1 files changed, 89 insertions, 0 deletions
diff --git a/lib/private/hooks/basicemitter.php b/lib/private/hooks/basicemitter.php
new file mode 100644
index 00000000000..9ffe1af2314
--- /dev/null
+++ b/lib/private/hooks/basicemitter.php
@@ -0,0 +1,89 @@
+<?php
+/**
+ * Copyright (c) 2013 Robin Appelman <icewind@owncloud.com>
+ * This file is licensed under the Affero General Public License version 3 or
+ * later.
+ * See the COPYING-README file.
+ */
+
+namespace OC\Hooks;
+
+abstract class BasicEmitter implements Emitter {
+
+	/**
+	 * @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);
+			}
+		}
+	}
+}