<?php
/**
 * @file src/Core/Addon.php
 */
namespace Friendica\Core;

use Friendica\App;
use Friendica\Core\Config;
use Friendica\Core\System;
use Friendica\Database\DBM;

/**
 * Some functions to handle addons
 */
class Addon
{
    /**
     * @brief uninstalls an addon.
     *
     * @param string $plugin name of the addon
     * @return boolean
     */
    function uninstall_plugin($plugin) {
        logger("Addons: uninstalling " . $plugin);
        dba::delete('addon', ['name' => $plugin]);

        @include_once('addon/' . $plugin . '/' . $plugin . '.php');
        if (function_exists($plugin . '_uninstall')) {
            $func = $plugin . '_uninstall';
            $func();
        }
    }

    /**
     * @brief installs an addon.
     *
     * @param string $plugin name of the addon
     * @return bool
     */
    function install_plugin($plugin) {
        // silently fail if plugin was removed

        if (!file_exists('addon/' . $plugin . '/' . $plugin . '.php')) {
            return false;
        }
        logger("Addons: installing " . $plugin);
        $t = @filemtime('addon/' . $plugin . '/' . $plugin . '.php');
        @include_once('addon/' . $plugin . '/' . $plugin . '.php');
        if (function_exists($plugin . '_install')) {
            $func = $plugin . '_install';
            $func();

            $plugin_admin = (function_exists($plugin."_plugin_admin") ? 1 : 0);

            dba::insert('addon', ['name' => $plugin, 'installed' => true,
                        'timestamp' => $t, 'plugin_admin' => $plugin_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/' . $plugin . '/.hidden')) {
                dba::update('addon', ['hidden' => true], ['name' => $plugin]);
            }
            return true;
        } else {
            logger("Addons: FAILED installing " . $plugin);
            return false;
        }
    }

    // reload all updated plugins

    function reload_plugins() {
        $plugins = Config::get('system', 'addon');
        if (strlen($plugins)) {

            $r = q("SELECT * FROM `addon` WHERE `installed` = 1");
            if (DBM::is_result($r)) {
                $installed = $r;
            } else {
                $installed = [];
            }

            $parr = explode(',',$plugins);

            if (count($parr)) {
                foreach ($parr as $pl) {

                    $pl = trim($pl);

                    $fname = 'addon/' . $pl . '/' . $pl . '.php';

                    if (file_exists($fname)) {
                        $t = @filemtime($fname);
                        foreach ($installed as $i) {
                            if (($i['name'] == $pl) && ($i['timestamp'] != $t)) {
                                logger('Reloading plugin: ' . $i['name']);
                                @include_once($fname);

                                if (function_exists($pl . '_uninstall')) {
                                    $func = $pl . '_uninstall';
                                    $func();
                                }
                                if (function_exists($pl . '_install')) {
                                    $func = $pl . '_install';
                                    $func();
                                }
                                dba::update('addon', ['timestamp' => $t], ['id' => $i['id']]);
                            }
                        }
                    }
                }
            }
        }

    }

    /**
     * @brief check if addon is enabled
     *
     * @param string $plugin
     * @return boolean
     */
    function plugin_enabled($plugin) {
        return dba::exists('addon', ['installed' => true, 'name' => $plugin]);
    }


    /**
     * @brief registers a hook.
     *
     * @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 $priority A priority (defaults to 0)
     * @return mixed|bool
     */
    function register_hook($hook, $file, $function, $priority=0) {
        $condition = ['hook' => $hook, 'file' => $file, 'function' => $function];
        $exists = dba::exists('hook', $condition);
        if ($exists) {
            return true;
        }

        $r = dba::insert('hook', ['hook' => $hook, 'file' => $file, 'function' => $function, 'priority' => $priority]);

        return $r;
    }

    /**
     * @brief unregisters a hook.
     *
     * @param string $hook the name of the hook
     * @param string $file the name of the file that hooks into
     * @param string $function the name of the function that the hook called
     * @return array
     */
    function unregister_hook($hook, $file, $function) {
        $condition = ['hook' => $hook, 'file' => $file, 'function' => $function];
        $r = dba::delete('hook', $condition);
        return $r;
    }


    function load_hooks() {
        $a = get_app();
        $a->hooks = [];
        $r = dba::select('hook', ['hook', 'file', 'function'], [], ['order' => ['priority' => 'desc', 'file']]);

        while ($rr = dba::fetch($r)) {
            if (! array_key_exists($rr['hook'],$a->hooks)) {
                $a->hooks[$rr['hook']] = [];
            }
            $a->hooks[$rr['hook']][] = [$rr['file'],$rr['function']];
        }
        dba::close($r);
    }

    /**
     * @brief Calls a hook.
     *
     * Use this function when you want to be able to allow a hook to manipulate
     * the provided data.
     *
     * @param string $name of the hook to call
     * @param string|array &$data to transmit to the callback handler
     */
    function call_hooks($name, &$data = null)
    {
        $a = get_app();

        if (is_array($a->hooks) && array_key_exists($name, $a->hooks)) {
            foreach ($a->hooks[$name] as $hook) {
                call_single_hook($a, $name, $hook, $data);
            }
        }
    }

    /**
     * @brief Calls a single hook.
     *
     * @param string $name of the hook to call
     * @param array $hook Hook data
     * @param string|array &$data to transmit to the callback handler
     */
    function call_single_hook($a, $name, $hook, &$data = null) {
        // Don't run a theme's hook if the user isn't using the theme
        if (strpos($hook[0], 'view/theme/') !== false && strpos($hook[0], 'view/theme/'.current_theme()) === false)
            return;

        @include_once($hook[0]);
        if (function_exists($hook[1])) {
            $func = $hook[1];
            $func($a, $data);
        } else {
            // remove orphan hooks
            $condition = ['hook' => $name, 'file' => $hook[0], 'function' => $hook[1]];
            dba::delete('hook', $condition);
        }
    }

    //check if an app_menu hook exist for plugin $name.
    //Return true if the plugin is an app
    function plugin_is_app($name) {
        $a = get_app();

        if (is_array($a->hooks) && (array_key_exists('app_menu',$a->hooks))) {
            foreach ($a->hooks['app_menu'] as $hook) {
                if ($hook[0] == 'addon/'.$name.'/'.$name.'.php')
                    return true;
            }
        }

        return false;
    }

    /**
     * @brief Parse plugin comment in search of plugin infos.
     *
     * like
     * \code
     *...* Name: Plugin
    *   * Description: A plugin which plugs in
    * . * Version: 1.2.3
    *   * Author: John <profile url>
    *   * Author: Jane <email>
    *   *
    *  *\endcode
    * @param string $plugin the name of the plugin
    * @return array with the plugin information
    */

    function get_plugin_info($plugin) {

        $a = get_app();

        $info=[
            'name' => $plugin,
            'description' => "",
            'author' => [],
            'version' => "",
            'status' => ""
        ];

        if (!is_file("addon/$plugin/$plugin.php")) return $info;

        $stamp1 = microtime(true);
        $f = file_get_contents("addon/$plugin/$plugin.php");
        $a->save_timestamp($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 ($l != "") {
                    list($k,$v) = array_map("trim", explode(":",$l,2));
                    $k= strtolower($k);
                    if ($k == "author") {
                        $r=preg_match("|([^<]+)<([^>]+)>|", $v, $m);
                        if ($r) {
                            $info['author'][] = ['name'=>$m[1], 'link'=>$m[2]];
                        } else {
                            $info['author'][] = ['name'=>$v];
                        }
                    } else {
                        if (array_key_exists($k,$info)) {
                            $info[$k]=$v;
                        }
                    }

                }
            }

        }
        return $info;
    }
}