<?php
// $Id$

/**
 * @file
 * Panels integration for the Flag module.
 *
 * Exposes the flag-links as Panels "content types".
 */

/**
 * Implementation of hook_panels_content_types
 */
function flag_panels_content_types() {
  $items['flag_link'] = array(
    'title' => t('Flag link'),
    'single' => FALSE,
    'content_types'   => 'flag_panels_link_content_types',
    'title callback'  => 'flag_panels_link_title',
    'add callback'    => 'flag_panels_link_add',
    'edit callback'   => 'flag_panels_link_edit',
    'render callback' => 'flag_panels_link_render',
  );
  return $items;
}

/**
 * Callback. Returns all flag links available, each as a "content type".
 */
function flag_panels_link_content_types() {
  $items = array();
  $flags = flag_get_flags();
  foreach ($flags as $flag) {
    $info = array(
      'title' => t('Flag link (@flag-title)', array('@flag-title' => $flag->get_title())),
      // For the time being, let's borrow Views' icon.
      'icon' => 'icon_views_page.png',
      'path' => panels_get_path('content_types/views'),
    );
    switch ($flag->content_type) {
      case 'node':
        $info += array(
          'description' => t('A link to flag, or unflag, a node.'),
          'required context' => new panels_required_context(t('Node'), 'node'),
          'category' => t('Node context'),
        );
        break;
      case 'user':
        $info += array(
          'description' => t('A link to flag, or unflag, a user.'),
          'required context' => new panels_required_context(t('User'), 'user'),
          'category' => t('User context'),
        );
        break;
      case 'term':
        $info += array(
          'description' => t('A link to flag, or unflag, a taxonomy term.'),
          'required context' => new panels_required_context(t('Term'), 'term'),
          'category' => t('Term context'),
        );
        break;
      default:
        $info = array();
    }
    if ($info) {
      $items['flag_link_' . $flag->name] = $info;
    }
  }
  return $items;
}

/**
 * Callback. Returns an administrative title for the link.
 */
function flag_panels_link_title($conf, $context) {
  $flag_name = $conf['flag_name'];
  $flag = flag_get_flag($flag_name);
  if ($flag) {
    return t('"@s" flag/unflag link', array('@s' => $flag->get_title()));
  }
  else {
    return t('Error: Flag "@s" is not defined.', array('@s' => $flag_name));
  }
}

/**
 * Callback. Returns the form for a new link.
 */
function flag_panels_link_add($id, $parents, $conf = array()) {
  $conf['flag_name'] = substr($id, strlen('flag_link_'));
  return flag_panels_link_edit($id, $parents, $conf);
}

/**
 * Callback. Returns an edit form for a link.
 */
function flag_panels_link_edit($id, $parents, $conf) {
  $form['flag_name'] = array(
    '#type' => 'value',
    '#value' => $conf['flag_name'],
  );
  $form['flag_reminder_message'] = array(
    '#type' => 'markup',
    '#value' => '<p><em>' . t("A reminder: the flag (or unflag) link won't show unless in the <a href='@flag-settings-url'>flag's settings page</a> you have enabled this flag for this object. For example, if the flag is used to flag nodes, then if the object being displayed is a node of type 'story' but you've enabled the flag for nodes of type 'page' only, the link won't show.", array('@flag-settings-url' => url('admin/build/flags/edit/' . $conf['flag_name']))) . '</em></p>',
  );
  return $form;
}

/**
 * Callback. Renders a flag link
 */
function flag_panels_link_render($conf, $panel_args, $context) {
  if (!empty($context) && empty($context->data)) {
    return;
  }
  $flag_name = $conf['flag_name'];
  $flag = flag_get_flag($flag_name);
  if ($flag) {
    $link->title = $flag->get_title();
    $link->content = flag_create_link($flag_name, $flag->get_content_id($context->data));
  }
  else {
    $link->title = t('Flag "@flag-name" is not defined.', array('@flag-name' => $flag_name));
    $link->content = $link->title;
  }
  return $link;
}