Club Drupal

<?php

/**

 * @file

 * Includes the hooks defined by diff_hook_info().

 */

/**

 * Implements hook_entity_diff().

 *

 * Helper function to invoke the depreciated hook_diff() for node entities.

 *

 * This manually invokes hook_diff() to avoid a function name clash with the

 * PHP 5 (>= 5.3.0) date_diff() function or the Dates modules implementation.

 */

function diff_entity_diff($old_entity, $new_entity, $context) {

  $return = array();

  $entity_type = $context['entity_type'];

  $info = entity_get_info($entity_type);

  if (!empty($info['fieldable'])) {

    $return = diff_entity_fields_diff($old_entity, $new_entity, $context);

  }

  return $return;

}

/**

 * Internal callback to handle fieldable entities.

 *

 * Field comparison is handled for core modules, but is expandable to any other

 * fields if the module defines MODULE_field_diff_view().

 *

 * @param object $old_entity

 *   The older entity entity revision.

 * @param object $new_entity

 *   The newer entity entity revision.

 * @param array $context

 *   An associative array containing:

 *   - entity_type: The entity type; e.g., 'node' or 'user'.

 *   - old_entity: The older entity.

 *   - new_entity: The newer entity.

 *   - view_mode: The view mode to use. Defaults to FALSE.

 * @param string $default_langcode

 *   (optional) Language code to force comparison in.

 *

 * @return array

 *   An associative array of values keyed by the field name and delta value.

 */

function diff_entity_fields_diff($old_entity, $new_entity, $context, $default_langcode = NULL) {

  $result = array();

  $entity_type = $context['entity_type'];

  $view_mode = $context['view_mode'];

  $field_context = $context;

  $actual_mode = FALSE;

  list(, , $bundle_name) = entity_extract_ids($entity_type, $new_entity);

  $instances = field_info_instances($entity_type, $bundle_name);

  // Some fields piggy back the display settings, so we need to fake these by

  // ensuring that the field mode is always set.

  if (empty($view_mode)) {

    $actual_mode = 'diff_standard';

    $field_context['custom_settings'] = FALSE;

  }

  $view_mode_settings = field_view_mode_settings($entity_type, $bundle_name);

  $actual_mode = (!empty($view_mode_settings[$view_mode]['custom_settings'])) ? $view_mode : 'default';

  if (!isset($field_context['custom_settings'])) {

    $field_context['custom_settings'] = $actual_mode && $actual_mode == $view_mode;

  }

  $field_context['old_entity'] = $old_entity;

  $field_context['new_entity'] = $new_entity;

  $field_context['bundle_name'] = $bundle_name;

  foreach ($instances as $instance) {

    // Any view mode is supported in relation to hiding fields, but only if

    // selected (todo see if this is a valid option).

    if ($actual_mode && $instance['display'][$actual_mode]['type'] == 'hidden') {

      continue;

    }

    $field_name = $instance['field_name'];

    $field = field_info_field($field_name);

    $field_context['field'] = $field;

    $field_context['instance'] = $instance;

    $field_context['display'] = $instance['display'][$actual_mode];

    // We provide a loose check on the field access.

    if (field_access('view', $field, $entity_type) || field_access('edit', $field, $entity_type)) {

      $langcode = $default_langcode ? $default_langcode : field_language($entity_type, $new_entity, $field_name);

      $field_context['language'] = $langcode;

      $field_context['field'] = $field;

      $field_context['instance'] = $instance;

      $old_items = array();

      if (!empty($old_entity->{$field_name}[$langcode])) {

        $old_items = $old_entity->{$field_name}[$langcode];

      }

      $new_items = array();

      if (!empty($new_entity->{$field_name}[$langcode])) {

        $new_items = $new_entity->{$field_name}[$langcode];

      }

      // Load files containing the field callbacks.

      _diff_autoload($field);

      $field_context['settings'] = diff_get_field_settings($field_context);

      // Reference fields can optionally prepare objects in bulk to reduce

      // overheads related to multiple database calls. If a field considers

      // that the delta values is meaningless, they can order and rearrange

      // to provide cleaner results.

      $func = $field['module'] . '_field_diff_view_prepare';

      if (function_exists($func)) {

        $func($old_items, $new_items, $field_context);

      }

      // Allow other modules to act safely on behalf of the core field module.

      drupal_alter('field_diff_view_prepare', $old_items, $new_items, $field_context);

      // These functions compiles the items into comparable arrays of strings.

      $func = $field['module'] . '_field_diff_view';

      if (!function_exists($func)) {

        $func = 'diff_field_diff_view';

      }

      // Copy the static ID cache to ensure this is the same for each comparison.

      $original_html_ids = drupal_static('drupal_html_id');

      $html_ids = &drupal_static('drupal_html_id');

      // These callbacks should be independent of revision.

      $old_context = $field_context;

      $old_context['entity'] = $old_entity;

      $old_values = $func($old_items, $old_context);

      // Restores the ID cache to the original.

      $html_ids = $original_html_ids;

      $new_context = $field_context;

      $new_context['entity'] = $new_entity;

      $new_values = $func($new_items, $new_context);

      // Allow other modules to act safely on behalf of the core field module.

      drupal_alter('field_diff_view', $old_values, $old_items, $old_context);

      drupal_alter('field_diff_view', $new_values, $new_items, $new_context);

      $max = max(array(count($old_values), count($new_values)));

      if ($max) {

        $result[$field_name] = array(

          '#name' => $instance['label'],

          '#old' => array(),

          '#new' => array(),

          '#settings' => $field_context['settings'],

        );

        for ($delta = 0; $delta < $max; $delta++) {

          if (isset($old_values[$delta])) {

            $result[$field_name]['#old'][] = is_array($old_values[$delta]) ? implode("\n", $old_values[$delta]) : $old_values[$delta];

          }

          if (isset($new_values[$delta])) {

            $result[$field_name]['#new'][] = is_array($new_values[$delta]) ? implode("\n", $new_values[$delta]) : $new_values[$delta];

          }

        }

        $result[$field_name]['#old'] = implode("\n", $result[$field_name]['#old']);

        $result[$field_name]['#new'] = implode("\n", $result[$field_name]['#new']);

        if ($actual_mode) {

          $result[$field_name]['#weight'] = $instance['display'][$actual_mode]['weight'];

        }

      }

    }

  }

  return $result;

}

/**

 * A generic handler for parsing field values.

 *

 * This callback can only handle the most basic of fields that populates the

 * safe_value during field load or use the value column for data storage.

 *

 * @param array $items

 *   An array of field items.

 * @param array $context

 *   An associative array containing:

 *   - entity: The entity that the items belong to.

 *   - entity_type: The entity type; e.g., 'node' or 'user'.

 *   - bundle: The bundle name.

 *   - field: The field that the items belong to.

 *   - instance: The instance that the items belong to.

 *   - language: The language associated with $items.

 *   - old_entity: The older entity.

 *   - new_entity: The newer entity.

 *

 * @return array

 *   An array of strings representing the value, keyed by delta index.

 */

function diff_field_diff_view($items, $context) {

  // Prevent unnecessary rendering of the field. This also prevents issues

  // where field_view_field() will use a language fallback for display that

  // may not match the requested diff comparison language.

  if (!$items) {

    return array();

  }

  $diff_items = array();

  $entity = clone $context['entity'];

  $langcode = field_language($context['entity_type'], $entity, $context['field']['field_name']);

  $view_mode = empty($context['view_mode']) ? 'diff_standard' : $context['view_mode'];

  $element = field_view_field($context['entity_type'], $entity, $context['field']['field_name'], $view_mode, $langcode);

  foreach (element_children($element) as $delta) {

    $diff_items[$delta] = drupal_render($element[$delta]);

  }

  return $diff_items;

}

/**

 * Helper function to get the settings for a given field or formatter.

 *

 * @param array $field_context

 *   This will get the settings for a field.

 *   - field (required): The field that the items belong to.

 *   - entity: The entity that we are looking up.

 *   - instance: The instance that the items belong to.

 *   - view_mode: The view mode to use. Defaults to FALSE.

 *

 * @return array

 *   The settings for this field type.

 */

function diff_get_field_settings($field_context) {

  $field = $field_context['field'];

  // Update saved settings from the global settings for this field type.

  $settings = variable_get("diff_{$field['module']}_field_{$field['type']}_default_options", array());

  $settings = _diff_field_default_settings($field['module'], $field['type'], $settings);

  // Allow modules to alter the field settings based on the current context.

  drupal_alter('diff_field_settings', $settings, $field_context);

  return $settings;

}

/**

 * Helper function to initiate any global form elements.

 */

function diff_global_settings_form(&$subform, $form_state, $type, $settings) {

  $subform['show_header'] = array(

    '#type' => 'checkbox',

    '#title' => t('Show field title'),

    '#default_value' => $settings['show_header'],

    '#weight' => -5,

  );

  $subform['markdown'] = array(

    '#type' => 'select',

    '#title' => t('Markdown callback'),

    '#default_value' => $settings['markdown'],

    '#options' => array(

      'drupal_html_to_text' => t('Drupal HTML to Text'),

      'filter_xss' => t('Filter XSS (some tags)'),

      'diff_filter_xss' => t('Filter XSS (all tags)'),

    ),

    '#description' => t('These provide ways to clean markup tags to make comparisons easier to read.'),

    '#empty_option' => t('- Do not process -'),

  );

  $subform['line_counter'] = array(

    '#type' => 'radios',

    '#title' => t('Line counter'),

    '#default_value' => $settings['line_counter'],

    '#description' => t('This outputs the (approximate) line numbers as a heading before every change.'),

    '#options' => array(

      '' => t('None. Counter ignore and not incremented.'),

      'hidden' => t('Count lines but do not show line headers.'),

      'line' => t('Count and show lines, restarting counter at 0.'),

      'line_continuous' => t('Count and show lines, incrementing counter from last item.'),

    ),

  );

}

/**

 * Helper function to populate the settings array.

 */

function _diff_field_default_settings($module, $field_type, $settings = array()) {

  // Load files containing the field callbacks.

  _diff_autoload($module);

  // Populate any missing values from CALLBACK_field_diff_default_options().

  $func = $module . '_field_diff_default_options';

  if (function_exists($func)) {

    $settings += $func($field_type);

  }

  // Check for Diff support. If it doesn't exist, the default markdown should

  // escape the field display, otherwise a raw format should be used.

  $func = $module . '_field_diff_view';

  // Global settings.

  $settings += array(

    'markdown' => function_exists($func) ? '' : 'drupal_html_to_text',

    'line_counter' => '',

    'show_header' => 1,

  );

  return $settings;

}

/**

 * Private helper function to load field includes.

 *

 * @param array|string $field_or_module

 *   The field definition array or the module that implements the field.

 */

function _diff_autoload($field_or_module) {

  $includes = &drupal_static(__FUNCTION__, FALSE);

  if (!$includes) {

    $includes = array(

      'file' => module_exists('file'),

      'image' => module_exists('image'),

      'list' => module_exists('list'),

      'taxonomy' => module_exists('taxonomy'),

      'text' => module_exists('text'),

      'number' => module_exists('number'),

    );

  }

  $module = is_string($field_or_module) ? $field_or_module : $field_or_module['module'];

  // Since field hooks are not real hooks, we manually load the field modules

  // MODULE.diff.inc. We handle the five core field defining modules.

  if (!isset($includes[$module])) {

    module_load_include('diff.inc', $module);

    $includes[$module] = 0;

  }

  elseif (!empty($includes[$module])) {

    module_load_include('inc', 'diff', 'includes/' . $module);

    $includes[$module] = 0;

  }

}

/**

 * Helper function to parse out the state in the diff results.

 */

function diff_extract_state($diff, $state = 'raw') {

  $states = array(

    0 => NULL,

    1 => NULL,

  );

  if (isset($diff['#states'][$state])) {

    if (isset($diff['#states'][$state]['#old'])) {

      $states[0] = $diff['#states'][$state]['#old'];

    }

    if (isset($diff['#states'][$state]['#new'])) {

      $states[1] = $diff['#states'][$state]['#new'];

    }

  }

  return $states;

}