<?php

/**
 * @file
 * panels_mini.module
 *
 * This module provides mini panels which are basically panels that can be
 * used within blocks or other panels.
 */

/**
 * Implementation of hook_permission().
 */
function panels_mini_permission() {
  return array(
    'create mini panels' => array(
      'title' => t('Create mini panels'),
      'description' => t('Create new mini panels'),
    ),
    'administer mini panels' => array(
      'title' => t('Administer mini panels'),
      'description' => t('Edit and delete mini panels'),
    ),
  );
}

/**
 * Implementation of hook_menu().
 */
function panels_mini_menu() {
  // Safety: go away if CTools is not at an appropriate version.
  if (!defined('PANELS_REQUIRED_CTOOLS_API') || !module_invoke('ctools', 'api_version', PANELS_REQUIRED_CTOOLS_API)) {
    return array();
  }

  $items['admin/structure/mini-panels/settings'] = array(
    'title' => 'Settings',
    'page callback' => 'panels_mini_settings',
    'access arguments' => array('create mini panels'),
    'type' => MENU_LOCAL_TASK,
  );

  // Also provide settings on the main panel UI.
  $items['admin/structure/panels/settings/panels-mini'] = array(
    'title' => 'Mini panels',
    'page callback' => 'panels_mini_settings',
    'access arguments' => array('create mini panels'),
    'type' => MENU_LOCAL_TASK,
  );

  return $items;
}

/**
 * Settings for mini panels.
 */
function panels_mini_settings() {
  ctools_include('common', 'panels');
  return drupal_get_form('panels_common_settings', 'panels_mini');
}

// ---------------------------------------------------------------------------
// Allow the rest of the system access to mini panels.

/**
 * Implementation of hook_block_info().
 */
function panels_mini_block_info() {
  // Safety: go away if CTools is not at an appropriate version.
  if (!defined('PANELS_REQUIRED_CTOOLS_API') || !module_invoke('ctools', 'api_version', PANELS_REQUIRED_CTOOLS_API)) {
    return array();
  }

  $blocks = array();

  $minis = panels_mini_load_all();
  foreach ($minis as $panel_mini) {
    if (empty($panel_mini->disabled) && (module_exists('page_manager') || empty($panel_mini->requiredcontexts))) {
      $blocks[$panel_mini->name] = array(
        'info' => t('Mini panel: "@title"', array('@title' => $panel_mini->admin_title)),
        'cache' => DRUPAL_NO_CACHE,
      );
    }
  }

  return $blocks;
}

/**
 * Implementation of hook_block_view().
 *
 * @see panels_mini_panels_mini_content_type_render()
 */
function panels_mini_block_view($delta = 0) {
  // Static recursion protection.
  static $viewing = array();
  if (!empty($viewing[$delta])) {
    return;
  }
  $viewing[$delta] = TRUE;

  $panel_mini = panels_mini_load($delta);
  if (empty($panel_mini)) {
    // Bail out early if the specified mini panel doesn't exist.
    return;
  }

  ctools_include('context');

  $contexts = array();
  if (module_exists('page_manager') && $current_page = page_manager_get_current_page()) {
    if (!empty($current_page['contexts'])) {
      $contexts = ctools_context_match_required_contexts($panel_mini->requiredcontexts, $current_page['contexts']);
    }
  }
  drupal_alter('panels_mini_block_contexts', $contexts, $panel_mini);

  $panel_mini->context = $panel_mini->display->context = ctools_context_load_contexts($panel_mini, FALSE, $contexts);
  $panel_mini->display->css_id = panels_mini_get_id($panel_mini->name);
  $panel_mini->display->owner = $panel_mini;

  $block = array();

  $block['content'] = panels_render_display($panel_mini->display);
  $block['subject'] = $panel_mini->display->get_title();

  unset($viewing[$delta]);
  return $block;
}

/**
 * Implementation of hook_block_configure().
 */
function panels_mini_block_configure($delta = 0) {
  return array(
    'admin_shortcut' => array(
      '#markup' => l(t('Manage this mini-panel'), 'admin/structure/mini-panels/list/' . $delta . '/edit'),
    ),
  );
}

/**
 * Implements hook_block_list_alter().
 *
 * Remove the block if the required contexts are not available.
 */
function panels_mini_block_list_alter(&$blocks) {
  $keys_to_cache = array();
  $has_cache_hit = FALSE;
  foreach ($blocks as $key => $block) {
    if ($block->module != 'panels_mini') {
      // Ignore anything that is not a mini panel.
      continue;
    }

    $result = cache_get('panels_mini_block_list_alter:' . $key, 'cache_panels');
    if (empty($result->data)) {
      // If not a cache hit, queue it for caching.
      $keys_to_cache[] = $key;
    }
    else {
      // If a cache hit, return the cached result and indicate we had a hit.
      $blocks[$key] = $result->data;
      $has_cache_hit = TRUE;
    }
  }

  // If we don't need to cache anything, exit out of the function.
  if (empty($keys_to_cache)) {
    return;
  }
  $current_page = FALSE;
  if (module_exists('page_manager')) {
    $current_page = page_manager_get_current_page();
  }

  // If we didn't have any cache hits, load all at once to save time.
  if (!$has_cache_hit) {
    panels_mini_load_all();
  }

  // Iterate through all non-cached keys.
  foreach ($keys_to_cache as $key) {
    $block = $blocks[$key];
    if ($block->module != 'panels_mini') {
      // This block was added by a contrib module, leave it in the list.
      continue;
    }

    $panel_mini = panels_mini_load($block->delta);
    if (empty($panel_mini)) {
      // Bail out early if the specified mini panel doesn't exist.
      unset($blocks[$key]);
      continue;
    }

    if (!empty($panel_mini->requiredcontexts)) {
      if (!$current_page || empty($current_page['contexts'])) {
        unset($blocks[$key]);
        continue;
      }
      else {
        $required = array();
        foreach ($panel_mini->requiredcontexts as $context) {
          $info = ctools_get_context($context['name']);
          $required[] = new ctools_context_required($context['identifier'], $info['context name']);
        }
        if (!ctools_context_match_requirements($current_page['contexts'], $required)) {
          unset($blocks[$key]);
          continue;
        }
      }
    }

    // Cache our results.
    cache_set('panels_mini_block_list_alter:' . $key, $blocks[$key], 'cache_panels', CACHE_TEMPORARY);
  }
}

/**
 * Implements hook_get_pane_links_alter().
 */
function panels_mini_get_pane_links_alter(&$links, $pane, $content_type) {
  if ($pane->type == 'panels_mini') {
    $links['top']['edit_panels_mini'] = array(
      'title' => t('Edit mini panel'),
      'href' => url('admin/structure/mini-panels/list/' . $pane->subtype . '/edit/content', array('absolute' => TRUE)),
      'attributes' => array('target' => array('_blank')),
    );
  }
}

/**
 * Implements hook_contextual_links_view_alter().
 */
function panels_mini_contextual_links_view_alter(&$element, $items) {

  // Add contextual links to all mini panel blocks with bid property.
  if (isset($element['#element']['#block']) && isset($element['#element']['#block']->bid) && strpos((string) $element['#element']['#block']->bid, 'panels_mini') === 0) {

    $admin_pages = array(
      t('Configure mini panel settings') => 'basic',
      t('Configure mini panel context') => 'context',
      t('Configure mini panel layout') => 'layout',
      t('Configure mini panel content') => 'content',
    );

    foreach ($admin_pages as $title => $tail) {
      $element['#links']['mini-panels-' . $tail] = array(
        'title' => $title,
        'href' => 'admin/structure/mini-panels/list/' . $element['#element']['#block']->delta . '/edit/' . $tail,
        'query' => drupal_get_destination(),
      );
    }
  }
}

/**
 * Statically store all used IDs to ensure all mini panels get a unique id.
 */
function panels_mini_get_id($name) {
  $id_cache = &drupal_static(__FUNCTION__, array());

  $id = 'mini-panel-' . $name;
  if (!empty($id_cache[$name])) {
    $id .= "-" . $id_cache[$name]++;
  }
  else {
    $id_cache[$name] = 1;
  }

  return $id;
}

// ---------------------------------------------------------------------------
// Database functions.

/**
 * Create a new page with defaults appropriately set from schema.
 */
function panels_mini_new($set_defaults = TRUE) {
  ctools_include('export');
  return ctools_export_new_object('panels_mini', $set_defaults);
}

/**
 * Load a single mini panel.
 */
function panels_mini_load($name) {
  $cache = &drupal_static('panels_mini_load_all', array());

  // We use array_key_exists because failed loads will be NULL and
  // isset() will try to load it again.
  if (!array_key_exists($name, $cache)) {
    $cid = 'panels_mini_load:' . $name;
    $result = cache_get($cid, 'cache_panels');
    if (!empty($result->data)) {
      $cache[$name] = $result->data;
    }
    else {
      ctools_include('export');
      $result = ctools_export_load_object('panels_mini', 'names', array($name));
      if (isset($result[$name])) {
        if (empty($result[$name]->display)) {
          $result[$name]->display = panels_load_display($result[$name]->did);
          if (!empty($result[$name]->title) && empty($result[$name]->display->title)) {
            $result[$name]->display->title = $result[$name]->title;
          }
        }
        $cache[$name] = $result[$name];
        if (!empty($result[$name]->title) && empty($result[$name]->admin_title)) {
          $cache[$name]->admin_title = $result[$name]->title;
        }
        cache_set($cid, $cache[$name], 'cache_panels', CACHE_TEMPORARY);
      }
      else {
        $cache[$name] = NULL;
      }
    }
  }

  if (isset($cache[$name])) {
    return $cache[$name];
  }
}

/**
 * Load all mini panels.
 */
function panels_mini_load_all($reset = FALSE) {
  $cache = &drupal_static('panels_mini_load_all', array());
  static $all_loaded = FALSE;

  // We check our own private static because individual minis could have
  // been loaded prior to load all and we need to know that.
  if (!$all_loaded || $reset) {
    $all_loaded = TRUE;
    if ($reset) {
      $cache = array();
    }
    else {
      $panel_names = db_select('panels_mini', 'pm')
        ->fields('pm', array('name'))
        ->execute();
      $cids = array();
      foreach ($panel_names as $name) {
        $cids[] = 'panels_mini_load:' . $name->name;
      }
      $output = cache_get_multiple($cids, 'cache_panels');
      foreach ($output as $mini) {
        if (!empty($mini->data)) {
          $mini = $mini->data;
          $cache[$mini->name] = $mini;
        }
      }
    }

    ctools_include('export');
    $minis = ctools_export_load_object('panels_mini');
    $dids = array();
    foreach ($minis as $mini) {
      if (empty($cache[$mini->name])) {
        if (!empty($mini->did)) {
          $dids[$mini->did] = $mini->name;
        }
        else {
          // Translate old style titles into new titles.
          if (!empty($mini->title) && empty($mini->display->title)) {
            $mini->display->title = $mini->title;
          }
        }
        // Translate old style titles into new titles.
        if (isset($mini->title) && empty($mini->admin_title)) {
          $mini->admin_title = $mini->title;
        }
        $cache[$mini->name] = $mini;
      }
    }

    $displays = panels_load_displays(array_keys($dids));
    foreach ($displays as $did => $display) {
      if (!empty($cache[$dids[$did]]->title) && empty($display->title)) {
        $display->title = $cache[$dids[$did]]->title;
      }
      $cache[$dids[$did]]->display = $display;
    }
  }

  // Strip out NULL entries that may have been added by panels_mini_load().
  return array_filter($cache);
}

/**
 * Write a mini panel to the database.
 */
function panels_mini_save(&$mini) {
  if (!empty($mini->display)) {
    $mini->display->storage_id = $mini->name;
    $display = panels_save_display($mini->display);
    $mini->did = $display->did;
  }

  // Clear the panels_mini_load cache.
  cache_clear_all('panels_mini_load:', 'cache_panels', TRUE);
  cache_clear_all('panels_mini_block_list_alter:', 'cache_panels', TRUE);

  $update = (isset($mini->pid) && $mini->pid != 'new') ? array('pid') : array();
  drupal_write_record('panels_mini', $mini, $update);

  return $mini;
}

/**
 * Remove a mini panel.
 */
function panels_mini_delete($mini) {
  db_delete('panels_mini')
    ->condition('name', $mini->name)
    ->execute();

  if (db_table_exists('block') && $mini->type != t('Overridden')) {
    // Also remove from block table as long as there isn't a default that may appear.
    db_delete('block')
      ->condition('delta', $mini->name)
      ->condition('module', 'panels_mini')
      ->execute();
  }
  return panels_delete_display($mini->did);
}

/**
 * Export a mini panel.
 */
function panels_mini_export($mini, $indent = '') {
  ctools_include('export');
  $output = ctools_export_object('panels_mini', $mini, $indent);
  // Export the primary display.
  $display = !empty($mini->display) ? $mini->display : panels_load_display($mini->did);
  $output .= panels_export_display($display, $indent);
  $output .= $indent . '$mini->display = $display' . ";\n";
  return $output;
}

/**
 * Remove the block version of mini panels from being available content types.
 */
function panels_mini_ctools_block_info($module, $delta, &$info) {
  $info = NULL;
}

/**
 * Implementation of hook_ctools_plugin_directory() to let the system know
 * we implement task and task_handler plugins.
 */
function panels_mini_ctools_plugin_directory($module, $plugin) {
  if ($module == 'ctools' && ($plugin == 'content_types' || $plugin == 'export_ui')) {
    return 'plugins/' . $plugin;
  }
  if ($module == 'panels' && $plugin == 'panels_storage') {
    return 'plugins/' . $plugin;
  }
}

/**
 * Implements hook_default_panels_mini_alter().
 *
 * If a default Panels display has no storage type, set it.
 */
function panels_default_panels_mini_alter(&$mini_panels) {
  foreach ($mini_panels as &$mini_panel) {
    $display =& $mini_panel->display;
    if (empty($display->storage_type)) {
      $display->storage_type = 'panels_mini';
      $display->storage_id = $mini_panel->name;
    }
  }
}

/**
 * Get the display cache for the panels_mini plugin.
 */
function _panels_mini_panels_cache_get($key) {
  ctools_include('export-ui');
  $plugin = ctools_get_export_ui('panels_mini');
  $handler = ctools_export_ui_get_handler($plugin);
  if (!$handler) {
    return;
  }

  $item = $handler->edit_cache_get($key);
  if (!$item) {
    $item = ctools_export_crud_load($handler->plugin['schema'], $key);
  }

  return array($handler, $item);
}

/**
 * Get display edit cache for the panels mini export UI.
 *
 * The key is the second half of the key in this form:
 * panels_mini:TASK_NAME:HANDLER_NAME;
 */
function panels_mini_panels_cache_get($key) {
  ctools_include('common', 'panels');
  list($handler, $item) = _panels_mini_panels_cache_get($key);
  if (isset($item->mini_panels_display_cache)) {
    return $item->mini_panels_display_cache;
  }

  $cache = new stdClass();
  $cache->display = $item->display;
  $cache->display->context = ctools_context_load_contexts($item);
  $cache->display->cache_key = 'panels_mini:' . $key;
  $cache->display->storage_type = 'panels_mini';
  // Temporary storage id that's replaced in panels_mini_save().
  $cache->display->storage_id = 'panels_mini';
  $cache->content_types = panels_common_get_allowed_types('panels_mini', $cache->display->context);
  $cache->display_title = TRUE;

  // @TODO support locking
  $cache->locked = FALSE;

  return $cache;
}

/**
 * Store a display edit in progress in the page cache.
 */
function panels_mini_panels_cache_set($key, $cache) {
  list($handler, $item) = _panels_mini_panels_cache_get($key);
  $item->mini_panels_display_cache = $cache;
  $handler->edit_cache_set_key($item, $key);
}

/**
 * Save all changes made to a display using the panels mini UI cache.
 */
function panels_mini_panels_cache_clear($key, $cache) {
  list($handler, $item) = _panels_mini_panels_cache_get($key);
  $handler->edit_cache_clear($item);
}

/**
 * Save all changes made to a display using the panels mini UI cache.
 */
function panels_mini_panels_cache_save($key, $cache) {
  list($handler, $item) = _panels_mini_panels_cache_get($key);
  $item->display = $cache->display;
  panels_mini_save($item);

  $handler->edit_cache_clear($item);
}

/**
 * Break the lock on a panels mini page.
 */
function panels_mini_panels_cache_break_lock($key, $cache) {
}

/**
 * Implements hook_panels_pre_render().
 */
function panels_mini_panels_pre_render($display, $renderer) {
  if (isset($display->owner->table) && $display->owner->table == 'panels_mini' && $renderer instanceof panels_renderer_standard) {
    $renderer->show_empty_layout = FALSE;
  }
}

/**
 * Implementation of hook_panels_dashboard_blocks().
 *
 * Adds mini panels information to the Panels dashboard.
 */
function panels_mini_panels_dashboard_blocks(&$vars) {
  $vars['links']['panels_mini'] = array(
    'title' => l(t('Mini panel'), 'admin/structure/mini-panels/add'),
    'description' => t('Mini panels are small content areas exposed as blocks, for when you need to have complex block layouts or layouts within layouts.'),
    'weight' => -1,
  );

  // Load all mini panels and their displays.
  $panel_minis = panels_mini_load_all();
  $count = 0;
  $rows = array();

  foreach ($panel_minis as $panel_mini) {
    $rows[] = array(
      check_plain($panel_mini->admin_title),
      array(
        'data' => l(t('Edit'), "admin/structure/mini-panels/list/$panel_mini->name/edit"),
        'class' => 'links',
      ),
    );

    // Only show 10.
    if (++$count >= 10) {
      break;
    }
  }

  if ($rows) {
    $content = theme('table', array('rows' => $rows, 'attributes' => array('class' => 'panels-manage')));
  }
  else {
    $content = '<p>' . t('There are no mini panels.') . '</p>';
  }

  $vars['blocks']['panels_mini'] = array(
    'weight' => -100,
    'title' => t('Manage mini panels'),
    'link' => l(t('Go to list'), 'admin/structure/mini-panels'),
    'content' => $content,
    'class' => 'dashboard-mini-panels',
    'section' => 'left',
  );

}

/**
 * Implements template_preprocess_ctools_wizard_trail().
 *
 * Customize the divider used in the CTools wizard to build the edit pages for
 * Mini Panels as a stop-gap measure until the UX can be completely re-done.
 */
function panels_mini_preprocess_ctools_wizard_trail(&$variables) {
  $variables['divider'] = ' | ';
  drupal_add_css(drupal_get_path('module', 'panels_mini') . '/panels_mini.css');
}
