $this->collection->jsonSerialize();
+    }
+}

system/src/Grav/Framework/Collection/ArrayCollection.php

@@ -0,0 +1,73 @@
+<?php
+/**
+ * @package    Grav\Framework\Collection
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Collection;
+
+use Doctrine\Common\Collections\ArrayCollection as BaseArrayCollection;
+
+/**
+ * General JSON serializable collection.
+ *
+ * @package Grav\Framework\Collection
+ */
+class ArrayCollection extends BaseArrayCollection implements CollectionInterface
+{
+    /**
+     * Reverse the order of the items.
+     *
+     * @return static
+     */
+    public function reverse()
+    {
+        // TODO: remove when PHP 5.6 is minimum (with doctrine/collections v1.4).
+        if (!method_exists($this, 'createFrom')) {
+            return new static(array_reverse($this->toArray()));
+        }
+
+        return $this->createFrom(array_reverse($this->toArray()));
+    }
+
+    /**
+     * Shuffle items.
+     *
+     * @return static
+     */
+    public function shuffle()
+    {
+        $keys = $this->getKeys();
+        shuffle($keys);
+
+        // TODO: remove when PHP 5.6 is minimum (with doctrine/collections v1.4).
+        if (!method_exists($this, 'createFrom')) {
+            return new static(array_replace(array_flip($keys), $this->toArray()));
+        }
+
+        return $this->createFrom(array_replace(array_flip($keys), $this->toArray()));
+    }
+
+    /**
+     * Split collection into chunks.
+     *
+     * @param int $size     Size of each chunk.
+     * @return array
+     */
+    public function chunk($size)
+    {
+        return array_chunk($this->toArray(), $size, true);
+    }
+
+    /**
+     * Implementes JsonSerializable interface.
+     *
+     * @return array
+     */
+    public function jsonSerialize()
+    {
+        return $this->toArray();
+    }
+}

system/src/Grav/Framework/Collection/CollectionInterface.php

@@ -0,0 +1,41 @@
+<?php
+/**
+ * @package    Grav\Framework\Collection
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Collection;
+
+use Doctrine\Common\Collections\Collection;
+
+/**
+ * Collection Interface.
+ *
+ * @package Grav\Framework\Collection
+ */
+interface CollectionInterface extends Collection, \JsonSerializable
+{
+    /**
+     * Reverse the order of the items.
+     *
+     * @return static
+     */
+    public function reverse();
+
+    /**
+     * Shuffle items.
+     *
+     * @return static
+     */
+    public function shuffle();
+
+    /**
+     * Split collection into chunks.
+     *
+     * @param int $size     Size of each chunk.
+     * @return array
+     */
+    public function chunk($size);
+}

system/src/Grav/Framework/Collection/FileCollection.php

@@ -0,0 +1,93 @@
+<?php
+/**
+ * @package    Grav\Framework\Collection
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Collection;
+
+/**
+ * Collection of objects stored into a filesystem.
+ *
+ * @package Grav\Framework\Collection
+ */
+class FileCollection extends AbstractFileCollection
+{
+    /**
+     * @param string $path
+     * @param int    $flags
+     */
+    public function __construct($path, $flags = null)
+    {
+        parent::__construct($path);
+
+        $this->flags = (int)($flags ?: self::INCLUDE_FILES | self::INCLUDE_FOLDERS | self::RECURSIVE);
+
+        $this->setIterator();
+        $this->setFilter();
+        $this->setObjectBuilder();
+        $this->setNestingLimit();
+    }
+
+    /**
+     * @return int
+     */
+    public function getFlags()
+    {
+        return $this->flags;
+    }
+
+    /**
+     * @return int
+     */
+    public function getNestingLimit()
+    {
+        return $this->nestingLimit;
+    }
+
+    /**
+     * @param int $limit
+     * @return $this
+     */
+    public function setNestingLimit($limit = 99)
+    {
+        $this->nestingLimit = (int) $limit;
+
+        return $this;
+    }
+
+    /**
+     * @param callable|null $filterFunction
+     * @return $this
+     */
+    public function setFilter(callable $filterFunction = null)
+    {
+        $this->filterFunction = $filterFunction;
+
+        return $this;
+    }
+
+    /**
+     * @param callable $filterFunction
+     * @return $this
+     */
+    public function addFilter(callable $filterFunction)
+    {
+        parent::addFilter($filterFunction);
+
+        return $this;
+    }
+
+    /**
+     * @param callable|null $objectFunction
+     * @return $this
+     */
+    public function setObjectBuilder(callable $objectFunction = null)
+    {
+        $this->createObjectFunction = $objectFunction ?: [$this, 'createObject'];
+
+        return $this;
+    }
+}

system/src/Grav/Framework/Collection/FileCollectionInterface.php

@@ -0,0 +1,28 @@
+<?php
+/**
+ * @package    Grav\Framework\Collection
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Collection;
+
+use Doctrine\Common\Collections\Selectable;
+
+/**
+ * Collection of objects stored into a filesystem.
+ *
+ * @package Grav\Framework\Collection
+ */
+interface FileCollectionInterface extends CollectionInterface, Selectable
+{
+    const INCLUDE_FILES = 1;
+    const INCLUDE_FOLDERS = 2;
+    const RECURSIVE = 4;
+
+    /**
+     * @return string
+     */
+    public function getPath();
+}

system/src/Grav/Framework/ContentBlock/ContentBlock.php

@@ -0,0 +1,230 @@
+<?php
+/**
+ * @package    Grav\Framework\ContentBlock
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\ContentBlock;
+
+/**
+ * Class to create nested blocks of content.
+ *
+ * $innerBlock = ContentBlock::create();
+ * $innerBlock->setContent('my inner content');
+ * $outerBlock = ContentBlock::create();
+ * $outerBlock->setContent(sprintf('Inside my outer block I have %s.', $innerBlock->getToken()));
+ * $outerBlock->addBlock($innerBlock);
+ * echo $outerBlock;
+ *
+ * @package Grav\Framework\ContentBlock
+ */
+class ContentBlock implements ContentBlockInterface
+{
+    protected $version = 1;
+    protected $id;
+    protected $tokenTemplate = '@@BLOCK-%s@@';
+    protected $content = '';
+    protected $blocks = [];
+
+    /**
+     * @param string $id
+     * @return static
+     */
+    public static function create($id = null)
+    {
+        return new static($id);
+    }
+
+    /**
+     * @param array $serialized
+     * @return ContentBlockInterface
+     */
+    public static function fromArray(array $serialized)
+    {
+        try {
+            $type = isset($serialized['_type']) ? $serialized['_type'] : null;
+            $id = isset($serialized['id']) ? $serialized['id'] : null;
+
+            if (!$type || !$id || !is_a($type, 'Grav\Framework\ContentBlock\ContentBlockInterface', true)) {
+                throw new \RuntimeException('Bad data');
+            }
+
+            /** @var ContentBlockInterface $instance */
+            $instance = new $type($id);
+            $instance->build($serialized);
+        } catch (\Exception $e) {
+            throw new \RuntimeException(sprintf('Cannot unserialize Block: %s', $e->getMessage()), $e->getCode(), $e);
+        }
+
+        return $instance;
+    }
+
+    /**
+     * Block constructor.
+     *
+     * @param string $id
+     */
+    public function __construct($id = null)
+    {
+        $this->id = $id ? (string) $id : $this->generateId();
+    }
+
+    /**
+     * @return string
+     */
+    public function getId()
+    {
+        return $this->id;
+    }
+
+    /**
+     * @return string
+     */
+    public function getToken()
+    {
+        return sprintf($this->tokenTemplate, $this->getId());
+    }
+
+    /**
+     * @return array
+     */
+    public function toArray()
+    {
+        $blocks = [];
+        /**
+         * @var string $id
+         * @var ContentBlockInterface $block
+         */
+        foreach ($this->blocks as $block) {
+            $blocks[$block->getId()] = $block->toArray();
+        }
+
+        $array = [
+            '_type' => get_class($this),
+            '_version' => $this->version,
+            'id' => $this->id,
+        ];
+
+        if ($this->content) {
+            $array['content'] = $this->content;
+        }
+
+        if ($blocks) {
+            $array['blocks'] = $blocks;
+        }
+
+        return $array;
+    }
+
+    /**
+     * @return string
+     */
+    public function toString()
+    {
+        if (!$this->blocks) {
+            return (string) $this->content;
+        }
+
+        $tokens = [];
+        $replacements = [];
+        foreach ($this->blocks as $block) {
+            $tokens[] = $block->getToken();
+            $replacements[] = $block->toString();
+        }
+
+        return str_replace($tokens, $replacements, (string) $this->content);
+    }
+
+    /**
+     * @return string
+     */
+    public function __toString()
+    {
+        try {
+            return $this->toString();
+        } catch (\Exception $e) {
+            return sprintf('Error while rendering block: %s', $e->getMessage());
+        }
+    }
+
+    /**
+     * @param array $serialized
+     * @throws \RuntimeException
+     */
+    public function build(array $serialized)
+    {
+        $this->checkVersion($serialized);
+
+        $this->id = isset($serialized['id']) ? $serialized['id'] : $this->generateId();
+
+        if (isset($serialized['content'])) {
+            $this->setContent($serialized['content']);
+        }
+
+        $blocks = isset($serialized['blocks']) ? (array) $serialized['blocks'] : [];
+        foreach ($blocks as $block) {
+            $this->addBlock(self::fromArray($block));
+        }
+    }
+
+    /**
+     * @param string $content
+     * @return $this
+     */
+    public function setContent($content)
+    {
+        $this->content = $content;
+
+        return $this;
+    }
+
+    /**
+     * @param ContentBlockInterface $block
+     * @return $this
+     */
+    public function addBlock(ContentBlockInterface $block)
+    {
+        $this->blocks[$block->getId()] = $block;
+
+        return $this;
+    }
+
+    /**
+     * @return string
+     */
+    public function serialize()
+    {
+        return serialize($this->toArray());
+    }
+
+    /**
+     * @param string $serialized
+     */
+    public function unserialize($serialized)
+    {
+        $array = unserialize($serialized);
+        $this->build($array);
+    }
+
+    /**
+     * @return string
+     */
+    protected function generateId()
+    {
+        return uniqid('', true);
+    }
+
+    /**
+     * @param array $serialized
+     * @throws \RuntimeException
+     */
+    protected function checkVersion(array $serialized)
+    {
+        $version = isset($serialized['_version']) ? (string) $serialized['_version'] : '1';
+        if ($version !== $this->version) {
+            throw new \RuntimeException(sprintf('Unsupported version %s', $version));
+        }
+    }
+}

system/src/Grav/Framework/ContentBlock/ContentBlockInterface.php

@@ -0,0 +1,75 @@
+<?php
+/**
+ * @package    Grav\Framework\ContentBlock
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\ContentBlock;
+
+/**
+ * ContentBlock Interface
+ * @package Grav\Framework\ContentBlock
+ */
+interface ContentBlockInterface extends \Serializable
+{
+    /**
+     * @param string $id
+     * @return static
+     */
+    public static function create($id = null);
+
+    /**
+     * @param array $serialized
+     * @return ContentBlockInterface
+     */
+    public static function fromArray(array $serialized);
+
+    /**
+     * @param string $id
+     */
+    public function __construct($id = null);
+
+    /**
+     * @return string
+     */
+    public function getId();
+
+    /**
+     * @return string
+     */
+    public function getToken();
+
+    /**
+     * @return array
+     */
+    public function toArray();
+
+    /**
+     * @return string
+     */
+    public function toString();
+
+    /**
+     * @return string
+     */
+    public function __toString();
+
+    /**
+     * @param array $serialized
+     */
+    public function build(array $serialized);
+
+    /**
+     * @param string $content
+     * @return $this
+     */
+    public function setContent($content);
+
+    /**
+     * @param ContentBlockInterface $block
+     * @return $this
+     */
+    public function addBlock(ContentBlockInterface $block);
+}

system/src/Grav/Framework/ContentBlock/HtmlBlock.php

@@ -0,0 +1,385 @@
+<?php
+/**
+ * @package    Grav\Framework\ContentBlock
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\ContentBlock;
+
+/**
+ * HtmlBlock
+ *
+ * @package Grav\Framework\ContentBlock
+ */
+class HtmlBlock extends ContentBlock implements HtmlBlockInterface
+{
+    protected $frameworks = [];
+    protected $styles = [];
+    protected $scripts = [];
+    protected $html = [];
+
+    /**
+     * @return array
+     */
+    public function getAssets()
+    {
+        $assets = $this->getAssetsFast();
+
+        $this->sortAssets($assets['styles']);
+        $this->sortAssets($assets['scripts']);
+        $this->sortAssets($assets['html']);
+
+        return $assets;
+    }
+
+    /**
+     * @return array
+     */
+    public function getFrameworks()
+    {
+        $assets = $this->getAssetsFast();
+
+        return array_keys($assets['frameworks']);
+    }
+
+    /**
+     * @param string $location
+     * @return array
+     */
+    public function getStyles($location = 'head')
+    {
+        return $this->getAssetsInLocation('styles', $location);
+    }
+
+    /**
+     * @param string $location
+     * @return array
+     */
+    public function getScripts($location = 'head')
+    {
+        return $this->getAssetsInLocation('scripts', $location);
+    }
+
+    /**
+     * @param string $location
+     * @return array
+     */
+    public function getHtml($location = 'bottom')
+    {
+        return $this->getAssetsInLocation('html', $location);
+    }
+
+    /**
+     * @return array[]
+     */
+    public function toArray()
+    {
+        $array = parent::toArray();
+
+        if ($this->frameworks) {
+            $array['frameworks'] = $this->frameworks;
+        }
+        if ($this->styles) {
+            $array['styles'] = $this->styles;
+        }
+        if ($this->scripts) {
+            $array['scripts'] = $this->scripts;
+        }
+        if ($this->html) {
+            $array['html'] = $this->html;
+        }
+
+        return $array;
+    }
+
+    /**
+     * @param array $serialized
+     * @throws \RuntimeException
+     */
+    public function build(array $serialized)
+    {
+        parent::build($serialized);
+
+        $this->frameworks = isset($serialized['frameworks']) ? (array) $serialized['frameworks'] : [];
+        $this->styles = isset($serialized['styles']) ? (array) $serialized['styles'] : [];
+        $this->scripts = isset($serialized['scripts']) ? (array) $serialized['scripts'] : [];
+        $this->html = isset($serialized['html']) ? (array) $serialized['html'] : [];
+    }
+
+    /**
+     * @param string $framework
+     * @return $this
+     */
+    public function addFramework($framework)
+    {
+        $this->frameworks[$framework] = 1;
+
+        return $this;
+    }
+
+    /**
+     * @param string|array $element
+     * @param int $priority
+     * @param string $location
+     * @return bool
+     *
+     * @example $block->addStyle('assets/js/my.js');
+     * @example $block->addStyle(['href' => 'assets/js/my.js', 'media' => 'screen']);
+     */
+    public function addStyle($element, $priority = 0, $location = 'head')
+    {
+        if (!is_array($element)) {
+            $element = ['href' => (string) $element];
+        }
+        if (empty($element['href'])) {
+            return false;
+        }
+        if (!isset($this->styles[$location])) {
+            $this->styles[$location] = [];
+        }
+
+        $id = !empty($element['id']) ? ['id' => (string) $element['id']] : [];
+        $href = $element['href'];
+        $type = !empty($element['type']) ? (string) $element['type'] : 'text/css';
+        $media = !empty($element['media']) ? (string) $element['media'] : null;
+        unset(
+            $element['tag'],
+            $element['id'],
+            $element['rel'],
+            $element['content'],
+            $element['href'],
+            $element['type'],
+            $element['media']
+        );
+
+        $this->styles[$location][md5($href) . sha1($href)] = [
+                ':type' => 'file',
+                ':priority' => (int) $priority,
+                'href' => $href,
+                'type' => $type,
+                'media' => $media,
+                'element' => $element
+            ] + $id;
+
+        return true;
+    }
+
+    /**
+     * @param string|array $element
+     * @param int $priority
+     * @param string $location
+     * @return bool
+     */
+    public function addInlineStyle($element, $priority = 0, $location = 'head')
+    {
+        if (!is_array($element)) {
+            $element = ['content' => (string) $element];
+        }
+        if (empty($element['content'])) {
+            return false;
+        }
+        if (!isset($this->styles[$location])) {
+            $this->styles[$location] = [];
+        }
+
+        $content = (string) $element['content'];
+        $type = !empty($element['type']) ? (string) $element['type'] : 'text/css';
+
+        $this->styles[$location][md5($content) . sha1($content)] = [
+            ':type' => 'inline',
+            ':priority' => (int) $priority,
+            'content' => $content,
+            'type' => $type
+        ];
+
+        return true;
+    }
+
+    /**
+     * @param string|array $element
+     * @param int $priority
+     * @param string $location
+     * @return bool
+     */
+    public function addScript($element, $priority = 0, $location = 'head')
+    {
+        if (!is_array($element)) {
+            $element = ['src' => (string) $element];
+        }
+        if (empty($element['src'])) {
+            return false;
+        }
+        if (!isset($this->scripts[$location])) {
+            $this->scripts[$location] = [];
+        }
+
+        $src = $element['src'];
+        $type = !empty($element['type']) ? (string) $element['type'] : 'text/javascript';
+        $defer = isset($element['defer']) ? true : false;
+        $async = isset($element['async']) ? true : false;
+        $handle = !empty($element['handle']) ? (string) $element['handle'] : '';
+
+        $this->scripts[$location][md5($src) . sha1($src)] = [
+            ':type' => 'file',
+            ':priority' => (int) $priority,
+            'src' => $src,
+            'type' => $type,
+            'defer' => $defer,
+            'async' => $async,
+            'handle' => $handle
+        ];
+
+        return true;
+    }
+
+    /**
+     * @param string|array $element
+     * @param int $priority
+     * @param string $location
+     * @return bool
+     */
+    public function addInlineScript($element, $priority = 0, $location = 'head')
+    {
+        if (!is_array($element)) {
+            $element = ['content' => (string) $element];
+        }
+        if (empty($element['content'])) {
+            return false;
+        }
+        if (!isset($this->scripts[$location])) {
+            $this->scripts[$location] = [];
+        }
+
+        $content = (string) $element['content'];
+        $type = !empty($element['type']) ? (string) $element['type'] : 'text/javascript';
+
+        $this->scripts[$location][md5($content) . sha1($content)] = [
+            ':type' => 'inline',
+            ':priority' => (int) $priority,
+            'content' => $content,
+            'type' => $type
+        ];
+
+        return true;
+    }
+
+    /**
+     * @param string $html
+     * @param int $priority
+     * @param string $location
+     * @return bool
+     */
+    public function addHtml($html, $priority = 0, $location = 'bottom')
+    {
+        if (empty($html) || !is_string($html)) {
+            return false;
+        }
+        if (!isset($this->html[$location])) {
+            $this->html[$location] = [];
+        }
+
+        $this->html[$location][md5($html) . sha1($html)] = [
+            ':priority' => (int) $priority,
+            'html' => $html
+        ];
+
+        return true;
+    }
+
+    /**
+     * @return array
+     */
+    protected function getAssetsFast()
+    {
+        $assets = [
+            'frameworks' => $this->frameworks,
+            'styles' => $this->styles,
+            'scripts' => $this->scripts,
+            'html' => $this->html
+        ];
+
+        foreach ($this->blocks as $block) {
+            if ($block instanceof HtmlBlock) {
+                $blockAssets = $block->getAssetsFast();
+                $assets['frameworks'] += $blockAssets['frameworks'];
+
+                foreach ($blockAssets['styles'] as $location => $styles) {
+                    if (!isset($assets['styles'][$location])) {
+                        $assets['styles'][$location] = $styles;
+                    } elseif ($styles) {
+                        $assets['styles'][$location] += $styles;
+                    }
+                }
+
+                foreach ($blockAssets['scripts'] as $location => $scripts) {
+                    if (!isset($assets['scripts'][$location])) {
+                        $assets['scripts'][$location] = $scripts;
+                    } elseif ($scripts) {
+                        $assets['scripts'][$location] += $scripts;
+                    }
+                }
+
+                foreach ($blockAssets['html'] as $location => $htmls) {
+                    if (!isset($assets['html'][$location])) {
+                        $assets['html'][$location] = $htmls;
+                    } elseif ($htmls) {
+                        $assets['html'][$location] += $htmls;
+                    }
+                }
+            }
+        }
+
+        return $assets;
+    }
+
+    /**
+     * @param string $type
+     * @param string $location
+     * @return array
+     */
+    protected function getAssetsInLocation($type, $location)
+    {
+        $assets = $this->getAssetsFast();
+
+        if (empty($assets[$type][$location])) {
+            return [];
+        }
+
+        $styles = $assets[$type][$location];
+        $this->sortAssetsInLocation($styles);
+
+        return $styles;
+    }
+
+    /**
+     * @param array $items
+     */
+    protected function sortAssetsInLocation(array &$items)
+    {
+        $count = 0;
+        foreach ($items as &$item) {
+            $item[':order'] = ++$count;
+        }
+        unset($item);
+
+        uasort(
+            $items,
+            function ($a, $b) {
+                return ($a[':priority'] === $b[':priority'])
+                    ? $a[':order'] - $b[':order'] : $a[':priority'] - $b[':priority'];
+            }
+        );
+    }
+
+    /**
+     * @param array $array
+     */
+    protected function sortAssets(array &$array)
+    {
+        foreach ($array as $location => &$items) {
+            $this->sortAssetsInLocation($items);
+        }
+    }
+}

system/src/Grav/Framework/ContentBlock/HtmlBlockInterface.php

@@ -0,0 +1,94 @@
+<?php
+/**
+ * @package    Grav\Framework\ContentBlock
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\ContentBlock;
+
+/**
+ * Interface HtmlBlockInterface
+ * @package Grav\Framework\ContentBlock
+ */
+interface HtmlBlockInterface extends ContentBlockInterface
+{
+    /**
+     * @return array
+     */
+    public function getAssets();
+
+    /**
+     * @return array
+     */
+    public function getFrameworks();
+
+    /**
+     * @param string $location
+     * @return array
+     */
+    public function getStyles($location = 'head');
+
+    /**
+     * @param string $location
+     * @return array
+     */
+    public function getScripts($location = 'head');
+
+    /**
+     * @param string $location
+     * @return array
+     */
+    public function getHtml($location = 'bottom');
+
+    /**
+     * @param string $framework
+     * @return $this
+     */
+    public function addFramework($framework);
+
+    /**
+     * @param string|array $element
+     * @param int $priority
+     * @param string $location
+     * @return bool
+     *
+     * @example $block->addStyle('assets/js/my.js');
+     * @example $block->addStyle(['href' => 'assets/js/my.js', 'media' => 'screen']);
+     */
+    public function addStyle($element, $priority = 0, $location = 'head');
+
+    /**
+     * @param string|array $element
+     * @param int $priority
+     * @param string $location
+     * @return bool
+     */
+    public function addInlineStyle($element, $priority = 0, $location = 'head');
+
+    /**
+     * @param string|array $element
+     * @param int $priority
+     * @param string $location
+     * @return bool
+     */
+    public function addScript($element, $priority = 0, $location = 'head');
+
+
+    /**
+     * @param string|array $element
+     * @param int $priority
+     * @param string $location
+     * @return bool
+     */
+    public function addInlineScript($element, $priority = 0, $location = 'head');
+
+    /**
+     * @param string $html
+     * @param int $priority
+     * @param string $location
+     * @return bool
+     */
+    public function addHtml($html, $priority = 0, $location = 'bottom');
+}

system/src/Grav/Framework/Object/Access/ArrayAccessTrait.php

@@ -0,0 +1,64 @@
+<?php
+/**
+ * @package    Grav\Framework\Object
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Object\Access;
+
+/**
+ * ArrayAccess Object Trait
+ * @package Grav\Framework\Object
+ */
+trait ArrayAccessTrait
+{
+    /**
+     * Whether or not an offset exists.
+     *
+     * @param mixed $offset  An offset to check for.
+     * @return bool          Returns TRUE on success or FALSE on failure.
+     */
+    public function offsetExists($offset)
+    {
+        return $this->hasProperty($offset);
+    }
+
+    /**
+     * Returns the value at specified offset.
+     *
+     * @param mixed $offset  The offset to retrieve.
+     * @return mixed         Can return all value types.
+     */
+    public function offsetGet($offset)
+    {
+        return $this->getProperty($offset);
+    }
+
+    /**
+     * Assigns a value to the specified offset.
+     *
+     * @param mixed $offset  The offset to assign the value to.
+     * @param mixed $value   The value to set.
+     */
+    public function offsetSet($offset, $value)
+    {
+        $this->setProperty($offset, $value);
+    }
+
+    /**
+     * Unsets an offset.
+     *
+     * @param mixed $offset  The offset to unset.
+     */
+    public function offsetUnset($offset)
+    {
+        $this->unsetProperty($offset);
+    }
+
+    abstract public function hasProperty($property);
+    abstract public function getProperty($property, $default = null);
+    abstract public function setProperty($property, $value);
+    abstract public function unsetProperty($property);
+}

system/src/Grav/Framework/Object/Access/NestedArrayAccessTrait.php

@@ -0,0 +1,64 @@
+<?php
+/**
+ * @package    Grav\Framework\Object
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Object\Access;
+
+/**
+ * Nested ArrayAccess Object Trait
+ * @package Grav\Framework\Object
+ */
+trait NestedArrayAccessTrait
+{
+    /**
+     * Whether or not an offset exists.
+     *
+     * @param mixed $offset  An offset to check for.
+     * @return bool          Returns TRUE on success or FALSE on failure.
+     */
+    public function offsetExists($offset)
+    {
+        return $this->hasNestedProperty($offset);
+    }
+
+    /**
+     * Returns the value at specified offset.
+     *
+     * @param mixed $offset  The offset to retrieve.
+     * @return mixed         Can return all value types.
+     */
+    public function offsetGet($offset)
+    {
+        return $this->getNestedProperty($offset);
+    }
+
+    /**
+     * Assigns a value to the specified offset.
+     *
+     * @param mixed $offset  The offset to assign the value to.
+     * @param mixed $value   The value to set.
+     */
+    public function offsetSet($offset, $value)
+    {
+        $this->setNestedProperty($offset, $value);
+    }
+
+    /**
+     * Unsets an offset.
+     *
+     * @param mixed $offset  The offset to unset.
+     */
+    public function offsetUnset($offset)
+    {
+        $this->unsetNestedProperty($offset);
+    }
+
+    abstract public function hasNestedProperty($property, $separator = null);
+    abstract public function getNestedProperty($property, $default = null, $separator = null);
+    abstract public function setNestedProperty($property, $value, $separator = null);
+    abstract public function unsetNestedProperty($property, $separator = null);
+}

system/src/Grav/Framework/Object/Access/NestedPropertyCollectionTrait.php

@@ -0,0 +1,124 @@
+<?php
+/**
+ * @package    Grav\Framework\Object
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Object\Access;
+
+use Grav\Framework\Object\Interfaces\NestedObjectInterface;
+
+/**
+ * Nested Properties Collection Trait
+ * @package Grav\Framework\Object\Properties
+ */
+trait NestedPropertyCollectionTrait
+{
+    /**
+     * @param string $property      Object property to be matched.
+     * @param string $separator     Separator, defaults to '.'
+     * @return array                Key/Value pairs of the properties.
+     */
+    public function hasNestedProperty($property, $separator = null)
+    {
+        $list = [];
+
+        /** @var NestedObjectInterface $element */
+        foreach ($this->getIterator() as $id => $element) {
+            $list[$id] = $element->hasNestedProperty($property, $separator);
+        }
+
+        return $list;
+    }
+
+    /**
+     * @param string $property      Object property to be fetched.
+     * @param mixed $default        Default value if not set.
+     * @param string $separator     Separator, defaults to '.'
+     * @return array                Key/Value pairs of the properties.
+     */
+    public function getNestedProperty($property, $default = null, $separator = null)
+    {
+        $list = [];
+
+        /** @var NestedObjectInterface $element */
+        foreach ($this->getIterator() as $id => $element) {
+            $list[$id] = $element->getNestedProperty($property, $default, $separator);
+        }
+
+        return $list;
+    }
+
+    /**
+     * @param string $property      Object property to be updated.
+     * @param string $value         New value.
+     * @param string $separator     Separator, defaults to '.'
+     * @return $this
+     */
+    public function setNestedProperty($property, $value, $separator = null)
+    {
+        /** @var NestedObjectInterface $element */
+        foreach ($this->getIterator() as $element) {
+            $element->setNestedProperty($property, $value, $separator);
+        }
+
+        return $this;
+    }
+
+    /**
+     * @param string $property      Object property to be updated.
+     * @param string $separator     Separator, defaults to '.'
+     * @return $this
+     */
+    public function unsetNestedProperty($property, $separator = null)
+    {
+        /** @var NestedObjectInterface $element */
+        foreach ($this->getIterator() as $element) {
+            $element->unsetNestedProperty($property, $separator);
+        }
+
+        return $this;
+    }
+
+    /**
+     * @param string $property      Object property to be updated.
+     * @param string $default       Default value.
+     * @param string $separator     Separator, defaults to '.'
+     * @return $this
+     */
+    public function defNestedProperty($property, $default, $separator = null)
+    {
+        /** @var NestedObjectInterface $element */
+        foreach ($this->getIterator() as $element) {
+            $element->defNestedProperty($property, $default, $separator);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Group items in the collection by a field.
+     *
+     * @param string $property      Object property to be used to make groups.
+     * @param string $separator     Separator, defaults to '.'
+     * @return array
+     */
+    public function group($property, $separator = null)
+    {
+        $list = [];
+
+        /** @var NestedObjectInterface $element */
+        foreach ($this->getIterator() as $element) {
+            $list[(string) $element->getNestedProperty($property, null, $separator)][] = $element;
+        }
+
+        return $list;
+    }
+
+    /**
+     * @return \Traversable
+     */
+    abstract public function getIterator();
+}

system/src/Grav/Framework/Object/Access/NestedPropertyTrait.php

@@ -0,0 +1,182 @@
+<?php
+/**
+ * @package    Grav\Framework\Object
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Object\Access;
+
+use Grav\Framework\Object\Interfaces\ObjectInterface;
+
+/**
+ * Nested Property Object Trait
+ * @package Grav\Framework\Object\Traits
+ */
+trait NestedPropertyTrait
+{
+    /**
+     * @param string $property      Object property name.
+     * @param string $separator     Separator, defaults to '.'
+     * @return bool                 True if property has been defined (can be null).
+     */
+    public function hasNestedProperty($property, $separator = null)
+    {
+        $test = new \stdClass;
+
+        return $this->getNestedProperty($property, $test, $separator) !== $test;
+    }
+
+    /**
+     * @param string $property      Object property to be fetched.
+     * @param mixed $default        Default value if property has not been set.
+     * @param string $separator     Separator, defaults to '.'
+     * @return mixed                Property value.
+     */
+    public function getNestedProperty($property, $default = null, $separator = null)
+    {
+        $separator = $separator ?: '.';
+        $path = explode($separator, $property);
+        $offset = array_shift($path);
+
+        if (!$this->hasProperty($offset)) {
+            return $default;
+        }
+
+        $current = $this->getProperty($offset);
+
+        while ($path) {
+            // Get property of nested Object.
+            if ($current instanceof ObjectInterface) {
+                if (method_exists($current, 'getNestedProperty')) {
+                    return $current->getNestedProperty(implode($separator, $path), $default, $separator);
+                }
+                return $current->getProperty(implode($separator, $path), $default);
+            }
+
+            $offset = array_shift($path);
+
+            if ((is_array($current) || is_a($current, 'ArrayAccess')) && isset($current[$offset])) {
+                $current = $current[$offset];
+            } elseif (is_object($current) && isset($current->{$offset})) {
+                $current = $current->{$offset};
+            } else {
+                return $default;
+            }
+        };
+
+        return $current;
+    }
+
+
+    /**
+     * @param string $property      Object property to be updated.
+     * @param string $value         New value.
+     * @param string $separator     Separator, defaults to '.'
+     * @return $this
+     * @throws \RuntimeException
+     */
+    public function setNestedProperty($property, $value, $separator = null)
+    {
+        $separator = $separator ?: '.';
+        $path = explode($separator, $property);
+        $offset = array_shift($path);
+
+        if (!$path) {
+            $this->setProperty($offset, $value);
+
+            return $this;
+        }
+
+        $current = &$this->doGetProperty($offset, null, true);
+
+        while ($path) {
+            $offset = array_shift($path);
+
+            // Handle arrays and scalars.
+            if ($current === null) {
+                $current = [$offset => []];
+            } elseif (is_array($current)) {
+                if (!isset($current[$offset])) {
+                    $current[$offset] = [];
+                }
+            } else {
+                throw new \RuntimeException('Cannot set nested property on non-array value');
+            }
+
+            $current = &$current[$offset];
+        };
+
+        $current = $value;
+
+        return $this;
+    }
+
+    /**
+     * @param string $property      Object property to be updated.
+     * @param string $separator     Separator, defaults to '.'
+     * @return $this
+     * @throws \RuntimeException
+     */
+    public function unsetNestedProperty($property, $separator = null)
+    {
+        $separator = $separator ?: '.';
+        $path = explode($separator, $property);
+        $offset = array_shift($path);
+
+        if (!$path) {
+            $this->unsetProperty($offset);
+
+            return $this;
+        }
+
+        $last = array_pop($path);
+        $current = &$this->doGetProperty($offset, null, true);
+
+        while ($path) {
+            $offset = array_shift($path);
+
+            // Handle arrays and scalars.
+            if ($current === null) {
+                return $this;
+            }
+            if (is_array($current)) {
+                if (!isset($current[$offset])) {
+                    return $this;
+                }
+            } else {
+                throw new \RuntimeException('Cannot set nested property on non-array value');
+            }
+
+            $current = &$current[$offset];
+        };
+
+        unset($current[$last]);
+
+        return $this;
+    }
+
+    /**
+     * @param string $property      Object property to be updated.
+     * @param string $default       Default value.
+     * @param string $separator     Separator, defaults to '.'
+     * @return $this
+     * @throws \RuntimeException
+     */
+    public function defNestedProperty($property, $default, $separator = null)
+    {
+        if (!$this->hasNestedProperty($property, $separator)) {
+            $this->setNestedProperty($property, $default, $separator);
+        }
+
+        return $this;
+    }
+
+
+    abstract public function hasProperty($property);
+    abstract public function getProperty($property, $default = null);
+    abstract public function setProperty($property, $value);
+    abstract public function unsetProperty($property);
+    abstract protected function &doGetProperty($property, $default = null, $doCreate = false);
+}

system/src/Grav/Framework/Object/Access/OverloadedPropertyTrait.php

@@ -0,0 +1,64 @@
+<?php
+/**
+ * @package    Grav\Framework\Object
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Object\Access;
+
+/**
+ * Overloaded Property Object Trait
+ * @package Grav\Framework\Object\Access
+ */
+trait OverloadedPropertyTrait
+{
+    /**
+     * Checks whether or not an offset exists.
+     *
+     * @param mixed $offset  An offset to check for.
+     * @return bool          Returns TRUE on success or FALSE on failure.
+     */
+    public function __isset($offset)
+    {
+        return $this->hasProperty($offset);
+    }
+
+    /**
+     * Returns the value at specified offset.
+     *
+     * @param mixed $offset  The offset to retrieve.
+     * @return mixed         Can return all value types.
+     */
+    public function __get($offset)
+    {
+        return $this->getProperty($offset);
+    }
+
+    /**
+     * Assigns a value to the specified offset.
+     *
+     * @param mixed $offset  The offset to assign the value to.
+     * @param mixed $value   The value to set.
+     */
+    public function __set($offset, $value)
+    {
+        $this->setProperty($offset, $value);
+    }
+
+    /**
+     * Magic method to unset the attribute
+     *
+     * @param mixed $offset The name value to unset
+     */
+    public function __unset($offset)
+    {
+        $this->unsetProperty($offset);
+    }
+
+    abstract public function hasProperty($property);
+    abstract public function getProperty($property, $default = null);
+    abstract public function setProperty($property, $value);
+    abstract public function unsetProperty($property);
+}

system/src/Grav/Framework/Object/ArrayObject.php

@@ -0,0 +1,26 @@
+<?php
+/**
+ * @package    Grav\Framework\Object
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Object;
+
+use Grav\Framework\Object\Access\NestedArrayAccessTrait;
+use Grav\Framework\Object\Access\NestedPropertyTrait;
+use Grav\Framework\Object\Access\OverloadedPropertyTrait;
+use Grav\Framework\Object\Base\ObjectTrait;
+use Grav\Framework\Object\Interfaces\NestedObjectInterface;
+use Grav\Framework\Object\Property\ArrayPropertyTrait;
+
+/**
+ * Array Object class.
+ *
+ * @package Grav\Framework\Object
+ */
+class ArrayObject implements NestedObjectInterface, \ArrayAccess
+{
+    use ObjectTrait, ArrayPropertyTrait, NestedPropertyTrait, OverloadedPropertyTrait, NestedArrayAccessTrait;
+}

system/src/Grav/Framework/Object/Base/ObjectCollectionTrait.php

@@ -0,0 +1,190 @@
+<?php
+/**
+ * @package    Grav\Framework\Object
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Object\Base;
+
+use Grav\Framework\Object\Interfaces\ObjectInterface;
+
+/**
+ * ObjectCollection Trait
+ * @package Grav\Framework\Object
+ */
+trait ObjectCollectionTrait
+{
+    use ObjectTrait {
+        setKey as public;
+    }
+
+    /**
+     * Create a copy from this collection by cloning all objects in the collection.
+     *
+     * @return static
+     */
+    public function copy()
+    {
+        $list = [];
+        foreach ($this->getIterator() as $key => $value) {
+            $list[$key] = is_object($value) ? clone $value : $value;
+        }
+
+        // TODO: remove when PHP 5.6 is minimum (with doctrine/collections v1.4).
+        if (!method_exists($this, 'createFrom')) {
+            return new static($list);
+        }
+
+        return $this->createFrom($list);
+    }
+
+    /**
+     * @return array
+     */
+    public function getObjectKeys()
+    {
+        return $this->call('getKey');
+    }
+
+    /**
+     * @param string $property      Object property to be matched.
+     * @return array                Key/Value pairs of the properties.
+     */
+    public function doHasProperty($property)
+    {
+        $list = [];
+
+        /** @var ObjectInterface $element */
+        foreach ($this->getIterator() as $id => $element) {
+            $list[$id] = $element->hasProperty($property);
+        }
+
+        return $list;
+    }
+
+    /**
+     * @param string $property      Object property to be fetched.
+     * @param mixed $default        Default value if not set.
+     * @return array                Key/Value pairs of the properties.
+     */
+    public function doGetProperty($property, $default = null)
+    {
+        $list = [];
+
+        /** @var ObjectInterface $element */
+        foreach ($this->getIterator() as $id => $element) {
+            $list[$id] = $element->getProperty($property, $default);
+        }
+
+        return $list;
+    }
+
+    /**
+     * @param string $property  Object property to be updated.
+     * @param string $value     New value.
+     * @return $this
+     */
+    public function doSetProperty($property, $value)
+    {
+        /** @var ObjectInterface $element */
+        foreach ($this->getIterator() as $element) {
+            $element->setProperty($property, $value);
+        }
+
+        return $this;
+    }
+
+    /**
+     * @param string $property  Object property to be updated.
+     * @return $this
+     */
+    public function doUnsetProperty($property)
+    {
+        /** @var ObjectInterface $element */
+        foreach ($this->getIterator() as $element) {
+            $element->unsetProperty($property);
+        }
+
+        return $this;
+    }
+
+    /**
+     * @param string $property  Object property to be updated.
+     * @param string $default   Default value.
+     * @return $this
+     */
+    public function doDefProperty($property, $default)
+    {
+        /** @var ObjectInterface $element */
+        foreach ($this->getIterator() as $element) {
+            $element->defProperty($property, $default);
+        }
+
+        return $this;
+    }
+
+    /**
+     * @param string $method        Method name.
+     * @param array  $arguments     List of arguments passed to the function.
+     * @return array                Return values.
+     */
+    public function call($method, array $arguments = [])
+    {
+        $list = [];
+
+        foreach ($this->getIterator() as $id => $element) {
+            $list[$id] = method_exists($element, $method)
+                ? call_user_func_array([$element, $method], $arguments) : null;
+        }
+
+        return $list;
+    }
+
+    /**
+     * Group items in the collection by a field and return them as associated array.
+     *
+     * @param string $property
+     * @return array
+     */
+    public function group($property)
+    {
+        $list = [];
+
+        /** @var ObjectInterface $element */
+        foreach ($this->getIterator() as $element) {
+            $list[(string) $element->getProperty($property)][] = $element;
+        }
+
+        return $list;
+    }
+
+    /**
+     * Group items in the collection by a field and return them as associated array of collections.
+     *
+     * @param string $property
+     * @return static[]
+     */
+    public function collectionGroup($property)
+    {
+        $collections = [];
+        foreach ($this->group($property) as $id => $elements) {
+            // TODO: remove when PHP 5.6 is minimum (with doctrine/collections v1.4).
+            if (!method_exists($this, 'createFrom')) {
+                $collection = new static($elements);
+            } else {
+                $collection = $this->createFrom($elements);
+            }
+
+            $collections[$id] = $collection;
+        }
+
+        return $collections;
+    }
+
+    /**
+     * @return \Traversable
+     */
+    abstract public function getIterator();
+}

system/src/Grav/Framework/Object/Base/ObjectTrait.php

@@ -0,0 +1,174 @@
+<?php
+/**
+ * @package    Grav\Framework\Object
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Object\Base;
+
+/**
+ * Object trait.
+ *
+ * @package Grav\Framework\Object
+ */
+trait ObjectTrait
+{
+    static protected $prefix;
+    static protected $type;
+
+    /**
+     * @var string
+     */
+    private $_key;
+
+    /**
+     * @param bool $prefix
+     * @return string
+     */
+    public function getType($prefix = true)
+    {
+        if (static::$type) {
+            return ($prefix ? static::$prefix : '') . static::$type;
+        }
+
+        $class = get_class($this);
+        return ($prefix ? static::$prefix : '') . strtolower(substr($class, strrpos($class, '\\') + 1));
+    }
+
+    /**
+     * @return string
+     */
+    public function getKey()
+    {
+        return $this->_key ?: $this->getType() . '@' . spl_object_hash($this);
+    }
+
+    /**
+     * @param string $property      Object property name.
+     * @return bool                 True if property has been defined (can be null).
+     */
+    public function hasProperty($property)
+    {
+        return $this->doHasProperty($property);
+    }
+
+    /**
+     * @param string $property      Object property to be fetched.
+     * @param mixed $default        Default value if property has not been set.
+     * @return mixed                Property value.
+     */
+    public function getProperty($property, $default = null)
+    {
+        return $this->doGetProperty($property, $default);
+    }
+
+    /**
+     * @param string $property      Object property to be updated.
+     * @param string $value         New value.
+     * @return $this
+     */
+    public function setProperty($property, $value)
+    {
+        $this->doSetProperty($property, $value);
+
+        return $this;
+    }
+
+    /**
+     * @param string  $property     Object property to be unset.
+     * @return $this
+     */
+    public function unsetProperty($property)
+    {
+        $this->doUnsetProperty($property);
+
+        return $this;
+    }
+
+    /**
+     * @param string  $property     Object property to be defined.
+     * @param mixed   $default      Default value.
+     * @return $this
+     */
+    public function defProperty($property, $default)
+    {
+        if (!$this->hasProperty($property)) {
+            $this->setProperty($property, $default);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Implements Serializable interface.
+     *
+     * @return string
+     */
+    public function serialize()
+    {
+        return serialize($this->jsonSerialize());
+    }
+
+    /**
+     * @param string $serialized
+     */
+    public function unserialize($serialized)
+    {
+        $data = unserialize($serialized);
+
+        if (method_exists($this, 'initObjectProperties')) {
+            $this->initObjectProperties();
+        }
+        $this->doUnserialize($data);
+    }
+
+    /**
+     * @param array $serialized
+     */
+    protected function doUnserialize(array $serialized)
+    {
+        if (!isset($serialized['key'], $serialized['type'], $serialized['elements']) || $serialized['type'] !== $this->getType()) {
+            throw new \InvalidArgumentException("Cannot unserialize '{$this->getType()}': Bad data");
+        }
+
+        $this->setKey($serialized['key']);
+        $this->setElements($serialized['elements']);
+    }
+
+    /**
+     * Implements JsonSerializable interface.
+     *
+     * @return array
+     */
+    public function jsonSerialize()
+    {
+        return ['key' => $this->getKey(), 'type' => $this->getType(), 'elements' => $this->getElements()];
+    }
+
+    /**
+     * Returns a string representation of this object.
+     *
+     * @return string
+     */
+    public function __toString()
+    {
+        return $this->getKey();
+    }
+
+    /**
+     * @param string $key
+     */
+    protected function setKey($key)
+    {
+        $this->_key = (string) $key;
+    }
+
+    abstract protected function doHasProperty($property);
+    abstract protected function &doGetProperty($property, $default = null, $doCreate = false);
+    abstract protected function doSetProperty($property, $value);
+    abstract protected function doUnsetProperty($property);
+    abstract protected function getElements();
+    abstract protected function setElements(array $elements);
+}

system/src/Grav/Framework/Object/Interfaces/NestedObjectInterface.php

@@ -0,0 +1,57 @@
+<?php
+/**
+ * @package    Grav\Framework\Object
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Object\Interfaces;
+
+/**
+ * Object Interface
+ * @package Grav\Framework\Object
+ */
+interface NestedObjectInterface extends ObjectInterface
+{
+    /**
+     * @param string $property      Object property name.
+     * @param string $separator     Separator, defaults to '.'
+     * @return bool                 True if property has been defined (can be null).
+     */
+    public function hasNestedProperty($property, $separator = null);
+
+    /**
+     * @param string $property      Object property to be fetched.
+     * @param mixed $default        Default value if property has not been set.
+     * @param string $separator     Separator, defaults to '.'
+     * @return mixed                Property value.
+     */
+    public function getNestedProperty($property, $default = null, $separator = null);
+
+    /**
+     * @param string $property      Object property to be updated.
+     * @param string $value         New value.
+     * @param string $separator     Separator, defaults to '.'
+     * @return $this
+     * @throws \RuntimeException
+     */
+    public function setNestedProperty($property, $value, $separator = null);
+
+    /**
+     * @param string $property      Object property to be defined.
+     * @param string $default       Default value.
+     * @param string $separator     Separator, defaults to '.'
+     * @return $this
+     * @throws \RuntimeException
+     */
+    public function defNestedProperty($property, $default, $separator = null);
+
+    /**
+     * @param string $property      Object property to be unset.
+     * @param string $separator     Separator, defaults to '.'
+     * @return $this
+     * @throws \RuntimeException
+     */
+    public function unsetNestedProperty($property, $separator = null);
+}

system/src/Grav/Framework/Object/Interfaces/ObjectCollectionInterface.php

@@ -0,0 +1,66 @@
+<?php
+/**
+ * @package    Grav\Framework\Object
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Object\Interfaces;
+
+use Grav\Framework\Collection\CollectionInterface;
+
+/**
+ * ObjectCollection Interface
+ * @package Grav\Framework\Collection
+ */
+interface ObjectCollectionInterface extends CollectionInterface, ObjectInterface
+{
+    /**
+     * Create a copy from this collection by cloning all objects in the collection.
+     *
+     * @return static
+     */
+    public function copy();
+
+    /**
+     * @param string $key
+     * @return $this
+     */
+    public function setKey($key);
+
+    /**
+     * @return array
+     */
+    public function getObjectKeys();
+
+    /**
+     * @param string $property      Object property to be fetched.
+     * @param mixed $default        Default value if not set.
+     * @return array                Property value.
+     */
+    public function getProperty($property, $default = null);
+
+    /**
+     * @param string $name          Method name.
+     * @param array  $arguments     List of arguments passed to the function.
+     * @return array                Return values.
+     */
+    public function call($name, array $arguments);
+
+    /**
+     * Group items in the collection by a field and return them as associated array.
+     *
+     * @param string $property
+     * @return array
+     */
+    public function group($property);
+
+    /**
+     * Group items in the collection by a field and return them as associated array of collections.
+     *
+     * @param string $property
+     * @return static[]
+     */
+    public function collectionGroup($property);
+}

system/src/Grav/Framework/Object/Interfaces/ObjectInterface.php

@@ -0,0 +1,59 @@
+<?php
+/**
+ * @package    Grav\Framework\Object
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Object\Interfaces;
+
+/**
+ * Object Interface
+ * @package Grav\Framework\Object
+ */
+interface ObjectInterface extends \Serializable, \JsonSerializable
+{
+    /**
+     * @return string
+     */
+    public function getType();
+
+    /**
+     * @return string
+     */
+    public function getKey();
+
+    /**
+     * @param string $property      Object property name.
+     * @return bool                 True if property has been defined (can be null).
+     */
+    public function hasProperty($property);
+
+    /**
+     * @param string $property      Object property to be fetched.
+     * @param mixed $default        Default value if property has not been set.
+     * @return mixed                Property value.
+     */
+    public function getProperty($property, $default = null);
+
+    /**
+     * @param string $property      Object property to be updated.
+     * @param string $value         New value.
+     * @return $this
+     */
+    public function setProperty($property, $value);
+
+    /**
+     * @param string  $property     Object property to be defined.
+     * @param mixed   $default      Default value.
+     * @return $this
+     */
+    public function defProperty($property, $default);
+
+    /**
+     * @param string  $property     Object property to be unset.
+     * @return $this
+     */
+    public function unsetProperty($property);
+}

system/src/Grav/Framework/Object/LazyObject.php

@@ -0,0 +1,26 @@
+<?php
+/**
+ * @package    Grav\Framework\Object
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Object;
+
+use Grav\Framework\Object\Access\NestedArrayAccessTrait;
+use Grav\Framework\Object\Access\NestedPropertyTrait;
+use Grav\Framework\Object\Access\OverloadedPropertyTrait;
+use Grav\Framework\Object\Base\ObjectTrait;
+use Grav\Framework\Object\Interfaces\NestedObjectInterface;
+use Grav\Framework\Object\Property\LazyPropertyTrait;
+
+/**
+ * Lazy Object class.
+ *
+ * @package Grav\Framework\Object
+ */
+class LazyObject implements NestedObjectInterface, \ArrayAccess
+{
+    use ObjectTrait, LazyPropertyTrait, NestedPropertyTrait, OverloadedPropertyTrait, NestedArrayAccessTrait;
+}

system/src/Grav/Framework/Object/ObjectCollection.php

@@ -0,0 +1,48 @@
+<?php
+/**
+ * @package    Grav\Framework\Object
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Object;
+
+use Grav\Framework\Collection\ArrayCollection;
+use Grav\Framework\Object\Access\NestedPropertyCollectionTrait;
+use Grav\Framework\Object\Base\ObjectCollectionTrait;
+use Grav\Framework\Object\Interfaces\NestedObjectInterface;
+use Grav\Framework\Object\Interfaces\ObjectCollectionInterface;
+
+/**
+ * Object Collection
+ * @package Grav\Framework\Object
+ */
+class ObjectCollection extends ArrayCollection implements ObjectCollectionInterface, NestedObjectInterface
+{
+    use ObjectCollectionTrait, NestedPropertyCollectionTrait {
+        NestedPropertyCollectionTrait::group insteadof ObjectCollectionTrait;
+    }
+
+    /**
+     * @param array $elements
+     * @param string $key
+     * @throws \InvalidArgumentException
+     */
+    public function __construct(array $elements = [], $key = null)
+    {
+        parent::__construct($this->setElements($elements));
+
+        $this->setKey($key);
+    }
+
+    protected function getElements()
+    {
+        return $this->toArray();
+    }
+
+    protected function setElements(array $elements)
+    {
+        return $elements;
+    }
+}

system/src/Grav/Framework/Object/Property/ArrayPropertyTrait.php

@@ -0,0 +1,109 @@
+<?php
+/**
+ * @package    Grav\Framework\Object
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Object\Property;
+
+/**
+ * Array Property Trait
+ *
+ * Stores all object properties into an array.
+ *
+ * @package Grav\Framework\Object\Property
+ */
+trait ArrayPropertyTrait
+{
+    /**
+     * Properties of the object.
+     * @var array
+     */
+    private $_elements;
+
+    /**
+     * @param array $elements
+     * @param string $key
+     * @throws \InvalidArgumentException
+     */
+    public function __construct(array $elements = [], $key = null)
+    {
+        $this->setElements($elements);
+        $this->setKey($key);
+    }
+
+    /**
+     * @param string $property      Object property name.
+     * @return bool                 True if property has been defined (can be null).
+     */
+    protected function doHasProperty($property)
+    {
+        return array_key_exists($property, $this->_elements);
+    }
+
+    /**
+     * @param string $property      Object property to be fetched.
+     * @param mixed $default        Default value if property has not been set.
+     * @param bool $doCreate        Set true to create variable.
+     * @return mixed                Property value.
+     */
+    protected function &doGetProperty($property, $default = null, $doCreate = false)
+    {
+        if (!array_key_exists($property, $this->_elements)) {
+            if ($doCreate) {
+                $this->_elements[$property] = null;
+            } else {
+                return $default;
+            }
+        }
+
+        return $this->_elements[$property];
+    }
+
+    /**
+     * @param string $property      Object property to be updated.
+     * @param mixed  $value         New value.
+     */
+    protected function doSetProperty($property, $value)
+    {
+        $this->_elements[$property] = $value;
+    }
+
+    /**
+     * @param string  $property     Object property to be unset.
+     */
+    protected function doUnsetProperty($property)
+    {
+        unset($this->_elements[$property]);
+    }
+
+    /**
+     * @param string $property
+     * @param mixed|null $default
+     * @return mixed|null
+     */
+    protected function getElement($property, $default = null)
+    {
+        return array_key_exists($property, $this->_elements) ? $this->_elements[$property] : $default;
+    }
+
+    /**
+     * @return array
+     */
+    protected function getElements()
+    {
+        return $this->_elements;
+    }
+
+    /**
+     * @param array $elements
+     */
+    protected function setElements(array $elements)
+    {
+        $this->_elements = $elements;
+    }
+
+    abstract protected function setKey($key);
+}

system/src/Grav/Framework/Object/Property/LazyPropertyTrait.php

@@ -0,0 +1,117 @@
+<?php
+/**
+ * @package    Grav\Framework\Object
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Object\Property;
+
+/**
+ * Lazy Mixed Property Trait
+ *
+ * Stores defined object properties as class member variables and the rest into an array. Object properties are lazy
+ * loaded from the array.
+ *
+ * You may define following methods for the member variables:
+ * - `$this->offsetLoad($offset, $value)` called first time object property gets accessed
+ * - `$this->offsetPrepare($offset, $value)` called on every object property set
+ * - `$this->offsetSerialize($offset, $value)` called when the raw or serialized object property value is needed
+ *
+ * @package Grav\Framework\Object\Property
+ */
+trait LazyPropertyTrait
+{
+    use ArrayPropertyTrait, ObjectPropertyTrait {
+        ObjectPropertyTrait::__construct insteadof ArrayPropertyTrait;
+        ArrayPropertyTrait::doHasProperty as hasArrayProperty;
+        ArrayPropertyTrait::doGetProperty as getArrayProperty;
+        ArrayPropertyTrait::doSetProperty as setArrayProperty;
+        ArrayPropertyTrait::doUnsetProperty as unsetArrayProperty;
+        ArrayPropertyTrait::getElement as getArrayElement;
+        ArrayPropertyTrait::getElements as getArrayElements;
+        ArrayPropertyTrait::setElements insteadof ObjectPropertyTrait;
+        ObjectPropertyTrait::doHasProperty as hasObjectProperty;
+        ObjectPropertyTrait::doGetProperty as getObjectProperty;
+        ObjectPropertyTrait::doSetProperty as setObjectProperty;
+        ObjectPropertyTrait::doUnsetProperty as unsetObjectProperty;
+        ObjectPropertyTrait::getElement as getObjectElement;
+        ObjectPropertyTrait::getElements as getObjectElements;
+    }
+
+    /**
+     * @param string $property      Object property name.
+     * @return bool                 True if property has been defined (can be null).
+     */
+    protected function doHasProperty($property)
+    {
+        return $this->hasArrayProperty($property) || $this->hasObjectProperty($property);
+    }
+
+    /**
+     * @param string $property      Object property to be fetched.
+     * @param mixed $default        Default value if property has not been set.
+     * @return mixed                Property value.
+     */
+    protected function &doGetProperty($property, $default = null, $doCreate = false)
+    {
+        if ($this->hasObjectProperty($property)) {
+            return $this->getObjectProperty($property, $default, function ($default = null) use ($property) {
+                return $this->getArrayProperty($property, $default);
+            });
+        }
+
+        return $this->getArrayProperty($property, $default, $doCreate);
+    }
+
+    /**
+     * @param string $property      Object property to be updated.
+     * @param mixed  $value         New value.
+     * @return $this
+     */
+    protected function doSetProperty($property, $value)
+    {
+        if ($this->hasObjectProperty($property)) {
+            $this->setObjectProperty($property, $value);
+        } else {
+            $this->setArrayProperty($property, $value);
+        }
+
+        return $this;
+    }
+
+    /**
+     * @param string  $property     Object property to be unset.
+     * @return $this
+     */
+    protected function doUnsetProperty($property)
+    {
+        $this->hasObjectProperty($property) ?
+            $this->unsetObjectProperty($property) : $this->unsetArrayProperty($property);
+
+        return $this;
+    }
+
+    /**
+     * @param string $property
+     * @param mixed|null $default
+     * @return mixed|null
+     */
+    protected function getElement($property, $default = null)
+    {
+        if ($this->isPropertyLoaded($property)) {
+            return $this->getObjectElement($property, $default);
+        }
+
+        return $this->getArrayElement($property, $default);
+    }
+
+    /**
+     * @return array
+     */
+    protected function getElements()
+    {
+        return $this->getObjectElements() + $this->getArrayElements();
+    }
+}

system/src/Grav/Framework/Object/Property/MixedPropertyTrait.php

@@ -0,0 +1,122 @@
+<?php
+/**
+ * @package    Grav\Framework\Object
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Object\Property;
+
+/**
+ * Mixed Property Trait
+ *
+ * Stores defined object properties as class member variables and the rest into an array.
+ *
+ * You may define following methods for member variables:
+ * - `$this->offsetLoad($offset, $value)` called first time object property gets accessed
+ * - `$this->offsetPrepare($offset, $value)` called on every object property set
+ * - `$this->offsetSerialize($offset, $value)` called when the raw or serialized object property value is needed
+
+ *
+ * @package Grav\Framework\Object\Property
+ */
+trait MixedPropertyTrait
+{
+    use ArrayPropertyTrait, ObjectPropertyTrait {
+        ObjectPropertyTrait::__construct insteadof ArrayPropertyTrait;
+        ArrayPropertyTrait::doHasProperty as hasArrayProperty;
+        ArrayPropertyTrait::doGetProperty as getArrayProperty;
+        ArrayPropertyTrait::doSetProperty as setArrayProperty;
+        ArrayPropertyTrait::doUnsetProperty as unsetArrayProperty;
+        ArrayPropertyTrait::getElement as getArrayElement;
+        ArrayPropertyTrait::getElements as getArrayElements;
+        ArrayPropertyTrait::setElements as setArrayElements;
+        ObjectPropertyTrait::doHasProperty as hasObjectProperty;
+        ObjectPropertyTrait::doGetProperty as getObjectProperty;
+        ObjectPropertyTrait::doSetProperty as setObjectProperty;
+        ObjectPropertyTrait::doUnsetProperty as unsetObjectProperty;
+        ObjectPropertyTrait::getElement as getObjectElement;
+        ObjectPropertyTrait::getElements as getObjectElements;
+        ObjectPropertyTrait::setElements as setObjectElements;
+    }
+
+    /**
+     * @param string $property      Object property name.
+     * @return bool                 True if property has been defined (can be null).
+     */
+    protected function doHasProperty($property)
+    {
+        return $this->hasArrayProperty($property) || $this->hasObjectProperty($property);
+    }
+
+    /**
+     * @param string $property      Object property to be fetched.
+     * @param mixed $default        Default value if property has not been set.
+     * @return mixed                Property value.
+     */
+    protected function &doGetProperty($property, $default = null, $doCreate = false)
+    {
+        if ($this->hasObjectProperty($property)) {
+            return $this->getObjectProperty($property);
+        }
+
+        return $this->getArrayProperty($property, $default, $doCreate);
+    }
+
+    /**
+     * @param string $property      Object property to be updated.
+     * @param mixed  $value         New value.
+     * @return $this
+     */
+    protected function doSetProperty($property, $value)
+    {
+        $this->hasObjectProperty($property)
+            ? $this->setObjectProperty($property, $value) : $this->setArrayProperty($property, $value);
+
+        return $this;
+    }
+
+    /**
+     * @param string  $property     Object property to be unset.
+     * @return $this
+     */
+    protected function doUnsetProperty($property)
+    {
+        $this->hasObjectProperty($property) ?
+            $this->unsetObjectProperty($property) : $this->unsetArrayProperty($property);
+
+        return $this;
+    }
+
+    /**
+     * @param string $property
+     * @param mixed|null $default
+     * @return mixed|null
+     */
+    protected function getElement($property, $default = null)
+    {
+        if ($this->hasObjectProperty($property)) {
+            return $this->getObjectElement($property, $default);
+        }
+
+        return $this->getArrayElement($property, $default);
+    }
+
+    /**
+     * @return array
+     */
+    protected function getElements()
+    {
+        return $this->getObjectElements() + $this->getArrayElements();
+    }
+
+    /**
+     * @param array $elements
+     */
+    protected function setElements(array $elements)
+    {
+        $this->setObjectElements(array_intersect_key($elements, $this->_definedProperties));
+        $this->setArrayElements(array_diff_key($elements, $this->_definedProperties));
+    }
+}

system/src/Grav/Framework/Object/Property/ObjectPropertyTrait.php

@@ -0,0 +1,203 @@
+<?php
+/**
+ * @package    Grav\Framework\Object
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Object\Property;
+
+/**
+ * Object Property Trait
+ *
+ * Stores all properties as class member variables or object properties. All properties need to be defined as protected
+ * properties. Undefined properties will throw an error.
+ *
+ * Additionally you may define following methods:
+ * - `$this->offsetLoad($offset, $value)` called first time object property gets accessed
+ * - `$this->offsetPrepare($offset, $value)` called on every object property set
+ * - `$this->offsetSerialize($offset, $value)` called when the raw or serialized object property value is needed
+ *
+ * @package Grav\Framework\Object\Property
+ */
+trait ObjectPropertyTrait
+{
+    /**
+     * @var array
+     */
+    private $_definedProperties;
+
+    /**
+     * @param array $elements
+     * @param string $key
+     * @throws \InvalidArgumentException
+     */
+    public function __construct(array $elements = [], $key = null)
+    {
+        $this->initObjectProperties();
+        $this->setElements($elements);
+        $this->setKey($key);
+    }
+
+    /**
+     * @param string $property      Object property name.
+     * @return bool                 True if property has been loaded.
+     */
+    protected function isPropertyLoaded($property)
+    {
+        return !empty($this->_definedProperties[$property]);
+    }
+
+    /**
+     * @param string $offset
+     * @param mixed $value
+     * @return mixed
+     */
+    protected function offsetLoad($offset, $value)
+    {
+        $methodName = "offsetLoad_{$offset}";
+
+        return method_exists($this, $methodName)? $this->{$methodName}($value) : $value;
+    }
+
+    /**
+     * @param string $offset
+     * @param mixed $value
+     * @return mixed
+     */
+    protected function offsetPrepare($offset, $value)
+    {
+        $methodName = "offsetPrepare_{$offset}";
+
+        return method_exists($this, $methodName) ? $this->{$methodName}($value) : $value;
+    }
+
+    /**
+     * @param string $offset
+     * @param mixed $value
+     * @return mixed
+     */
+    protected function offsetSerialize($offset, $value)
+    {
+        $methodName = "offsetSerialize_{$offset}";
+
+        return method_exists($this, $methodName) ? $this->{$methodName}($value) : $value;
+    }
+
+    /**
+     * @param string $property      Object property name.
+     * @return bool                 True if property has been defined (can be null).
+     */
+    protected function doHasProperty($property)
+    {
+        return array_key_exists($property, $this->_definedProperties);
+    }
+
+    /**
+     * @param string $property      Object property to be fetched.
+     * @param mixed $default        Default value if property has not been set.
+     * @param bool $doCreate        Set true to create variable.
+     * @return mixed                Property value.
+     */
+    protected function &doGetProperty($property, $default = null, $doCreate = false)
+    {
+        if (!array_key_exists($property, $this->_definedProperties)) {
+            throw new \InvalidArgumentException("Property '{$property}' does not exist in the object!");
+        }
+
+        if (empty($this->_definedProperties[$property])) {
+            if ($doCreate === true) {
+                $this->_definedProperties[$property] = true;
+                $this->{$property} = null;
+            } elseif (is_callable($doCreate)) {
+                $this->_definedProperties[$property] = true;
+                $this->{$property} = $this->offsetLoad($property, $doCreate());
+            } else {
+                return $default;
+            }
+        }
+
+        return $this->{$property};
+    }
+
+    /**
+     * @param string $property      Object property to be updated.
+     * @param mixed  $value         New value.
+     * @throws \InvalidArgumentException
+     */
+    protected function doSetProperty($property, $value)
+    {
+        if (!array_key_exists($property, $this->_definedProperties)) {
+            throw new \InvalidArgumentException("Property '{$property}' does not exist in the object!");
+        }
+
+        $this->_definedProperties[$property] = true;
+        $this->{$property} = $this->offsetPrepare($property, $value);
+    }
+
+    /**
+     * @param string  $property     Object property to be unset.
+     */
+    protected function doUnsetProperty($property)
+    {
+        if (!array_key_exists($property, $this->_definedProperties)) {
+            return;
+        }
+
+        $this->_definedProperties[$property] = false;
+        unset($this->{$property});
+    }
+
+    protected function initObjectProperties()
+    {
+        $this->_definedProperties = [];
+        foreach (get_object_vars($this) as $property => $value) {
+            if ($property[0] !== '_') {
+                $this->_definedProperties[$property] = ($value !== null);
+            }
+        }
+    }
+
+    /**
+     * @param string $property
+     * @param mixed|null $default
+     * @return mixed|null
+     */
+    protected function getElement($property, $default = null)
+    {
+        if (empty($this->_definedProperties[$property])) {
+            return $default;
+        }
+
+        return $this->offsetSerialize($property, $this->{$property});
+    }
+
+    /**
+     * @return array
+     */
+    protected function getElements()
+    {
+        $properties = array_intersect_key(get_object_vars($this), array_filter($this->_definedProperties));
+
+        $elements = [];
+        foreach ($properties as $offset => $value) {
+            $elements[$offset] = $this->offsetSerialize($offset, $value);
+        }
+
+        return $elements;
+    }
+
+    /**
+     * @param array $elements
+     */
+    protected function setElements(array $elements)
+    {
+        foreach ($elements as $property => $value) {
+            $this->setProperty($property, $value);
+        }
+    }
+
+    abstract public function setProperty($property, $value);
+    abstract protected function setKey($key);
+}

system/src/Grav/Framework/Object/PropertyObject.php

@@ -0,0 +1,26 @@
+<?php
+/**
+ * @package    Grav\Framework\Object
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Object;
+
+use Grav\Framework\Object\Access\NestedArrayAccessTrait;
+use Grav\Framework\Object\Access\NestedPropertyTrait;
+use Grav\Framework\Object\Access\OverloadedPropertyTrait;
+use Grav\Framework\Object\Base\ObjectTrait;
+use Grav\Framework\Object\Interfaces\NestedObjectInterface;
+use Grav\Framework\Object\Property\ObjectPropertyTrait;
+
+/**
+ * Property Object class.
+ *
+ * @package Grav\Framework\Object
+ */
+class PropertyObject implements NestedObjectInterface, \ArrayAccess
+{
+    use ObjectTrait, ObjectPropertyTrait, NestedPropertyTrait, OverloadedPropertyTrait, NestedArrayAccessTrait;
+}

system/src/Grav/Framework/Psr7/AbstractUri.php

@@ -0,0 +1,406 @@
+<?php
+/**
+ * @package    Grav\Framework\Psr7
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Psr7;
+
+use Grav\Framework\Uri\UriPartsFilter;
+use Psr\Http\Message\UriInterface;
+
+/**
+ * Bare minimum PSR7 implementation.
+ *
+ * @package Grav\Framework\Uri\Psr7
+ */
+abstract class AbstractUri implements UriInterface
+{
+    protected static $defaultPorts = [
+        'http'  => 80,
+        'https' => 443
+    ];
+
+    /** @var string Uri scheme. */
+    private $scheme = '';
+
+    /** @var string Uri user. */
+    private $user = '';
+
+    /** @var string Uri password. */
+    private $password = '';
+
+    /** @var string Uri host. */
+    private $host = '';
+
+    /** @var int|null Uri port. */
+    private $port;
+
+    /** @var string Uri path. */
+    private $path = '';
+
+    /** @var string Uri query string (without ?). */
+    private $query = '';
+
+    /** @var string Uri fragment (without #). */
+    private $fragment = '';
+
+    /**
+     * Please define constructor which calls $this->init().
+     */
+    abstract public function __construct();
+
+    /**
+     * @inheritdoc
+     */
+    public function getScheme()
+    {
+        return $this->scheme;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getAuthority()
+    {
+        $authority = $this->host;
+
+        $userInfo = $this->getUserInfo();
+        if ($userInfo !== '') {
+            $authority = $userInfo . '@' . $authority;
+        }
+
+        if ($this->port !== null) {
+            $authority .= ':' . $this->port;
+        }
+
+        return $authority;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getUserInfo()
+    {
+        $userInfo = $this->user;
+
+        if ($this->password !== '') {
+            $userInfo .= ':' . $this->password;
+        }
+
+        return $userInfo;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getHost()
+    {
+        return $this->host;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getPort()
+    {
+        return $this->port;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getPath()
+    {
+        return $this->path;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getQuery()
+    {
+        return $this->query;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function getFragment()
+    {
+        return $this->fragment;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function withScheme($scheme)
+    {
+        $scheme = UriPartsFilter::filterScheme($scheme);
+
+        if ($this->scheme === $scheme) {
+            return $this;
+        }
+
+        $new = clone $this;
+        $new->scheme = $scheme;
+        $new->unsetDefaultPort();
+        $new->validate();
+
+        return $new;
+    }
+
+    /**
+     * @inheritdoc
+     * @throws \InvalidArgumentException
+     */
+    public function withUserInfo($user, $password = '')
+    {
+        $user = UriPartsFilter::filterUserInfo($user);
+        $password = UriPartsFilter::filterUserInfo($password);
+
+        if ($this->user === $user && $this->password === $password) {
+            return $this;
+        }
+
+        $new = clone $this;
+        $new->user = $user;
+        $new->password = $user !== '' ? $password : '';
+        $new->validate();
+
+        return $new;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function withHost($host)
+    {
+        $host = UriPartsFilter::filterHost($host);
+
+        if ($this->host === $host) {
+            return $this;
+        }
+
+        $new = clone $this;
+        $new->host = $host;
+        $new->validate();
+
+        return $new;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function withPort($port)
+    {
+        $port = UriPartsFilter::filterPort($port);
+
+        if ($this->port === $port) {
+            return $this;
+        }
+
+        $new = clone $this;
+        $new->port = $port;
+        $new->unsetDefaultPort();
+        $new->validate();
+
+        return $new;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function withPath($path)
+    {
+        $path = UriPartsFilter::filterPath($path);
+
+        if ($this->path === $path) {
+            return $this;
+        }
+
+        $new = clone $this;
+        $new->path = $path;
+        $new->validate();
+
+        return $new;
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function withQuery($query)
+    {
+        $query = UriPartsFilter::filterQueryOrFragment($query);
+
+        if ($this->query === $query) {
+            return $this;
+        }
+
+        $new = clone $this;
+        $new->query = $query;
+
+        return $new;
+    }
+
+    /**
+     * @inheritdoc
+     * @throws \InvalidArgumentException
+     */
+    public function withFragment($fragment)
+    {
+        $fragment = UriPartsFilter::filterQueryOrFragment($fragment);
+
+        if ($this->fragment === $fragment) {
+            return $this;
+        }
+
+        $new = clone $this;
+        $new->fragment = $fragment;
+
+        return $new;
+    }
+
+    /**
+     * @return string
+     */
+    public function __toString()
+    {
+        return $this->getUrl();
+    }
+
+    /**
+     * @return array
+     */
+    protected function getParts()
+    {
+        return [
+            'scheme'    => $this->scheme,
+            'host'      => $this->host,
+            'port'      => $this->port,
+            'user'      => $this->user,
+            'pass'      => $this->password,
+            'path'      => $this->path,
+            'query'     => $this->query,
+            'fragment'  => $this->fragment
+        ];
+    }
+
+    /**
+     * Return the fully qualified base URL ( like http://getgrav.org ).
+     *
+     * Note that this method never includes a trailing /
+     *
+     * @return string
+     */
+    protected function getBaseUrl()
+    {
+        $uri = '';
+
+        $scheme = $this->getScheme();
+        if ($scheme !== '') {
+            $uri .= $scheme . ':';
+        }
+
+        $authority = $this->getAuthority();
+        if ($authority !== '' || $scheme === 'file') {
+            $uri .= '//' . $authority;
+        }
+
+        return $uri;
+    }
+
+    /**
+     * @return string
+     */
+    protected function getUrl()
+    {
+        $uri = $this->getBaseUrl() . $this->getPath();
+
+        $query = $this->getQuery();
+        if ($query !== '') {
+            $uri .= '?' . $query;
+        }
+
+        $fragment = $this->getFragment();
+        if ($fragment !== '') {
+            $uri .= '#' . $fragment;
+        }
+
+        return $uri;
+    }
+
+    /**
+     * @return string
+     */
+    protected function getUser()
+    {
+        return $this->user;
+    }
+
+    /**
+     * @return string
+     */
+    protected function getPassword()
+    {
+        return $this->password;
+    }
+
+    /**
+     * @param array $parts
+     * @throws \InvalidArgumentException
+     */
+    protected function initParts(array $parts)
+    {
+        $this->scheme = isset($parts['scheme']) ? UriPartsFilter::filterScheme($parts['scheme']) : '';
+        $this->user = isset($parts['user']) ? UriPartsFilter::filterUserInfo($parts['user']) : '';
+        $this->password = isset($parts['pass']) ? UriPartsFilter::filterUserInfo($parts['pass']) : '';
+        $this->host = isset($parts['host']) ? UriPartsFilter::filterHost($parts['host']) : '';
+        $this->port = isset($parts['port']) ? UriPartsFilter::filterPort((int)$parts['port']) : null;
+        $this->path = isset($parts['path']) ? UriPartsFilter::filterPath($parts['path']) : '';
+        $this->query = isset($parts['query']) ? UriPartsFilter::filterQueryOrFragment($parts['query']) : '';
+        $this->fragment = isset($parts['fragment']) ? UriPartsFilter::filterQueryOrFragment($parts['fragment']) : '';
+
+        $this->unsetDefaultPort();
+        $this->validate();
+    }
+
+    /**
+     * @throws \InvalidArgumentException
+     */
+    private function validate()
+    {
+        if ($this->host === '' && ($this->scheme === 'http' || $this->scheme === 'https')) {
+            throw new \InvalidArgumentException('Uri with a scheme must have a host');
+        }
+
+        if ($this->getAuthority() === '') {
+            if (0 === strpos($this->path, '//')) {
+                throw new \InvalidArgumentException('The path of a URI without an authority must not start with two slashes \'//\'');
+            }
+            if ($this->scheme === '' && false !== strpos(explode('/', $this->path, 2)[0], ':')) {
+                throw new \InvalidArgumentException('A relative URI must not have a path beginning with a segment containing a colon');
+            }
+        } elseif (isset($this->path[0]) && $this->path[0] !== '/') {
+            throw new \InvalidArgumentException('The path of a URI with an authority must start with a slash \'/\' or be empty');
+        }
+    }
+
+    protected function isDefaultPort()
+    {
+        $scheme = $this->scheme;
+        $port = $this->port;
+
+        return $this->port === null
+            || (isset(static::$defaultPorts[$scheme]) && $port === static::$defaultPorts[$scheme]);
+    }
+
+    private function unsetDefaultPort()
+    {
+        if ($this->isDefaultPort()) {
+            $this->port = null;
+        }
+    }
+}

system/src/Grav/Framework/Route/Route.php

@@ -0,0 +1,301 @@
+<?php
+/**
+ * @package    Grav\Framework\Route
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Route;
+
+use Grav\Framework\Uri\UriFactory;
+
+/**
+ * Implements Grav Route.
+ *
+ * @package Grav\Framework\Route
+ */
+class Route
+{
+    /** @var string */
+    private $root = '';
+
+    /** @var string */
+    private $language = '';
+
+    /** @var string */
+    private $route = '';
+
+    /** @var array */
+    private $gravParams = [];
+
+    /** @var array */
+    private $queryParams = [];
+
+    /**
+     * You can use `RouteFactory` functions to create new `Route` objects.
+     *
+     * @param array $parts
+     * @throws \InvalidArgumentException
+     */
+    public function __construct(array $parts = [])
+    {
+        $this->initParts($parts);
+    }
+
+    /**
+     * @return array
+     */
+    public function getParts()
+    {
+        return [
+            'path' => $this->getUriPath(),
+            'query' => $this->getUriQuery(),
+            'grav' => [
+                'root' => $this->root,
+                'language' => $this->language,
+                'route' => $this->route,
+                'grav_params' => $this->gravParams,
+                'query_params' => $this->queryParams,
+            ],
+        ];
+    }
+
+    /**
+     * @return string
+     */
+    public function getRootPrefix()
+    {
+        return $this->root;
+    }
+
+    /**
+     * @return string
+     */
+    public function getLanguagePrefix()
+    {
+        return $this->language !== '' ? '/' . $this->language : '';
+    }
+
+    /**
+     * @param int $offset
+     * @param int|null $length
+     * @return string
+     */
+    public function getRoute($offset = 0, $length = null)
+    {
+        if ($offset !== 0 || $length !== null) {
+            return ($offset === 0 ? '/' : '') . implode('/', $this->getRouteParts($offset, $length));
+        }
+
+        return '/' . $this->route;
+    }
+
+    /**
+     * @param int $offset
+     * @param int|null $length
+     * @return array
+     */
+    public function getRouteParts($offset = 0, $length = null)
+    {
+        $parts = explode('/', $this->route);
+
+        if ($offset !== 0 || $length !== null) {
+            $parts = array_slice($parts, $offset, $length);
+        }
+
+        return $parts;
+    }
+
+    /**
+     * Return array of both query and Grav parameters.
+     *
+     * If a parameter exists in both, prefer Grav parameter.
+     *
+     * @return array
+     */
+    public function getParams()
+    {
+        return $this->gravParams + $this->queryParams;
+    }
+
+    /**
+     * @return array
+     */
+    public function getGravParams()
+    {
+        return $this->gravParams;
+    }
+
+    /**
+     * @return array
+     */
+    public function getQueryParams()
+    {
+        return $this->queryParams;
+    }
+
+    /**
+     * Return value of the parameter, looking into both Grav parameters and query parameters.
+     *
+     * If the parameter exists in both, return Grav parameter.
+     *
+     * @param string $param
+     * @return string|null
+     */
+    public function getParam($param)
+    {
+        $value = $this->getGravParam($param);
+        if ($value === null) {
+            $value = $this->getQueryParam($param);
+        }
+
+        return $value;
+    }
+
+    /**
+     * @param string $param
+     * @return string|null
+     */
+    public function getGravParam($param)
+    {
+        return isset($this->gravParams[$param]) ? $this->gravParams[$param] : null;
+    }
+
+    /**
+     * @param string $param
+     * @return string|null
+     */
+    public function getQueryParam($param)
+    {
+        return isset($this->queryParams[$param]) ? $this->queryParams[$param] : null;
+    }
+
+    /**
+     * @param string $param
+     * @param mixed $value
+     * @return Route
+     */
+    public function withGravParam($param, $value)
+    {
+        return $this->withParam('gravParams', $param, $value);
+    }
+
+    /**
+     * @param string $param
+     * @param mixed $value
+     * @return Route
+     */
+    public function withQueryParam($param, $value)
+    {
+        return $this->withParam('queryParams', $param, $value);
+    }
+
+    /**
+     * @return \Grav\Framework\Uri\Uri
+     */
+    public function getUri()
+    {
+        return UriFactory::createFromParts($this->getParts());
+    }
+
+    /**
+     * @return string
+     */
+    public function __toString()
+    {
+        $url = $this->getUriPath();
+
+        if ($this->queryParams) {
+            $url .= '?' . $this->getUriQuery();
+        }
+
+        return $url;
+    }
+
+    /**
+     * @param string $type
+     * @param string $param
+     * @param mixed $value
+     * @return static
+     */
+    protected function withParam($type, $param, $value)
+    {
+        $oldValue = isset($this->{$type}[$param]) ? $this->{$type}[$param] : null;
+        $newValue = null !== $value ? (string)$value : null;
+
+        if ($oldValue === $newValue) {
+            return $this;
+        }
+
+        $new = clone $this;
+        if ($newValue === null) {
+            unset($new->{$type}[$param]);
+        } else {
+            $new->{$type}[$param] = $newValue;
+        }
+
+        return $new;
+    }
+
+    /**
+     * @return string
+     */
+    protected function getUriPath()
+    {
+        $parts = [$this->root];
+
+        if ($this->language !== '') {
+            $parts[] = $this->language;
+        }
+
+        if ($this->route !== '') {
+            $parts[] = $this->route;
+        }
+
+        if ($this->gravParams) {
+            $parts[] = RouteFactory::buildParams($this->gravParams);
+        }
+
+        return implode('/', $parts);
+    }
+
+    /**
+     * @return string
+     */
+    protected function getUriQuery()
+    {
+        return UriFactory::buildQuery($this->queryParams);
+    }
+
+    /**
+     * @param array $parts
+     */
+    protected function initParts(array $parts)
+    {
+        if (isset($parts['grav'])) {
+            $gravParts = $parts['grav'];
+            $this->root = $gravParts['root'];
+            $this->language = $gravParts['language'];
+            $this->route = $gravParts['route'];
+            $this->gravParams = $gravParts['params'];
+            $this->queryParams = $parts['query_params'];
+
+        } else {
+            $this->root = RouteFactory::getRoot();
+            $this->language = RouteFactory::getLanguage();
+
+            $path = isset($parts['path']) ? $parts['path'] : '/';
+            if (isset($parts['params'])) {
+                $this->route = trim(rawurldecode($path), '/');
+                $this->gravParams = $parts['params'];
+            } else {
+                $this->route = trim(RouteFactory::stripParams($path, true), '/');
+                $this->gravParams = RouteFactory::getParams($path);
+            }
+            if (isset($parts['query'])) {
+                $this->queryParams = UriFactory::parseQuery($parts['query']);
+            }
+        }
+    }
+}

system/src/Grav/Framework/Route/RouteFactory.php

@@ -0,0 +1,131 @@
+<?php
+/**
+ * @package    Grav\Framework\Route
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Route;
+
+/**
+ * Class RouteFactory
+ * @package Grav\Framework\Route
+ */
+class RouteFactory
+{
+    /** @var string */
+    private static $root = '';
+
+    /** @var string */
+    private static $language = '';
+
+    /** @var string */
+    private static $delimiter = ':';
+
+    public static function createFromParts($parts)
+    {
+        return new Route($parts);
+    }
+
+    public static function getRoot()
+    {
+        return self::$root;
+    }
+
+    public static function setRoot($root)
+    {
+        self::$root = rtrim($root, '/');
+    }
+
+    public static function getLanguage()
+    {
+        return self::$language;
+    }
+
+    public static function setLanguage($language)
+    {
+        self::$language = trim($language, '/');
+    }
+
+    public static function getParamValueDelimiter()
+    {
+        return self::$delimiter;
+    }
+
+    public static function setParamValueDelimiter($delimiter)
+    {
+        self::$delimiter = $delimiter;
+    }
+
+    /**
+     * @param array $params
+     * @return string
+     */
+    public static function buildParams(array $params)
+    {
+        if (!$params) {
+            return '';
+        }
+
+        $delimiter = self::$delimiter;
+
+        $output = [];
+        foreach ($params as $key => $value) {
+            $output[] = "{$key}{$delimiter}{$value}";
+        }
+
+        return implode('/', $output);
+    }
+
+    /**
+     * @param string $path
+     * @param bool $decode
+     * @return string
+     */
+    public static function stripParams($path, $decode = false)
+    {
+        $pos = strpos($path, self::$delimiter);
+
+        if ($pos === false) {
+            return $path;
+        }
+
+        $path = dirname(substr($path, 0, $pos));
+        if ($path === '.') {
+            return '';
+        }
+
+        return $decode ? rawurldecode($path) : $path;
+    }
+
+    /**
+     * @param string $path
+     * @return array
+     */
+    public static function getParams($path)
+    {
+        $params = ltrim(substr($path, strlen(static::stripParams($path))), '/');
+
+        return $params !== '' ? static::parseParams($params) : [];
+    }
+
+    /**
+     * @param string $str
+     * @return array
+     */
+    public static function parseParams($str)
+    {
+        $delimiter = self::$delimiter;
+
+        $params = explode('/', $str);
+        foreach ($params as &$param) {
+            $parts = explode($delimiter, $param, 2);
+            if (isset($parts[1])) {
+                $param[rawurldecode($parts[0])] = rawurldecode($parts[1]);
+            }
+        }
+
+        return $params;
+    }
+}

system/src/Grav/Framework/Uri/Uri.php

@@ -0,0 +1,213 @@
+<?php
+/**
+ * @package    Grav\Framework\Uri
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Uri;
+
+use Grav\Framework\Psr7\AbstractUri;
+use GuzzleHttp\Psr7\Uri as GuzzleUri;
+use Psr\Http\Message\UriInterface;
+
+/**
+ * Implements PSR-7 UriInterface.
+ *
+ * @package Grav\Framework\Uri
+ */
+class Uri extends AbstractUri
+{
+    /** @var array Array of Uri query. */
+    private $queryParams;
+
+    /**
+     * You can use `UriFactory` functions to create new `Uri` objects.
+     *
+     * @param array $parts
+     * @throws \InvalidArgumentException
+     */
+    public function __construct(array $parts = [])
+    {
+        $this->initParts($parts);
+    }
+
+    /**
+     * @return string
+     */
+    public function getUser()
+    {
+        return parent::getUser();
+    }
+
+    /**
+     * @return string
+     */
+    public function getPassword()
+    {
+        return parent::getPassword();
+    }
+
+    /**
+     * @return array
+     */
+    public function getParts()
+    {
+        return parent::getParts();
+    }
+
+    /**
+     * @return string
+     */
+    public function getUrl()
+    {
+        return parent::getUrl();
+    }
+
+    /**
+     * @return string
+     */
+    public function getBaseUrl()
+    {
+        return parent::getBaseUrl();
+    }
+
+    /**
+     * @param string $key
+     * @return string|null
+     */
+    public function getQueryParam($key)
+    {
+        $queryParams = $this->getQueryParams();
+
+        return isset($queryParams[$key]) ? $queryParams[$key] : null;
+    }
+
+    /**
+     * @param string $key
+     * @return UriInterface
+     */
+    public function withoutQueryParam($key)
+    {
+        return GuzzleUri::withoutQueryValue($this, $key);
+    }
+
+    /**
+     * @param string $key
+     * @param string|null $value
+     * @return UriInterface
+     */
+    public function withQueryParam($key, $value)
+    {
+        return GuzzleUri::withQueryValue($this, $key, $value);
+    }
+
+    /**
+     * @return array
+     */
+    public function getQueryParams()
+    {
+        if ($this->queryParams === null) {
+            $this->queryParams = UriFactory::parseQuery($this->getQuery());
+        }
+
+        return $this->queryParams;
+    }
+
+    /**
+     * @param array $params
+     * @return UriInterface
+     */
+    public function withQueryParams(array $params)
+    {
+        $query = UriFactory::buildQuery($params);
+
+        return $this->withQuery($query);
+    }
+
+    /**
+     * Whether the URI has the default port of the current scheme.
+     *
+     * `$uri->getPort()` may return the standard port. This method can be used for some non-http/https Uri.
+     *
+     * @return bool
+     */
+    public function isDefaultPort()
+    {
+        return $this->getPort() === null || GuzzleUri::isDefaultPort($this);
+    }
+
+    /**
+     * Whether the URI is absolute, i.e. it has a scheme.
+     *
+     * An instance of UriInterface can either be an absolute URI or a relative reference. This method returns true
+     * if it is the former. An absolute URI has a scheme. A relative reference is used to express a URI relative
+     * to another URI, the base URI. Relative references can be divided into several forms:
+     * - network-path references, e.g. '//example.com/path'
+     * - absolute-path references, e.g. '/path'
+     * - relative-path references, e.g. 'subpath'
+     *
+     * @return bool
+     * @link https://tools.ietf.org/html/rfc3986#section-4
+     */
+    public function isAbsolute()
+    {
+        return GuzzleUri::isAbsolute($this);
+    }
+
+    /**
+     * Whether the URI is a network-path reference.
+     *
+     * A relative reference that begins with two slash characters is termed an network-path reference.
+     *
+     * @return bool
+     * @link https://tools.ietf.org/html/rfc3986#section-4.2
+     */
+    public function isNetworkPathReference()
+    {
+        return GuzzleUri::isNetworkPathReference($this);
+    }
+
+    /**
+     * Whether the URI is a absolute-path reference.
+     *
+     * A relative reference that begins with a single slash character is termed an absolute-path reference.
+     *
+     * @return bool
+     * @link https://tools.ietf.org/html/rfc3986#section-4.2
+     */
+    public function isAbsolutePathReference()
+    {
+        return GuzzleUri::isAbsolutePathReference($this);
+    }
+
+    /**
+     * Whether the URI is a relative-path reference.
+     *
+     * A relative reference that does not begin with a slash character is termed a relative-path reference.
+     *
+     * @return bool
+     * @link https://tools.ietf.org/html/rfc3986#section-4.2
+     */
+    public function isRelativePathReference()
+    {
+        return GuzzleUri::isRelativePathReference($this);
+    }
+
+    /**
+     * Whether the URI is a same-document reference.
+     *
+     * A same-document reference refers to a URI that is, aside from its fragment
+     * component, identical to the base URI. When no base URI is given, only an empty
+     * URI reference (apart from its fragment) is considered a same-document reference.
+     *
+     * @param UriInterface|null $base An optional base URI to compare against
+     * @return bool
+     * @link https://tools.ietf.org/html/rfc3986#section-4.4
+     */
+    public function isSameDocumentReference(UriInterface $base = null)
+    {
+        return GuzzleUri::isSameDocumentReference($this, $base);
+    }
+}

system/src/Grav/Framework/Uri/UriFactory.php

@@ -0,0 +1,159 @@
+<?php
+/**
+ * @package    Grav\Framework\Uri
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Uri;
+
+/**
+ * Class Uri
+ * @package Grav\Framework\Uri
+ */
+class UriFactory
+{
+    /**
+     * @param array $env
+     * @return Uri
+     * @throws \InvalidArgumentException
+     */
+    public static function createFromEnvironment(array $env)
+    {
+        return new Uri(static::parseUrlFromEnvironment($env));
+    }
+
+    /**
+     * @param string $uri
+     * @return Uri
+     * @throws \InvalidArgumentException
+     */
+    public static function createFromString($uri)
+    {
+        return new Uri(static::parseUrl($uri));
+    }
+
+    /**
+     * Creates a URI from a array of `parse_url()` components.
+     *
+     * @param array $parts
+     * @return Uri
+     * @throws \InvalidArgumentException
+     */
+    public static function createFromParts(array $parts)
+    {
+        return new Uri($parts);
+    }
+
+    /**
+     * @param array $env
+     * @return array
+     * @throws \InvalidArgumentException
+     */
+    public static function parseUrlFromEnvironment(array $env)
+    {
+        // Build scheme.
+        if (isset($env['REQUEST_SCHEME'])) {
+            $scheme = strtolower($env['REQUEST_SCHEME']);
+        } else {
+            $https = isset($env['HTTPS']) ? $env['HTTPS'] : '';
+            $scheme = (empty($https) || strtolower($https) === 'off') ? 'http' : 'https';
+        }
+
+        // Build user and password.
+        $user = isset($env['PHP_AUTH_USER']) ? $env['PHP_AUTH_USER'] : '';
+        $pass = isset($env['PHP_AUTH_PW']) ? $env['PHP_AUTH_PW'] : '';
+
+        // Build host.
+        $host = 'localhost';
+        if (isset($env['HTTP_HOST'])) {
+            $host = $env['HTTP_HOST'];
+        } elseif (isset($env['SERVER_NAME'])) {
+            $host = $env['SERVER_NAME'];
+        }
+        // Remove port from HTTP_HOST generated $hostname
+        $host = explode(':', $host)[0];
+
+        // Build port.
+        $port = isset($env['SERVER_PORT']) ? (int)$env['SERVER_PORT'] : null;
+
+        // Build path.
+        $request_uri = isset($env['REQUEST_URI']) ? $env['REQUEST_URI'] : '';
+        $path = parse_url('http://example.com' . $request_uri, PHP_URL_PATH);
+
+        // Build query string.
+        $query = isset($env['QUERY_STRING']) ? $env['QUERY_STRING'] : '';
+        if ($query === '') {
+            $query = parse_url('http://example.com' . $request_uri, PHP_URL_QUERY);
+        }
+
+        // Support ngnix routes.
+        if (strpos($query, '_url=') === 0) {
+            parse_str($query, $q);
+            unset($q['_url']);
+            $query = http_build_query($q);
+        }
+
+        return [
+            'scheme' => $scheme,
+            'user' => $user,
+            'pass' => $pass,
+            'host' => $host,
+            'port' => $port,
+            'path' => $path,
+            'query' => $query
+        ];
+    }
+
+    /**
+     * UTF-8 aware parse_url() implementation.
+     *
+     * @param string $url
+     * @return array
+     * @throws \InvalidArgumentException
+     */
+    public static function parseUrl($url)
+    {
+        if (!is_string($url)) {
+            throw new \InvalidArgumentException('URL must be a string');
+        }
+
+        $encodedUrl = preg_replace_callback(
+            '%[^:/@?&=#]+%u',
+            function ($matches) { return rawurlencode($matches[0]); },
+            $url
+        );
+
+        $parts = parse_url($encodedUrl);
+        if ($parts === false) {
+            throw new \InvalidArgumentException('Malformed URL: ' . $encodedUrl);
+        }
+
+        return $parts;
+    }
+
+    /**
+     * Parse query string and return it as an array.
+     *
+     * @param string $query
+     * @return mixed
+     */
+    public static function parseQuery($query)
+    {
+        parse_str($query, $params);
+
+        return $params;
+    }
+
+    /**
+     * Build query string from variables.
+     *
+     * @param array $params
+     * @return string
+     */
+    public static function buildQuery(array $params)
+    {
+        return $params ? http_build_query($params,  null, ini_get('arg_separator.output'), PHP_QUERY_RFC3986) : '';
+    }
+}

system/src/Grav/Framework/Uri/UriPartsFilter.php

@@ -0,0 +1,140 @@
+<?php
+/**
+ * @package    Grav\Framework\Uri
+ *
+ * @copyright  Copyright (C) 2015 - 2018 Trilby Media, LLC. All rights reserved.
+ * @license    MIT License; see LICENSE file for details.
+ */
+
+namespace Grav\Framework\Uri;
+
+/**
+ * Class Uri
+ * @package Grav\Framework\Uri
+ */
+class UriPartsFilter
+{
+    const HOSTNAME_REGEX = '/^(([a-zA-Z0-9]|[a-zA-Z0-9][a-zA-Z0-9\-]*[a-zA-Z0-9])\.)*([A-Za-z0-9]|[A-Za-z0-9][A-Za-z0-9\-]*[A-Za-z0-9])$/u';
+
+    /**
+     * @param string $scheme
+     * @return string
+     * @throws \InvalidArgumentException If the scheme is invalid.
+     */
+    public static function filterScheme($scheme)
+    {
+        if (!is_string($scheme)) {
+            throw new \InvalidArgumentException('Uri scheme must be a string');
+        }
+
+        return strtolower($scheme);
+    }
+
+    /**
+     * Filters the user info string.
+     *
+     * @param string $info The raw user or password.
+     * @return string The percent-encoded user or password string.
+     * @throws \InvalidArgumentException
+     */
+    public static function filterUserInfo($info)
+    {
+        if (!is_string($info)) {
+            throw new \InvalidArgumentException('Uri user info must be a string');
+        }
+
+        return preg_replace_callback(
+            '/(?:[^a-zA-Z0-9_\-\.~!\$&\'\(\)\*\+,;=]+|%(?![A-Fa-f0-9]{2}))/u',
+            function ($match) {
+                return rawurlencode($match[0]);
+            },
+            $info
+        );
+    }
+
+    /**
+     * @param string $host
+     * @return string
+     * @throws \InvalidArgumentException If the host is invalid.
+     */
+    public static function filterHost($host)
+    {
+        if (!is_string($host)) {
+            throw new \InvalidArgumentException('Uri host must be a string');
+        }
+
+        if (filter_var($host, FILTER_VALIDATE_IP, FILTER_FLAG_IPV6)) {
+            $host = '[' . $host . ']';
+        } elseif ($host && preg_match(static::HOSTNAME_REGEX, $host) !== 1) {
+            throw new \InvalidArgumentException('Uri host name validation failed');
+        }
+
+        return strtolower($host);
+    }
+
+    /**
+     * Filter Uri port.
+     *
+     * This method
+     *
+     * @param int|null $port
+     * @return int|null
+     * @throws \InvalidArgumentException If the port is invalid.
+     */
+    public static function filterPort($port = null)
+    {
+        if (null === $port || (is_int($port) && ($port >= 1 && $port <= 65535))) {
+            return $port;
+        }
+
+        throw new \InvalidArgumentException('Uri port must be null or an integer between 1 and 65535');
+    }
+
+    /**
+     * Filter Uri path.
+     *
+     * This method percent-encodes all reserved characters in the provided path string. This method
+     * will NOT double-encode characters that are already percent-encoded.
+     *
+     * @param  string $path The raw uri path.
+     * @return string       The RFC 3986 percent-encoded uri path.
+     * @throws \InvalidArgumentException If the path is invalid.
+     * @link   http://www.faqs.org/rfcs/rfc3986.html
+     */
+    public static function filterPath($path)
+    {
+        if (!is_string($path)) {
+            throw new \InvalidArgumentException('Uri path must be a string');
+        }
+
+        return preg_replace_callback(
+            '/(?:[^a-zA-Z0-9_\-\.~:@&=\+\$,\/;%]+|%(?![A-Fa-f0-9]{2}))/u',
+            function ($match) {
+                return rawurlencode($match[0]);
+            },
+            $path
+        );
+    }
+
+    /**
+     * Filters the query string or fragment of a URI.
+     *
+     * @param string $query The raw uri query string.
+     * @return string The percent-encoded query string.
+     * @throws \InvalidArgumentException If the query is invalid.
+     */
+    public static function filterQueryOrFragment($query)
+    {
+        if (!is_string($query)) {
+            throw new \InvalidArgumentException('Uri query string and fragment must be a string');
+        }
+
+        return preg_replace_callback(
+            '/(?:[^a-zA-Z0-9_\-\.~!\$&\'\(\)\*\+,;=%:@\/\?]+|%(?![A-Fa-f0-9]{2}))/u',
+            function ($match) {
+                return rawurlencode($match[0]);
+            },
+            $query
+        );
+    }
+}