<?php
/**
 * @file
 * Main file for linkit module.
 */

/**
 * The default weight for attributes and plugins.
 */
define('LINKIT_DEFAULT_WEIGHT', 0);

/**
 * The default profile machine name
 */
define('LINKIT_DEFAULT_PROFILE_MACHINE_NAME', 'default');

// Include the file with the field UI functions.
require_once dirname(__FILE__) . '/linkit.field.inc';


/**
 * Implements hook_menu().
 */
function linkit_menu() {
  $items = array();

  $items['linkit/dashboard/%'] = array(
    'title' => 'Linkit',
    'description' => 'Dashboard',
    'page callback' => '_linkit_dashboard',
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK,
    'page arguments' => array(2),
    'theme callback' => '_linkit_dashboard_theme',
  );

  $items['linkit/autocomplete'] = array(
    'title' => 'Linkit autocomplete response function',
    'page callback' => '_linkit_autocomplete',
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK,
  );

  $items['admin/config/content/linkit/reorder'] = array(
    'title' => 'Reorder',
    'description' => 'Reorder Linkit profiles',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('linkit_profiles_reorder'),
    'access arguments' => array('administer linkit'),
    'file path' => drupal_get_path('module', 'linkit') . '/plugins/export_ui',
    'file' => 'linkit_profiles.inc',
    'type' => MENU_LOCAL_TASK,
  );

  return $items;
}

/**
 * Implements hook_menu_alter().
 */
function linkit_menu_alter(&$items) {
  // Override the default titles that ctools export_ui sets.
  // This way there is less code compared to define this in the plugin array.
  $items['admin/config/content/linkit/add']['title'] = 'Add new profile';
  $items['admin/config/content/linkit/import']['title'] = 'Import profiles';

  // Make tabs
  $items['admin/config/content/linkit/add']['type'] = MENU_LOCAL_TASK;
  $items['admin/config/content/linkit/import']['type'] = MENU_LOCAL_TASK;
}

/**
 * Return the theme name to be used when showing linkit dashboard
 */
function _linkit_dashboard_theme() {
  return variable_get('admin_theme', 'seven');
}

/**
 * Implements hook_permission().
 */
function linkit_permission() {
  $permissions = array();
  $permissions['administer linkit'] = array(
    'title' => t('Administer Linkit'),
    'description' => t('Perform administration tasks for Linkit.'),
  );

  return $permissions;
}

/**
 * Implements hook_theme().
 */
function linkit_theme($existing, $type, $theme, $path) {
  return array(
    'linkit_profiles_export_ui_form' => array(
      'render element' => 'form',
      'file' => 'linkit.theme.inc',
    ),
    'linkit_profiles_reorder' => array(
      'render element' => 'form',
      'file' => 'linkit.theme.inc'
    ),
    '_linkit_theme_profile_form_table' => array(
      'variables' => array(),
      'file' => 'linkit.theme.inc'
    ),
    'linkit_reverse_menu_trail' => array(
      'variables' => array('menu_trail' => NULL, 'separator' => ' « '),
      'file' => 'linkit.theme.inc'
    )
  );
}

/**
 * Implements hook_element_info_alter().
 */
function linkit_element_info_alter(&$types) {
  if (isset($types['text_format']['#pre_render']) && is_array($types['text_format']['#pre_render'])) {
    if (in_array('ckeditor_pre_render_text_format', $types['text_format']['#pre_render'])) {
      $types['text_format']['#pre_render'][] = 'linkit_pre_render_ckeditor_element';
    }
  }
  // Append a process function for the field integration.
  foreach (linkit_allowed_elements() as $element) {
    if (isset($types[$element])) {
      $types[$element]['#process'][] = 'linkit_process_widget';
    }
  }
}

/**
 * Add Linkit settings to pages where we have a ckeditor element.
 */
function linkit_pre_render_ckeditor_element($element) {
  _linkit_add_settings('ckeditor');
  return $element;
}

/**
 * Implements hook_ckeditor_plugin().
 */
function linkit_ckeditor_plugin() {
  return array(
    'linkit' => array(
      // Name of the plugin used to write it
      'name' => 'linkit',
      // Description of plugin - it would appear in plugins managment of profile settings
      'desc' => t('Support for Linkit module'),
      // The full path to the CKEditor plugin directory, with trailing slash.
      'path' => drupal_get_path('module', 'linkit') . '/editors/ckeditor/',
      // Buttons to show up in the toolbar config area.
      'buttons' => array(
        'linkit' => array(
          'label' => 'Linkit',
          'icon' => 'linkit.png',
        ),
      ),
    ),
  );
}

/**
 * Implements hook_library().
 */
function linkit_library() {
  $path = drupal_get_path('module', 'linkit');

  $common = array(
    'website' => 'http://drupal.org/project/linkit',
    'version' => '7.2',
  );

  // Better Autocomplete
  $libraries['linkit_bac'] = array(
    'title' => 'Linkit Better Autocomplete',
    'js' => array(
      $path . '/better-autocomplete/jquery.better-autocomplete.js' => array('group' => JS_LIBRARY),
      array(
        'type' => 'setting',
        'data' => array('linkit' => array('autocompletePath' => url('linkit/autocomplete', array('query' => array('s' => ''), 'absolute' => TRUE)))),
      ),
    ),
    'css' => array(
      $path . '/better-autocomplete/better-autocomplete.css' => array('group' => CSS_DEFAULT),
    ),
  );

  // Linkit base
  $libraries['linkit_base'] = array(
    'title' => 'Linkit base',
    'js' => array(
      $path . '/js/linkit.js' => array('group' => JS_DEFAULT),
      $path . '/js/linkit.dialog.js' => array('group' => JS_DEFAULT),
      // Add global settings for Linkit
      array(
        'type' => 'setting',
        'data' => array('linkit' => array('modulepath' => drupal_get_path('module', 'linkit'))),
      ),
    ),
    'css' => array(
      $path . '/css/linkit.css' => array('group' => CSS_DEFAULT),
    ),
    'dependencies' => array(
      array('system', 'ui.dialog'),
      array('system', 'drupal.collapse'),
      array('linkit', 'linkit_bac'),
    ),
  );

  // Linkit ckeditor dialog script.
  $libraries['linkit_ckeditor'] = array(
    'title' => 'Linkit CKeditor',
    'js' => array(
      $path . '/editors/ckeditor/linkitDialog.js' => array('group' => JS_DEFAULT),
    ),
  );

  // Linkit tinymce dialog script.
  $libraries['linkit_tinymce'] = array(
    'title' => 'Linkit TinyMCE',
    'js' => array(
      $path . '/editors/tinymce/linkitDialog.js' => array('group' => JS_DEFAULT),
    ),
  );

  // Linkit field ui script.
  $libraries['linkit_field'] = array(
    'title' => 'Linkit Field UI',
    'js' => array(
      $path . '/js/linkit.field.js' => array('group' => JS_DEFAULT),
      $path . '/js/linkitFieldDialog.js' => array('group' => JS_DEFAULT),
    ),
    'dependencies' => array(
      array('linkit', 'linkit_base'),
    ),
  );

  foreach ($libraries as &$library) {
    $library += $common;
  }

  return $libraries;
}

/**
 * Creates the dashboard.
 */
function _linkit_dashboard($editor) {
  $form = drupal_get_form('linkit_dashboard_form');
  print drupal_render($form);
  drupal_exit();
}

/**
 * Autocomplete callback function.
 */
function _linkit_autocomplete($search = NULL) {
  $search = $_GET['s'];
  $enabled_plugins = linkit_get_profile_plugins();

  // Absolute URL
  if ($result = _linkit_result_from_url($search, $enabled_plugins)) {
    $results = array($result);
  }
  elseif (!$results = _linkit_autocomplete_search($search, $enabled_plugins)) {
    $results = array(array(
      'title' => t('No results'),
      'addClass' => 'status-notice',
      'disabled' => TRUE,
    ));
  }
  drupal_json_output($results);
  drupal_exit();
}

/**
 * Perform internal autocomplete search.
 *
 * @param $search_string
 *   The search string.
 * @return $results
 *   An array with the result objects.
 */
function _linkit_autocomplete_search($search_string, $enabled_plugins) {
  $matches = array();
  if ($search_string) {
    $profile = linkit_get_dashboard_profile();

    foreach ($enabled_plugins as $plugin) {
      // Get an instance of the handler for this plugin.
      $handler = linkit_get_plugin_handler($plugin, $profile);
      // If the handler is broken, just continue.
      if ($handler->broken()) {
        continue;
      }
      // Add the search string.
      $handler->setSearchString($search_string);
      // Call the plugin search metod.
      $results = $handler->autocomplete_callback();
      // Merge the results.
      $matches = array_merge($matches, $results);
    }
    // Special for link to frontpage.
    if (strpos($search_string, 'front') !== FALSE) {
      $results = array(
        array(
          'title' => t('Frontpage'),
          'description' => 'The frontpage for this site.',
          'path' => url('<front>'),
          'group' => t('System'),
        )
      );
      $matches = array_merge($matches, $results);
    }
  }
  if (!empty($matches)) {
    return $matches;
  }
  return FALSE;
}

/**
 * Retrieve relevant information about a URL. Specifically this function is
 * usable for internal (absolute) URL:s, but it also works for external URL:s.
 *
 * @param $url
 *   The url that should be scanned.
 *
 * @return $path_info
 *   An associative array containing:
 *   - url: The same as the argument $url, untouched.
 *   - target: Either "internal" or "external".
 *   - requested_path: If internal, the path requested relative to Drupal root.
 *     The only exception is when frontpage is referred directly, then it will
 *     be whatever the frontpage is set to.
 *   - system_path: If internal and the path is valid, the Drupal system path,
 *     e.g. "node/23".
 *   - query_fragment: If internal, the query and fragment of the url.
 *     Typically it is not needed for searching and is just reappended back
 *     when processing of the path is done. It could e.g. look like
 *     "?foo=bar#anchor".
 *   - safe_url: If external, and the protocol is http or https, this will be
 *     the original url, stripped from everything that could potentially be
 *     dangerous. E.g. "http://user:pass@example.org/settings?evilaction=true"
 *     will become "http://example.org/settings".
 */
function linkit_scan_url($url) {
  global $base_url;
  // We will not use the drupal wrapper function 'drupal_pasre_url' as that
  // function should only be used for URLs that have been generated by the
  // system, and we cant be sure that this is the case here.
  $parts = parse_url(trim($url, '/'));
  if (!isset($parts['scheme']) || !isset($parts['host'])) {
    // Not an absolute URL.
    return FALSE;
  }

  // Make a new array, this will hold the components from parse_url() and our
  // own "Linkit" components.
  $path_info = array();

  // Append the original components from parse_url() to our array.
  $path_info += $parts;

  // Save the whole URL.
  $path_info['url'] = $url;

  if (!isset($path_info['query'])) {
    $path_info['query'] ='';
  }

  // Convert the query string to an array as Drupal can only handle querys as
  // arrays.
  // @see http://api.drupal.org/drupal_http_build_query
  parse_str($path_info['query'], $path_info['query']);

  // The 'q' parameter contains the path of the current page if clean URLs are
  // disabled. It overrides the 'path' of the URL when present, even if clean
  // URLs are enabled, due to how Apache rewriting rules work.
  if (isset($path_info['query']['q'])) {
    $path_info['path'] = $path_info['query']['q'];
    unset($path_info['query']['q']);
  }

  // Internal URL.
  // @TODO: Handle https and other schemes here?
  if (trim($path_info['scheme'] . '://' . $path_info['host'] . base_path(), '/') == $base_url) {
    $path_info['target'] = 'internal';

    // Remove the subdirectory name from the path if the site is installed in
    // subdirectory. It will be added again by the url() function.
    if (base_path() != "/") {
      $path_info['path'] = trim(preg_replace(base_path(), '', $path_info['path'], 1), '/');
    }

    // Trim the path from slashes.
    $path_info['path'] = trim($path_info['path'], '/');

    // If we have an empty path, and an internal target, we can assume that the
    // URL should go the the frontpage.
    if (empty($path_info['path'])) {
      $path_info['frontpage'] = TRUE;
      $path_info['path'] = variable_get('site_frontpage', 'node');
    }

    // Check if the path already is an alias.
    if (!$processed_path = drupal_lookup_path('source', $path_info['path'])) {
      // Not an alias, so keep the original value.
      $processed_path = $path_info['path'];
    }
    // Add the "real" system path (not the alias) if the current user have
    // access to the URL.
    $path_info['system_path'] = drupal_valid_path($processed_path) ? $processed_path : FALSE;
  }
  // External URL
  else {
    $path_info['target'] = 'external';
    if (preg_match('~^https?$~', $parts['scheme'])) {
      $path_info['safe_url'] = $parts['scheme'] . '://' . $parts['host'] . $parts['path'];
    }
  }

  return $path_info;
}

/**
 * Retrieve the result object from an absolute URL. This function calls the
 * enabled plugins' "path info callback" to look for a result object. Both
 * internal and external paths work.
 *
 * @param $url
 *   An absolute URL.
 *
 * @return
 *   A result object. This is an associative array which consists of:
 *   - title: The title of the result
 *   - description: The description of the result (may contain HTML).
 *   - path: The target path which will be inserted as the href in the link.
 *   - addClass: A CSS class that will be added to the DOM result item.
 */
function _linkit_result_from_url($url, $enabled_plugins) {
  if (!$path_info = linkit_scan_url($url)) {
    return FALSE;
  }

  // Do we have Clean URLS activated.
  $clean_urls = !empty($GLOBALS['conf']['clean_url']);

  // Set default options to pass with the url() function.
  $url_options = array(
    'alias' => TRUE,
  );

  // Add the URL frament.
  $url_options['fragment'] = isset($path_info['fragment']) ? $path_info['fragment'] : '';
  // Add the URL query.
  $url_options['query'] = isset($path_info['query']) ? $path_info['query'] : '';

  $result = array();

  if (isset($path_info['system_path']) && (bool) $path_info['system_path']) {
    $menu_item = menu_get_item($path_info['system_path']);
    $result = array(
      'path' => url($path_info['system_path'], $url_options),
      'title' => $menu_item['title'] ? check_plain($menu_item['title']) : check_plain($path_info['system_path']),
      'description' => t('This is an internal path.'),
      'addClass' => 'status-ok',
    );
  }
  // No plugin result, but the URL seems to be internal. Either we do not have
  // access to it or it does not exists.
  elseif ($path_info['target'] == 'internal') {
    $result = array(
      'path' => url($path_info['path'], $url_options),
      'title' => t('Page not found'),
      'description' => t('This page does not exist or you do not have access to it.'),
      'addClass' => 'status-warning',
    );
  }
  // No plugin result, and the URL seems to be external.
  elseif ($path_info['target'] == 'external') {
    $result = array(
      'title' => t('No information available'),
      'description' => t("This is an external URL, but we don't know where it leads."),
      'path' => $path_info['url'],
      'addClass' => 'status-notice',
    );
  }

  return $result;
}

/**
 * Implements hook_form().
 */
function linkit_dashboard_form($form, &$form_state) {
  $profile = linkit_get_dashboard_profile();

  // If we do not have a Linkit profile, lets show the user a message.
  if (is_null($profile)) {
    drupal_set_message(t('There is no Linkit profile associated with your role.'), 'warning');
    $form['message'] = array(
      '#markup' => theme('status_messages') . '<a id="linkit-cancel" href="#">' . t('Close') . '</a>',
    );
    return $form;
  }

  $form['linkit_search'] = array(
    '#type' => 'textfield',
    '#title' => t('Search content'),
    '#description' => t('Start typing to find content or paste a URI. Use the arrow keys to navigate.'),
    '#maxlength' => 255,
    '#size' => 60,
    '#default_value' => '',
    '#weight' => -10,
  );

  // The IMCE button is generated with JavaScript, see linkit.js.

  $form['linkit_path'] = array(
    '#type' => 'textfield',
    '#title' => t('Target path'),
    '#description' => t('Examples: <strong>node/123</strong>, <strong>http://www.example.com/path#anchor</strong>'),
    '#required' => TRUE,
    '#maxlength' => NULL,
    '#size' => 60,
    '#default_value' => '',
    '#weight' => -1,
  );

  $enabled_attributes = linkit_get_profile_attributes();

  // If we have enabled attributes, lets put them inside a fieldset.
  if (count($enabled_attributes)) {
    // Create the container fieldset.
    $form['linkit_attributes'] = array(
      '#type' => 'fieldset',
      '#title' => t('Attributes'),
      '#collapsible' => TRUE,
      '#collapsed' => TRUE,
      '#weight' => 10,
    );
    // Append the attributes info the fieldset.
    foreach ($enabled_attributes AS $name => $attribute) {
      // Add 'linkit_' prefix to ensure that is uniq.
      $form['linkit_attributes']['linkit_' . $name] = $attribute;
    }
  }

  $form['linkit_insert'] = array(
    '#type' => 'button',
    '#value' => t('Insert link'),
    '#suffix' => '<a id="linkit-cancel" href="#">' . t('Cancel') . '</a>',
    '#weight' => 100,
  );

  return $form;
}

/**
 * Implements hook_wysiwyg_plugin().
 */
function linkit_wysiwyg_plugin($editor, $version) {
  $plugin = array();
  _linkit_add_settings($editor);

  $plugin['linkit'] = array(
    'path' => drupal_get_path('module', 'linkit') . '/editors/' . $editor,
    'buttons' => array('linkit' => t('Linkit')),
    'url' => 'http://drupal.org/project/linkit',
    'load' => TRUE,
  );

  // TinyMCE needs to know the filename.
  if ($editor == 'tinymce') {
    $plugin['linkit']['filename'] = 'editor_plugin.js';
  }

  return $plugin;
}

/**
 *  Add necessary settings to the Drupal.settings array and include the
 * libraries we need.
 */
function _linkit_add_settings($editor) {
  static $globalsettings, $set_urls;
  drupal_add_library('linkit', 'linkit_base');
  $profile = linkit_get_dashboard_profile();

  if (!$globalsettings && $profile) {
    // Check if IMCE is enbled and accessable
    if (module_invoke('imce', 'access') && isset($profile->data['imce']['use_imce']) && $profile->data['imce']['use_imce'] == 1) {
      $settings['IMCEurl'] = url('imce', array('query' => array(
        'app' => 'Linkit|sendto@Drupal.linkit.dialog.IMCECallback',
        'absolute' => TRUE,
      )));
      // We will only serv public files with IMCE.
      $settings['publicFilesDirectory'] = variable_get('file_public_path', conf_path() . '/files');
    }

    $settings['autocomplete'] = array_filter($profile->data['autocomplete']);

    // Add caseSensitive
    $settings['autocomplete'] += array('caseSensitive' => TRUE);
    drupal_add_js(array('linkit' => $settings), 'setting');

    $globalsettings = TRUE;
  }

  if (!isset($set_urls[$editor])) {
    // Add dialog url for the editor.
    $settings = array(
      'linkit' => array('url' => array($editor => url('linkit/dashboard/' . $editor))),
    );
    drupal_add_js($settings, 'setting');
    $set_urls[$editor] = TRUE;
  }

  // Add the linkit library for the editor.
  drupal_add_library('linkit', 'linkit_' . $editor);
}

/**
 * Implements hook_help().
 */
function linkit_help($path, $arg) {
  switch ($path) {
    case 'admin/help#linkit':
      $output = file_get_contents(drupal_get_path('module', 'linkit') . '/README.txt');
      return nl2br($output);
  }
}

/**
 * Determines if a profile with a given name exists.
 *
 * @param $profile_name
 *   The ID of the profile check.
 * @return
 *   TRUE if the profile exists, FALSE otherwise.
 *
 * @see filter_format_load()
 */
function linkit_profile_exists($profile_name) {
  $profile = linkit_profile_load($profile_name);
  return is_object($profile);
}

/**
 * Implements hook_image_default_styles().
 *
 * @return
 *   An array of image styles, keyed by the style name.
 */
function linkit_image_default_styles() {
  $styles = array();

  $styles['linkit_thumb'] = array(
    'effects' => array(
      array(
        'name' => 'image_scale',
        'data' => array('width' => 50, 'height' => 50, 'upscale' => 0),
        'weight' => 0,
      ),
    ),
  );

  return $styles;
}

/**
 * Get all attributes defined by hook_linkit_attributes().
 */
function linkit_get_attributes($profile = NULL) {
  if (is_null($profile)) {
    $profile = linkit_get_dashboard_profile();
  }

  // Let other modules implement thier own attributes.
  $attributes = module_invoke_all('linkit_attributes', $profile);

  // Let other modules alter the attributes.
  drupal_alter('linkit_attributes', $attributes);

  return $attributes;
}

/**
 * Implements hook_linkit_attributes().
 *
 * Define them like form elements.
 */
function linkit_linkit_attributes($profile) {
  $attributes['accesskey'] = array(
    '#type' => 'textfield',
    '#title' => 'accesskey',
  );

  $attributes['class'] = array(
    '#type' => 'textfield',
    '#title' => 'class',
  );

  $attributes['id'] = array(
    '#type' => 'textfield',
    '#title' => 'id',
  );

  $attributes['rel'] = array(
    '#type' => 'textfield',
    '#title' => 'rel',
  );

  $attributes['title'] = array(
    '#type' => 'textfield',
    '#title' => 'title',
  );

  foreach ($attributes as $key => &$attribute) {
    $attribute += array(
      '#maxlength' => 255,
      '#size' => 40,
      '#default_value' => '',
      '#weight' => isset($profile->data['attributes'][$key]['weight']) ? $profile->data['attributes'][$key]['weight'] : 0,
    );
  }
  return $attributes;
}

/**
 * Get all enabled attributes for the profiles used on the dashboard.
 */
function linkit_get_profile_attributes() {
  $profile = linkit_get_dashboard_profile();
  $enabled_attributes = array();

  if (isset($profile->data['attributes'])) {
    // Loop thru all attributes and build an array with all that is enabled.
    foreach (linkit_get_attributes($profile) as $name => $attribute) {
      if (isset($profile->data['attributes'][$name]['enabled']) && $profile->data['attributes'][$name]['enabled']) {
        // Add Linkit specific class, this is used by the editor JS scripts.
        $attribute['#attributes']['class'][] = 'linkit-attribute';
        $enabled_attributes[$name] = $attribute;
      }
    }
  }
  return $enabled_attributes;
}

/**
 * Get all enabled plugins for the profiles used on the dashboard.
 */
function linkit_get_profile_plugins() {
  $installed_plugins = linkit_get_plugins();
  $profile = linkit_get_dashboard_profile();

  // We have no profile.
  if (is_null($profile)) {
    return array();
  }

  $enabled_plugins = array();

  foreach ($installed_plugins AS $name => $plugin) {
    if ($profile->data['plugins'][$name]['enabled']) {
      $enabled_plugins[$name] = $plugin;
    }
  }
  return $enabled_plugins;
}

/**
 * Fetch metadata for all linkit plugins.
 *
 * @return
 *   An array of arrays with information about all available linkit plugins.
 */
function linkit_get_plugins() {
  ctools_include('plugins');
  $plugins = ctools_get_plugins('linkit', 'linkit_plugins');
  // If you alter the plugins handler, be sure the new handler is registerd or
  // you include it in some other way.
  drupal_alter('linkit_plugins', $plugins);
  return $plugins;
}

/**
 * Fetch metadata for one linkit plugin by the given name.
 */
function linkit_get_plugin($plugin_name) {
  ctools_include('plugins');
  $plugin = ctools_get_plugins('linkit', 'linkit_plugins', $plugin_name);
  // If you alter the plugin handler, be sure the new handler is registerd or
  // you include it in some other way.
  drupal_alter('linkit_plugin', $plugin);
  return $plugin;
}

/**
 * Get the "best" Linkit profile based on the users roles to use on the
 * dashboard.
 */
function linkit_get_dashboard_profile() {
  global $user;
  $best_profile = &drupal_static(__FUNCTION__);

  if (!isset($best_profile)) {
    $best_profile = NULL;
    // Get the profiles.
    $profiles = linkit_profile_load_all();
    usort($profiles, '_linkit_sort_profiles_by_weight');

    foreach ($profiles as $profile) {
      // Dont work with disabled profiles.
      if (isset($profile->disabled) && $profile->disabled) {
        continue;
      }

      // Loop thru the associated roles, if we get a match, use that and break
      // out of this loop.
      foreach ($profile->role_rids as $rid => $value) {
        if (array_key_exists($rid, $user->roles)) {
          $best_profile = $profile;
          break 2;
        }
      }
    }
  }

  return $best_profile;
}

/**
 * Sort profiles by weight.
 */
function _linkit_sort_profiles_by_weight($a, $b) {
  return $a->weight >= $b->weight;
}

/**
 * Get all Linkit profiles and return there names.
 *
 * @return
 *   An array that can be used as an #options in a form.
 */
function _linkit_get_profile_names() {
  $profiles = linkit_profile_load_all();
  $profile_names= array();
  foreach ($profiles AS $profile) {
    $profile_names[$profile->name] = $profile->admin_title;
  }
  return $profile_names;
}

/**
 * Load a single Linkit profile.
 */
function linkit_profile_load($name) {
  $cache = &drupal_static('__FUNCTION__', array());
  if (!isset($cache[$name])) {
    ctools_include('export');
    $result = ctools_export_load_object('linkit_profiles', 'names', array($name));
    if (isset($result[$name])) {
      $cache[$name] = $result[$name];
    }
    else {
      return FALSE;
    }
  }
  return $cache[$name];
}

/**
 * Load all Linkit profiles.
 */
function linkit_profile_load_all() {
  ctools_include('export');
  $profiles = ctools_export_load_object('linkit_profiles');
  return $profiles;
}

/**
 * Save a single Linkit profile.
 */
function linkit_profile_save($profile) {
  $schema = ctools_export_get_schema('linkit_profiles');
  $export = $schema['export'];

  // Objects should have a serial primary key. If not, simply fail to write.
  if (empty($export['primary key'])) {
    return FALSE;
  }

  $key = $export['primary key'];
  if ($profile->export_type & EXPORT_IN_DATABASE) {
    // Existing record.
    $update = array($key);
  }
  else {
    // New record.
    $update = array();
    $profile->export_type = EXPORT_IN_DATABASE;
  }
  return drupal_write_record('linkit_profiles', $profile, $update);
}

/**
 * Implements hook_ctools_plugin_directory().
 */
function linkit_ctools_plugin_directory($module, $plugin) {
  if ($module == 'ctools' && !empty($plugin)) {
    return "plugins/" . $plugin;
  }
  if ($module == 'linkit' && !empty($plugin)) {
    return "plugins/" . $plugin;
  }
}

/**
 * Implements hook_ctools_plugin_TYPE() to inform the plugin system that Linkit
 * owns Linkit plugin types.
 */
function linkit_ctools_plugin_type() {
  $plugins['linkit_plugins'] = array(
    'child plugins' => TRUE,
    'classes' => array('handler'),
  );
  $plugins['linkit_insert'] = array(
    'classes' => array('handler'),
  );
  return $plugins;
}

/**
 * Get the plugin handler for a given plugin.
 */
function linkit_get_plugin_handler($plugin, $profile = NULL) {
  $object_cache = drupal_static(__FUNCTION__);
  $identifier = $plugin['name'];
  if (!isset($object_cache[$identifier])) {
    ctools_include('plugins');
    // Try load the default handler.
    $class = ctools_plugin_get_class($plugin, 'handler');
    if (class_exists($class)) {
      $object_cache[$identifier] = new $class($plugin, $profile);
    }
    else {
      $object_cache[$identifier] = new LinkitPluginBroken($plugin, $profile);

      // The default handler class does not seems to exists, lets try the
      // entity fallback handler if we have any.
      if (isset($plugin['entity fallback handler'])) {
        $fallback_class = ctools_plugin_get_class($plugin, 'entity fallback handler');
        if (class_exists($fallback_class)) {
          $object_cache[$identifier] = new $fallback_class($plugin, $profile);
        }
      }
    }
  }
  return $object_cache[$identifier];
}


/**
 * Extract tokens that can be used by the $type.
 */
function linkit_extract_tokens($type) {
  // token_info() has it own static cache, so we can call it as we like.
  $tokens = token_info();
  // If no tokens for the type exists, return an empty array.
  if (!isset($tokens['tokens'][$type])) {
    return array();
  }

  $available_tokens = array();
  foreach ($tokens['tokens'][$type] as $token_key => $token) {
    $available_tokens[] = '[' . $type . ':' . $token_key . ']';
  }

  return $available_tokens;
}

/**
 * Implements hook_entity_info_alter();
 *
 * Control which enteties that can be used by Linkit.
 * Other modules can easy implement this hook aswell and make their enteties
 * usable with Linkit or change directly in the the hook_entity_info().
 */
function linkit_entity_info_alter(&$entity_info) {
  // An array of entity names that is allowed to be used in Linkit.
  $allowed = array('node', 'user', 'taxonomy_term', 'file');

  foreach ($allowed as $entity_name) {
    if (isset($entity_info[$entity_name])) {
      $entity_info[$entity_name]['linkit'] = TRUE;
    }
  }
}

/**
 * Implements hook_linkit_plugin_entities_alter().
 *
 * The default behavior for entities is that they will use the default entity
 * plugin class, which will provide them with the basic methods they need.
 *
 * Tho there is some plugins that will extend those basic method with more
 * advanced once, therefor the handlers for those plugins will have to be
 * changed.
 *
 * @param array $plugins
 *   An array of all entity plugins processed within Linkit entity plugin.
 */
function linkit_linkit_plugin_entities_alter(&$plugins) {
  $alter_plugins = array(
    'entity:node',
    'entity:user',
    'entity:taxonomy_term',
    'entity:file',
  );

  $path = drupal_get_path('module', 'linkit') . '/plugins/linkit_plugins';

  foreach ($alter_plugins as $plugin) {
    if (isset($plugins[$plugin])) {
      $handler = array(
        'class' => 'LinkitPlugin' . drupal_ucfirst($plugins[$plugin]['entity_type']),
        'file' => 'linkit-plugin-' . $plugins[$plugin]['entity_type'] . '.class.php',
        'path' => $path,
      );
      $plugins[$plugin]['handler'] = $handler;
    }
  }
}