<?php
/**
 * StatusNet - the distributed open-source microblogging tool
 * Copyright (C) 2008, 2009, 2010, StatusNet, Inc.
 * Copyright (C) 2010 Free Software Foundation, 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/>.
 * @copyright 2010 Free Software Foundation, Inc
 *
 * @category  GNUSocial
 * @package   StatusNet
 * @author    Shashi Gowda <connect2shashi@gmail.com>
 * @copyright 2009, 2010, StatusNet, Inc.
 * @copyright 2010, Free Software Foundation, Inc.
 * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html AGPL 3.0
 * @link      http://daisycha.in
 */

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

# Abstract class for social-objects

require_once INSTALLDIR.'/classes/Memcached_DataObject.php';

class SocialObject extends Memcached_DataObject
{
    var $slug=null; # used in cache key

    # save a new object
    static function saveNew($args)
    {
        # save everything, add a
        # Notice entry too.
        # call Notice::saveNew with options
        # like replies, groups and tags.
        # and, cache blowing action.
    }

    function delete()
    {
        # delete me and my associated Notice
        # more cache blowing action
        parent::delete();
    }

    # make an atom entry
    function asAtomEntry()
    {
    }

    # make a json object
    function asJson()
    {
    }

    # return an array for Schema::ensureTable to define the table
    static function tableDef()
    {
        return array();
    }

    # give out a stream, and cache it!
    static function stream($fn, $args, $cachekey, $offset=0, $limit=20, $since_id=0, $max_id=0)
    {
        Notice::stream($fn, $args, $cachekey, $offset, $limit, $since_id, $max_id);
    }

    # try to fetch public stream from the cache if it is there
    # or hit the DB, notice objects FIXME: make this return both
    # notices and social-objects
    function publicStream($offset=0, $limit=20, $since_id=0, $max_id=0)
    {
        $ids = self::stream(array($this, '_publicStreamDirect'),
                              array(),
                              'public:'.self::$slug,
                              $offset, $limit, $since_id, $max_id);
        return self::getStreamByIds($ids);
    }

    # fetch public stream from the db and
    # return the ids of the notices
    # see also: Notice::_publicStreamDirect
    function _publicStreamDirect($offset=0, $limit=20, $since_id=0, $max_id=0)
    {
        # make the code look nice :)
        $table = $this->__table;
        $id = $table.'.id';

        $notice = new Notice();

        $this->joinAdd();
        $this->joinAdd($notice); # join notice table

        $this->selectAdd(); // clears it
        $this->selectAdd($id.' as id');

        $this->orderBy($id.' DESC');

        if (!is_null($offset)) {
            $this->limit($offset, $limit);
        }

        if (common_config('public', 'localonly')) {
            $this->whereAdd('notice.is_local = ' . Notice::LOCAL_PUBLIC);
        } else {
            # -1 == blacklisted, -2 == gateway (i.e. Twitter)
            $this->whereAdd('notice.is_local !='. Notice::LOCAL_NONPUBLIC);
            $this->whereAdd('notice.is_local !='. Notice::GATEWAY);
        }

        if ($since_id != 0) {
            $this->whereAdd($id. ' > ' . $since_id);
        }

        if ($max_id != 0) {
            $this->whereAdd($id. ' <= ' . $max_id);
        }

        $ids = array();

        if ($this->find()) {
            while ($this->fetch()) {
                $ids[] = $this->id;
            }
        }

        $this->free();
        $this = NULL;

        return $ids;
    }

    # get all social-objects by user
    function userStream($user, $offset=0, $limit=NOTICES_PER_PAGE, $since_id=0, $max_id=0)
    {
        // XXX: I'm not sure this is going to be any faster. It probably isn't.
        $ids = self::stream(array($user, '_userSreamDirect'),
                              array($user),
                              'profile:'.$this->slug.':notice_ids:' . $user->id,
                              $offset, $limit, $since_id, $max_id);

        return self::getStreamByIds($ids);
    }

    # some scary, scary (hacked) upstream code follows.
    function _userStreamDirect($user, $offset, $limit, $since_id, $max_id)
    {
        $table = $this->__table;
        $id = $table.'.id';

        $notice = new Notice();

        // Temporary hack until notice_profile_id_idx is updated
        // to (profile_id, id) instead of (profile_id, created, id).
        // It's been falling back to PRIMARY instead, which is really
        // very inefficient for a profile that hasn't posted in a few
        // months. Even though forcing the index will cause a filesort,
        // it's usually going to be better.
        if (common_config('db', 'type') == 'mysql') {
            $index = '';
            $query =    # join me
              "select $id as id from notice join $table on ($id = notice.id) ".
              "force index (notice_profile_id_idx) ".
              "where notice.profile_id=" . $notice->escape($user->id);

            if ($since_id != 0) {
                $query .= " and $id > $since_id";
            }

            if ($max_id != 0) {
                $query .= " and $id < $max_id";
            }

            $query .= " order by $id DESC";

            if (!is_null($offset)) {
                $query .= " LIMIT $limit OFFSET $offset";
            }

            $this->query($query);
        } else {
            $index = '';

            $notice->profile_id = $user->id;

            $this->joinAdd();
            $this->joinAdd($notice);

            $this->selectAdd();
            $this->selectAdd("$id as id");

            if ($since_id != 0) {
                $this->whereAdd("$id > $since_id");
            }

            if ($max_id != 0) {
                $this->whereAdd("$id <= $max_id");
            }

            $this->orderBy("$id DESC");

            if (!is_null($offset)) {
                $this->limit($offset, $limit);
            }

            $this->find();
        }

        $ids = array();

        while ($this->fetch()) {
            $ids[] = $this->id;
        }

        return $ids;
    }

    # get all social-objects in the group
    function groupStream($group, $offset, $limit, $since_id=null, $max_id=null)
    {
        $ids = self::stream(array($this, '_groupStreamDirect'),
                              array($group),
                              'user_group:'.$this->slug.':notice_ids:' . $group->id,
                              $offset, $limit, $since_id, $max_id);

        return self::getStreamByIds($ids);
    }

    function _groupStreamDirect($group, $offset, $limit, $since_id, $max_id)
    {
        $table = $this->__table;

        $inbox = new Group_inbox();

        $inbox->group_id = $group->id;

        $inbox->joinAdd();
        $inbox->joinAdd($this);

        $inbox->selectAdd();
        $inbox->selectAdd('group_inbox.notice_id as id');

        if ($since_id != 0) {
            $inbox->whereAdd('group_inbox.notice_id > ' . $since_id);
        }

        if ($max_id != 0) {
            $inbox->whereAdd('group_inbox.notice_id <= ' . $max_id);
        }

        $inbox->orderBy('group_inbox.notice_id DESC');

        if (!is_null($offset)) {
            $inbox->limit($offset, $limit);
        }

        $ids = array();

        if ($inbox->find()) {
            while ($inbox->fetch()) {
                $ids[] = $inbox->notice_id;
            }
        }

        return $ids;
    }

    # param: array of ids
    # returns: array($notices, $social_objects)
    # an example on how to use this:
    #
    #   list($notices, $objects) = SocialObject::getStreamByIds($ids);
    #   while($notices->fetch()) {
    #       $obj = $objects[$notices->id];
    #       if(!empty($obj)) {
    #           # now use $notices and $obj,
    #           # they are associated.
    #       }
    #   }
    #
    static function getStreamByIds($ids, $classname=null) {
        $notices = Notice::getSteamByIds($ids);
        $objects = array();
        if(empty($classname) && function_exists('get_called_class')) {
            $classname = get_called_class(); # works in php 5.3 +
        }

        $cache = common_memcache();

        # don't put array wrapper around $objects
        # keep the id as key
        if (!empty($cache)) {
            $objects = array();
            foreach ($ids as $id) {
                $n = $classname::staticGet('id', $id);
                if (!empty($n)) {
                    $objects[$id] = $n;
                }
            }
            return array($notices, $objects);
        } else {
            $object = new $classname();
            if (empty($ids)) {
                return array($notices, array());
            }
            $objects->whereAdd('id in (' . implode(', ', $ids) . ')');

            $objects->find();

            $objects = array();

            while ($object->fetch()) {
                $objects[$notice->id] = clone($object);
            }

            # just return the $objects array, we can then use $notices->id
            # each time to get the object associated
            return new array($notices, $objects);
        }
    }
}