/**
 * Copyright (c) 2014, Vincent Petry <pvince81@owncloud.com>
 * This file is licensed under the Affero General Public License version 3 or later.
 * See the COPYING-README file.
 */
OC.Settings = OC.Settings || {};
OC.Settings = _.extend(OC.Settings, {

	_cachedGroups: null,

	/**
	 * Setup selection box for group selection.
	 *
	 * Values need to be separated by a pipe "|" character.
	 * (mostly because a comma is more likely to be used
	 * for groups)
	 *
	 * @param $elements jQuery element (hidden input) to setup select2 on
	 * @param {Array} [extraOptions] extra options hash to pass to select2
	 * @param {Array} [options] extra options
	 * @param {Array} [options.excludeAdmins=false] flag whether to exclude admin groups
	 */
	setupGroupsSelect: function($elements, extraOptions, options) {
		var self = this;
		options = options || {};
		if ($elements.length > 0) {
			// note: settings are saved through a "change" event registered
			// on all input fields
			$elements.select2(_.extend({
				placeholder: t('core', 'Groups'),
				allowClear: true,
				multiple: true,
				separator: '|',
				query: _.debounce(function(query) {
					var queryData = {};
					if (self._cachedGroups && query.term === '') {
						query.callback({results: self._cachedGroups});
						return;
					}
					if (query.term !== '') {
						queryData = {
							pattern: query.term,
							filterGroups: 1
						};
					}
					$.ajax({
						url: OC.generateUrl('/settings/users/groups'),
						data: queryData,
						dataType: 'json',
						success: function(data) {
							var results = [];

							// add groups
							if (!options.excludeAdmins) {
								$.each(data.data.adminGroups, function(i, group) {
									results.push({id:group.id, displayname:group.name});
								});
							}
							$.each(data.data.groups, function(i, group) {
								results.push({id:group.id, displayname:group.name});
							});

							if (query.term === '') {
								// cache full list
								self._cachedGroups = results;
							}
							query.callback({results: results});
						}
					});
				}, 100, true),
				id: function(element) {
					return element.id;
				},
				initSelection: function(element, callback) {
					var selection =
						_.map(($(element).val() || []).split('|').sort(),
							function(groupName) {
						return {
							id: groupName,
							displayname: groupName
						};
					});
					callback(selection);
				},
				formatResult: function (element) {
					return escapeHTML(element.displayname);
				},
				formatSelection: function (element) {
					return escapeHTML(element.displayname);
				},
				escapeMarkup: function(m) {
					// prevent double markup escape
					return m;
				}
			}, extraOptions || {}));
		}
	}
});
