[project/views.git] / views.module

<?php
// $Id$
/**
 * @file
 * Primarily Drupal hooks and global API functions to manipulate views.
 *
 * This is the main module file for Views. The main entry points into
 * this module are views_page() and views_block(), where it handles
 * incoming page and block requests.
 */

/**
 * Advertise the current views api version
 */
function views_api_version() {
  return '3.0-alpha1';
}

/**
 * Views will not load plugins advertising a version older than this.
 */
function views_api_minimum_version() {
  return '2';
}

/**
 * Implement hook_init().
 */
function views_init() {
  drupal_add_css(drupal_get_path('module', 'views') .'/css/views.css');
}

/**
 * Implement hook_theme(). Register views theming functions.
 */
function views_theme($existing, $type, $theme, $path) {
  $path = drupal_get_path('module', 'views');
  include_once $path . '/theme/theme.inc';

  // Some quasi clever array merging here.
  $base = array(
    'file' => 'theme.inc',
    'path' => $path . '/theme',
  );

  // Our extra version of pager from pager.inc
  $hooks['views_mini_pager'] = $base + array(
    'variables' => array('tags' => array(), 'quantity' => 10, 'element' => 0, 'parameters' => array()),
    'pattern' => 'views_mini_pager__',
  );

  $arguments = array(
    'display' => array('view' => NULL),
    'style' => array('view' => NULL, 'options' => NULL, 'rows' => NULL, 'title' => NULL),
    'row' => array('view' => NULL, 'options' => NULL, 'row' => NULL, 'field_alias' => NULL),
  );

  // Default view themes
  $hooks['views_view_field'] = $base + array(
    'pattern' => 'views_view_field__',
    'variables' => array('view' => NULL, 'field' => NULL, 'row' => NULL),
  );

  $plugins = views_fetch_plugin_data();

  // Register theme functions for all style plugins
  foreach ($plugins as $type => $info) {
    foreach ($info as $plugin => $def) {
      if (isset($def['theme'])) {
        $hooks[$def['theme']] = array(
          'pattern' => $def['theme'] . '__',
          'file' => $def['theme file'],
          'path' => $def['theme path'],
          'variables' => $arguments[$type],
        );

        $include = DRUPAL_ROOT . '/' . $def['theme path'] . '/' . $def['theme file'];
        if (file_exists($include)) {
          require_once $include;
        }

        if (!function_exists('theme_' . $def['theme'])) {
          $hooks[$def['theme']]['template'] = drupal_clean_css_identifier($def['theme']);
        }
      }
      if (isset($def['additional themes'])) {
        foreach ($def['additional themes'] as $theme => $theme_type) {
          if (empty($theme_type)) {
            $theme = $theme_type;
            $theme_type = $type;
          }

          $hooks[$theme] = array(
            'pattern' => $theme . '__',
            'file' => $def['theme file'],
            'path' => $def['theme path'],
            'variables' => $arguments[$theme_type],
          );

          if (!function_exists('theme_' . $theme)) {
            $hooks[$theme]['template'] = drupal_clean_css_identifier($theme);
          }
        }
      }
    }
  }

  $hooks['views_exposed_form'] = $base + array(
    'template' => 'views-exposed-form',
    'pattern' => 'views_exposed_form__',
    'render element' => 'form',
  );

  $hooks['views_more'] = $base + array(
    'template' => 'views-more',
    'pattern' => 'views_more__',
    'variables' => array('more_url' => NULL, 'link_text' => 'more'),
  );

  // Add theme suggestions which are part of modules.
  foreach (views_get_module_apis() as $info) {
    if (isset($info['template path'])) {
      $hooks += _views_find_module_templates($hooks, $info['template path']);
    }
  }
  return $hooks;
}

/**
 * Scans a directory of a module for template files.
 *
 * @param $cache
 *   The existing cache of theme hooks to test against.
 * @param $path
 *   The path to search.
 * 
 * @see drupal_find_theme_templates
 */
function _views_find_module_templates($cache, $path) {
  $regex = '/' . '\.tpl\.php' . '$' . '/';

  // Because drupal_system_listing works the way it does, we check for real
  // templates separately from checking for patterns.
  $files = drupal_system_listing($regex, $path, 'name', 0);
  foreach ($files as $template => $file) {
    // Chop off the remaining extensions if there are any. $template already
    // has the rightmost extension removed, but there might still be more,
    // such as with .tpl.php, which still has .tpl in $template at this point.
    if (($pos = strpos($template, '.')) !== FALSE) {
      $template = substr($template, 0, $pos);
    }
    // Transform - in filenames to _ to match function naming scheme
    // for the purposes of searching.
    $hook = strtr($template, '-', '_');
    if (isset($cache[$hook])) {
      $templates[$hook] = array(
        'template' => $template,
        'path' => dirname($file->filename),
        'includes' => isset($cache[$hook]['includes']) ? $cache[$hook]['includes'] : NULL,
      );
    }
    // Ensure that the pattern is maintained from base themes to its sub-themes.
    // Each sub-theme will have their templates scanned so the pattern must be
    // held for subsequent runs.
    if (isset($cache[$hook]['pattern'])) {
      $templates[$hook]['pattern'] = $cache[$hook]['pattern'];
    }
  }

  $patterns = array_keys($files);

  foreach ($cache as $hook => $info) {
    if (!empty($info['pattern'])) {
      // Transform _ in pattern to - to match file naming scheme
      // for the purposes of searching.
      $pattern = strtr($info['pattern'], '_', '-');

      $matches = preg_grep('/^'. $pattern .'/', $patterns);
      if ($matches) {
        foreach ($matches as $match) {
          $file = substr($match, 0, strpos($match, '.'));
          // Put the underscores back in for the hook name and register this pattern.
          $templates[strtr($file, '-', '_')] = array(
            'template' => $file,
            'path' => dirname($files[$match]->filename),
            'variables' => $info['variables'],
            'base hook' => $hook,
            'includes' => isset($info['includes']) ? $info['includes'] : NULL,
          );
        }
      }
    }
  }

  return $templates;
}

/**
 * A theme preprocess function to automatically allow view-based node
 * templates if called from a view.
 *
 * The 'modules/node.views.inc' file is a better place for this, but
 * we haven't got a chance to load that file before Drupal builds the
 * node portion of the theme registry.
 */
function views_preprocess_node(&$vars) {
  // The 'view' attribute of the node is added in template_preprocess_views_view_row_node()
  if (!empty($vars['node']->view) && !empty($vars['node']->view->name)) {
    $vars['view'] = &$vars['node']->view;
    $vars['theme_hook_suggestions'][] = 'node__view__' . $vars['node']->view->name;
    if (!empty($vars['node']->view->current_display)) {
      $vars['theme_hook_suggestions'][] = 'node__view__' . $vars['node']->view->name . '__' . $vars['node']->view->current_display;
    }
  }
}

/**
 * A theme preprocess function to automatically allow view-based node
 * templates if called from a view.
 */
function views_preprocess_comment(&$vars) {
  // The 'view' attribute of the node is added in template_preprocess_views_view_row_comment()
  if (!empty($vars['node']->view) && !empty($vars['node']->view->name)) {
    $vars['view'] = &$vars['node']->view;
    $vars['theme_hook_suggestions'][] = 'comment__view__' . $vars['node']->view->name;
    if (!empty($vars['node']->view->current_display)) {
      $vars['theme_hook_suggestions'][] = 'comment__view__' . $vars['node']->view->name . '__' . $vars['node']->view->current_display;
    }
  }
}

/*
 * Implement hook_permission().
 */
function views_permission() {
  return array(
    'administer views' => array(
      'title' => t('Administer views'),
      'description' => t('Access the views administration pages.'),
    ),
    'access all views' => array(
      'title' => t('Access all views'),
      'description' => t('Bypass access control when accessing views.'),
    ),
  );
}

/**
 * Implement hook_menu().
 */
function views_menu() {
  // Any event which causes a menu_rebuild could potentially mean that the
  // Views data is updated -- module changes, profile changes, etc.
  views_invalidate_cache();
  $items = array();
  $items['views/ajax'] = array(
    'title' => 'Views',
    'page callback' => 'views_ajax',
    'access callback' => TRUE,
    'description' => 'Ajax callback for view loading.',
    'type' => MENU_CALLBACK,
  );
  // Path is not admin/structure/views due to menu complications with the wildcards from
  // the generic ajax callback.
  $items['admin/views/ajax/autocomplete/user'] = array(
    'page callback' => 'views_ajax_autocomplete_user',
    'access callback' => 'user_access',
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK,
    'file' => 'includes/ajax.inc',
  );
  // Define another taxonomy autocomplete because the default one of drupal
  // does not support a vid a argument anymore
  $items['admin/views/ajax/autocomplete/taxonomy'] = array(
    'page callback' => 'views_ajax_autocomplete_taxonomy',
    'access callback' => 'user_access',
    'access arguments' => array('access content'),
    'type' => MENU_CALLBACK,
    'file' => 'includes/ajax.inc',
  );
  return $items;
}

/**
 * Implement hook_menu_alter().
 */
function views_menu_alter(&$callbacks) {
  $our_paths = array();
  $views = views_get_applicable_views('uses hook menu');
  foreach ($views as $data) {
    list($view, $display_id) = $data;
    $result = $view->execute_hook_menu($display_id, $callbacks);
    if (is_array($result)) {
      // The menu system doesn't support having two otherwise
      // identical paths with different placeholders.  So we
      // want to remove the existing items from the menu whose
      // paths would conflict with ours.

      // First, we must find any existing menu items that may
      // conflict.  We use a regular expression because we don't
      // know what placeholders they might use.  Note that we
      // first construct the regex itself by replacing %views_arg
      // in the display path, then we use this constructed regex
      // (which will be something like '#^(foo/%[^/]*/bar)$#') to
      // search through the existing paths.
      $regex = '#^(' . preg_replace('#%views_arg#', '%[^/]*', implode('|', array_keys($result))) . ')$#';
      $matches = preg_grep($regex, array_keys($callbacks));

      // Remove any conflicting items that were found.
      foreach ($matches as $path) {
        // Don't remove the paths we just added!
        if (!isset($our_paths[$path])) {
          unset($callbacks[$path]);
        }
      }
      foreach ($result as $path => $item) {
        if (!isset($callbacks[$path])) {
          // Add a new item, possibly replacing (and thus effectively
          // overriding) one that we removed above.
          $callbacks[$path] = $item;
        }
        else {
          // This item already exists, so it must be one that we added.
          // We change the various callback arguments to pass an array
          // of possible display IDs instead of a single ID.
          $callbacks[$path]['page arguments'][1] = (array)$callbacks[$path]['page arguments'][1];
          $callbacks[$path]['page arguments'][1][] = $display_id;
          $callbacks[$path]['access arguments'][] = $item['access arguments'][0];
          $callbacks[$path]['load arguments'][1] = (array)$callbacks[$path]['load arguments'][1];
          $callbacks[$path]['load arguments'][1][] = $display_id;
        }
        $our_paths[$path] = TRUE;
      }
    }
  }

  // Save memory: Destroy those views.
  foreach ($views as $data) {
    list($view, $display_id) = $data;
    $view->destroy();
  }
}

/**
 * Helper function for menu loading. This will automatically be
 * called in order to 'load' a views argument; primarily it
 * will be used to perform validation.
 *
 * @param $value
 *   The actual value passed.
 * @param $name
 *   The name of the view. This needs to be specified in the 'load function'
 *   of the menu entry.
 * @param $display_id
 *   The display id that will be loaded for this menu item.
 * @param $index
 *   The menu argument index. This counts from 1.
 */
function views_arg_load($value, $name, $display_id, $index) {
  static $views = array();

  // Make sure we haven't already loaded this views argument for a similar menu
  // item elsewhere.
  $key = $name . ':' . $display_id . ':' . $value . ':' . $index;
  if (isset($views[$key])) {
    return $views[$key];
  }

  if ($view = views_get_view($name)) {
    $view->set_display($display_id);
    $view->init_handlers();

    $ids = array_keys($view->argument);

    $indexes = array();
    $path = explode('/', $view->get_path());

    foreach ($path as $id => $piece) {
      if ($piece == '%' && !empty($ids)) {
        $indexes[$id] = array_shift($ids);
      }
    }

    if (isset($indexes[$index])) {
      if (isset($view->argument[$indexes[$index]])) {
        $arg = $view->argument[$indexes[$index]]->validate_argument($value) ? $value : FALSE;
        $view->destroy();

        // Store the output in case we load this same menu item again.
        $views[$key] = $arg;
        return $arg;
      }
    }
    $view->destroy();
  }
}

/**
 * Page callback entry point; requires a view and a display id, then
 * passes control to the display handler.
 */
function views_page() {
  $args = func_get_args();
  $name = array_shift($args);
  $display_id = array_shift($args);

  // Load the view
  if ($view = views_get_view($name)) {
    return $view->execute_display($display_id, $args);
  }

  // Fallback; if we get here no view was found or handler was not valid.
  return drupal_not_found();
}

/**
 * Implement hook_block_info().
 */
function views_block_info() {
  // Try to avoid instantiating all the views just to get the blocks info.
  views_include('cache');
  $cache = views_cache_get('views_block_items', TRUE);
  if ($cache && is_array($cache->data)) {
    return $cache->data;
  }

  $items = array();
  $views = views_get_all_views();
  foreach ($views as $view) {
    // disabled views get nothing.
    if (!empty($view->disabled)) {
      continue;
    }

    $view->init_display();
    foreach ($view->display as $display_id => $display) {

      if (isset($display->handler) && !empty($display->handler->definition['uses hook block'])) {
        $result = $display->handler->execute_hook_block_list();
        if (is_array($result)) {
          $items = array_merge($items, $result);
        }
      }

      if (isset($display->handler) && $display->handler->get_option('exposed_block')) {
        $result = $display->handler->get_special_blocks();
        if (is_array($result)) {
          $items = array_merge($items, $result);
        }
      }
    }
  }

  // block.module has a delta length limit of 32, but our deltas can
  // unfortunately be longer because view names can be 32 and display IDs
  // can also be 32. So for very long deltas, change to md5 hashes.
  $hashes = array();

  // get the keys because we're modifying the array and we don't want to
  // confuse PHP too much.
  $keys = array_keys($items);
  foreach ($keys as $delta) {
    if (strlen($delta) >= 32) {
      $hash = md5($delta);
      $hashes[$hash] = $delta;
      $items[$hash] = $items[$delta];
      unset($items[$delta]);
    }
  }

  // Only save hashes if they have changed.
  $old_hashes = variable_get('views_block_hashes', array());
  if ($hashes != $old_hashes) {
    variable_set('views_block_hashes', $hashes);
  }
  // Save memory: Destroy those views.
  foreach ($views as $view) {
    $view->destroy();
  }

  views_cache_set('views_block_items', $items, TRUE);

  return $items;
}

/**
 * Implement hook_block_view().
 */
function views_block_view($delta) {
  $start = microtime(TRUE);
  // if this is 32, this should be an md5 hash.
  if (strlen($delta) == 32) {
    $hashes = variable_get('views_block_hashes', array());
    if (!empty($hashes[$delta])) {
      $delta = $hashes[$delta];
    }
  }

  // This indicates it's a special one.
  if (substr($delta, 0, 1) == '-') {
    list($nothing, $type, $name, $display_id) = explode('-', $delta);
    // Put the - back on.
    $type = '-' . $type;
    if ($view = views_get_view($name)) {
      if ($view->access($display_id)) {
        $view->set_display($display_id);
        if (isset($view->display_handler)) {
          $output = $view->display_handler->view_special_blocks($type);
          $view->destroy();
          return $output;
        }
      }
      $view->destroy();
    }
  }

  list($name, $display_id) = explode('-', $delta);
  // Load the view
  if ($view = views_get_view($name)) {
    if ($view->access($display_id)) {
      $output = $view->execute_display($display_id);
      $view->destroy();
      return $output;
    }
    $view->destroy();
  }
}

/**
 * Implements hook_flush_caches().
 */
function views_flush_caches() {
  return array('cache_views', 'cache_views_data');
}

/**
 * Implements hook_field_create_instance.
 */
function views_field_create_instance($instance) {
  cache_clear_all('*', 'cache_views', TRUE);
  cache_clear_all('*', 'cache_views_data', TRUE);
}

/**
 * Implements hook_field_update_instance.
 */
function views_field_update_instance($instance, $prior_instance) {
  cache_clear_all('*', 'cache_views', TRUE);
  cache_clear_all('*', 'cache_views_data', TRUE);
}

/**
 * Implements hook_field_delete_instance.
 */
function views_field_delete_instance($instance) {
  cache_clear_all('*', 'cache_views', TRUE);
  cache_clear_all('*', 'cache_views_data', TRUE);
}

/**
 * Invalidate the views cache, forcing a rebuild on the next grab of table data.
 */
function views_invalidate_cache() {
  cache_clear_all('*', 'cache_views', TRUE);
}

/**
 * Access callback to determine if the user can import Views.
 *
 * View imports require an additional access check because they are PHP
 * code and PHP is more locked down than administer views.
 */
function views_import_access() {
  return user_access('administer views') && user_access('use PHP for settings');
}

/**
 * Determine if the logged in user has access to a view.
 *
 * This function should only be called from a menu hook or some other
 * embedded source. Each argument is the result of a call to
 * views_plugin_access::get_access_callback() which is then used
 * to determine if that display is accessible. If *any* argument
 * is accessible, then the view is accessible.
 */
function views_access() {
  $args = func_get_args();
  foreach ($args as $arg) {
    if ($arg === TRUE) {
      return TRUE;
    }

    if (!is_array($arg)) {
      continue;
    }

    list($callback, $arguments) = $arg;
    $arguments = $arguments ? $arguments : array();
    if (function_exists($callback) && call_user_func_array($callback, $arguments)) {
      return TRUE;
    }
  }

  return FALSE;
}

/**
 * Access callback for the views_plugin_access_perm access plugin.
 *
 * Determine if the specified user has access to a view on the basis of
 * permissions. If the $account argument is omitted, the current user
 * is used.
 */
function views_check_perm($perm, $account = NULL) {
  return user_access($perm, $account) || user_access('access all views', $account);
}

/**
 * Access callback for the views_plugin_access_role access plugin.

 * Determine if the specified user has access to a view on the basis of any of
 * the requested roles. If the $account argument is omitted, the current user
 * is used.
 */
function views_check_roles($rids, $account = NULL) {
  global $user;
  $account = isset($account) ? $account : $user;
  $roles = array_keys($account->roles);
  $roles[] = $account->uid ? DRUPAL_AUTHENTICATED_RID : DRUPAL_ANONYMOUS_RID;
  return user_access('access all views', $account) || array_intersect(array_filter($rids), $roles);
}
// ------------------------------------------------------------------
// Functions to help identify views that are running or ran

/**
 * Set the current 'page view' that is being displayed so that it is easy
 * for other modules or the theme to identify.
 */
function &views_set_page_view($view = NULL) {
  static $cache = NULL;
  if (isset($view)) {
    $cache = $view;
  }

  return $cache;
}

/**
 * Find out what, if any, page view is currently in use. Please note that
 * this returns a reference, so be careful! You can unintentionally modify the
 * $view object.
 */
function &views_get_page_view() {
  return views_set_page_view();
}

/**
 * Set the current 'current view' that is being built/rendered so that it is
 * easy for other modules or items in drupal_eval to identify
 */
function &views_set_current_view($view = NULL) {
  static $cache = NULL;
  if (isset($view)) {
    $cache = $view;
  }

  return $cache;
}

/**
 * Find out what, if any, current view is currently in use. Please note that
 * this returns a reference, so be careful! You can unintentionally modify the
 * $view object.
 */
function &views_get_current_view() {
  return views_set_current_view();
}

// ------------------------------------------------------------------
// Include file helpers

/**
 * Include views .inc files as necessary.
 */
function views_include($file) {
  module_load_include('inc', 'views', "includes/$file");
}

/**
 * Load views files on behalf of modules.
 */
function views_module_include($file, $reset = FALSE) {
  foreach (views_get_module_apis($reset) as $module => $info) {
    if (file_exists(DRUPAL_ROOT . "/$info[path]/$module.$file")) {
      require_once DRUPAL_ROOT . "/$info[path]/$module.$file";
    }
  }
}

/**
 * Get a list of modules that support the current views API.
 */
function views_get_module_apis($reset = FALSE) {
  static $cache = NULL;
  if (!isset($cache) || $reset) {
    $cache = array();
    foreach (module_implements('views_api') as $module) {
      $info = module_invoke($module, 'views_api');
      if (version_compare($info['api'], views_api_minimum_version(), '>=') &&
          version_compare($info['api'], views_api_version(), '<=')) {
        if (!isset($info['path'])) {
          $info['path'] = drupal_get_path('module', $module);
        }
        $cache[$module] = $info;
      }
    }
  }

  return $cache;
}

/**
 * Include views .css files.
 */
function views_add_css($file) {
  // We set preprocess to FALSE because we are adding the files conditionally,
  // and we don't want to generate duplicate cache files.
  // TODO: at some point investigate adding some files unconditionally and
  // allowing preprocess.
  drupal_add_css(drupal_get_path('module', 'views') . "/css/$file.css", array('preprocess' => FALSE));
}

/**
 * Include views .js files.
 */
function views_add_js($file) {
  // If javascript has been disabled by the user, never add js files.
  if (variable_get('views_no_javascript', FALSE)) {
    return;
  }

  static $base = TRUE, $ajax = TRUE;
  if ($base) {
    drupal_add_js(drupal_get_path('module', 'views') . "/js/base.js");
    $base = FALSE;
  }
  if ($ajax && $file == 'ajax') {
    drupal_add_js('misc/ajax.js', array('group' => JS_LIBRARY));
    $ajax = TRUE;
  }
  drupal_add_js(drupal_get_path('module', 'views') . "/js/$file.js");
}

/**
 * Load views files on behalf of modules.
 */
function views_include_handlers($reset = FALSE) {
  static $finished = FALSE;
  // Ensure this only gets run once.
  if ($finished && !$reset) {
    return;
  }

  views_include('base');
  views_include('handlers');
  views_include('cache');
  views_include('plugins');
  _views_include_handlers();
  $finished = TRUE;
}

/**
 * Load default views files on behalf of modules.
 */
function views_include_default_views($reset = FALSE) {
  static $finished = FALSE;
  // Ensure this only gets run once.
  if ($finished && !$reset) {
    return;
  }

  // Default views hooks may be in the normal handler file,
  // or in a separate views_default file at the discretion of
  // the module author.
  views_include_handlers($reset);

  _views_include_default_views($reset);
  $finished = TRUE;
}

// -----------------------------------------------------------------------
// Views handler functions

/**
 * Fetch a handler from the data cache.
 *
 * @param $table
 *   The name of the table this handler is from.
 * @param $field
 *   The name of the field this handler is from.
 * @param $key
 *   The type of handler. i.e, sort, field, argument, filter, relationship
 * @param $override
 *   Override the actual handler object with this class. Used for
 *   aggregation when the handler is redirected to the aggregation
 *   handler.
 *
 * @return
 *   An instance of a handler object. May be views_handler_broken.
 */
function views_get_handler($table, $field, $key, $override = NULL) {
  $data = views_fetch_data($table);
  $handler = NULL;

  if (isset($data[$field][$key])) {
    // Set up a default handler:
    if (empty($data[$field][$key]['handler'])) {
      $data[$field][$key]['handler'] = 'views_handler_' . $key;
    }

    if ($override) {
      $data[$field][$key]['override handler'] = $override;
    }

    $handler = _views_prepare_handler($data[$field][$key], $data, $field);
  }

  if ($handler) {
    return $handler;
  }

  // DEBUG -- identify missing handlers
  debug("Missing handler: $table $field $key");
  $broken = array(
    'title' => t('Broken handler @table.@field', array('@table' => $table, '@field' => $field)),
    'handler' => 'views_handler_' . $key . '_broken',
    'table' => $table,
    'field' => $field,
  );
  return _views_create_handler($broken);
}

/**
 * Fetch Views' data from the cache
 */
function views_fetch_data($table = NULL, $reset = FALSE) {
  views_include('cache');
  return _views_fetch_data($table, $reset);
}

// -----------------------------------------------------------------------
// Views plugin functions

/**
 * Fetch the plugin data from cache.
 */
function views_fetch_plugin_data($type = NULL, $plugin = NULL, $reset = FALSE) {
  views_include('cache');
  return _views_fetch_plugin_data($type, $plugin, $reset);
}

/**
 * Get a handler for a plugin
 */
function views_get_plugin($type, $plugin, $reset = FALSE) {
  views_include('handlers');
  $definition = views_fetch_plugin_data($type, $plugin, $reset);
  if (!empty($definition)) {
    return _views_create_handler($definition, $type);
  }
}

// -----------------------------------------------------------------------
// Views database functions

/**
 * Get a view from the default views defined by modules.
 *
 * Default views are cached per-language.  This function will rescan the
 * default_views hook if necessary.
 *
 * @param $view_name
 *   The name of the view to load.
 * @return
 *   A view object or NULL if it is not available.
 */
function &views_get_default_view($view_name, $reset = FALSE) {
  $null = NULL;

  // Attempt to load individually cached view from cache.
  views_include('cache');
  if (!$reset) {
    $data = views_cache_get("views_default:{$view_name}", TRUE);
    if (isset($data->data) && is_object($data->data)) {
      return $data->data;
    }
  }

  // Otherwise, allow entire cache to be rebuilt.
  $cache = views_discover_default_views($reset);
  if (isset($cache[$view_name])) {
    return $cache[$view_name];
  }
  return $null;
}

/**
 * Create an empty view to work with.
 *
 * @return
 *   A fully formed, empty $view object. This object must be populated before
 *   it can be successfully saved.
 */
function views_new_view() {
  views_include('view');
  $view = new view();
  $view->vid = 'new';
  $view->add_display('default');

  return $view;
}

/**
 * Scan all modules for default views and rebuild the default views cache.
 *
 * @return An associative array of all known default views.
 */
function views_discover_default_views($reset = FALSE) {
  static $cache = array();

  if (empty($cache) || $reset) {
    views_include('cache');
    $cache = _views_discover_default_views($reset);
  }
  return $cache;
}

/**
 * Return a list of all views and display IDs that have a particular
 * setting in their display's plugin settings.
 *
 * @return
 * @code
 * array(
 *   array($view, $display_id),
 *   array($view, $display_id),
 * );
 * @endcode
 */
function views_get_applicable_views($type) {
  // @todo: Use a smarter flagging system so that we don't have to
  // load every view for this.
  $result = array();
  $views = views_get_all_views();

  foreach ($views as $view) {
    // Skip disabled views.
    if (!empty($view->disabled)) {
      continue;
    }

    if (empty($view->display)) {
      // Skip this view as it is broken.
      vsm(t("Skipping broken view @view", array('@view' => $view->name)));
      continue;
    }

    // Loop on array keys because something seems to muck with $view->display
    // a bit in PHP4.
    foreach (array_keys($view->display) as $id) {
      $plugin = views_fetch_plugin_data('display', $view->display[$id]->display_plugin);
      if (!empty($plugin[$type])) {
        // This view uses hook menu. Clone it so that different handlers
        // don't trip over each other, and add it to the list.
        $v = $view->clone_view();
        if ($v->set_display($id)) {
          $result[] = array($v, $id);
        }
        // In PHP 4.4.7 and presumably earlier, if we do not unset $v
        // here, we will find that it actually overwrites references
        // possibly due to shallow copying issues.
        unset($v);
      }
    }
  }
  return $result;
}

/**
 * Return an array of all views as fully loaded $view objects.
 *
 * @param $reset
 *   If TRUE, reset the static cache forcing views to be reloaded.
 */
function views_get_all_views($reset = FALSE) {
  static $views = array();

  if (empty($views) || $reset) {
    $views = array();

    // First, get all applicable views.
    views_include('view');
    $views = view::load_views();

    // Get all default views.
    $status = variable_get('views_defaults', array());

    foreach (views_discover_default_views($reset) as $view) {
      // Determine if default view is enabled or disabled.
      if (isset($status[$view->name])) {
        $view->disabled = $status[$view->name];
      }

      // If overridden, also say so.
      if (!empty($views[$view->name])) {
        $views[$view->name]->type = t('Overridden');
      }
      else {
        $view->type = t('Default');
        $views[$view->name] = $view;
      }
    }

  }
  return $views;
}

/**
 * Get a view from the database or from default views.
 *
 * This function is just a static wrapper around views::load(). This function
 * isn't called 'views_load()' primarily because it might get a view
 * from the default views which aren't technically loaded from the database.
 *
 * @param $name
 *   The name of the view.
 * @param $reset
 *   If TRUE, reset this entry in the load cache.
 * @return $view
 *   A reference to the $view object. Use $reset if you're sure you want
 *   a fresh one.
 */
function views_get_view($name, $reset = FALSE) {
  views_include('view');
  $view = view::load($name, $reset);
  $default_view = views_get_default_view($name, $reset);

   // The view does not exist.
  if (empty($view) && empty($default_view)) {
    return;
  }
  // The view is defined in code.
  elseif (empty($view) && !empty($default_view)) {
    $status = variable_get('views_defaults', array());
    if (isset($status[$default_view->name])) {
      $default_view->disabled = $status[$default_view->name];
    }
    $default_view->type = t('Default');
    return $default_view->clone_view();
  }
  // The view is overriden/defined in the database.
  elseif (!empty($view) && !empty($default_view)) {
    $view->type = t('Overridden');
  }

  return $view->clone_view();
}

// ------------------------------------------------------------------
// Views debug helper functions

/**
 * Debug messages
 */
function vsm($message) {
  if (module_exists('devel')) {
    dsm($message);
  }
}

function views_trace() {
  $message = '';
  foreach (debug_backtrace() as $item) {
    if (!empty($item['file']) && !in_array($item['function'], array('vsm_trace', 'vpr_trace', 'views_trace'))) {
      $message .= basename($item['file']) . ": " . (empty($item['class']) ? '' : ($item['class'] . '->')) . "$item[function] line $item[line]" . "\n";
    }
  }
  return $message;
}

function vsm_trace() {
  vsm(views_trace());
}

function vpr_trace() {
  dpr(views_trace());
}

// ------------------------------------------------------------------
// Exposed widgets form

/**
 * Form builder for the exposed widgets form.
 *
 * Be sure that $view and $display are references.
 */
function views_exposed_form($form, &$form_state) {
  // Don't show the form when batch operations are in progress.
  if ($batch = batch_get() && isset($batch['current_set'])) {
    return array(
      // Set the theme callback to be nothing to avoid errors in template_preprocess_views_exposed_form().
      '#theme' => '',
    );
  }

  // Make sure that we validate because this form might be submitted
  // multiple times per page.
  $form_state['must_validate'] = TRUE;
  $view = &$form_state['view'];
  $display = &$form_state['display'];

  $form_state['input'] = $view->get_exposed_input();

  // Let form plugins know this is for exposed widgets.
  $form_state['exposed'] = TRUE;
  // Check if the form was already created
  if ($cache = views_exposed_form_cache($view->name, $view->current_display)) {
    return $cache;
  }

  $form['#info'] = array();

  if (!variable_get('clean_url', FALSE)) {
    $form['q'] = array(
      '#type' => 'hidden',
      '#value' => $view->get_url(),
    );
  }

  // Go through each handler and let it generate its exposed widget.
  foreach ($view->display_handler->handlers as $type => $value) {
    foreach ($view->$type as $id => $handler) {
      if ($handler->can_expose() && $handler->is_exposed()) {
        $handler->exposed_form($form, $form_state);
        if ($info = $handler->exposed_info()) {
          $form['#info']["$type-$id"] = $info;
        }
      }
    }
  }

  $form['submit'] = array(
    '#name' => '', // prevent from showing up in $_GET.
    '#type' => 'submit',
    '#value' => t('Apply'),
    '#id' => drupal_html_id('edit-submit-' . $view->name),
  );

  $form['#action'] = url($view->get_url());
  $form['#theme'] = views_theme_functions('views_exposed_form', $view, $display);
  $form['#id'] = drupal_clean_css_identifier('views_exposed_form-' . check_plain($view->name) . '-' . check_plain($display->id));
//  $form['#attributes']['class'] = array('views-exposed-form');

  // If using AJAX, we need the form plugin.
  if ($view->use_ajax) {
    drupal_add_js('misc/jquery.form.js', array('group' => JS_LIBRARY));
  }
  ctools_include('dependent');

  $exposed_form_plugin = $form_state['exposed_form_plugin'];
  $exposed_form_plugin->exposed_form_alter($form, $form_state);

  // Save the form
  views_exposed_form_cache($view->name, $view->current_display, $form);

  return $form;
}

/**
 * Validate handler for exposed filters
 */
function views_exposed_form_validate(&$form, &$form_state) {
  foreach (array('field', 'filter') as $type) {
    $handlers = &$form_state['view']->$type;
    foreach ($handlers as $key => $handler) {
      $handlers[$key]->exposed_validate($form, $form_state);
    }
  }
  $exposed_form_plugin = $form_state['exposed_form_plugin'];
  $exposed_form_plugin->exposed_form_validate($form, $form_state);
}

/**
 * Submit handler for exposed filters
 */
function views_exposed_form_submit(&$form, &$form_state) {
  foreach (array('field', 'filter') as $type) {
    $handlers = &$form_state['view']->$type;
    foreach ($handlers as $key => $info) {
      $handlers[$key]->exposed_submit($form, $form_state);
    }
  }
  $form_state['view']->exposed_data = $form_state['values'];
  $form_state['view']->exposed_raw_input = array();


  $exclude = array('q', 'submit', 'form_build_id', 'form_id', 'form_token', 'exposed_form_plugin', '');
  $exposed_form_plugin = $form_state['exposed_form_plugin'];
  $exposed_form_plugin->exposed_form_submit($form, $form_state, $exclude);

  foreach ($form_state['values'] as $key => $value) {
    if (!in_array($key, $exclude)) {
      $form_state['view']->exposed_raw_input[$key] = $value;
    }
  }
}

/**
 * Save the Views exposed form for later use.
 *
 * @param $views_name
 *   String. The views name.
 * @param $display_name
 *   String. The current view display name.
 * @param $form_output
 *   Array (optional). The form structure. Only needed when inserting the value.
 * @return
 *   Array. The form structure, if any. Otherwise, return FALSE.
 */
function views_exposed_form_cache($views_name, $display_name, $form_output = NULL) {
  static $views_exposed;

  // Save the form output
  if (!empty($form_output)) {
    $views_exposed[$views_name][$display_name] = $form_output;
    return;
  }

  // Return the form output, if any
  return empty($views_exposed[$views_name][$display_name]) ? FALSE : $views_exposed[$views_name][$display_name];
}

// ------------------------------------------------------------------
// Misc helpers

/**
 * Build a list of theme function names for use most everywhere.
 */
function views_theme_functions($hook, $view, $display = NULL) {
  require_once DRUPAL_ROOT . '/' . drupal_get_path('module', 'views') . "/theme/theme.inc";
  return _views_theme_functions($hook, $view, $display);
}

/**
 * Substitute current time; this works with cached queries.
 */
function views_views_query_substitutions($view) {
  global $language;
  return array(
    '***CURRENT_VERSION***' => VERSION,
    '***CURRENT_TIME***' => REQUEST_TIME,
    '***CURRENT_LANGUAGE***' => $language->language,
    '***DEFAULT_LANGUAGE***' => language_default('language'),
    '***NO_LANGUAGE***' => '',
  );
}

/**
 * Implements hook_query_TAG_alter().
 *
 * This is the hook_query_alter() for queries tagged by Views and is used to
 * add in substitutions from hook_views_query_substitutions().
 */
function views_query_views_alter(QueryAlterableInterface $query) {
  $substitutions = $query->getMetaData('views_substitutions');
  $tables =& $query->getTables();
  $where =& $query->conditions();

  // Replaces substitions in tables.
  foreach ($tables as $table_name => $table_metadata) {
    foreach ($table_metadata['arguments'] as $replacement_key => $value) {
      if (isset($substitutions[$value])) {
        $tables[$table_name]['arguments'][$replacement_key] = $substitutions[$value];
      }
    }
  }

  // Replaces substitions in filter criterias.
  _views_query_tag_alter_condition($query, $where, $substitutions);
}

/**
 * Replaces the substitutions recursive foreach condition.
 */
function _views_query_tag_alter_condition(QueryAlterableInterface $query, &$conditions, $substitutions) {
  foreach ($conditions as $condition_id => &$condition) {
    if (is_numeric($condition_id)) {
      if (is_string($condition['field'])) {
        $condition['field'] = str_replace(array_keys($substitutions), array_values($substitutions), $condition['field']);
      }
      elseif (is_object($condition['field'])) {
        $sub_conditions =& $condition['field']->conditions();
        _views_query_tag_alter_condition($query, $sub_conditions, $substitutions);
      }
      // $condition['value'] is a subquery so alter the subquery recursive.
      // Therefore take sure to get the metadata of the main query.
      if (is_object($condition['value'])) {
        $subquery = $condition['value'];
        $subquery->addMetaData('views_substitutions', $query->getMetaData('views_substitutions'));
        views_query_views_alter($condition['value']);
      }
      elseif (isset($condition['value'])) {
        $condition['value'] = str_replace(array_keys($substitutions), array_values($substitutions), $condition['value']);
      }
    }
  }
}

/**
 * Embed a view using a PHP snippet.
 *
 * This function is meant to be called from PHP snippets, should one wish to
 * embed a view in a node or something. It's meant to provide the simplest
 * solution and doesn't really offer a lot of options, but breaking the function
 * apart is pretty easy, and this provides a worthwhile guide to doing so.
 *
 * Note that this function does NOT display the title of the view. If you want
 * to do that, you will need to do what this function does manually, by
 * loading the view, getting the preview and then getting $view->get_title().
 *
 * @param $name
 *   The name of the view to embed.
 * @param $display_id
 *   The display id to embed. If unsure, use 'default', as it will always be
 *   valid. But things like 'page' or 'block' should work here.
 * @param ...
 *   Any additional parameters will be passed as arguments.
 */
function views_embed_view($name, $display_id = 'default') {
  $args = func_get_args();
  array_shift($args); // remove $name
  if (count($args)) {
    array_shift($args); // remove $display_id
  }

  $view = views_get_view($name);
  if (!$view || !$view->access($display_id)) {
    return;
  }

  return $view->preview($display_id, $args);
}

/**
* Get the result of a view.
*
* @param string $name
*      The name of the view to retrieve the data from.
* @param string $display_id
*      The display id. On the edit page for the view in question, you'll find
*      a list of displays at the left side of the control area. "Defaults"
*      will be at the top of that list. Hover your cursor over the name of the
*      display you want to use. An URL will appear in the status bar of your
*      browser. This is usually at the bottom of the window, in the chrome.
*      Everything after #views-tab- is the display ID, e.g. page_1.
 * @param ...
 *   Any additional parameters will be passed as arguments.
* @return
*      array
*          An array containing an object for each view item.
*/
function views_get_view_result($name, $display_id = NULL) {
  $args = func_get_args();
  array_shift($args); // remove $name
  if (count($args)) {
    array_shift($args); // remove $display_id
  }

  $view = views_get_view($name);
  if (is_object($view)) {
    if (is_array($args)) {
      $view->set_arguments($args);
    }
    if (is_string($display_id)) {
      $view->set_display($display_id);
    }
    else {
      $view->init_display();
    }
    $view->pre_execute();
    $view->execute();
    return $view->result;
  }
  else {
    return array();
  }
}

/**
 * Export a field.
 */
function views_var_export($var, $prefix = '', $init = TRUE) {
  if (is_array($var)) {
    if (empty($var)) {
      $output = 'array()';
    }
    else {
      $output = "array(\n";
      foreach ($var as $key => $value) {
        $output .= "  " . views_var_export($key, '', FALSE) . " => " . views_var_export($value, '  ', FALSE) . ",\n";
      }
      $output .= ')';
    }
  }
  elseif (is_bool($var)) {
    $output = $var ? 'TRUE' : 'FALSE';
  }
  elseif (is_string($var) && strpos($var, "\n") !== FALSE) {
    // Replace line breaks in strings with a token for replacement
    // at the very end. This protects multi-line strings from
    // unintentional indentation.
    $var = str_replace("\n", "***BREAK***", $var);
    $output = var_export($var, TRUE);
  }
  else {
    $output = var_export($var, TRUE);
  }

  if ($prefix) {
    $output = str_replace("\n", "\n$prefix", $output);
  }

  if ($init) {
    $output = str_replace("***BREAK***", "\n", $output);
  }

  return $output;
}

/**
 * Implement hook_views_exportables().
 */
function views_views_exportables($op = 'list', $views = NULL, $name = 'foo') {
  $all_views = views_get_all_views();
  if ($op == 'list') {

    foreach ($all_views as $name => $view) {
      // in list, $views is a list of tags.
      if (empty($views) || in_array($view->tag, $views)) {
        $return[$name] = array(
          'name' => check_plain($name),
          'desc' => check_plain($view->description),
          'tag' => check_plain($view->tag)
        );
      }
    }
    return $return;
  }

  if ($op == 'export') {
    $code = "/**\n";
    $code .= " * Implement hook_views_default_views().\n";
    $code .= " */\n";
    $code .= "function " . $name . "_views_default_views() {\n";
    foreach ($views as $view => $truth) {
      $code .= "  /*\n";
      $code .= "   * View " . var_export($all_views[$view]->name, TRUE) . "\n";
      $code .= "   */\n";
      $code .= $all_views[$view]->export('  ');
      $code .= '  $views[$view->name] = $view;' . "\n\n";
    }
    $code .= "  return \$views;\n";
    $code .= "}\n";

    return $code;
  }
}

/**
 * #process callback to see if we need to check_plain() the options.
 *
 * Since FAPI is inconsistent, the #options are sanitized for you in all cases
 * _except_ checkboxes. We have form elements that are sometimes 'select' and
 * sometimes 'checkboxes', so we need decide late in the form rendering cycle
 * if the options need to be sanitized before they're rendered. This callback
 * inspects the type, and if it's still 'checkboxes', does the sanitation.
 */
function views_process_check_options($element, &$form_state) {
  if ($element['#type'] == 'checkboxes' || $element['#type'] == 'checkbox') {
    $element['#options'] = array_map('check_plain', $element['#options']);
  }
  return $element;
}

/**
 * Trim the field down to the specified length.
 *
 * @param $alter
 *   - max_length: Maximum lenght of the string, the rest gets truncated.
 *   - word_boundary: Trim only on a word boundary.
 *   - ellipsis: Trim only on a word boundary.
 *   - html: Take sure that the html is correct.
 *
 * @param $value
 *   The string which should be trimmed.
 */
function views_trim_text($alter, $value) {
  if (drupal_strlen($value) > $alter['max_length']) {
    $value = drupal_substr($value, 0, $alter['max_length']);
    // TODO: replace this with cleanstring of ctools
    if (!empty($alter['word_boundary'])) {
      $regex = "(.*)\b.+";
      if (function_exists('mb_ereg')) {
        mb_regex_encoding('UTF-8');
        $found = mb_ereg($regex, $value, $matches);
      }
      else {
        $found = preg_match("/$regex/us", $value, $matches);
      }
      if ($found) {
        $value = $matches[1];
      }
    }
    // Remove scraps of HTML entities from the end of a strings
    $value = rtrim(preg_replace('/(?:<(?!.+>)|&(?!.+;)).*$/us', '', $value));

    if (!empty($alter['ellipsis'])) {
      $value .= '...';
    }
  }
  if (!empty($alter['html'])) {
    $value = _filter_htmlcorrector($value);
  }

  return $value;
}