<?php

/**
 * ActiveSync configuration utility for Kolab accounts
 *
 * @version @package_version@
 * @author Aleksander Machniak <machniak@kolabsys.com>
 * @author Thomas Bruederli <bruederli@kolabsys.com>
 *
 * Copyright (C) 2011-2012, Kolab Systems AG <contact@kolabsys.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * 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
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 */

class kolab_activesync extends rcube_plugin
{
    public $task = 'settings';
    public $urlbase;
    public $backend;

    private $rc;
    private $ui;
    private $folder_meta;
    private $root_meta;

    const ROOT_MAILBOX = 'INBOX';
    const ASYNC_KEY    = '/private/vendor/kolab/activesync';
    const CTYPE_KEY    = '/shared/vendor/kolab/folder-type';


    /**
     * Plugin initialization.
     */
    public function init()
    {
        $this->rc = rcmail::get_instance();

        $this->require_plugin('jqueryui');
        $this->require_plugin('libkolab');

        $this->register_action('plugin.activesyncconfig', array($this, 'config_view'));
        $this->register_action('plugin.activesyncjson', array($this, 'json_command'));

        $this->add_texts('localization/', true);
        $this->include_script('kolab_activesync.js');
    }

    /**
     * Handle JSON requests
     */
    public function json_command()
    {
        $cmd  = get_input_value('cmd', RCUBE_INPUT_GPC);
        $imei = get_input_value('id', RCUBE_INPUT_GPC);

        switch ($cmd) {
        case 'load':
            $devices = $this->list_devices();

            if ($device = $devices[$imei]) {
                $result['id'] = $imei;
                $result['devicealias'] = $device['ALIAS'];
//                $result['syncmode'] = intval($device['MODE']);
//                $result['laxpic'] = intval($device['LAXPIC']);
                $result['subscribed'] = array();

                foreach ($this->folder_meta() as $folder => $meta) {
                    if ($meta['FOLDER'][$imei]['S']) {
                        $result['subscribed'][$folder] = intval($meta['FOLDER'][$imei]['S']);
                    }
                }

                $this->rc->output->command('plugin.activesync_data_ready', $result);
            }
            else {
                $this->rc->output->show_message($this->gettext('devicenotfound'), 'error');
            }
            break;

        case 'save':
            $devices      = $this->list_devices();
            $device       = $devices[$imei];

            $subscriptions = (array) get_input_value('subscribed', RCUBE_INPUT_POST);
            $devicealias   = get_input_value('devicealias', RCUBE_INPUT_POST, true);
//            $syncmode     = intval(get_input_value('syncmode', RCUBE_INPUT_POST));
//            $laxpic       = intval(get_input_value('laxpic', RCUBE_INPUT_POST));
            $device['ALIAS'] = $devicealias;
//            $device['MODE'] = $syncmode;
//            $device['LAXPIC'] = $laxpic;

            $err = !$this->device_update($device, $imei);

            if (!$err) {
                // iterate over folders list and update metadata if necessary
                // old subscriptions
                foreach ($this->folder_meta() as $folder => $meta) {
                    $err |= !$this->folder_set($folder, $imei, intval($subscriptions[$folder]));
                    unset($subsciptions[$folder]);
                }
                // new subscription
                foreach ($subscriptions as $folder => $flag) {
                    $err |= !$this->folder_set($folder, $imei, intval($flag));
                }

                $this->rc->output->command('plugin.activesync_save_complete', array(
                    'success' => !$err, 'id' => $imei, 'devicealias' => Q($devicealias)));
            }

            if ($err)
                $this->rc->output->show_message($this->gettext('savingerror'), 'error');
            else
                $this->rc->output->show_message($this->gettext('successfullysaved'), 'confirmation');

            break;

        case 'delete':
            $success = $this->device_delete($imei);

            if ($success) {
                $this->rc->output->show_message($this->gettext('successfullydeleted'), 'confirmation');
                $this->rc->output->redirect(array('action' => 'plugin.activesyncconfig'));  // reload UI
            }
            else
                $this->rc->output->show_message($this->gettext('savingerror'), 'error');

            break;
        }

        $this->rc->output->send();
    }

    /**
     * Render main UI for device configuration
     */
    public function config_view()
    {
        $storage = $this->rc->get_storage();

        // checks if IMAP server supports any of METADATA, ANNOTATEMORE, ANNOTATEMORE2
        if (!($storage->get_capability('METADATA') || $storage->get_capability('ANNOTATEMORE') || $storage->get_capability('ANNOTATEMORE2'))) {
            $this->rc->output->show_message($this->gettext('notsupported'), 'error');
        }

        require_once $this->home . '/kolab_activesync_ui.php';

        $this->ui = new kolab_activesync_ui($this);

        $this->register_handler('plugin.devicelist', array($this->ui, 'device_list'));
        $this->register_handler('plugin.deviceconfigform', array($this->ui, 'device_config_form'));
        $this->register_handler('plugin.foldersubscriptions', array($this->ui, 'folder_subscriptions'));

        $this->rc->output->send('kolab_activesync.config');
    }

    /**
     * Get list of all folders available for sync
     *
     * @return array List of mailbox folders
     */
    public function list_folders()
    {
        $storage = $this->rc->get_storage();

        return $storage->list_folders();
    }

    /**
     * Returns list of folders with assigned type
     *
     * @return array List of folder types indexed by folder name
     */
    public function list_types()
    {
        if ($this->folder_types === null) {
            $storage    = $this->rc->get_storage();
            $folderdata = $storage->get_metadata('*', self::CTYPE_KEY);

            $this->folder_types = array();

            foreach ($folderdata as $folder => $data) {
                if ($data[self::CTYPE_KEY]) {
                    $this->folder_types[$folder] = $data[self::CTYPE_KEY];
                }
            }
        }

        return $this->folder_types;
    }

    /**
     * List known devices
     *
     * @return array Device list as hash array
     */
    public function list_devices()
    {
        if ($this->root_meta === null) {
            $storage = $this->rc->get_storage();
            // @TODO: consider server annotation instead of INBOX
            if ($meta = $storage->get_metadata(self::ROOT_MAILBOX, self::ASYNC_KEY)) {
                $this->root_meta = $this->unserialize_metadata($meta[self::ROOT_MAILBOX][self::ASYNC_KEY]);
            }
            else {
                $this->root_meta = array();
            }
        }

        if (!empty($this->root_meta['DEVICE']) && is_array($this->root_meta['DEVICE'])) {
            return $this->root_meta['DEVICE'];
        }

        return array();
    }

    /**
     * Getter for folder metadata
     *
     * @return array Hash array with meta data for each folder
     */
    public function folder_meta()
    {
        if (!isset($this->folder_meta)) {
            $this->folder_meta = array();
            $storage = $this->rc->get_storage();

            // get folders activesync config
            $folderdata = $storage->get_metadata("*", self::ASYNC_KEY);

            foreach ($folderdata as $folder => $meta) {
                if ($asyncdata = $meta[self::ASYNC_KEY]) {
                    if ($metadata = $this->unserialize_metadata($asyncdata)) {
                        $this->folder_meta[$folder] = $metadata;
                    }
                }
            }
        }

        return $this->folder_meta;
    }

    /**
     * Sets ActiveSync subscription flag on a folder
     *
     * @param string $name      Folder name (UTF7-IMAP)
     * @param string $deviceid  Device identifier
     * @param int    $flag      Flag value (0|1|2)
     */
    public function folder_set($name, $deviceid, $flag)
    {
        // get folders activesync config
        $metadata = $this->folder_meta();
        $metadata = $metadata[$name];

        if ($flag)  {
            if (empty($metadata)) {
                $metadata = array();
            }

            if (empty($metadata['FOLDER'])) {
                $metadata['FOLDER'] = array();
            }

            if (empty($metadata['FOLDER'][$deviceid])) {
                $metadata['FOLDER'][$deviceid] = array();
            }

            // Z-Push uses:
            //  1 - synchronize, no alarms
            //  2 - synchronize with alarms
            $metadata['FOLDER'][$deviceid]['S'] = $flag;
        }

        if (!$flag) {
            unset($metadata['FOLDER'][$deviceid]['S']);

            if (empty($metadata['FOLDER'][$deviceid])) {
                unset($metadata['FOLDER'][$deviceid]);
            }

            if (empty($metadata['FOLDER'])) {
                unset($metadata['FOLDER']);
            }

            if (empty($metadata)) {
                $metadata = null;
            }
        }

        // Return if nothing's been changed
        if (!self::data_array_diff($this->folder_meta[$name], $metadata)) {
            return true;
        }

        $this->folder_meta[$name] = $metadata;

        $storage = $this->rc->get_storage();

        return $storage->set_metadata($name, array(
            self::ASYNC_KEY => $this->serialize_metadata($metadata)));
    }


    public function device_update($device, $id)
    {
        $devices_list = $this->list_devices();
        $old_device   = $devices_list[$id];

        if (!$old_device) {
            return false;
        }

        // Do nothing if nothing is changed
        if (!self::data_array_diff($old_device, $device)) {
            return true;
        }

        $device = array_merge($old_device, $device);

        $metadata = $this->root_meta;
        $metadata['DEVICE'][$id] = $device;
        $metadata = array(self::ASYNC_KEY => $this->serialize_metadata($metadata));
        $storage  = $this->rc->get_storage();

        $result = $storage->set_metadata(self::ROOT_MAILBOX, $metadata);

        if ($result) {
            // Update local cache
            $this->root_meta['DEVICE'][$id] = $device;
        }

        return $result;
    }


    /**
     * Device delete.
     *
     * @param string $id  Device ID
     *
     * @return bool True on success, False on failure
     */
    public function device_delete($id)
    {
        $devices_list = $this->list_devices();
        $old_device   = $devices_list[$id];

        if (!$old_device) {
            return false;
        }

        unset($this->root_meta['DEVICE'][$id], $this->root_meta['FOLDER'][$id]);

        if (empty($this->root_meta['DEVICE'])) {
            unset($this->root_meta['DEVICE']);
        }
        if (empty($this->root_meta['FOLDER'])) {
            unset($this->root_meta['FOLDER']);
        }

        $metadata = $this->serialize_metadata($this->root_meta);
        $metadata = array(self::ASYNC_KEY => $metadata);
        $storage  = $this->rc->get_storage();

        // update meta data
        $result = $storage->set_metadata(self::ROOT_MAILBOX, $metadata);

        if ($result) {
            // remove device annotation for every folder
            foreach ($this->folder_meta() as $folder => $meta) {
                // skip root folder (already handled above)
                if ($folder == self::ROOT_MAILBOX)
                    continue;

                if (!empty($meta['FOLDER']) && isset($meta['FOLDER'][$id])) {
                    unset($meta['FOLDER'][$id]);

                    if (empty($meta['FOLDER'])) {
                        unset($this->folder_meta[$folder]['FOLDER']);
                        unset($meta['FOLDER']);
                    }
                    if (empty($meta)) {
                        unset($this->folder_meta[$folder]);
                        $meta = null;
                    }

                    $metadata = array(self::ASYNC_KEY => $this->serialize_metadata($meta));
                    $res = $storage->set_metadata($folder, $metadata);

                    if ($res && $meta) {
                        $this->folder_meta[$folder] = $meta;
                    }
                }
            }
        }

        return $result;
    }


    /**
     * Helper method to decode saved IMAP metadata
     */
    private function unserialize_metadata($str)
    {
        if (!empty($str)) {
            $data = json_decode($str, true);
            return $data;
        }

        return null;
    }

    /**
     * Helper method to encode IMAP metadata for saving
     */
    private function serialize_metadata($data)
    {
        if (!empty($data) && is_array($data)) {
            $data = json_encode($data);
            return $data;
        }

        return null;
    }

    /**
     * Compares two arrays
     *
     * @param array $array1
     * @param array $array2
     *
     * @return bool True if arrays differs, False otherwise
     */
    private static function data_array_diff($array1, $array2)
    {
        if (!is_array($array1) || !is_array($array2)) {
            return $array1 != $array2;
        }

        if (count($array1) != count($array2)) {
            return true;
        }

        foreach ($array1 as $key => $val) {
            if (!array_key_exists($key, $array2)) {
                return true;
            }
            if ($val !== $array2[$key]) {
                return true;
            }
        }

        return false;
    }
}