<?php
// $Id: features.module,v 1.1.2.63 2010-02-07 05:04:43 yhahn Exp $

/**
 * @file
 * Module file for the features module, which enables the capture and
 * management of features in Drupal. A feature is a collection of Drupal
 * entities which taken together statisfy a certain use-case.
 */

define('FEATURES_MODULE_ENABLED', 1);
define('FEATURES_MODULE_DISABLED', 0);
define('FEATURES_MODULE_MISSING', -1);

define('FEATURES_REBUILDABLE', -1);
define('FEATURES_DEFAULT', 0);
define('FEATURES_OVERRIDDEN', 1);
define('FEATURES_NEEDS_REVIEW', 2);
define('FEATURES_REBUILDING', 3);

// Duration of rebuild semaphore: 10 minutes.
define('FEATURES_SEMAPHORE_TIMEOUT', 10 * 60);

/**
 * Components with this 'default_file' flag will have exports written to the
 * common defaults file 'MODULENAME.defaults.inc'. This is the default
 * behavior.
 */
define('FEATURES_DEFAULTS_INCLUDED_COMMON', 0);

/**
 * Components with this 'default_file' flag will have exports written to a
 * defaults based on the component name like 'MODULENAME.features.COMPONENT-NAME.inc'.
 */
define('FEATURES_DEFAULTS_INCLUDED', 1);

/**
 * Components with this 'default_file' flag must specify a filename for thier
 * exports. Additionally a stub will NOT be written to 'MODULENAME.features.inc'
 * allowing the file to be included directly by the implementing module.
 */
define('FEATURES_DEFAULTS_CUSTOM', 2);

/**
 * Components with this 'duplicates' flag may not have multiple features provide the
 * same component key in their info files. This is the default behavior.
 */
define('FEATURES_DUPLICATES_CONFLICT', 0);

/**
 * Components with this 'duplicates' flag are allowed to have multiple features
 * provide the same component key in their info files.
 */
define('FEATURES_DUPLICATES_ALLOWED', 1);

/**
 * Implementation of hook_menu().
 */
function features_menu() {
  $items = array();
  $items['admin/build/features'] = array(
    'title' => 'Features',
    'description' => 'Manage features.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('features_admin_form'),
    'type' => MENU_NORMAL_ITEM,
    'file' => 'features.admin.inc',
  );
  $items['admin/build/features/cleanup'] = array(
    'title' => 'Cleanup',
    'description' => 'Detect and disable any orphaned feature dependencies.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('features_cleanup_form', 4),
    'type' => MENU_CALLBACK,
    'file' => 'features.admin.inc',
    'weight' => 1,
  );
  $items['admin/build/features/manage'] = array(
    'title' => 'Manage',
    'description' => 'Enable and disable features.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('features_admin_form'),
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'file' => 'features.admin.inc',
  );
  $items['admin/build/features/create'] = array(
    'title' => 'Create feature',
    'description' => 'Create a new feature.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('features_export_form'),
    'access callback' => 'user_access',
    'access arguments' => array('administer features'),
    'type' => MENU_LOCAL_TASK,
    'file' => "features.admin.inc",
    'weight' => 10,
  );
  $items['admin/build/features/export/populate'] = array(
    'title' => 'Populate feature',
    'description' => 'AHAH callback to populate a feature from selected components.',
    'page callback' => 'features_export_build_form_populate',
    'page arguments' => array(),
    'access callback' => 'user_access',
    'access arguments' => array('administer features'),
    'type' => MENU_CALLBACK,
    'file' => "features.admin.inc",
  );
  $items['admin/build/features/%feature'] = array(
    'title callback' => 'features_get_feature_title',
    'title arguments' => array(3),
    'description' => 'Display components of a feature.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('features_admin_components', 3),
    'load arguments' => array(3, TRUE),
    'access callback' => 'user_access',
    'access arguments' => array('administer features'),
    'type' => MENU_CALLBACK,
    'file' => 'features.admin.inc',
  );
  $items['admin/build/features/%feature/view'] = array(
    'title' => 'View',
    'description' => 'Display components of a feature.',
    'access callback' => 'user_access',
    'access arguments' => array('administer features'),
    'type' => MENU_DEFAULT_LOCAL_TASK,
    'weight' => -10,
  );
  $items['admin/build/features/%feature/recreate'] = array(
    'title' => 'Recreate',
    'description' => 'Recreate an existing feature.',
    'page callback' => 'drupal_get_form',
    'page arguments' => array('features_export_form', 3),
    'load arguments' => array(3, TRUE),
    'access callback' => 'user_access',
    'access arguments' => array('administer features'),
    'type' => MENU_LOCAL_TASK,
    'file' => "features.admin.inc",
    'weight' => 11,
  );
  if (module_exists('diff')) {
    $items['admin/build/features/%feature/diff'] = array(
      'title' => 'Review overrides',
      'description' => 'Compare default and current feature.',
      'page callback' => 'features_feature_diff',
      'page arguments' => array(3, 5),
      'load arguments' => array(3, TRUE),
      'access callback' => 'features_access_override_actions',
      'access arguments' => array(3),
      'type' => MENU_LOCAL_TASK,
      'file' => 'features.admin.inc',
    );
  }
  $items['admin/build/features/%feature/status'] = array(
    'title' => 'Status',
    'description' => 'Javascript status call back.',
    'page callback' => 'features_feature_status',
    'page arguments' => array(3),
    'load arguments' => array(3, TRUE),
    'access callback' => 'user_access',
    'access arguments' => array('administer features'),
    'type' => MENU_CALLBACK,
    'file' => 'features.admin.inc',
  );
  foreach ($items as $path => $item) {
    if (!isset($item['access callback'])) {
      $items[$path]['access callback'] = 'user_access';
      $items[$path]['access arguments'] = array('manage features');
    }
  }
  return $items;
}

/**
 * Implementation of hook_menu_alter().
 */
function features_menu_alter(&$cache) {
  // Collect exported menu items and graft them into the features menu.
  $items = module_invoke_all('menu_default_items');
  drupal_alter('menu_default_items', $items);

  foreach ($items as $item) {
    if (!empty($item['path'])) {
      $path = $item['path'];
      unset($item['path']);
      if (!empty($cache[$path])) {
        $cache[$path] = array_merge($cache[$path], $item);
        $cache[$path]['type'] = MENU_NORMAL_ITEM;
        $cache[$path]['menu_name'] = 'features';
      }
    }
  }
}

/**
 *  Implementation of hook_theme().
 */
function features_theme() {
  $base = array(
    'path' => drupal_get_path('module', 'features') .'/theme',
    'file' => 'theme.inc',
  );

  $items = array();
  $items['features_components'] =
  $items['features_component_key'] =
  $items['features_component_list'] =
  $items['features_form_buttons'] =
  $items['features_form_components'] =
  $items['features_form_export'] =
  $items['features_form_package'] =
  $items['features_module_status'] =
  $items['features_storage_link'] = $base;

  $items['features_admin_components'] = array(
    'arguments' => array('form' => NULL),
    'template' => 'features-admin-components',
  ) + $base;

  $items['features_form'] = array(
    'arguments' => array('form' => NULL),
    'template' => 'features-form',
  ) + $base;

  return $items;
}

/**
 * Implementation of hook_flush_caches().
 */
function features_flush_caches() {
  features_rebuild();
  features_get_modules(NULL, TRUE);
  return array();
}

/**
 * Implementation of hook_form().
 */
function features_form($node, $form_state) {
  return node_content_form($node, $form_state);
}

/**
 * Implemenation of hook_access()
 */
function features_access($op, $node, $account) {
  return node_content_access($op, $node, $account);
}

/**
 * Implementation of hook_perm().
 */
function features_perm() {
  $perms = array('administer features', 'manage features');
  // Generate permissions for any default node types provided by features.
  foreach (node_get_types() as $type) {
    if ($type->module == 'features') {
      $name = check_plain($type->type);
      $perms[] = 'create '. $name .' content';
      $perms[] = 'delete own '. $name .' content';
      $perms[] = 'delete any '. $name .' content';
      $perms[] = 'edit own '. $name .' content';
      $perms[] = 'edit any '. $name .' content';
    }
  }
  return $perms;
}

/**
 * Load includes for any modules that implement the features API and
 * load includes for those provided by features.
 */
function features_include() {
  // Check for implementing modules and make necessary inclusions.
  foreach (module_implements('features_api') as $module) {
    $info = module_invoke($module, 'features_api');
    foreach ($info as $component) {
      if (isset($component['file'])) {
        require_once $component['file'];
      }
    }
  }

  // Always load the menu module include to be able to deal with menu items.
  module_load_include('inc', 'features', "includes/features.menu");

  // Features provides integration on behalf of these modules.
  // Note that ctools is placed last because it implements hooks "dynamically" for other modules.
  $modules = array('block', 'content', 'context', 'fieldgroup', 'filter', 'imagecache', 'node', 'user', 'views', 'ctools');

  foreach (array_filter($modules, 'module_exists') as $module) {
    if (!module_hook($module, 'features_api')) {
      module_load_include('inc', 'features', "includes/features.$module");
    }
  }

  // Clear static cache, since we've now included new implementers.
  module_implements('features_api', FALSE, TRUE);
}

/**
 * Feature object loader.
 */
function feature_load($name, $reset = FALSE) {
  return features_get_features($name, $reset);
}

/**
 * Return a module 'object' including .info information.
 *
 * @param $name
 *   The name of the module to retrieve information for. If ommitted,
 *   an array of all available modules will be returned.
 * @param $reset
 *   Whether to reset the cache.
 *
 * @return
 *   If a module is request (and exists) a module object is returned. If no
 *   module is requested info for all modules is returned.
 */
function features_get_modules($name = NULL, $reset = FALSE) {
  return features_get_info('module', $name, $reset);
}

/**
 * Returns the array of supported components.
 *
 * @param $feature_source
 *   If set to to TRUE return feature sources only.
 * @return An array of component labels keyed by the component names.
 */
function features_get_components($feature_source = FALSE) {
  features_include();

  $components = array();
  foreach (module_implements('features_api') as $module) {
    $info = module_invoke($module, 'features_api');

    if ($feature_source) {
      // Gather only components that are declared as feature sources.
      foreach ($info as $k => $v) {
        if ($v['feature_source']) {
          $components[$k] = $v;
        }
      }
    }
    else {
      $components = array_merge($components, $info);
    }
  }

  return $components;
}

/**
 * Like module_invoke() but for arbitrary callback base names.
 */
function features_invoke() {
  $args = func_get_args();
  $base = $args[0];
  $hook = $args[1];
  unset($args[0], $args[1]);
  $function = $base .'_'. $hook;
  if (features_hook($base, $hook)) {
    return call_user_func_array($function, $args);
  }
}

/**
 * Like module_invoke_all() but for arbitrary callback base names.
 */
function features_invoke_all() {
  $args = func_get_args();
  $hook = $args[0];
  unset($args[0]);
  $return = array();
  foreach (features_get_components() as $component => $info) {
    $result = features_invoke($component, $hook);
    if (isset($result) && is_array($result)) {
      $return = array_merge_recursive($return, $result);
    }
    else if (isset($result)) {
      $return[] = $result;
    }
  }
  return $return;
}

/**
 * Like module_hook() but for arbitrary callback base names.
 */
function features_hook($base, $hook) {
  return function_exists($base .'_'. $hook);
}

/**
 * Enables and installs an array of modules, ignoring those
 * already enabled & installed. Consider this a helper or
 * extension to drupal_install_modules().
 *
 * @param $modules
 *   An array of modules to install.
 * @param $reset
 *   Clear the module info cache.
 */
function features_install_modules($modules) {
  module_load_include('inc', 'features', 'features.export');
  $files = module_rebuild_cache();

  // Build maximal list of dependencies.
  $install = array();
  foreach ($modules as $name) {
    if ($file = $files[$name]) {
      $install[] = $name;
      if (!empty($file->info['dependencies'])) {
        $install = array_merge($install, _features_export_maximize_dependencies($file->info['dependencies']));
      }
    }
  }

  // Filter out enabled modules.
  $enabled = array_filter($install, 'module_exists');
  $install = array_diff($install, $enabled);

  if (!empty($install)) {
    // Make sure the install API is available.
    $install = array_unique($install);
    include_once './includes/install.inc';
    drupal_install_modules($install);
  }
}

/**
 * Wrapper around features_get_info() that returns an array
 * of module info objects that are features.
 */
function features_get_features($name = NULL, $reset = FALSE) {
  return features_get_info('feature', $name, $reset);
}

/**
 * Helper for retrieving info from system table.
 */
function features_get_info($type = 'module', $name = NULL, $reset = FALSE) {
  static $cache;
  if (!isset($cache)) {
    $cache = cache_get('features_module_info');
  }
  if (empty($cache) || $reset) {
    $data = array();
    $ignored = variable_get('features_ignored_orphans', array());
    $result = db_query("SELECT filename, name, type, status, throttle, schema_version FROM {system} WHERE type = 'module' ORDER BY name ASC");
    while ($row = db_fetch_object($result)) {
      // If module is no longer enabled, remove it from the ignored orphans list.
      if (in_array($row->name, $ignored, TRUE) && !$row->status) {
        $key = array_search($row->name, $ignored, TRUE);
        unset($ignored[$key]);
      }

      // Parse and allow modules to alter the info file if necessary.
      $row->info = drupal_parse_info_file(dirname($row->filename) .'/'. $row->name .'.info');
      if (!empty($row->info)) {
        drupal_alter('system_info', $row->info, $row);
        if (!empty($row->info['features'])) {
          $data['feature'][$row->name] = $row;
        }
        $data['module'][$row->name] = $row;
      }
    }
    variable_set('features_ignored_orphans', $ignored);
    cache_set("features_module_info", $data);
    $cache = new stdClass();
    $cache->data = $data;
  }
  if (!empty($name)) {
    return !empty($cache->data[$type][$name]) ? $cache->data[$type][$name] : array();
  }
  return !empty($cache->data[$type]) ? $cache->data[$type] : array();
}

/**
 * Generate an array of feature dependencies that have been orphaned.
 */
function features_get_orphans($reset = FALSE) {
  static $orphans;
  if (!isset($orphans) || $reset) {
    module_load_include('inc', 'features', 'features.export');
    $orphans = array();

    // Build a list of all dependencies for enabled and disabled features.
    $dependencies = array('enabled' => array(), 'disabled' => array());
    $features = features_get_features();
    foreach ($features as $feature) {
      $key = module_exists($feature->name) ? 'enabled' : 'disabled';
      if (!empty($feature->info['dependencies'])) {
        $dependencies[$key] = array_merge($dependencies[$key], _features_export_maximize_dependencies($feature->info['dependencies']));
      }
    }
    $dependencies['enabled'] = array_unique($dependencies['enabled']);
    $dependencies['disabled'] = array_unique($dependencies['disabled']);

    // Find the list of orphaned modules.
    $orphaned = array_diff($dependencies['disabled'], $dependencies['enabled']);
    $orphaned = array_intersect($orphaned, module_list(FALSE, FALSE));
    $orphaned = array_diff($orphaned, drupal_required_modules());
    $orphaned = array_diff($orphaned, array('features'));

    // Build final list of modules that can be disabled.
    $modules = features_get_modules(NULL, TRUE);
    $enabled = module_list();
    _module_build_dependencies($modules);

    foreach ($orphaned as $module) {
      if (!empty($modules[$module]->info['dependents'])) {
        // Determine whether any dependents are actually enabled.
        $dependents = array_intersect($modules[$module]->info['dependents'], $enabled);
        if (empty($dependents)) {
          $info = features_get_modules($module);
          $orphans[$module] = $info;
        }
      }
    }
  }
  return $orphans;
}

/**
 * Detect potential conflicts between any features that provide
 * identical components.
 */
function features_get_conflicts($reset = FALSE) {
  $conflicts = array();
  $component_info = features_get_components();
  $map = features_get_component_map($reset);

  foreach ($map as $type => $components) {
    foreach ($components as $component => $modules) {
      if (isset($component_info[$type]['duplicates']) && $component_info[$type]['duplicates'] == FEATURES_DUPLICATES_ALLOWED) {
        continue;
      }
      else if (count($modules) > 1) {
        foreach ($modules as $module) {
          if (!isset($conflicts[$module])) {
            $conflicts[$module] = array();
          }
          foreach ($modules as $m) {
            if ($m != $module) {
              $conflicts[$module][$m] = $m;
            }
          }
        }
      }
    }
  }

  return $conflicts;
}

/**
 * Provide a component to feature map.
 */
function features_get_component_map($reset = FALSE) {
  static $map;

  if (!isset($map) || $reset) {
    $map = array();
    $features = features_get_features('', TRUE);
    foreach ($features as $feature) {
      foreach ($feature->info['features'] as $type => $components) {
        if (!isset($map[$type])) {
          $map[$type] = array();
        }
        foreach ($components as $component) {
          $map[$type][$component][] = $feature->name;
        }
      }
    }
  }

  return $map;
}

/**
 * Simple wrapper returns the status of a module.
 */
function features_get_module_status($module) {
  if (module_exists($module)) {
    return FEATURES_MODULE_ENABLED;
  }
  else if (features_get_modules($module)) {
    return FEATURES_MODULE_DISABLED;
  }
  else {
    return FEATURES_MODULE_MISSING;
  }
}

/**
 * Menu title callback.
 */
function features_get_feature_title($feature) {
  return $feature->info['name'];
}

/**
 * Menu access callback for whether a user should be able to access
 * override actions for a given feature.
 */
function features_access_override_actions($feature) {
  if (user_access('administer features')) {
    static $access = array();
    if (!isset($access[$feature->name])) {
      // Set a value first. We may get called again from within features_detect_overrides().
      $access[$feature->name] = FALSE;

      features_include();
      module_load_include('inc', 'features', 'features.export');
      $access[$feature->name] = in_array(features_get_storage($feature->name), array(FEATURES_OVERRIDDEN, FEATURES_NEEDS_REVIEW)) && user_access('administer features');
    }
    return $access[$feature->name];
  }
  return FALSE;
}

/**
 * Implementation of hook_form_alter() for system_modules form.
 */
function features_form_system_modules_alter(&$form) {
  features_rebuild();
}

/**
 * Restore the specified modules to the default state.
 */
function _features_restore($op, $items = array()) {
  // Since we can't ensure that users will run update.php immediately after
  // updating the features codebase, we must check the schema version explicitly
  // to ensure that we will not blow away any overrides.
  module_load_install('features');
  if (drupal_get_installed_schema_version('features', TRUE) < 6101) {
    return;
  }

  module_load_include('inc', 'features', 'features.export');
  features_include();

  switch ($op) {
    case 'revert':
      $restore_states = array(FEATURES_OVERRIDDEN, FEATURES_REBUILDABLE, FEATURES_NEEDS_REVIEW);
      $restore_hook = 'features_revert';
      $log_action = 'Revert';
      break;
    case 'rebuild':
      $restore_states = array(FEATURES_REBUILDABLE);
      $restore_hook = 'features_rebuild';
      $log_action = 'Rebuild';
      break;
  }

  if (empty($items)) {
    $states = features_get_component_states();
    foreach ($states as $module_name => $components) {
      foreach ($components as $component => $state) {
        if (in_array($state, $restore_states)) {
          $items[$module_name][] = $component;
        }
      }
    }
  }

  foreach ($items as $module_name => $components) {
    foreach ($components as $component) {
      if (features_hook($component, $restore_hook)) {
        // Set a semaphore to prevent other instances of the same script from running concurrently.
        watchdog('features', '@actioning @module_name / @component.', array('@action' => $log_action, '@component' => $component, '@module_name' => $module_name));
        features_semaphore('set', $component);
        features_invoke($component, $restore_hook, $module_name);

        // If the script completes, remove the semaphore and set the code signature.
        features_semaphore('del', $component);
        features_set_signature($module_name, $component);
        watchdog('features', '@action completed for @module_name / @component.', array('@action' => $log_action, '@component' => $component, '@module_name' => $module_name));
      }
    }
  }
}

/**
 * Wrapper around _features_restore().
 */
function features_revert($revert = array()) {
  return _features_restore('revert', $revert);
}

/**
 * Wrapper around _features_restore().
 */
function features_rebuild($rebuild = array()) {
  return _features_restore('rebuild', $rebuild);
}

/**
 * Utility functions ==================================================
 */
 
/**
 * Represent the current state of permissions as a role name to role/perm array.
 */
function _features_get_roles() {
  $roles = array();
  $result = db_query("SELECT r.rid, r.name, p.perm FROM {role} r LEFT JOIN {permission} p ON r.rid = p.rid");
  while ($row = db_fetch_object($result)) {
    $roles[$row->name] = array(
      'rid' => $row->rid,
      'perm' => explode(', ', $row->perm),
    );
  }
  return $roles;
}