<?php
/**
 * StatusNet, the distributed open-source microblogging tool
 *
 * Show a notice (as a Twitter-style status)
 *
 * 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    Tom Blankenship <mac65@mac65.com>
 * @author    Mike Cochrane <mikec@mikenz.geek.nz>
 * @author    Robin Millette <robin@millette.info>
 * @author    Zach Copley <zach@status.net>
 * @copyright 2009 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/
 */

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

/**
 * Returns the notice specified by id as a Twitter-style status and inline user
 *
 * @category API
 * @package  StatusNet
 * @author   Craig Andrews <candrews@integralblue.com>
 * @author   Evan Prodromou <evan@status.net>
 * @author   Jeffery To <jeffery.to@gmail.com>
 * @author   Tom Blankenship <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 ApiStatusesShowAction extends ApiPrivateAuthAction
{
    var $notice_id = null;
    var $notice    = null;

    /**
     * Take arguments for running
     *
     * @param array $args $_REQUEST args
     *
     * @return boolean success flag
     */
    protected function prepare(array $args=array())
    {
        parent::prepare($args);

        // 'id' is an undocumented parameter in Twitter's API. Several
        // clients make use of it, so we support it too.

        // show.json?id=12345 takes precedence over /show/12345.json

        $this->notice_id = (int)$this->trimmed('id');

        $this->notice = Notice::getKV('id', $this->notice_id);
        if (!$this->notice instanceof Notice) {
            $deleted = Deleted_notice::getKV('id', $this->notice_id);
            if ($deleted instanceof Deleted_notice) {
                // TRANS: Client error displayed trying to show a deleted notice.
                $this->clientError(_('Notice deleted.'), 410);
            }
            // TRANS: Client error displayed trying to show a non-existing notice.
            $this->clientError(_('No such notice.'), 404);
        }
        if (!$this->notice->inScope($this->scoped)) {
            // TRANS: Client exception thrown when trying a view a notice the user has no access to.
            throw new ClientException(_('Access restricted.'), 403);
        }

        return true;
    }

    /**
     * Handle the request
     *
     * Check the format and show the notice
     *
     * @return void
     */
    protected function handle()
    {
        parent::handle();

        if (!in_array($this->format, array('xml', 'json', 'atom'))) {
            // TRANS: Client error displayed when coming across a non-supported API method.
            $this->clientError(_('API method not found.'), 404);
        }

        switch ($_SERVER['REQUEST_METHOD']) {
        case 'GET':
            $this->showNotice();
            break;
        case 'DELETE':
            $this->deleteNotice();
            break;
        default:
            // TRANS: Client error displayed calling an unsupported HTTP error in API status show.
            $this->clientError(_('HTTP method not supported.'), 405);
        }
    }

    /**
     * Show the notice
     *
     * @return void
     */
    function showNotice()
    {
        if (!empty($this->notice)) {
            switch ($this->format) {
            case 'xml':
                $this->showSingleXmlStatus($this->notice);
                break;
            case 'json':
                $this->show_single_json_status($this->notice);
                break;
            case 'atom':
                $this->showSingleAtomStatus($this->notice);
                break;
            default:
                // TRANS: Exception thrown requesting an unsupported notice output format.
                // TRANS: %s is the requested output format.
                throw new Exception(sprintf(_("Unsupported format: %s."), $this->format));
            }
        } else {
            // XXX: Twitter just sets a 404 header and doens't bother
            // to return an err msg

            $deleted = Deleted_notice::getKV($this->notice_id);

            if (!empty($deleted)) {
                $this->clientError(
                    // TRANS: Client error displayed requesting a deleted status.
                    _('Status deleted.'),
                    410,
                    $this->format
                );
            } else {
                $this->clientError(
                    // TRANS: Client error displayed requesting a status with an invalid ID.
                    _('No status with that ID found.'),
                    404,
                    $this->format
                );
            }
        }
    }

    /**
     * We expose AtomPub here, so non-GET/HEAD reqs must be read/write.
     *
     * @param array $args other arguments
     *
     * @return boolean true
     */

    function isReadOnly(array $args=array())
    {
        return ($_SERVER['REQUEST_METHOD'] == 'GET' || $_SERVER['REQUEST_METHOD'] == 'HEAD');
    }

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

        return null;
    }

    /**
     * An entity tag for this notice
     *
     * Returns an Etag based on the action name, language, and
     * timestamps of the notice
     *
     * @return string etag
     */
    function etag()
    {
        if (!empty($this->notice)) {

            return '"' . implode(
                ':',
                array($this->arg('action'),
                      common_user_cache_hash($this->auth_user),
                      common_language(),
                      $this->notice->id,
                      strtotime($this->notice->created))
            )
            . '"';
        }

        return null;
    }

    function deleteNotice()
    {
        if ($this->format != 'atom') {
            // TRANS: Client error displayed when trying to delete a notice not using the Atom format.
            $this->clientError(_('Can only delete using the Atom format.'));
        }

        if (empty($this->auth_user) ||
            ($this->notice->profile_id != $this->auth_user->id &&
             !$this->auth_user->hasRight(Right::DELETEOTHERSNOTICE))) {
            // TRANS: Client error displayed when a user has no rights to delete notices of other users.
            $this->clientError(_('Cannot delete this notice.'), 403);
        }

        if (Event::handle('StartDeleteOwnNotice', array($this->auth_user, $this->notice))) {
            $this->notice->delete();
            Event::handle('EndDeleteOwnNotice', array($this->auth_user, $this->notice));
        }

        // @fixme is there better output we could do here?

        header('HTTP/1.1 200 OK');
        header('Content-Type: text/plain');
        // TRANS: Confirmation of notice deletion in API. %d is the ID (number) of the deleted notice.
        print(sprintf(_('Deleted notice %d'), $this->notice->id));
        print("\n");
    }
}