Load the timezones via select2

apps/workflowengine/appinfo/routes.php

@@ -25,5 +25,6 @@ return [
 		['name' => 'flowOperations#addOperation', 'url' => '/operations', 'verb' => 'POST'],
 		['name' => 'flowOperations#updateOperation', 'url' => '/operations/{id}', 'verb' => 'PUT'],
 		['name' => 'flowOperations#deleteOperation', 'url' => '/operations/{id}', 'verb' => 'DELETE'],
+		['name' => 'requestTime#getTimezones', 'url' => '/timezones', 'verb' => 'GET'],
 	]
 ];

apps/workflowengine/lib/AppInfo/Application.php

@@ -30,6 +30,7 @@ class Application extends \OCP\AppFramework\App {
 		parent::__construct('workflowengine');
 
 		$this->getContainer()->registerAlias('FlowOperationsController', 'OCA\WorkflowEngine\Controller\FlowOperations');
+		$this->getContainer()->registerAlias('RequestTimeController', 'OCA\WorkflowEngine\Controller\RequestTime');
 	}
 
 	/**
@@ -51,6 +52,8 @@ class Application extends \OCP\AppFramework\App {
 					'systemtags/systemtagscollection',
 				]);
 
+				vendor_script('jsTimezoneDetect/jstz');
+
 				script('workflowengine', [
 					'admin',
 

apps/workflowengine/lib/Check/RequestTime.php

@@ -29,7 +29,7 @@ use OCP\WorkflowEngine\ICheck;
 class RequestTime implements ICheck {
 
 	const REGEX_TIME = '([0-1][0-9]|2[0-3]):([0-5][0-9])';
-	const REGEX_TIMEZONE = '([a-zA-Z]+(?:\\\\\\/[a-zA-Z\-\_]+)+)';
+	const REGEX_TIMEZONE = '([a-zA-Z]+(?:\\/[a-zA-Z\-\_]+)+)';
 
 	/** @var bool[] */
 	protected $cachedResults;
@@ -110,16 +110,15 @@ class RequestTime implements ICheck {
 			throw new \UnexpectedValueException('Invalid time limits', 2);
 		}
 
-		try {
-			new \DateTimeZone(stripslashes($matches[3]));
-		} catch(\Exception $e) {
-			throw new \UnexpectedValueException('Invalid timezone1', 3);
+		$values = json_decode($value, true);
+		$time1 = \DateTime::createFromFormat('H:i e', $values[0]);
+		if ($time1 === false) {
+			throw new \UnexpectedValueException('Invalid start time given', 3);
 		}
 
-		try {
-			new \DateTimeZone(stripslashes($matches[6]));
-		} catch(\Exception $e) {
-			throw new \UnexpectedValueException('Invalid timezone2', 3);
+		$time2 = \DateTime::createFromFormat('H:i e', $values[1]);
+		if ($time2 === false) {
+			throw new \UnexpectedValueException('Invalid end time given', 3);
 		}
 	}
 }

apps/workflowengine/lib/Controller/RequestTime.php

@@ -0,0 +1,53 @@
+<?php
+/**
+ * @copyright Copyright (c) 2016 Joas Schilling <coding@schilljs.com>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCA\WorkflowEngine\Controller;
+
+use OCP\AppFramework\Controller;
+use OCP\AppFramework\Http\JSONResponse;
+
+class RequestTime extends Controller {
+
+	/**
+	 * @NoCSRFRequired
+	 * @NoAdminRequired
+	 *
+	 * @param string $search
+	 * @return JSONResponse
+	 */
+	public function getTimezones($search = '') {
+		$timezones = \DateTimeZone::listIdentifiers();
+
+		if ($search !== '') {
+			$timezones = array_filter($timezones, function ($timezone) use ($search) {
+				return strpos(strtolower($timezone), strtolower($search)) !== false;
+			});
+		}
+
+		$timezones = array_slice($timezones, 0, 10);
+
+		$response = [];
+		foreach ($timezones as $timezone) {
+			$response[$timezone] = $timezone;
+		}
+		return new JSONResponse($response);
+	}
+}