<?php
/**
 * @file src/Core/Addon.php
 */
namespace Friendica\Core;

use Friendica\BaseObject;
use Friendica\Database\DBA;

/**
 * Some functions to handle addons
 */
class Addon extends BaseObject
{
	/**
	 * List of the names of enabled addons
	 *
	 * @var array
	 */
	private static $addons = [];

	/**
	 * @brief Synchronize addons:
	 *
	 * system.addon contains a comma-separated list of names
	 * of addons which are used on this system.
	 * Go through the database list of already installed addons, and if we have
	 * an entry, but it isn't in the config list, call the uninstall procedure
	 * and mark it uninstalled in the database (for now we'll remove it).
	 * Then go through the config list and if we have a addon that isn't installed,
	 * call the install procedure and add it to the database.
	 *
	 */
	public static function loadAddons()
	{
		$installed_addons = [];

		$r = DBA::select('addon', [], ['installed' => 1]);
		if (DBA::isResult($r)) {
			$installed_addons = DBA::toArray($r);
		}

		$addons = Config::get('system', 'addon');
		$addons_arr = [];

		if ($addons) {
			$addons_arr = explode(',', str_replace(' ', '', $addons));
		}

		self::$addons = $addons_arr;

		$installed_arr = [];

		foreach ($installed_addons as $addon) {
			if (!self::isEnabled($addon['name'])) {
				self::uninstall($addon['name']);
			} else {
				$installed_arr[] = $addon['name'];
			}
		}

		foreach (self::$addons as $p) {
			if (!in_array($p, $installed_arr)) {
				self::install($p);
			}
		}
	}

	/**
	 * @brief uninstalls an addon.
	 *
	 * @param string $addon name of the addon
	 * @return void
	 * @throws \Exception
	 */
	public static function uninstall($addon)
	{
		Logger::notice("Addon {addon}: {action}", ['action' => 'uninstall', 'addon' => $addon]);
		DBA::delete('addon', ['name' => $addon]);

		@include_once('addon/' . $addon . '/' . $addon . '.php');
		if (function_exists($addon . '_uninstall')) {
			$func = $addon . '_uninstall';
			$func();
		}

		unset(self::$addons[array_search($addon, self::$addons)]);
	}

	/**
	 * @brief installs an addon.
	 *
	 * @param string $addon name of the addon
	 * @return bool
	 * @throws \Exception
	 */
	public static function install($addon)
	{
		// silently fail if addon was removed

		if (!file_exists('addon/' . $addon . '/' . $addon . '.php')) {
			return false;
		}
		Logger::notice("Addon {addon}: {action}", ['action' => 'install', 'addon' => $addon]);
		$t = @filemtime('addon/' . $addon . '/' . $addon . '.php');
		@include_once('addon/' . $addon . '/' . $addon . '.php');
		if (function_exists($addon . '_install')) {
			$func = $addon . '_install';
			$func();

			$addon_admin = (function_exists($addon . "_addon_admin") ? 1 : 0);

			DBA::insert('addon', ['name' => $addon, 'installed' => true,
				'timestamp' => $t, 'plugin_admin' => $addon_admin]);

			// we can add the following with the previous SQL
			// once most site tables have been updated.
			// This way the system won't fall over dead during the update.

			if (file_exists('addon/' . $addon . '/.hidden')) {
				DBA::update('addon', ['hidden' => true], ['name' => $addon]);
			}

			if (!self::isEnabled($addon)) {
				self::$addons[] = $addon;
			}
			return true;
		} else {
			Logger::error("Addon {addon}: {action} failed", ['action' => 'uninstall', 'addon' => $addon]);
			return false;
		}
	}

	/**
	 * reload all updated addons
	 */
	public static function reload()
	{
		$addons = Config::get('system', 'addon');
		if (strlen($addons)) {
			$r = DBA::select('addon', [], ['installed' => 1]);
			if (DBA::isResult($r)) {
				$installed = DBA::toArray($r);
			} else {
				$installed = [];
			}

			$addon_list = explode(',', $addons);

			if (count($addon_list)) {
				foreach ($addon_list as $addon) {
					$addon = trim($addon);
					$fname = 'addon/' . $addon . '/' . $addon . '.php';

					if (file_exists($fname)) {
						$t = @filemtime($fname);
						foreach ($installed as $i) {
							if (($i['name'] == $addon) && ($i['timestamp'] != $t)) {

								Logger::notice("Addon {addon}: {action}", ['action' => 'reload', 'addon' => $i['name']]);
								@include_once($fname);

								if (function_exists($addon . '_uninstall')) {
									$func = $addon . '_uninstall';
									$func();
								}
								if (function_exists($addon . '_install')) {
									$func = $addon . '_install';
									$func();
								}
								DBA::update('addon', ['timestamp' => $t], ['id' => $i['id']]);
							}
						}
					}
				}
			}
		}
	}

	/**
	 * @brief Parse addon comment in search of addon infos.
	 *
	 * like
	 * \code
	 *   * Name: addon
	 *   * Description: An addon which plugs in
	 * . * Version: 1.2.3
	 *   * Author: John <profile url>
	 *   * Author: Jane <email>
	 *   * Maintainer: Jess <email>
	 *   *
	 *   *\endcode
	 * @param string $addon the name of the addon
	 * @return array with the addon information
	 * @throws \Exception
	 */
	public static function getInfo($addon)
	{
		$a = self::getApp();

		$info = [
			'name' => $addon,
			'description' => "",
			'author' => [],
			'maintainer' => [],
			'version' => "",
			'status' => ""
		];

		if (!is_file("addon/$addon/$addon.php")) {
			return $info;
		}

		$stamp1 = microtime(true);
		$f = file_get_contents("addon/$addon/$addon.php");
		$a->saveTimestamp($stamp1, "file");

		$r = preg_match("|/\*.*\*/|msU", $f, $m);

		if ($r) {
			$ll = explode("\n", $m[0]);
			foreach ($ll as $l) {
				$l = trim($l, "\t\n\r */");
				if ($l != "") {
					$addon_info = array_map("trim", explode(":", $l, 2));
					if (count($addon_info) < 2) {
						continue;
					}

					list($type, $v) = $addon_info;
					$type = strtolower($type);
					if ($type == "author" || $type == "maintainer") {
						$r = preg_match("|([^<]+)<([^>]+)>|", $v, $m);
						if ($r) {
							$info[$type][] = ['name' => $m[1], 'link' => $m[2]];
						} else {
							$info[$type][] = ['name' => $v];
						}
					} else {
						if (array_key_exists($type, $info)) {
							$info[$type] = $v;
						}
					}
				}
			}
		}
		return $info;
	}

	/**
	 * Checks if the provided addon is enabled
	 *
	 * @param string $addon
	 * @return boolean
	 */
	public static function isEnabled($addon)
	{
		return in_array($addon, self::$addons);
	}

	/**
	 * Returns a list of the enabled addon names
	 *
	 * @return array
	 */
	public static function getEnabledList()
	{
		return self::$addons;
	}

	/**
	 * Saves the current enabled addon list in the system.addon config key
	 *
	 * @return boolean
	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
	 */
	public static function saveEnabledList()
	{
		return Config::set("system", "addon", implode(", ", self::$addons));
	}

	/**
	 * Returns the list of non-hidden enabled addon names
	 *
	 * @return array
	 * @throws \Exception
	 */
	public static function getVisibleList()
	{
		$visible_addons = [];
		$stmt = DBA::select('addon', ['name'], ['hidden' => false, 'installed' => true]);
		if (DBA::isResult($stmt)) {
			foreach (DBA::toArray($stmt) as $addon) {
				$visible_addons[] = $addon['name'];
			}
		}

		return $visible_addons;
	}

	/**
	 * Shim of Hook::register left for backward compatibility purpose.
	 *
	 * @see        Hook::register
	 * @deprecated since version 2018.12
	 * @param string $hook     the name of the hook
	 * @param string $file     the name of the file that hooks into
	 * @param string $function the name of the function that the hook will call
	 * @param int    $priority A priority (defaults to 0)
	 * @return mixed|bool
	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
	 */
	public static function registerHook($hook, $file, $function, $priority = 0)
	{
		return Hook::register($hook, $file, $function, $priority);
	}

	/**
	 * Shim of Hook::unregister left for backward compatibility purpose.
	 *
	 * @see        Hook::unregister
	 * @deprecated since version 2018.12
	 * @param string $hook     the name of the hook
	 * @param string $file     the name of the file that hooks into
	 * @param string $function the name of the function that the hook called
	 * @return boolean
	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
	 */
	public static function unregisterHook($hook, $file, $function)
	{
		return Hook::unregister($hook, $file, $function);
	}

	/**
	 * Shim of Hook::callAll left for backward-compatibility purpose.
	 *
	 * @see        Hook::callAll
	 * @deprecated since version 2018.12
	 * @param string        $name of the hook to call
	 * @param string|array &$data to transmit to the callback handler
	 * @throws \Friendica\Network\HTTPException\InternalServerErrorException
	 */
	public static function callHooks($name, &$data = null)
	{
		Hook::callAll($name, $data);
	}
}
