<?php

/**
 * @file
 * Source plugin for the Translation Management system that handles entities.
 */

/**
 * Implements hook_tmgmt_source_plugin_info().
 */
function tmgmt_entity_tmgmt_source_plugin_info() {
  $info['entity'] = array(
    'label' => t('Entity'),
    'description' => t('Source handler for entities.'),
    'plugin controller class' => 'TMGMTEntitySourcePluginController',
    'item types' => array(),
  );

  $entity_types = array_filter(variable_get('entity_translation_entity_types', array()));

  foreach ($entity_types as $entity_key) {
    $entity_info = entity_get_info($entity_key);
    $info['entity']['item types'][$entity_key] = $entity_info['label'];
  }

  return $info;
}

/**
 * Implements hook_form_ID_alter().
 *
 * Alters comment node type select box to filter out comment types that belongs
 * to non entity translatable node types.
 */
function tmgmt_entity_form_tmgmt_ui_entity_source_comment_overview_form_alter(&$form, &$form_state) {

  if (!isset($form['search_wrapper']['search']['node_type'])) {
    return;
  }

  // Change the select name to "type" as in the query submitted value will be
  // passed into node.type condition.
  $form['search_wrapper']['search']['type'] = $form['search_wrapper']['search']['node_type'];
  unset($form['search_wrapper']['search']['node_type']);

  // Set new default value.
  $form['search_wrapper']['search']['type']['#default_value'] = isset($_GET['type']) ? $_GET['type'] : NULL;

}

/**
 * Helper function to get entity translatable bundles.
 *
 * Note that for comment entity type it will return the same as for node as
 * comment bundles have no use (i.e. in queries).
 *
 * @param string $entity_type
 *   Drupal entity type.
 *
 * @return array
 *   Array of key => values, where key is type and value its label.
 */
function tmgmt_entity_get_translatable_bundles($entity_type) {

  // If given entity type does not have entity translations enabled, no reason
  // to continue.
  if (!in_array($entity_type, variable_get('entity_translation_entity_types', array()))) {
    return array();
  }

  $entity_info = entity_get_info($entity_type);
  $translatable_bundle_types = array();

  foreach ($entity_info['bundles'] as $bundle_type => $bundle_definition) {

    if ($entity_type == 'comment') {
      $bundle_type = str_replace('comment_node_', '', $bundle_type);
      if (variable_get('language_content_type_' . $bundle_type) == ENTITY_TRANSLATION_ENABLED) {
        $translatable_bundle_types[$bundle_type] = $bundle_definition['label'];
      }
    }
    elseif ($entity_type == 'node') {
      if (variable_get('language_content_type_' . $bundle_type) == ENTITY_TRANSLATION_ENABLED) {
        $translatable_bundle_types[$bundle_type] = $bundle_definition['label'];
      }
    }
    else {
      $translatable_bundle_types[$bundle_type] = $bundle_definition['label'];
    }
  }

  return $translatable_bundle_types;
}

/**
 * Gets translatable entities of a given type.
 *
 * Additionally you can specify entity property conditions, pager and limit.
 *
 * @param string $entity_type
 *   Drupal entity type.
 * @param array $property_conditions
 *   Entity properties. There is no value processing so caller must make sure
 *   the provided entity property exists for given entity type and its value
 *   is processed.
 * @param bool $pager
 *   Flag to determine if pager will be used.
 *
 * @return array
 *   Array of translatable entities.
 */
function tmgmt_entity_get_translatable_entities($entity_type, $property_conditions = array(), $pager = FALSE) {

  if (!in_array($entity_type, variable_get('entity_translation_entity_types', array()))) {
    return array();
  }

  $languages = drupal_map_assoc(array_keys(language_list()));

  $entity_info = entity_get_info($entity_type);
  $label_key = isset($entity_info['entity keys']['label']) ? $entity_info['entity keys']['label'] : NULL;

  $id_key = $entity_info['entity keys']['id'];
  $query = db_select($entity_info['base table'], 'e');
  $query->addTag('tmgmt_entity_get_translatable_entities');
  $query->addField('e', $id_key);

  // Language neutral entities are not translatable. Filter them out. To do
  // that: join {entity_translation} table, but only records with source column
  // empty. The {entity_translation}.language will represent the original entity
  // language in that case.
  $source_table_alias = $query->leftJoin('entity_translation', NULL, "%alias.entity_type = :entity_type AND %alias.entity_id = e.$id_key AND %alias.source = ''", array(':entity_type' => $entity_type));
  $query->condition("$source_table_alias.language", LANGUAGE_NONE, '<>');

  // Searching for sources with missing translation.
  if (!empty($property_conditions['target_status']) && !empty($property_conditions['target_language']) && in_array($property_conditions['target_language'], $languages)) {

    $translation_table_alias = db_escape_field('et_' . $property_conditions['target_language']);
    $query->leftJoin('entity_translation', $translation_table_alias, "%alias.entity_type = :entity_type AND %alias.entity_id = e.$id_key AND %alias.language = :language",
        array(':entity_type' => $entity_type, ':language' => $property_conditions['target_language']));

    // Exclude entities with having source language same as the target language
    // we search for.
    $query->condition('e.language', $property_conditions['target_language'], '<>');

    if ($property_conditions['target_status'] == 'untranslated_or_outdated') {
      $or = db_or();
      $or->isNull("$translation_table_alias.language");
      $or->condition("$translation_table_alias.translate", 1);
      $query->condition($or);
    }
    elseif ($property_conditions['target_status'] == 'outdated') {
      $query->condition("$translation_table_alias.translate", 1);
    }
    elseif ($property_conditions['target_status'] == 'untranslated') {
      $query->isNull("$translation_table_alias.language");
    }
  }

  // Remove the condition so we do not try to add it again below.
  unset($property_conditions['target_language']);
  unset($property_conditions['target_status']);

  // Searching for the source label.
  if (!empty($label_key) && isset($property_conditions[$label_key])) {
    $search_tokens = explode(' ', $property_conditions[$label_key]);
    $or = db_or();

    foreach ($search_tokens as $search_token) {
      $search_token = trim($search_token);
      if (strlen($search_token) > 2) {
        $or->condition($label_key, "%$search_token%", 'LIKE');
      }
    }

    if ($or->count() > 0) {
      $query->condition($or);
    }

    unset($property_conditions[$label_key]);
  }

  // Searching by taxonomy bundles - we need to switch to vid as the bundle key.
  if ($entity_type == 'taxonomy_term' && !empty($property_conditions['vocabulary_machine_name'])) {
    $property_name = 'vid';
    $vocabulary = taxonomy_vocabulary_machine_name_load($property_conditions['vocabulary_machine_name']);
    $property_value = $vocabulary->vid;
    $query->condition('e.' . $property_name, $property_value);
    // Remove the condition so we do not try to add it again below.
    unset($property_conditions['vocabulary_machine_name']);
  }
  // Searching by the node bundles - that applies for node entities as well as
  // comment.
  elseif (in_array($entity_type, array('comment', 'node'))) {
    $node_table_alias = 'e';

    // For comments join node table so that we can filter based on type.
    if ($entity_type == 'comment') {
      $query->join('node', 'n', 'e.nid = n.nid');
      $node_table_alias = 'n';
    }

    // Get translatable node types and check if it is worth to continue.
    $translatable_node_types = array_keys(tmgmt_entity_get_translatable_bundles('node'));
    if (empty($translatable_node_types)) {
      return array();
    }

    // If we have type property add condition.
    if (isset($property_conditions['type'])) {
      $query->condition($node_table_alias . '.type', $property_conditions['type']);
      // Remove the condition so we do not try to add it again below.
      unset($property_conditions['type']);
    }
    // If not, query db only for translatable node types.
    else {
      $query->condition($node_table_alias . '.type', $translatable_node_types);
    }
  }

  // Add remaining query conditions which are expected to be handled in a
  // generic way.
  foreach ($property_conditions as $property_name => $property_value) {
    $query->condition('e.' . $property_name, $property_value);
  }

  if ($pager) {
    $query = $query->extend('PagerDefault')->limit(variable_get('tmgmt_source_list_limit', 20));
  }
  else {
    $query->range(0, variable_get('tmgmt_source_list_limit', 20));
  }

  $query->orderBy($entity_info['entity keys']['id'], 'DESC');
  $entity_ids = $query->execute()->fetchCol();
  $entities = array();

  if (!empty($entity_ids)) {
    $entities = entity_load($entity_type, $entity_ids);
  }

  return $entities;
}

/**
 * Implements hook_tmgmt_source_suggestions()
 */
function tmgmt_entity_tmgmt_source_suggestions(array $items, TMGMTJob $job) {
  $suggestions = array();
  // Get all translatable entity types.
  $entity_types = array_filter(variable_get('entity_translation_entity_types', array()));

  foreach ($items as $item) {
    if (($item instanceof TMGMTJobItem) && ($item->plugin == 'entity') || ($item->plugin == 'node')) {
      // Load the entity and extract the bundle name to get all fields from the
      // current entity.
      $entity = entity_load_single($item->item_type, $item->item_id);
      list(, , $bundle) = entity_extract_ids($item->item_type, $entity);
      $field_instances = field_info_instances($item->item_type, $bundle);


      // Loop over all fields, check if they are NOT translatable. Only if a
      // field is not translatable we may suggest a referenced entity. If so,
      // check for a supported field type (image and file currently here).
      foreach ($field_instances as $instance) {
        $field = field_info_field($instance['field_name']);
        $field_type = $field['type'];
        $field_name = $field['field_name'];
        switch ($field_type) {
          case 'file':
          case 'image':
            // 'File' (and images) must be translatable entity types.
            // Other files we not suggest here. Get all field items from the
            // current field and suggest them as translatable.
            if (isset($entity_types['file']) && ($field_items = field_get_items($item->item_type, $entity, $field_name))) {
              // Add all files as a suggestion.
              foreach ($field_items as $field_item) {
                $file_entity = entity_load_single('file', $field_item['fid']);

                // Check if there is already a translation available for this
                // file. If so, just continue with the next file.
                $handler = entity_translation_get_handler('file', $file_entity);
                if ($handler instanceof EntityTranslationHandlerInterface) {
                  $translations = $handler->getTranslations();
                  if (isset($translations->data[$job->target_language])) {
                    continue;
                  }
                }

                // Add the translation as a suggestion.
                $suggestions[] = array(
                  'job_item' => tmgmt_job_item_create('entity', 'file', $file_entity->fid),
                  'reason' => t('Field @label', array('@label' => $instance['label'])),
                  'from_item' => $item->tjiid,
                );
              }
            }
            break;

          case 'entityreference':
            $target_type = $field['settings']['target_type'];
            // Make sure only tranlatable entity types are suggested.
            if (isset($entity_types[$target_type]) && ($field_items = field_get_items($item->item_type, $entity, $field_name))) {
              // Add all referenced entities as suggestion.
              foreach ($field_items as $field_item) {
                $ref_entity = entity_load_single($target_type, $field_item['target_id']);

                // Check if there is already a translation available for this
                // entity. If so, just continue with the next one.
                $handler = entity_translation_get_handler($target_type, $ref_entity);
                if ($handler instanceof EntityTranslationHandlerInterface) {
                  $translations = $handler->getTranslations();
                  if (isset($translations->data[$job->target_language])) {
                    continue;
                  }
                }

                // Add suggestion.
                $suggestions[] = array(
                  'job_item' => tmgmt_job_item_create('entity', $target_type, $field_item['target_id']),
                  'reason' => t('Field @label', array('@label' => $instance['label'])),
                  'from_item' => $item->tjiid,
                );
              }
            }
            break;
        }
      }
    }
  }
  return $suggestions;
}