<?php

/**
 * @file
 * Main file for panels breadcrumbs module.
 */

/**
 * Implements hook_page_manager_variant_operations_alter().
 *
 * Shameful rip off from panels_everywhere module.
 *
 * @see panels_everywhere_page_manager_variant_operations_alter()
 * @see http://groups.drupal.org/node/110719#comment-356094
 */
function panels_breadcrumbs_page_manager_variant_operations_alter(&$operations, $handler) {

  // Use this obnoxious construct to safely insert our item.
  reset($operations['children']);
  $children_operations = array();
  while (list($key, $value) = each($operations['children'])) {
    $children_operations[$key] = $value;
    if ($key == 'context') {
      $children_operations['breadcrumb'] = array(
        'title' => t('Breadcrumb'),
        'description' => t('Edit variant level breadcrumbs. This will modify the global breadcrumb variable for this page, and all non-overriden breadcrumb panes present in this page will use this breadcrumb configuration.'),
        'form' => 'panels_breadcrumbs_variant_breadcrumb_form',
      );
    }
  }
  $operations['children'] = $children_operations;
}

/**
 * Panels breadcrumbs configuration form.
 */
function panels_breadcrumbs_variant_breadcrumb_form($form, &$form_state) {
  ctools_include('context-task-handler');

  $handler = $form_state['handler'];
  $contexts = ctools_context_handler_get_all_contexts($form_state['task'], $form_state['subtask'], $handler);

  $form += panels_breadcrumbs_partial_configuration_form($handler->conf, $contexts);

  return $form;
}

/**
 * Submission callback handler for panels breadcrumbs configuration form.
 */
function panels_breadcrumbs_variant_breadcrumb_form_submit($form, &$form_state) {
  $form_state['handler']->conf['panels_breadcrumbs_state'] = $form_state['values']['panels_breadcrumbs_state'];
  $form_state['handler']->conf['panels_breadcrumbs_titles'] = $form_state['values']['panels_breadcrumbs_titles'];
  $form_state['handler']->conf['panels_breadcrumbs_paths'] = $form_state['values']['panels_breadcrumbs_paths'];
  $form_state['handler']->conf['panels_breadcrumbs_home'] = $form_state['values']['panels_breadcrumbs_home'];
}

/**
 * Implements hook_ctools_render_alter().
 *
 * When a Page Manager page is rendered, build the breadcrumb if it exists.
 */
function panels_breadcrumbs_ctools_render_alter($info, $page, $context) {
  $handler = $context['handler'];
  $contexts = ctools_context_handler_get_handler_contexts($context['contexts'], $handler);

  if (isset($handler->conf['panels_breadcrumbs_state']) && $handler->conf['panels_breadcrumbs_state']) {
    panels_breadcrumbs_build_breadcrumb($handler->conf, $contexts, TRUE);
  }
}

/**
 * Returns a partially formed panels breadcrumbs configuration form.
 *
 * @param $conf
 * @param $contexts
 * @return
 *  An array containing a partial panels breadcrumbs configuration form.
 */
function panels_breadcrumbs_partial_configuration_form($conf, $contexts) {
  if (empty($conf['panels_breadcrumbs_state'])) {
    $conf['panels_breadcrumbs_state'] = '0';
  }

  if (empty($conf['panels_breadcrumbs_titles'])) {
    $conf['panels_breadcrumbs_titles'] = '';
  }

  if (empty($conf['panels_breadcrumbs_paths'])) {
    $conf['panels_breadcrumbs_paths'] = '';
  }

  $form['settings']['panels_breadcrumbs_state'] = array(
    '#type' => 'checkbox',
    '#title' => t('Enable custom breadcrumb configuration.'),
    '#default_value' => $conf['panels_breadcrumbs_state'],
  );
  $form['settings']['panels_breadcrumbs_titles'] = array(
    '#type' => 'textarea',
    '#title' => t('Breadcrumb titles'),
    '#description' => t('Enter one title per line.'),
    '#default_value' => $conf['panels_breadcrumbs_titles'],
  );
  $form['settings']['panels_breadcrumbs_paths'] = array(
    '#type' => 'textarea',
    '#title' => t('Breadcrumb paths'),
    '#description' => t('Enter one path per line. You can use @front to link
      to the front page, or @none for no link.', array('@front' => '<front>', '@none' => '<none>')),
    '#default_value' => $conf['panels_breadcrumbs_paths'],
  );
  $form['settings']['panels_breadcrumbs_home'] = array(
    '#type' => 'checkbox',
    '#title' => t('Prepend Home Link to the Breadcrumb'),
    '#default_value' => isset($conf['panels_breadcrumbs_home']) ? $conf['panels_breadcrumbs_home'] : TRUE,
  );

  $rows = array();
  foreach ($contexts as $context) {
    foreach (ctools_context_get_converters('%' . check_plain($context->keyword) . ':', $context) as $keyword => $title) {
      $rows[] = array(
        check_plain($keyword),
        t('@identifier: @title', array('@title' => $title, '@identifier' => $context->identifier)),
      );
    }
  }

  $header = array(t('Keyword'), t('Value'));
  $form['contexts'] = array(
    '#type' => 'fieldset',
    '#title' => t('Substitutions'),
    '#collapsible' => TRUE,
    '#collapsed' => TRUE,
    '#value' => theme('table', array('header' => $header, 'rows' => $rows)),
  );

  return $form;
}

/**
 * Builds a custom breadcrumb from the provided contexts and configuration.
 *
 * @param $conf
 *   An array containing:
 *    - panels_breadcrumbs_title: A string containing a series of titles
 *      separated by a line break.
 *    - panels_breadcrumbs_paths: A string containing a series of paths
 *      separated by a line break.
 *    - panels_breadcrumbs_home: A boolean that enables the display of an 'Home'
 *      root link on the breadcrumb.
 * @param $contexts
 *   A ctools contexts array
 * @param $override
 *   A boolean that makes this breadcrumb configuration override the global settings.
 * @return array
 *   A properly structured array of links as expected by theme_breadcrumb(), or
 *   FALSE if the breadcrumb could not be built with the given configuration.
 */
function panels_breadcrumbs_build_breadcrumb($conf, $contexts, $override = FALSE) {
  $breadcrumbs = array();

  // If no titles or paths are defined, bail out.
  if (!isset($conf['panels_breadcrumbs_titles']) || !isset($conf['panels_breadcrumbs_paths'])) {
    return;
  }

  // Look for placeholder tokens in paths and convert them for this display
  $titles = $conf['panels_breadcrumbs_titles'];
  $paths = ctools_context_keyword_substitute($conf['panels_breadcrumbs_paths'], array(), $contexts);

  // Break titles and paths into arrays and remove empty keys
  $titles = array_filter(array_map('trim', explode(PHP_EOL, $titles)), 'strlen');
  $paths = array_filter(array_map('trim', explode(PHP_EOL, $paths)), 'strlen');

  $default_breadcrumb_info = array(
    'title' => '',
    'href' => '',
    'localized_options' => array(),
  );

  $breadcrumbs_info = array();

  // Set the first crumb to home
  if (!isset($conf['panels_breadcrumbs_home']) || $conf['panels_breadcrumbs_home'] == TRUE) {
    $breadcrumbs_info[] = array('title' => t('Home'), 'href' => '<front>') + $default_breadcrumb_info;
  }

  // Iterate through all crumbs and add them to the breadcrumb
  foreach ($titles as $key => $title) {

    // Translate the title and convert existing placeholder tokens afterwards.
    $translated_title = t($title);
    $translated_title = ctools_context_keyword_substitute($translated_title, array(), $contexts);

    if (empty($translated_title)) {
      continue;
    }

    $translated_title = html_entity_decode(trim($translated_title), ENT_QUOTES, 'UTF-8');
    $path = empty($paths[$key]) ? '<none>' : trim($paths[$key]);
    $breadcrumbs_info[] = array('title' => $translated_title, 'href' => $path) + $default_breadcrumb_info;
  }

  // Allow other modules to intercept and operate changes in the breadcrumb
  $breadcrumb_info_end = end($breadcrumbs_info);
  drupal_alter('menu_breadcrumb', $breadcrumbs_info, $breadcrumb_info_end);

  // Finally, render the breadcrumb
  foreach ($breadcrumbs_info as $crumb) {
    if (isset($crumb['href']) && $crumb['href'] == '<none>') {
      $crumb['localized_options'] += array('attributes' => array(), 'html' => TRUE);
      $breadcrumbs[] = '<span ' . drupal_attributes($crumb['localized_options']['attributes']) . '>' . ($crumb['localized_options']['html'] ? $crumb['title'] : check_plain($crumb['title'])) . '</span>';
    }
    else {
      $breadcrumbs[] = l($crumb['title'], $crumb['href'], $crumb['localized_options']);
    }
  }

  // Optionally override the global breadcrumb configuration
  if ($override) {
    drupal_set_breadcrumb($breadcrumbs);
  }

  return $breadcrumbs;
}

// CTools breadcrumb content-type plugin override
// -----------------------------------------------------------------------------

/**
 * Implements hook_ctools_plugin_pre_alter().
 */
function panels_breadcrumbs_ctools_plugin_pre_alter(&$plugin, $info) {
  // Modifies the core ctools breadcrumb content-type implementation
  if ($plugin['name'] == 'page_breadcrumb') {
    $plugin['all contexts'] = TRUE;
    $plugin['edit form'] = 'panels_breadcrumbs_page_breadcrumb_content_type_edit_form';
    $plugin['render callback'] = 'panels_breadcrumbs_page_breadcrumb_content_type_render';
    $plugin['admin title'] = 'panels_breadcrumbs_page_breadcrumb_content_type_admin_title';
    $plugin['admin info'] = 'panels_breadcrumbs_page_breadcrumb_content_type_admin_info';
    $plugin['defaults'] = array(
      'panels_breadcrumbs_admin_title' => '',
      'panels_breadcrumbs_state' => 0,
      'panels_breadcrumbs_titles' => '',
      'panels_breadcrumbs_paths' => '',
      'panels_breadcrumbs_home' => 0,
    );
  }
}

/**
 * Render callback override of 'page_breadcrumb' ctools content-type.
 */
function panels_breadcrumbs_page_breadcrumb_content_type_render($subtype, $conf, $panel_args, $contexts) {
  $panelizer_conf = panels_breadcrumbs_get_panelizer_breadcrumb_conf();
  $current_page = page_manager_get_current_page();

  // Find which breadcrumb configuration to use.
  if (isset($conf['panels_breadcrumbs_state']) && $conf['panels_breadcrumbs_state']) {
    $correct_conf = $conf;
  }
  elseif (!empty($panelizer_conf)) {
    $correct_conf = $panelizer_conf;
  }
  elseif (!empty($current_page)) {
    $correct_conf = $current_page['handler']->conf;
  }

  // If no breadcrumb configuration was found, fallback to Drupal's default.
  if (isset($correct_conf) && !empty($correct_conf['panels_breadcrumbs_state'])) {
    $breadcrumb = panels_breadcrumbs_build_breadcrumb($correct_conf, $contexts);
  }
  else {
    $breadcrumb = drupal_get_breadcrumb();
  }

  $block = new stdClass();
  $block->content = theme('breadcrumb', array('breadcrumb' => $breadcrumb));

  return $block;
}

/**
 * Configuration callback override of 'page_breadcrumb' ctools content-type.
 */
function panels_breadcrumbs_page_breadcrumb_content_type_edit_form($form, &$form_state) {
  $form += panels_breadcrumbs_partial_configuration_form($form_state['conf'], $form_state['contexts']);

  $form['settings']['panels_breadcrumbs_state']['#title'] = t('Use a custom breadcrumb configuration for this content pane.');

  $form['settings']['panels_breadcrumbs_admin_title'] = array(
    '#type' => 'textfield',
    '#default_value' => isset($form_state['conf']['panels_breadcrumbs_admin_title']) ? $form_state['conf']['panels_breadcrumbs_admin_title'] : '',
    '#title' => t('Administrative title'),
    '#description' => t('This title will be used administratively to identify this pane. If blank, the regular title will be used.'),
    '#weight' => -5,
  );

  return $form;
}

/**
 * Submission callback for the 'page_breadcrumb' ctools content-type edit form.
 */
function panels_breadcrumbs_page_breadcrumb_content_type_edit_form_submit($form, &$form_state) {
  // Copy everything from the defaults.
  foreach (array_keys($form_state['plugin']['defaults']) as $key) {
    $form_state['conf'][$key] = $form_state['values'][$key];
  }
}

/**
 * Admin title callback for the 'page_breadcrumb'ctools content-type.
 */
function panels_breadcrumbs_page_breadcrumb_content_type_admin_title($subtype, $conf) {
  if (!empty($conf['panels_breadcrumbs_admin_title'])) {
    return t('Breadcrumb - <em>@admin_title</em>', array('@admin_title' => strip_tags($conf['panels_breadcrumbs_admin_title'])));
  }

  return t('Breadcrumb');
}

/**
 * Admin info callback for the 'page_breadcrumb'ctools content-type.
 */
function panels_breadcrumbs_page_breadcrumb_content_type_admin_info($subtype, $conf) {
  $title = t('Default');

  if (!empty($conf['panels_breadcrumbs_state']) && $conf['panels_breadcrumbs_state']) {
    $title = t('Overrides variant level configuration.');
  }

  $block = new stdClass();
  $block->title = $title;
  $block->content = '';
  return $block;
}

// Panelizer integration
// -----------------------------------------------------------------------------

/**
 * Implements hook_panelizer_operations_alter().
 */
function panels_breadcrumbs_panelizer_operations_alter(&$operations) {
  $operations['breadcrumbs'] = array(
    'menu title' => 'Breadcrumbs',
    'link title' => t('breadcrumbs'),
    'entity callback' => 'panels_breadcrumbs_panelizer_breadcrumbs_entity_page',
    'admin callback' => 'panels_breadcrumbs_panelizer_breadcrumbs_admin_page',
  );
}

/**
 * Panelizer breadcrumbs operation entity page callback.
 */
function panels_breadcrumbs_panelizer_breadcrumbs_entity_page($handler, $js, $input, $entity, $view_mode) {
  $panelizer = $entity->panelizer[$view_mode];
  if (empty($panelizer)) {
    return MENU_NOT_FOUND;
  }

  list($entity_id, $revision_id, $bundle) = entity_extract_ids($handler->entity_type, $entity);

  $form_state = array(
    'entity' => $entity,
    'revision info' => $handler->entity_allows_revisions($entity),
    'display cache' => panels_edit_cache_get(implode(':', array('panelizer', $handler->entity_type, $entity_id, $view_mode))),
    'no_redirect' => TRUE,
    'panelizer' => $panelizer,
  );

  ctools_include('common', 'panelizer');
  $output = drupal_build_form('panels_breadcrumbs_panelizer_breadcrumbs_form', $form_state);

  if (!empty($form_state['executed'])) {
    if ($form_state['clicked_button']['#name'] == 'save') {
      drupal_set_message(t('The settings have been updated.'));

      $entity->panelizer[$view_mode]->extra['panels_breadcrumbs_state'] = $form_state['values']['panels_breadcrumbs_state'];
      $entity->panelizer[$view_mode]->extra['panels_breadcrumbs_titles'] = $form_state['values']['panels_breadcrumbs_titles'];
      $entity->panelizer[$view_mode]->extra['panels_breadcrumbs_paths'] = $form_state['values']['panels_breadcrumbs_paths'];
      $entity->panelizer[$view_mode]->extra['panels_breadcrumbs_home'] = $form_state['values']['panels_breadcrumbs_home'];

      $handler->entity_save($entity);
    }
    else {
      drupal_set_message(t('Changes have been discarded.'));
    }

    drupal_goto($_GET['q']);
  }

  $output = $handler->wrap_entity_panelizer_pages($entity, $view_mode, $output);

  ctools_set_no_blocks(FALSE);
  drupal_set_page_content($output);
  $page = element_info('page');
  return $page;
}

/**
 * Panelizer breadcrumbs operation admin page callback.
 */
function panels_breadcrumbs_panelizer_breadcrumbs_admin_page($handler, $bundle, $name, $view_mode) {
  if (is_string($handler)) {
    $handler = panelizer_entity_plugin_get_handler($handler);
  }

  if ($view_mode) {
    $bundle .= '.' . $view_mode;
  }

  $panelizer = $handler->get_default_panelizer_object($bundle, $name);
  if (empty($panelizer)) {
    return MENU_NOT_FOUND;
  }

  $cache_key = 'panelizer:default:' . $handler->entity_type . ':' . $bundle . ':' . $name;

  $form_state = array(
    'display cache' => panels_edit_cache_get($cache_key),
    'no_redirect' => TRUE,
    'panelizer' => $panelizer,
  );

  ctools_include('common', 'panelizer');
  $output = drupal_build_form('panels_breadcrumbs_panelizer_breadcrumbs_form', $form_state);

  if (!empty($form_state['executed'])) {
    if ($form_state['clicked_button']['#name'] == 'save') {
      drupal_set_message(t('The settings have been updated.'));

      $panelizer->extra['panels_breadcrumbs_state'] = $form_state['values']['panels_breadcrumbs_state'];
      $panelizer->extra['panels_breadcrumbs_titles'] = $form_state['values']['panels_breadcrumbs_titles'];
      $panelizer->extra['panels_breadcrumbs_paths'] = $form_state['values']['panels_breadcrumbs_paths'];
      $panelizer->extra['panels_breadcrumbs_home'] = $form_state['values']['panels_breadcrumbs_home'];

      ctools_export_crud_save('panelizer_defaults', $panelizer);
    }
    else {
      drupal_set_message(t('Changes have been discarded.'));
    }

    drupal_goto($_GET['q']);
  }

  ctools_set_no_blocks(FALSE);

  if ($view_mode) {
    $output = $handler->wrap_default_panelizer_pages($bundle, $output);
  }

  drupal_set_page_content($output);
  $page = element_info('page');

  return $page;
}

/**
 * Panelizer breadcrumb configuration form.
 */
function panels_breadcrumbs_panelizer_breadcrumbs_form($form, $form_state) {
  ctools_include('context');

  $panelizer = $form_state['panelizer'];
  $contexts = ctools_context_load_contexts($panelizer);

  $form = panels_breadcrumbs_partial_configuration_form($form_state['panelizer']->extra, $contexts);

  $form['actions'] = array(
    '#type' => 'actions',
  );

  $form['actions']['submit'] = array(
    '#type' => 'submit',
    '#value' => t('Save'),
    '#name' => 'save',
  );

  $form['actions']['cancel'] = array(
    '#type' => 'submit',
    '#value' => t('Cancel'),
    '#name' => 'cancel',
  );

  return $form;
}

/**
 * Implements hook_panelizer_pre_render_alter().
 *
 * Set the breadcrumb for the panelized entity.
 */
function panels_breadcrumbs_panelizer_pre_render_alter(&$panelizer, &$display, $entity) {
  if (isset($panelizer->entity_type)) {
    $entity_type = $panelizer->entity_type;
  }
  elseif (isset($panelizer->panelizer_type)) {
    $entity_type = $panelizer->panelizer_type;
  }
  else {
    return;
  }

  $panelizer_entity_plugin = panelizer_entity_plugin_get_handler($entity_type);
  $contexts = $panelizer_entity_plugin->get_contexts($panelizer);

  if (!empty($panelizer->extra['panels_breadcrumbs_state']) && $panelizer->extra['panels_breadcrumbs_state']) {
    panels_breadcrumbs_build_breadcrumb($panelizer->extra, $contexts, TRUE);

    // Store the panelizer breadcrumb configuration
    panels_breadcrumbs_get_panelizer_breadcrumb_conf($panelizer->extra);
  }
}

/**
 * Returns the breadcrumb configuration for the panelized entity.
 */
function panels_breadcrumbs_get_panelizer_breadcrumb_conf($conf = FALSE) {
  $panelizer_conf = &drupal_static(__FUNCTION__);

  if ($conf) {
    $panelizer_conf = $conf;
  }

  return $panelizer_conf;
}