1 files changed, 125 insertions, 0 deletions
diff --git a/lib/private/legacy/OC_Hook.php b/lib/private/legacy/OC_Hook.php
new file mode 100644
index 00000000000..e472b105498
--- /dev/null
+++ b/lib/private/legacy/OC_Hook.php
@@ -0,0 +1,125 @@
+<?php
+
+/**
+ * SPDX-FileCopyrightText: 2016-2024 Nextcloud GmbH and Nextcloud contributors
+ * SPDX-FileCopyrightText: 2016 ownCloud, Inc.
+ * SPDX-License-Identifier: AGPL-3.0-only
+ */
+
+use Psr\Log\LoggerInterface;
+
+class OC_Hook {
+	public static $thrownExceptions = [];
+
+	private static $registered = [];
+
+	/**
+	 * connects a function to a hook
+	 *
+	 * @param string $signalClass class name of emitter
+	 * @param string $signalName name of signal
+	 * @param string|object $slotClass class name of slot
+	 * @param string $slotName name of slot
+	 * @return bool
+	 *
+	 * This function makes it very easy to connect to use hooks.
+	 *
+	 * TODO: write example
+	 */
+	public static function connect($signalClass, $signalName, $slotClass, $slotName) {
+		// If we're trying to connect to an emitting class that isn't
+		// yet registered, register it
+		if (!array_key_exists($signalClass, self::$registered)) {
+			self::$registered[$signalClass] = [];
+		}
+		// If we're trying to connect to an emitting method that isn't
+		// yet registered, register it with the emitting class
+		if (!array_key_exists($signalName, self::$registered[$signalClass])) {
+			self::$registered[$signalClass][$signalName] = [];
+		}
+
+		// don't connect hooks twice
+		foreach (self::$registered[$signalClass][$signalName] as $hook) {
+			if ($hook['class'] === $slotClass and $hook['name'] === $slotName) {
+				return false;
+			}
+		}
+		// Connect the hook handler to the requested emitter
+		self::$registered[$signalClass][$signalName][] = [
+			'class' => $slotClass,
+			'name' => $slotName
+		];
+
+		// No chance for failure ;-)
+		return true;
+	}
+
+	/**
+	 * emits a signal
+	 *
+	 * @param string $signalClass class name of emitter
+	 * @param string $signalName name of signal
+	 * @param mixed $params default: array() array with additional data
+	 * @return bool true if slots exists or false if not
+	 * @throws \OCP\HintException
+	 * @throws \OC\ServerNotAvailableException Emits a signal. To get data from the slot use references!
+	 *
+	 * TODO: write example
+	 */
+	public static function emit($signalClass, $signalName, $params = []) {
+		// Return false if no hook handlers are listening to this
+		// emitting class
+		if (!array_key_exists($signalClass, self::$registered)) {
+			return false;
+		}
+
+		// Return false if no hook handlers are listening to this
+		// emitting method
+		if (!array_key_exists($signalName, self::$registered[$signalClass])) {
+			return false;
+		}
+
+		// Call all slots
+		foreach (self::$registered[$signalClass][$signalName] as $i) {
+			try {
+				call_user_func([ $i['class'], $i['name'] ], $params);
+			} catch (Exception $e) {
+				self::$thrownExceptions[] = $e;
+				\OCP\Server::get(LoggerInterface::class)->error($e->getMessage(), ['exception' => $e]);
+				if ($e instanceof \OCP\HintException) {
+					throw $e;
+				}
+				if ($e instanceof \OC\ServerNotAvailableException) {
+					throw $e;
+				}
+			}
+		}
+
+		return true;
+	}
+
+	/**
+	 * clear hooks
+	 * @param string $signalClass
+	 * @param string $signalName
+	 */
+	public static function clear($signalClass = '', $signalName = '') {
+		if ($signalClass) {
+			if ($signalName) {
+				self::$registered[$signalClass][$signalName] = [];
+			} else {
+				self::$registered[$signalClass] = [];
+			}
+		} else {
+			self::$registered = [];
+		}
+	}
+
+	/**
+	 * DO NOT USE!
+	 * For unit tests ONLY!
+	 */
+	public static function getHooks() {
+		return self::$registered;
+	}
+}