<?php
// This file is part of GNU social - https://www.gnu.org/software/social
//
// GNU social 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.
//
// GNU social 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 GNU social.  If not, see <http://www.gnu.org/licenses/>.

/**
 * OembedPlugin implementation for GNU social
 *
 * @package   GNUsocial
 *
 * @author    Craig Andrews <candrews@integralblue.com>
 * @author    Mikael Nordfeldth <mmn@hethane.se>
 * @author    hannes
 * @author    Diogo Cordeiro <diogo@fc.up.pt>
 * @copyright 2019 Free Software Foundation, Inc http://www.fsf.org
 * @license   https://www.gnu.org/licenses/agpl.html GNU AGPL v3 or later
 */

namespace Plguin\Embed\actions;

/**
 * Oembed provider implementation
 *
 * This class handles all /main/oembed(.xml|.json)/ requests.
 *
 * @copyright 2019 Free Software Foundation, Inc http://www.fsf.org
 * @license   https://www.gnu.org/licenses/agpl.html GNU AGPL v3 or later
 */
class OEmbedAction extends Action
{
    /** Placeholder */
    protected function handle()
    {
        parent::handle();

        $url      = $this->trimmed('url');
        $tls      = parse_url($url, PHP_URL_SCHEME) == 'https';
        $root_url = common_root_url($tls);

        if (substr(strtolower($url), 0, mb_strlen($root_url)) !== strtolower($root_url)) {
            // TRANS: Error message displaying attachments. %s is the site's base URL.
            throw new ClientException(sprintf(_('Embed data will only be provided for %s URLs.'), $root_url));
        }

        $path = substr($url, strlen($root_url));

        $r = Router::get();

        // $r->map will throw ClientException 404 if it fails to find a mapping
        $proxy_args = $r->map($path);

        $oembed                  = [];
        $oembed['version']       = '1.0';
        $oembed['provider_name'] = common_config('site', 'name');
        $oembed['provider_url']  = common_root_url();

        switch ($proxy_args['action']) {
        case 'shownotice':
            $oembed['type'] = 'link';
            try {
                $notice = Notice::getByID($proxy_args['notice']);
            } catch (NoResultException $e) {
                throw new ClientException($e->getMessage(), 404);
            }
            $profile    = $notice->getProfile();
            $authorname = $profile->getFancyName();
            // TRANS: oEmbed title. %1$s is the author name, %2$s is the creation date.
            $oembed['title'] = sprintf(
                _('%1$s\'s status on %2$s'),
                $authorname,
                common_exact_date($notice->created)
            );
            $oembed['author_name'] = $authorname;
            $oembed['author_url']  = $profile->profileurl;
            $oembed['url']         = $notice->getUrl();
            $oembed['html']        = $notice->getRendered();

            // maybe add thumbnail
            foreach ($notice->attachments() as $attachment) {
                if (!$attachment instanceof File) {
                    common_debug('ATTACHMENTS array entry from notice id==' . _ve($notice->getID()) .
                                 ' is something else than a File dataobject: ' . _ve($attachment));
                    continue;
                }
                try {
                    $thumb                   = $attachment->getThumbnail();
                    $thumb_url               = $thumb->getUrl();
                    $oembed['thumbnail_url'] = $thumb_url;
                    break;  // only first one
                } catch (UseFileAsThumbnailException $e) {
                    $oembed['thumbnail_url'] = $attachment->getUrl();
                    break;  // we're happy with that
                } catch (ServerException $e) {
                } catch (ClientException $e) {
                }
            }
            break;

        case 'attachment':
            $id         = $proxy_args['attachment'];
            $attachment = File::getKV($id);
            if (empty($attachment)) {
                // TRANS: Client error displayed in oEmbed action when attachment not found.
                // TRANS: %d is an attachment ID.
                $this->clientError(sprintf(_('Attachment %s not found.'), $id), 404);
            }
            if (
                empty($attachment->filename)
                && !empty($file_oembed = File_oembed::getKV(
                    'file_id',
                    $attachment->id
                ))
            ) {
                // Proxy the existing oembed information
                $oembed['type']         = $file_oembed->type;
                $oembed['provider']     = $file_oembed->provider;
                $oembed['provider_url'] = $file_oembed->provider_url;
                $oembed['width']        = $file_oembed->width;
                $oembed['height']       = $file_oembed->height;
                $oembed['html']         = $file_oembed->html;
                $oembed['title']        = $file_oembed->title;
                $oembed['author_name']  = $file_oembed->author_name;
                $oembed['author_url']   = $file_oembed->author_url;
                $oembed['url']          = $file_oembed->getUrl();
            } elseif (substr($attachment->mimetype, 0, strlen('image/')) === 'image/') {
                $oembed['type'] = 'photo';
                if ($attachment->filename) {
                    $filepath = File::path($attachment->filename);
                    $gis      = @getimagesize($filepath);
                    if ($gis) {
                        $oembed['width']  = $gis[0];
                        $oembed['height'] = $gis[1];
                    } else {
                        // TODO Either throw an error or find a fallback?
                    }
                }
                $oembed['url'] = $attachment->getUrl();
                try {
                    $thumb                      = $attachment->getThumbnail();
                    $oembed['thumbnail_url']    = $thumb->getUrl();
                    $oembed['thumbnail_width']  = $thumb->width;
                    $oembed['thumbnail_height'] = $thumb->height;
                    unset($thumb);
                } catch (UnsupportedMediaException $e) {
                    // No thumbnail data available
                }
            } else {
                $oembed['type'] = 'link';
                $oembed['url']  = common_local_url(
                    'attachment',
                    ['attachment' => $attachment->id]
                );
            }
            if ($attachment->title) {
                $oembed['title'] = $attachment->title;
            }
            break;
        default:
            // TRANS: Server error displayed in oEmbed request when a path is not supported.
            // TRANS: %s is a path.
            $this->serverError(sprintf(_('"%s" not supported for oembed requests.'), $path), 501);
        }

        switch ($this->trimmed('format')) {
        case 'xml':
            $this->init_document('xml');
            $this->elementStart('oembed');
            foreach ([
                'version', 'type', 'provider_name',
                'provider_url', 'title', 'author_name',
                'author_url', 'url', 'html', 'width',
                'height', 'cache_age', 'thumbnail_url',
                'thumbnail_width', 'thumbnail_height',
            ] as $key) {
                if (isset($oembed[$key]) && $oembed[$key] != '') {
                    $this->element($key, null, $oembed[$key]);
                }
            }
            $this->elementEnd('oembed');
            $this->end_document('xml');
            break;

        case 'json':
        case null:
            $this->init_document('json');
            $this->raw(json_encode($oembed));
            $this->end_document('json');
            break;
        default:
            // TRANS: Error message displaying attachments. %s is a raw MIME type (eg 'image/png')
            $this->serverError(sprintf(_('Content type %s not supported.'), $apidata['content-type']), 501);
        }
    }

    /** Placeholder */
    public function init_document($type)
    {
        switch ($type) {
        case 'xml':
            header('Content-Type: application/xml; charset=utf-8');
            $this->startXML();
            break;
        case 'json':
            header('Content-Type: application/json; charset=utf-8');

            // Check for JSONP callback
            $callback = $this->arg('callback');
            if ($callback) {
                echo $callback . '(';
            }
            break;
        default:
            // TRANS: Server error displayed in oEmbed action when request specifies an unsupported data format.
            $this->serverError(_('Not a supported data format.'), 501);
            break;
        }
    }

    /** Placeholder */
    public function end_document($type)
    {
        switch ($type) {
        case 'xml':
            $this->endXML();
            break;
        case 'json':
            // Check for JSONP callback
            $callback = $this->arg('callback');
            if ($callback) {
                echo ')';
            }
            break;
        default:
            // TRANS: Server error displayed in oEmbed action when request specifies an unsupported data format.
            $this->serverError(_('Not a supported data format.'), 501);
            break;
        }
    }

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