<?php
/**
 * @file panels_node.module
 *
 * This module provides the "panel" node type.
 * Panel nodes are useful to add additional content to the content area
 * on a per-node base.
 */

// ---------------------------------------------------------------------------
// General Drupal hooks.
/**
 * Implementation of hook_permission().
 */
function panels_node_permission() {
  return array(
    'administer panel-nodes' => array(
      'title' => t('Administer panel nodes'),
      'description' => t('Full administrative access to panel nodes including create, update and delete all'),
    ),
  );
}

/**
 * Implementation of hook_ctools_plugin_directory().
 */
function panels_node_ctools_plugin_directory($module, $plugin) {
  if ($module == 'panels' && $plugin == 'panels_storage') {
    return 'plugins/' . $plugin;
  }
}

/**
 * Implementation of hook_menu().
 */
function panels_node_menu() {
  // Safety: go away if CTools is not at an appropriate version.
  if (!defined('PANELS_REQUIRED_CTOOLS_API') || !module_invoke('ctools', 'api_version', PANELS_REQUIRED_CTOOLS_API)) {
    return array();
  }

  $items['admin/structure/panels/settings/panel-node'] = array(
    'title' => 'Panel nodes',
    'description' => 'Configure which content is available to add to panel node displays.',
    'access arguments' => array('administer panel-nodes'),
    'page callback' => 'panels_node_settings',
    'type' => MENU_LOCAL_TASK,
  );

  // Avoid some repetition on these:
  $base = array(
    'access callback' => 'panels_node_edit_node',
    'access arguments' => array(1),
    'page arguments' => array(1),
    'type' => MENU_LOCAL_TASK,
  );

  $items['node/%node/panel_layout'] = array(
    'title' => 'Panel layout',
    'page callback' => 'panels_node_edit_layout',
    'weight' => 2,
  ) + $base;

  $items['node/%node/panel_content'] = array(
    'title' => 'Panel content',
    'page callback' => 'panels_node_edit_content',
    'weight' => 3,
  ) + $base;

  $items['node/add/panel/choose-layout'] = array(
    'title' => 'Choose layout',
    'access callback' => 'panels_add_panel_access_callback',
    'page callback' => 'panels_node_add',
    'type' => MENU_CALLBACK,
  );

  return $items;
}

/**
 * Access callback to determine if a user has edit access.
 */
function panels_node_edit_node($node) {
  if (!isset($node->panels_node)) {
    return FALSE;
  }

  return node_access('update', $node);
}

/**
 * Access callback to determine if user has access to add panel nodes.
 */
function panels_add_panel_access_callback() {
  return user_access('create panel content') || user_access('administer panel-nodes');
}

/**
 * Override of node add page to force layout selection prior
 * to actually editing a node.
 */
function panels_node_add() {
  $output = '';

  ctools_include('plugins', 'panels');
  ctools_include('common', 'panels');

  $layouts = panels_common_get_allowed_layouts('panels_node');
  return panels_common_print_layout_links($layouts, 'node/add/panel', array('query' => drupal_get_query_parameters()));
}

// ---------------------------------------------------------------------------
// Node hooks.
/**
 * Implementation of hook_node_info().
 */
function panels_node_node_info() {
  // Safety: go away if CTools is not at an appropriate version.
  if (!defined('PANELS_REQUIRED_CTOOLS_API') || !module_invoke('ctools', 'api_version', PANELS_REQUIRED_CTOOLS_API)) {
    return array();
  }

  return array(
    'panel' => array(
      'name' => t('Panel'),
      // We use panels_node_hook so that panels_node private
      // callbacks do not get confused with panels versions of
      // nodeapi callbacks.
      'base' => 'panels_node_hook',
      'body_label' => t('Teaser'),
      'description' => t("A panel layout broken up into rows and columns."),
    ),
  );
}

/**
 * Implementation of hook_access().
 */
function panels_node_node_access($node, $op, $account) {
  if ($op == 'create' && $node != 'panel') {
    return NODE_ACCESS_IGNORE;
  }

  if (is_object($node) && $node->type != 'panel') {
    return NODE_ACCESS_IGNORE;
  }

  if (user_access('administer panel-nodes', $account)) {
    return NODE_ACCESS_ALLOW;
  }
}

/**
 * Implementation of hook_form().
 */
function panels_node_hook_form(&$node, &$form_state) {
  ctools_include('plugins', 'panels');

  $form['panels_node']['#tree'] = TRUE;
  if (empty($node->nid) && arg(0) == 'node' && arg(1) == 'add') {
    // Grab our selected layout from the $node, If it doesn't exist, try arg(3)
    // and if that doesn't work present them with a list to pick from.
    $panel_layout = isset($node->panel_layout) ? $node->panel_layout : arg(3);
    if (empty($panel_layout)) {
      drupal_goto('node/add/panel/choose-layout', array('query' => drupal_get_query_parameters()));
    }

    $layout = panels_get_layout($panel_layout);
    if (empty($layout)) {
      return MENU_NOT_FOUND;
    }
    $form['panels_node']['layout'] = array(
      '#type' => 'value',
      '#value' => $panel_layout,
    );
  }

  $type = node_type_get_type($node);

  $form['title'] = array(
    '#type' => 'textfield',
    '#title' => check_plain($type->title_label),
    '#required' => TRUE,
    '#default_value' => $node->title,
  );

  $css_id = '';
  if (!empty($node->panels_node['css_id'])) {
    $css_id = $node->panels_node['css_id'];
  }

  $form['panels_node']['css_id'] = array(
    '#type' => 'textfield',
    '#title' => t('CSS ID'),
    '#size' => 30,
    '#description' => t('An ID that can be used by CSS to style the panel.'),
    '#default_value' => $css_id,
  );

  // Support for different rendering pipelines
  // Mostly borrowed from panel_context.inc.
  $pipelines = panels_get_renderer_pipelines();

  $options = array();
  foreach ($pipelines as $name => $pipeline) {
    $options[$name] = check_plain($pipeline->admin_title) . '<div class="description">' . check_plain($pipeline->admin_description) . '</div>';
  }

  $form['panels_node']['pipeline'] = array(
    '#type' => 'radios',
    '#options' => $options,
    '#title' => t('Renderer'),
    '#default_value' => isset($node->panels_node['pipeline']) ? $node->panels_node['pipeline'] : variable_get('panels_renderer_default', 'standard'),
  );

  return $form;
}

/**
 * Implementation of hook_validate().
 */
function panels_node_hook_validate($node, $form, &$form_state) {
  if (!$node->nid && empty($node->panels_node['layout'])) {
    form_error($form['panels_node']['layout'], t('Please select a layout.'));
  }
}

/**
 * Implementation of hook_load().
 *
 * Panels does not use revisions for nodes because that would open us up
 * to have completely separate displays, and we'd have to copy them,
 * and that's going to be a LOT of data.
 */
function panels_node_hook_load($nodes) {
  // We shortcut this because only in some really drastic corruption circumstance will this
  // not work.
  $result = db_query("SELECT * FROM {panels_node} WHERE nid IN (:nids)", array(':nids' => array_keys($nodes)));
  foreach ($result as $record) {
    $nodes[$record->nid]->panels_node = (array) $record;
  }
}

/**
 * Implementation of hook_insert().
 */
function panels_node_hook_insert(&$node) {
  // Create a new display and record that.
  $display = panels_new_display();
  $display->layout = $node->panels_node['layout'];
  $display->storage_type = 'panels_node';
  $display->storage_id = $node->nid;

  // Special handling for nodes being imported from an export.module data dump.
  if (!empty($node->export_display)) {
    // This works by overriding the $display set above.
    eval($node->export_display);
    unset($node->export_display);
  }

  panels_save_display($display);
  $node->panels_node['did'] = $display->did;

  db_insert('panels_node')
    ->fields(array(
      'nid' => $node->nid,
      'did' => $display->did,
      'css_id' => $node->panels_node['css_id'],
      'pipeline' => $node->panels_node['pipeline'],
    ))
    ->execute();
}

/**
 * Implementation of hook_delete().
 */
function panels_node_hook_delete(&$node) {
  db_delete('panels_node')->condition('nid', $node->nid)->execute();
  if (!empty($node->panels_node['did'])) {
    panels_delete_display($node->panels_node['did']);
  }
}

/**
 * Implementation of hook_update().
 */
function panels_node_hook_update($node) {
  db_update('panels_node')
    ->condition('nid', $node->nid)
    ->fields(array(
      'css_id' => $node->panels_node['css_id'],
      'pipeline' => $node->panels_node['pipeline'],
    ))
    ->execute();
}

/**
 * Implementation of hook_view().
 */
function panels_node_hook_view($node, $view_mode) {
  static $rendering = array();

  // Prevent loops if someone foolishly puts the node inside itself:
  if (!empty($rendering[$node->nid])) {
    return $node;
  }

  $rendering[$node->nid] = TRUE;
  ctools_include('plugins', 'panels');
  if ($view_mode == 'teaser') {
    // Because our teasier is never the same as our content, *always* provide
    // the read more flag.
    $node->readmore = TRUE;
  }
  else {
    if (!empty($node->panels_node['did'])) {
      $display = panels_load_display($node->panels_node['did']);
      $display->css_id = $node->panels_node['css_id'];
      // TODO: Find a way to make sure this can't node_view.
      $display->context = panels_node_get_context($node);
      $display->cache_key = 'panels_node:' . $node->nid;
      $renderer = panels_get_renderer($node->panels_node['pipeline'], $display);
      $node->content['body'] = array(
        '#markup' => panels_render_display($display, $renderer),
        '#weight' => 0,
      );
    }
  }

  unset($rendering[$node->nid]);
  return $node;
}

// ---------------------------------------------------------------------------
// Administrative pages.
/**
 * Settings for panel nodes.
 */
function panels_node_settings() {
  ctools_include('common', 'panels');
  return drupal_get_form('panels_common_settings', 'panels_node');
}

// ---------------------------------------------------------------------------
// Meat of the Panels API; almost completely passing through to panels.module.
/**
 * Pass through to the panels layout editor.
 */
function panels_node_edit_layout($node) {
//  ctools_include('plugins', 'panels');
  ctools_include('context');
  $display = panels_load_display($node->panels_node['did']);
  $display->context = panels_node_get_context($node);
  return panels_edit_layout($display, t('Save'), "node/$node->nid/panel_layout", 'panels_node');
}

/**
 * Pass through to the panels content editor.
 */
function panels_node_edit_content($node) {
  ctools_include('context');
  $display = panels_load_display($node->panels_node['did']);
  $display->context = panels_node_get_context($node);
  ctools_include('common', 'panels');
  $content_types = panels_common_get_allowed_types('panels_node', $display->context);

  return panels_edit($display, "node/$node->nid/panel_content", $content_types);
}

/**
 * Build the context to use for a panel node.
 */
function panels_node_get_context(&$node) {
  ctools_include('context');
  $context = ctools_context_create('node', $node);
  $context->identifier = t('This node');
  $context->keyword = 'node';
  return array('panel-node' => $context);
}

/**
 * Implementation of hook_export_node_alter().
 *
 * Integrate with export.module for saving panel_nodes into code.
 */
function panels_node_export_node_alter(&$node, $original_node, $method) {
  if ($method == 'export') {
    $node_export_omitted = variable_get('node_export_omitted', array());
    if (variable_get('node_export_method', '') != 'save-edit' && (array_key_exists('panel', $node_export_omitted) && !$node_export_omitted['panel'])) {
      drupal_set_message(t("NOTE: in order to import panel_nodes you must first set the export.module settings to \"Save as a new node then edit\", otherwise it won't work."));
    }
    $display = panels_load_display($node->panels_node['did']);
    $export = panels_export_display($display);
    $node->export_display = $export;
  }
}

/**
 * Implementation of hook_panels_dashboard_blocks().
 *
 * Adds panel nodes information to the Panels dashboard.
 */
function panels_node_panels_dashboard_blocks(&$vars) {
  $vars['links']['panels_node'] = array(
    'title' => l(t('Panel node'), 'node/add/panel'),
    'description' => t('Panel nodes are node content and appear in your searches, but are more limited than panel pages.'),
    'weight' => -1,
  );
}

/**
 * Implements hook_panels_ipe_access().
 */
function panels_node_panels_ipe_access($display) {
  // We only care about Panels displays from panels_node.
  if (isset($display->context['panel-node'])) {
    // Only allow access to use the IPE if the user has 'update' access to
    // the underlying node.
    $node = $display->context['panel-node']->data;
    return node_access('update', $node);
  }
}

// ---------------------------------------------------------------------------
// Callbacks for panel caching.
/**
 * Get display edit cache for a panel node being edited.
 *
 * The key is the second half of the key in this form:
 * panels_node:NID;
 */
function panels_node_panels_cache_get($nid) {
  ctools_include('object-cache');
  $cache = ctools_object_cache_get('panels_node_display_cache', $nid);
  if (empty($cache)) {
    $cache = new stdClass();
    $node = node_load($nid);
    if (empty($node)) {
      return;
    }

    ctools_include('common', 'panels');
    $cache->display = panels_load_display($node->panels_node['did']);
    $cache->display->css_id = $node->panels_node['css_id'];
    $cache->display->context = panels_node_get_context($node);
    $cache->display->cache_key = 'panels_node:' . $node->nid;
    $cache->content_types = panels_common_get_allowed_types('panels_node', $cache->display->context);
    $cache->allwed_layouts = panels_common_get_allowed_layouts('panels_node');
  }

  return $cache;
}

/**
 * Store a display edit in progress in the panels cache.
 */
function panels_node_panels_cache_set($nid, $cache) {
  ctools_include('object-cache');
  ctools_object_cache_set('panels_node_display_cache', $nid, $cache);
}

/**
 * Clear all changes made to a display using the panels cache.
 */
function panels_node_panels_cache_clear($nid, $cache) {
  ctools_include('object-cache');
  ctools_object_cache_clear('panels_node_display_cache', $nid);
}

/**
 * React to a cache save and save the display and clear cache.
 */
function panels_node_panels_cache_save($nid, $cache) {
  panels_save_display($cache->display);
  ctools_include('object-cache');
  ctools_object_cache_clear('panels_node_display_cache', $nid);
}