1 files changed, 103 insertions, 0 deletions
diff --git a/lib/private/hooks/emittertrait.php b/lib/private/hooks/emittertrait.php
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+++ b/lib/private/hooks/emittertrait.php
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+<?php
+/**
+ * @author Morris Jobke <hey@morrisjobke.de>
+ * @author Robin Appelman <icewind@owncloud.com>
+ *
+ * @copyright Copyright (c) 2015, ownCloud, Inc.
+ * @license AGPL-3.0
+ *
+ * This code is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License, version 3,
+ * as published by the Free Software Foundation.
+ *
+ * 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, version 3,
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>
+ *
+ */
+
+namespace OC\Hooks;
+
+trait EmitterTrait {
+
+	/**
+	 * @var (callable[])[] $listeners
+	 */
+	protected $listeners = array();
+
+	/**
+	 * @param string $scope
+	 * @param string $method
+	 * @param callable $callback
+	 */
+	public function listen($scope, $method, $callback) {
+		$eventName = $scope . '::' . $method;
+		if (!isset($this->listeners[$eventName])) {
+			$this->listeners[$eventName] = array();
+		}
+		if (array_search($callback, $this->listeners[$eventName]) === false) {
+			$this->listeners[$eventName][] = $callback;
+		}
+	}
+
+	/**
+	 * @param string $scope optional
+	 * @param string $method optional
+	 * @param callable $callback optional
+	 */
+	public function removeListener($scope = null, $method = null, $callback = null) {
+		$names = array();
+		$allNames = array_keys($this->listeners);
+		if ($scope and $method) {
+			$name = $scope . '::' . $method;
+			if (isset($this->listeners[$name])) {
+				$names[] = $name;
+			}
+		} elseif ($scope) {
+			foreach ($allNames as $name) {
+				$parts = explode('::', $name, 2);
+				if ($parts[0] == $scope) {
+					$names[] = $name;
+				}
+			}
+		} elseif ($method) {
+			foreach ($allNames as $name) {
+				$parts = explode('::', $name, 2);
+				if ($parts[1] == $method) {
+					$names[] = $name;
+				}
+			}
+		} else {
+			$names = $allNames;
+		}
+
+		foreach ($names as $name) {
+			if ($callback) {
+				$index = array_search($callback, $this->listeners[$name]);
+				if ($index !== false) {
+					unset($this->listeners[$name][$index]);
+				}
+			} else {
+				$this->listeners[$name] = array();
+			}
+		}
+	}
+
+	/**
+	 * @param string $scope
+	 * @param string $method
+	 * @param array $arguments optional
+	 */
+	protected function emit($scope, $method, $arguments = array()) {
+		$eventName = $scope . '::' . $method;
+		if (isset($this->listeners[$eventName])) {
+			foreach ($this->listeners[$eventName] as $callback) {
+				call_user_func_array($callback, $arguments);
+			}
+		}
+	}
+}