<?php

/**
 * Base class for testing a module's custom tags.
 */
abstract class MetatagTagsTestBase extends MetatagTestHelper {

  /**
   * All of the meta tags defined by this module which will be tested.
   */
  public $tags = array();

  /**
   * The tag to look for when testing the output.
   */
  public $test_tag = 'meta';

  /**
   * The attribute to look for to indicate which tag.
   */
  public $test_name_attribute = 'name';

  /**
   * The attribute to look for when testing the output.
   */
  public $test_value_attribute = 'content';

  /**
   * {@inheritdoc}
   */
  function setUp(array $modules = array()) {
    $modules[] = 'metatag_test';
    parent::setUp($modules);

    // Create an admin user that can manage meta tags.
    $account = $this->createAdminUser();
    $this->drupalLogin($account);
  }

  /**
   * Tests that this module's tags are available.
   */
  function testTagsArePresent() {
    // Load the global config.
    $this->drupalGet('admin/config/search/metatags/config/global');
    $this->assertResponse(200);

    // Confirm the various meta tags are available.
    foreach ($this->tags as $tag) {
      // Convert tag names to something more suitable for a function name.
      $tag_name = str_replace(array('.', '-', ':'), '_', $tag);

      // Look for a custom method named "{$tag_name}_test_field_xpath", if found
      // use that method to get the xpath definition for this meta tag,
      // otherwise it defaults to just looking for a text input field.
      $method = "{$tag_name}_test_field_xpath";
      if (method_exists($this, $method)) {
        $xpath = $this->$method();
      }
      else {
        $xpath = "//input[@name='metatags[und][{$tag}][value]' and @type='text']";
      }
      $this->assertFieldByXPath($xpath, NULL, format_string('The "%tag" tag field was found.', array('%tag' => $tag)));
    }
  }

  /**
   * Confirm that each tag can be saved and that the output of each tag is
   * correct.
   */
  function testTagsInputOutput() {
    // Load the global config.
    $this->drupalGet('admin/config/search/metatags/config/global');
    $this->assertResponse(200);

    // Update the Global defaults and test them.
    $all_values = $values = array();
    foreach ($this->tags as $tag_raw) {
      // Convert tag names to something more suitable for a function name.
      $tag_name = str_replace(array('.', '-', ':', ' '), '_', $tag_raw);

      // Look for a custom method named "{$tag_name}_test_key", if found use
      // that method to get the test string for this meta tag, otherwise it
      // defaults to the meta tag's name.
      $method = "{$tag_name}_test_key";
      if (method_exists($this, $method)) {
        $test_key = $this->$method();
      }
      else {
        $test_key = "metatags[und][{$tag_raw}][value]";
      }

      // Look for a custom method named "{$tag_name}_test_value", if found use
      // that method to get the test string for this meta tag, otherwise it
      // defaults to just generating a random string.
      $method = "{$tag_name}_test_value";
      if (method_exists($this, $method)) {
        $test_value = $this->$method();
      }
      else {
        // Generate a random string.
        $test_value = $this->getTestTagValue();
      }

      $values[$test_key] = $test_value;

      // Look for a custom method named "{$tag_name}_test_preprocess_output", if
      // found use that method provide any additional processing on the value
      // e.g. adding a prefix.
      $method = "{$tag_name}_test_preprocess_output";
      if (method_exists($this, $method)) {
        $test_value = $this->$method($test_value);
      }

      $all_values[$tag_name] = $test_value;
    }
    $this->drupalPost(NULL, $values, 'Save');
    $this->assertText(strip_tags(t('The meta tag defaults for @label have been saved.', array('@label' => 'Global'))));

    // Load the test page.
    $this->drupalGet('moosqueakoinkmeow');
    $this->assertResponse(200);
    $this->assertText(t('Test page.'));

    // Look for the values.
    foreach ($this->tags as $tag_raw) {
      // Convert tag names to something more suitable for a function name.
      $tag_name = str_replace(array('.', '-', ':', ' '), '_', $tag_raw);

      // Verify this meta tag was output.
      $this->assertTrue(!empty($all_values[$tag_name]));

      // Look for a custom method named "{$tag_name}_test_output_xpath", if
      // found use that method to get the xpath definition for this meta tag,
      // otherwise it defaults to just looking for a meta tag matching:
      // <$test_tag $test_name_attribute=$tag_name $test_value_attribute=$value />
      $method = "{$tag_name}_test_output_xpath";
      if (method_exists($this, $method)) {
        $xpath_string = $this->$method();
      }
      else {
        // Look for a custom method named "{$tag_name}_test_tag", if
        // found use that method to get the xpath definition for this meta tag,
        // otherwise it defaults to $this->test_tag.
        $method = "{$tag_name}_test_tag";
        if (method_exists($this, $method)) {
          $xpath_tag = $this->$method();
        }
        else {
          $xpath_tag = $this->test_tag;
        }

        // Look for a custom method named "{$tag_name}_test_name_attribute", if
        // found use that method to get the xpath definition for this meta tag,
        // otherwise it defaults to $this->test_name_attribute.
        $method = "{$tag_name}_test_name_attribute";
        if (method_exists($this, $method)) {
          $xpath_name_attribute = $this->$method();
        }
        else {
          $xpath_name_attribute = $this->test_name_attribute;
        }

        // Look for a custom method named "{$tag_name}_test_tag_name", if
        // found use that method to get the xpath definition for this meta tag,
        // otherwise it defaults to $tag_name.
        $method = "{$tag_name}_test_tag_name";
        if (method_exists($this, $method)) {
          $xpath_name_tag = $this->$method();
        }
        else {
          $xpath_name_tag = $this->getTestTagName($tag_name);
        }

        // Compile the xpath.
        $xpath_string = "//{$xpath_tag}[@{$xpath_name_attribute}='{$xpath_name_tag}']";
      }

      // Something should have been found.
      $this->assertTrue(!empty($xpath_string));

      // Look for a custom method named "{$tag_name}_test_value_attribute", if
      // found use that method to get the xpath definition for this meta tag,
      // otherwise it defaults to $this->test_value_attribute.
      $method = "{$tag_name}_test_value_attribute";
      if (method_exists($this, $method)) {
        $xpath_value_attribute = $this->$method();
      }
      else {
        $xpath_value_attribute = $this->test_value_attribute;
      }

      // Extract the meta tag from the HTML.
      $xpath = $this->xpath($xpath_string);
      $this->assertEqual(count($xpath), 1, format_string('One @name tag found.', array('@name' => $tag_name)));

      // Most meta tags have an attribute, but some don't.
      if (!empty($xpath_value_attribute)) {
        $this->assertTrue($xpath_value_attribute);
        $this->assertTrue(isset($xpath[0][$xpath_value_attribute]));
        // Help with debugging.
        if (!isset($xpath[0][$xpath_value_attribute])) {
          $this->verbose($xpath, $tag_name . ': ' . $xpath_string);
        }
        else {
          if ((string)$xpath[0][$xpath_value_attribute] != $all_values[$tag_name]) {
            $this->verbose($xpath, $tag_name . ': ' . $xpath_string);
          }
          $this->assertTrue($xpath[0][$xpath_value_attribute]);
          $this->assertEqual($xpath[0][$xpath_value_attribute], $all_values[$tag_name]);//, "The meta tag was found with the expected value.");
        }
      }
      else {
        $this->verbose($xpath, $tag_name . ': ' . $xpath_string);
        $this->assertTrue((string)$xpath[0]);
        $this->assertEqual((string)$xpath[0], $all_values[$tag_name], "The meta tag was found with the expected value.");
      }
    }
  }

  /**
   * Convert a tag's internal name to the string which is actually used in HTML.
   *
   * The meta tag internal name will be machine names, i.e. only contain a-z,
   * A-Z, 0-9 and the underline character. Meta tag names will actually contain
   * any possible character.
   *
   * @param string $tag_name
   *   The tag name to be converted.
   *
   * @return string
   *   The converted tag name.
   */
  public function getTestTagName($tag_name) {
    return $tag_name;
  }

  /**
   * Generate a random value for testing meta tag fields.
   *
   * As a reasonable default, this will generating two words of 8 characters
   * each with simple machine name -style strings.
   *
   * @return string
   *   A normal string.
   */
  public function getTestTagValue() {
    return $this->randomMachineName() . ' ' . $this->randomMachineName();
  }

  /**
   * Generate a URL for an image.
   *
   * @return string
   *   An absolute URL to a non-existant image.
   */
  public function randomImageUrl() {
    return 'http://www.example.com/images/'  . $this->randomMachineName() . '.png';
  }

}