<?php
/*
 * StatusNet - the distributed open-source microblogging tool
 * Copyright (C) 2008, 2009, StatusNet, Inc.
 *
 * 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/>.
 */

if (!defined('STATUSNET')) {
    exit(1);
}

require_once INSTALLDIR . '/plugins/Facebook/facebook/facebook.php';
require_once INSTALLDIR . '/plugins/Facebook/facebookaction.php';
require_once INSTALLDIR . '/lib/noticelist.php';

define("FACEBOOK_SERVICE", 2); // Facebook is foreign_service ID 2
define("FACEBOOK_NOTICE_PREFIX", 1);
define("FACEBOOK_PROMPTED_UPDATE_PREF", 2);

function getFacebook()
{
    static $facebook = null;

    $apikey = common_config('facebook', 'apikey');
    $secret = common_config('facebook', 'secret');

    if ($facebook === null) {
        $facebook = new Facebook($apikey, $secret);
    }

    if (empty($facebook)) {
        common_log(LOG_ERR, 'Could not make new Facebook client obj!',
            __FILE__);
    }

    return $facebook;
}

function isFacebookBound($notice, $flink) {
    if (empty($flink)) {
        return false;
    }

    // Avoid a loop
    if ($notice->source == 'Facebook') {
        common_log(LOG_INFO, "Skipping notice $notice->id because its " .
                   'source is Facebook.');
        return false;
    }

    // If the user does not want to broadcast to Facebook, move along
    if (!($flink->noticesync & FOREIGN_NOTICE_SEND == FOREIGN_NOTICE_SEND)) {
        common_log(LOG_INFO, "Skipping notice $notice->id " .
            'because user has FOREIGN_NOTICE_SEND bit off.');
        return false;
    }

    // If it's not a reply, or if the user WANTS to send @-replies,
    // then, yeah, it can go to Facebook.
    if (!preg_match('/@[a-zA-Z0-9_]{1,15}\b/u', $notice->content) ||
        ($flink->noticesync & FOREIGN_NOTICE_SEND_REPLY)) {
        return true;
    }

    return false;
}

function facebookBroadcastNotice($notice)
{
    $facebook = getFacebook();
    $flink = Foreign_link::getByUserID(
        $notice->profile_id,
        FACEBOOK_SERVICE
    );

    if (isFacebookBound($notice, $flink)) {
        // Okay, we're good to go, update the FB status
        $fbuid = $flink->foreign_id;
        $user = $flink->getUser();

        try {
            // Check permissions
            common_debug(
                'FacebookPlugin - checking for publish_stream permission for user '
                . "$user->nickname ($user->id), Facebook UID: $fbuid"
            );

            // NOTE: $facebook->api_client->users_hasAppPermission('publish_stream', $fbuid)
            // has been returning bogus results, so we're using FQL to check for
            // publish_stream permission now
            $fql = "SELECT publish_stream FROM permissions WHERE uid = $fbuid";
            $result = $facebook->api_client->fql_query($fql);

            $canPublish = 0;

            if (!empty($result)) {
                $canPublish = $result[0]['publish_stream'];
            }

            if ($canPublish == 1) {
                common_debug(
                    "FacebookPlugin - $user->nickname ($user->id), Facebook UID: $fbuid "
                    . 'has publish_stream permission.'
                );
            } else {
                common_debug(
                    "FacebookPlugin - $user->nickname ($user->id), Facebook UID: $fbuid "
                    . 'does NOT have publish_stream permission. Facebook '
                    . 'returned: ' . var_export($result, true)
                );
            }

            common_debug(
                'FacebookPlugin - checking for status_update permission for user '
                . "$user->nickname ($user->id), Facebook UID: $fbuid. "
            );

            $canUpdate = $facebook->api_client->users_hasAppPermission(
                'status_update',
                $fbuid
            );

            if ($canUpdate == 1) {
                common_debug(
                    "FacebookPlugin - $user->nickname ($user->id), Facebook UID: $fbuid "
                    . 'has status_update permission.'
                );
            } else {
                common_debug(
                    "FacebookPlugin - $user->nickname ($user->id), Facebook UID: $fbuid "
                    .'does NOT have status_update permission. Facebook '
                    . 'returned: ' . var_export($canPublish, true)
                );
            }

            // Post to Facebook
            if ($notice->hasAttachments() && $canPublish == 1) {
                publishStream($notice, $user, $fbuid);
            } elseif ($canUpdate == 1 || $canPublish == 1) {
                statusUpdate($notice, $user, $fbuid);
            } else {
                $msg = "FacebookPlugin - Not sending notice $notice->id to Facebook " .
                  "because user $user->nickname has not given the " .
                  'Facebook app \'status_update\' or \'publish_stream\' permission.';
                common_log(LOG_WARNING, $msg);
            }

            // Finally, attempt to update the user's profile box
            if ($canPublish == 1 || $canUpdate == 1) {
                updateProfileBox($facebook, $flink, $notice, $user);
            }

        } catch (FacebookRestClientException $e) {
            return handleFacebookError($e, $notice, $flink);
        }
    }

    return true;
}

function handleFacebookError($e, $notice, $flink)
{
    $fbuid  = $flink->foreign_id;
    $user   = $flink->getUser();
    $code   = $e->getCode();
    $errmsg = $e->getMessage();

    // XXX: Check for any others?
    switch($code) {
     case 100: // Invalid parameter
        $msg = "FacebookPlugin - Facebook claims notice %d was posted with an invalid parameter (error code 100):"
            . "\"%s\" (Notice details: nickname=%s, user ID=%d, Facebook ID=%d, notice content=\"%s\"). "
            . "Removing notice from the Facebook queue for safety.";
        common_log(
            LOG_ERR, sprintf(
                $msg,
                $notice->id,
                $errmsg,
                $user->nickname,
                $user->id,
                $fbuid,
                $notice->content
            )
        );
        return true;
        break;
     case 200: // Permissions error
     case 250: // Updating status requires the extended permission status_update
        remove_facebook_app($flink);
        return true; // dequeue
        break;
     case 341: // Feed action request limit reached
            $msg = "FacebookPlugin - User %s (User ID=%d, Facebook ID=%d) has exceeded "
                   . "his/her limit for posting notices to Facebook today. Dequeuing "
                   . "notice %d.";
            common_log(
                LOG_INFO, sprintf(
                    $msg,
                    $user->nickname,
                    $user->id,
                    $fbuid,
                    $notice->id
                )
            );
	// @fixme: We want to rety at a later time when the throttling has expired
	// instead of just giving up.
        return true;
        break;
     default:
        $msg = "FacebookPlugin - Facebook returned an error we don't know how to deal with while trying to "
            . "post notice %d. Error code: %d, error message: \"%s\". (Notice details: "
            . "nickname=%s, user ID=%d, Facebook ID=%d, notice content=\"%s\"). Removing notice "
	    . "from the Facebook queue for safety.";
        common_log(
            LOG_ERR, sprintf(
                $msg,
                $notice->id,
                $code,
                $errmsg,
                $user->nickname,
                $user->id,
                $fbuid,
                $notice->content
            )
        );
        return true; // dequeue
        break;
    }
}

function statusUpdate($notice, $user, $fbuid)
{
    common_debug(
        "FacebookPlugin - Attempting to post notice $notice->id "
        . "as a status update for $user->nickname ($user->id), "
        . "Facebook UID: $fbuid"
    );

    $facebook = getFacebook();
    $result = $facebook->api_client->users_setStatus(
         $notice->content,
         $fbuid,
         false,
         true
    );

    common_debug('Facebook returned: ' . var_export($result, true));

    common_log(
        LOG_INFO,
        "FacebookPlugin - Posted notice $notice->id as a status "
        . "update for $user->nickname ($user->id), "
        . "Facebook UID: $fbuid"
    );
}

function publishStream($notice, $user, $fbuid)
{
    common_debug(
        "FacebookPlugin - Attempting to post notice $notice->id "
        . "as stream item with attachment for $user->nickname ($user->id), "
        . "Facebook UID: $fbuid"
    );

    $fbattachment = format_attachments($notice->attachments());

    $facebook = getFacebook();
    $facebook->api_client->stream_publish(
        $notice->content,
        $fbattachment,
        null,
        null,
        $fbuid
    );

    common_log(
        LOG_INFO,
        "FacebookPlugin - Posted notice $notice->id as a stream "
        . "item with attachment for $user->nickname ($user->id), "
        . "Facebook UID: $fbuid"
    );
}

function updateProfileBox($facebook, $flink, $notice, $user) {

    $facebook = getFacebook();
    $fbaction = new FacebookAction(
        $output = 'php://output',
        $indent = null,
        $facebook,
        $flink
    );

    $fbuid = $flink->foreign_id;

    common_debug(
          'FacebookPlugin - Attempting to update profile box with '
          . "content from notice $notice->id for $user->nickname ($user->id), "
          . "Facebook UID: $fbuid"
    );

    $fbaction->updateProfileBox($notice);

    common_debug(
        'FacebookPlugin - finished updating profile box for '
        . "$user->nickname ($user->id) Facebook UID: $fbuid"
    );

}

function format_attachments($attachments)
{
    $fbattachment          = array();
    $fbattachment['media'] = array();

    foreach($attachments as $attachment)
    {
        if($enclosure = $attachment->getEnclosure()){
            $fbmedia = get_fbmedia_for_attachment($enclosure);
        }else{
            $fbmedia = get_fbmedia_for_attachment($attachment);
        }
        if($fbmedia){
            $fbattachment['media'][]=$fbmedia;
        }else{
            $fbattachment['name'] = ($attachment->title ?
                                  $attachment->title : $attachment->url);
            $fbattachment['href'] = $attachment->url;
        }
    }
    if(count($fbattachment['media'])>0){
        unset($fbattachment['name']);
        unset($fbattachment['href']);
    }
    return $fbattachment;
}

/**
* given an File objects, returns an associative array suitable for Facebook media
*/
function get_fbmedia_for_attachment($attachment)
{
    $fbmedia    = array();

    if (strncmp($attachment->mimetype, 'image/', strlen('image/')) == 0) {
        $fbmedia['type']         = 'image';
        $fbmedia['src']          = $attachment->url;
        $fbmedia['href']         = $attachment->url;
    } else if ($attachment->mimetype == 'audio/mpeg') {
        $fbmedia['type']         = 'mp3';
        $fbmedia['src']          = $attachment->url;
    }else if ($attachment->mimetype == 'application/x-shockwave-flash') {
        $fbmedia['type']         = 'flash';

        // http://wiki.developers.facebook.com/index.php/Attachment_%28Streams%29
        // says that imgsrc is required... but we have no value to put in it
        // $fbmedia['imgsrc']='';

        $fbmedia['swfsrc']       = $attachment->url;
    }else{
        return false;
    }
    return $fbmedia;
}

function remove_facebook_app($flink)
{

    $user = $flink->getUser();

    common_log(LOG_INFO, 'Removing Facebook App Foreign link for ' .
        "user $user->nickname (user id: $user->id).");

    $result = $flink->delete();

    if (empty($result)) {
        common_log(LOG_ERR, 'Could not remove Facebook App ' .
            "Foreign_link for $user->nickname (user id: $user->id)!");
        common_log_db_error($flink, 'DELETE', __FILE__);
    }

    // Notify the user that we are removing their FB app access

    $result = mail_facebook_app_removed($user);

    if (!$result) {

        $msg = 'Unable to send email to notify ' .
            "$user->nickname (user id: $user->id) " .
            'that their Facebook app link was ' .
            'removed!';

        common_log(LOG_WARNING, $msg);
    }
}

/**
 * Send a mail message to notify a user that her Facebook Application
 * access has been removed.
 *
 * @param User $user   user whose Facebook app link has been removed
 *
 * @return boolean success flag
 */
function mail_facebook_app_removed($user)
{
    $profile = $user->getProfile();

    $site_name = common_config('site', 'name');

    common_switch_locale($user->language);

    $subject = sprintf(
        _m('Your %1$s Facebook application access has been disabled.',
            $site_name));

    $body = sprintf(_m("Hi, %1\$s. We're sorry to inform you that we are " .
        'unable to update your Facebook status from %2$s, and have disabled ' .
        'the Facebook application for your account. This may be because ' .
        'you have removed the Facebook application\'s authorization, or ' .
        'have deleted your Facebook account.  You can re-enable the ' .
        'Facebook application and automatic status updating by ' .
        "re-installing the %2\$s Facebook application.\n\nRegards,\n\n%2\$s"),
        $user->nickname, $site_name);

    common_switch_locale();
    return mail_to_user($user, $subject, $body);
}