<?php
/**
 * StatusNet, the distributed open-source microblogging tool
 *
 * Show the friends timeline
 *
 * PHP version 5
 *
 * LICENCE: 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/>.
 *
 * @category  API
 * @package   StatusNet
 * @author    Craig Andrews <candrews@integralblue.com>
 * @author    Evan Prodromou <evan@status.net>
 * @author    Jeffery To <jeffery.to@gmail.com>
 * @author    mac65 <mac65@mac65.com>
 * @author    Mike Cochrane <mikec@mikenz.geek.nz>
 * @author    Robin Millette <robin@millette.info>
 * @author    Zach Copley <zach@status.net>
 * @copyright 2009-2010 StatusNet, Inc.
 * @copyright 2009 Free Software Foundation, Inc http://www.fsf.org
 * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
 * @link      http://status.net/
 */

/* External API usage documentation. Please update when you change how this method works. */

/*! @page friendstimeline statuses/friends_timeline

    @section Description
    Returns the 20 most recent statuses posted by the authenticating
    user and that user's friends. This is the equivalent of "You and
    friends" page in the web interface.

    @par URL patterns
    @li /api/statuses/friends_timeline.:format
    @li /api/statuses/friends_timeline/:id.:format

    @par Formats (:format)
    xml, json, rss, atom

    @par ID (:id)
    username, user id

    @par HTTP Method(s)
    GET

    @par Requires Authentication
    Sometimes (see: @ref authentication)

    @param user_id (Optional) Specifies a user by ID
    @param screen_name (Optional) Specifies a user by screename (nickname)
    @param since_id (Optional) Returns only statuses with an ID greater
    than (that is, more recent than) the specified ID.
    @param max_id (Optional) Returns only statuses with an ID less than
    (that is, older than) or equal to the specified ID.
    @param count (Optional) Specifies the number of statuses to retrieve.
    @param page (Optional) Specifies the page of results to retrieve.

    @sa @ref authentication
    @sa @ref apiroot

    @subsection usagenotes Usage notes
    @li The URL pattern is relative to the @ref apiroot.
    @li The XML response uses <a href="http://georss.org/Main_Page">GeoRSS</a>
    to encode the latitude and longitude (see example response below <georss:point>).

    @subsection exampleusage Example usage

    @verbatim
    curl http://identi.ca/api/statuses/friends_timeline/evan.xml?count=1&page=2
    @endverbatim

    @subsection exampleresponse Example response

    @verbatim
    <?xml version="1.0"?>
    <statuses type="array">
      <status>
        <text>back from the !yul !drupal meet with Evolving Web folk, @anarcat, @webchick and others, and an interesting refresher on SQL indexing</text>
        <truncated>false</truncated>
        <created_at>Wed Mar 31 01:33:02 +0000 2010</created_at>
        <in_reply_to_status_id/>
        <source>&lt;a href="http://code.google.com/p/microblog-purple/"&gt;mbpidgin&lt;/a&gt;</source>
        <id>26674201</id>
        <in_reply_to_user_id/>
        <in_reply_to_screen_name/>
        <geo/>
        <favorited>false</favorited>
        <user>
          <id>246</id>
          <name>Mark</name>
          <screen_name>lambic</screen_name>
          <location>Montreal, Canada</location>
          <description>Geek</description>
          <profile_image_url>http://avatar.identi.ca/246-48-20080702141545.png</profile_image_url>
          <url>http://lambic.co.uk</url>
          <protected>false</protected>
          <followers_count>73</followers_count>
          <profile_background_color>#F0F2F5</profile_background_color>
          <profile_text_color/>
          <profile_link_color>#002E6E</profile_link_color>
          <profile_sidebar_fill_color>#CEE1E9</profile_sidebar_fill_color>
          <profile_sidebar_border_color/>
          <friends_count>58</friends_count>
          <created_at>Wed Jul 02 14:12:15 +0000 2008</created_at>
          <favourites_count>2</favourites_count>
          <utc_offset>-14400</utc_offset>
          <time_zone>US/Eastern</time_zone>
          <profile_background_image_url/>
          <profile_background_tile>false</profile_background_tile>
          <statuses_count>933</statuses_count>
          <following>false</following>
          <notifications>false</notifications>
        </user>
      </status>
    </statuses>
    @endverbatim
*/

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

require_once INSTALLDIR . '/lib/apibareauth.php';

/**
 * Returns the most recent notices (default 20) posted by the target user.
 * This is the equivalent of 'You and friends' page accessed via Web.
 *
 * @category API
 * @package  StatusNet
 * @author   Craig Andrews <candrews@integralblue.com>
 * @author   Evan Prodromou <evan@status.net>
 * @author   Jeffery To <jeffery.to@gmail.com>
 * @author   mac65 <mac65@mac65.com>
 * @author   Mike Cochrane <mikec@mikenz.geek.nz>
 * @author   Robin Millette <robin@millette.info>
 * @author   Zach Copley <zach@status.net>
 * @license  http://www.fsf.org/licensing/licenses/agpl-3.0.html GNU Affero General Public License version 3.0
 * @link     http://status.net/
 */
class ApiTimelineFriendsAction extends ApiBareAuthAction
{
    var $notices  = null;

    /**
     * Take arguments for running
     *
     * @param array $args $_REQUEST args
     *
     * @return boolean success flag
     *
     */
    function prepare($args)
    {
        parent::prepare($args);
        $this->user = $this->getTargetUser($this->arg('id'));

        if (empty($this->user)) {
            // TRANS: Client error displayed when requesting dents of a user and friends for a user that does not exist.
            $this->clientError(_('No such user.'), 404, $this->format);
            return;
        }

        $this->notices = $this->getNotices();

        return true;
    }

    /**
     * Handle the request
     *
     * Just show the notices
     *
     * @param array $args $_REQUEST data (unused)
     *
     * @return void
     */
    function handle($args)
    {
        parent::handle($args);
        $this->showTimeline();
    }

    /**
     * Show the timeline of notices
     *
     * @return void
     */
    function showTimeline()
    {
        $profile    = $this->user->getProfile();
        $avatar     = $profile->getAvatar(AVATAR_PROFILE_SIZE);
        $sitename   = common_config('site', 'name');
        // TRANS: Title of API timeline for a user and friends.
        // TRANS: %s is a username.
        $title      = sprintf(_("%s and friends"), $this->user->nickname);
        $taguribase = TagURI::base();
        $id         = "tag:$taguribase:FriendsTimeline:" . $this->user->id;

        $subtitle = sprintf(
            // TRANS: Message is used as a subtitle. %1$s is a user nickname, %2$s is a site name.
            _('Updates from %1$s and friends on %2$s!'),
            $this->user->nickname,
            $sitename
        );

        $link = common_local_url(
            'all',
             array('nickname' => $this->user->nickname)
        );

        $self = $this->getSelfUri();

        $logo = (!empty($avatar))
            ? $avatar->displayUrl()
            : Avatar::defaultImage(AVATAR_PROFILE_SIZE);

        switch($this->format) {
        case 'xml':
            $this->showXmlTimeline($this->notices);
            break;
        case 'rss':

            $this->showRssTimeline(
                $this->notices,
                $title,
                $link,
                $subtitle,
                null,
                $logo,
                $self
            );
            break;
        case 'atom':
            header('Content-Type: application/atom+xml; charset=utf-8');

            $atom = new AtomNoticeFeed($this->auth_user);

            $atom->setId($id);
            $atom->setTitle($title);
            $atom->setSubtitle($subtitle);
            $atom->setLogo($logo);
            $atom->setUpdated('now');
            $atom->addLink($link);
            $atom->setSelfLink($self);

            $atom->addEntryFromNotices($this->notices);

            $this->raw($atom->getString());

            break;
        case 'json':
            $this->showJsonTimeline($this->notices);
            break;
        case 'as':
            header('Content-Type: application/json; charset=utf-8');
            $doc = new ActivityStreamJSONDocument($this->auth_user);
            $doc->setTitle($title);
            $doc->addLink($link,'alternate', 'text/html');
            $doc->addItemsFromNotices($this->notices);
            $this->raw($doc->asString());
            break;
        default:
            // TRANS: Client error displayed when coming across a non-supported API method.
            $this->clientError(_('API method not found.'), $code = 404);
            break;
        }
    }

    /**
     * Get notices
     *
     * @return array notices
     */
    function getNotices()
    {
        $notices = array();

        $stream = new InboxNoticeStream($this->user);
        
        $notice = $stream->getNotices(($this->page-1) * $this->count,
                                      $this->count,
                                      $this->since_id,
                                      $this->max_id);

        while ($notice->fetch()) {
            $notices[] = clone($notice);
        }

        return $notices;
    }

    /**
     * Is this action read only?
     *
     * @param array $args other arguments
     *
     * @return boolean true
     */
    function isReadOnly($args)
    {
        return true;
    }

    /**
     * When was this feed last modified?
     *
     * @return string datestamp of the latest notice in the stream
     */
    function lastModified()
    {
        if (!empty($this->notices) && (count($this->notices) > 0)) {
            return strtotime($this->notices[0]->created);
        }

        return null;
    }

    /**
     * An entity tag for this stream
     *
     * Returns an Etag based on the action name, language, user ID, and
     * timestamps of the first and last notice in the timeline
     *
     * @return string etag
     */
    function etag()
    {
        if (!empty($this->notices) && (count($this->notices) > 0)) {
            $last = count($this->notices) - 1;

            return '"' . implode(
                                 ':',
                                 array($this->arg('action'),
                                       common_user_cache_hash($this->auth_user),
                                       common_language(),
                                       $this->user->id,
                                       strtotime($this->notices[0]->created),
                                       strtotime($this->notices[$last]->created))
                                 )
              . '"';
        }

        return null;
    }
}