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1 <?php
2 /**
3  * StatusNet, the distributed open-source microblogging tool
4  *
5  * An activity
6  *
7  * PHP version 5
8  *
9  * LICENCE: This program is free software: you can redistribute it and/or modify
10  * it under the terms of the GNU Affero General Public License as published by
11  * the Free Software Foundation, either version 3 of the License, or
12  * (at your option) any later version.
13  *
14  * This program is distributed in the hope that it will be useful,
15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17  * GNU Affero General Public License for more details.
18  *
19  * You should have received a copy of the GNU Affero General Public License
20  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
21  *
22  * @category  Feed
23  * @package   StatusNet
24  * @author    Evan Prodromou <evan@status.net>
25  * @author    Zach Copley <zach@status.net>
26  * @copyright 2010 StatusNet, Inc.
27  * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html AGPLv3
28  * @link      http://status.net/
29  */
30
31 if (!defined('STATUSNET')) {
32     exit(1);
33 }
34
35 /**
36  * A noun-ish thing in the activity universe
37  *
38  * The activity streams spec talks about activity objects, while also having
39  * a tag activity:object, which is in fact an activity object. Aaaaaah!
40  *
41  * This is just a thing in the activity universe. Can be the subject, object,
42  * or indirect object (target!) of an activity verb. Rotten name, and I'm
43  * propagating it. *sigh*
44  *
45  * @category  OStatus
46  * @package   StatusNet
47  * @author    Evan Prodromou <evan@status.net>
48  * @copyright 2010 StatusNet, Inc.
49  * @license   http://www.fsf.org/licensing/licenses/agpl-3.0.html AGPLv3
50  * @link      http://status.net/
51  */
52 class ActivityObject
53 {
54     const ARTICLE   = 'http://activitystrea.ms/schema/1.0/article';
55     const BLOGENTRY = 'http://activitystrea.ms/schema/1.0/blog-entry';
56     const NOTE      = 'http://activitystrea.ms/schema/1.0/note';
57     const STATUS    = 'http://activitystrea.ms/schema/1.0/status';
58     const FILE      = 'http://activitystrea.ms/schema/1.0/file';
59     const PHOTO     = 'http://activitystrea.ms/schema/1.0/photo';
60     const ALBUM     = 'http://activitystrea.ms/schema/1.0/photo-album';
61     const PLAYLIST  = 'http://activitystrea.ms/schema/1.0/playlist';
62     const VIDEO     = 'http://activitystrea.ms/schema/1.0/video';
63     const AUDIO     = 'http://activitystrea.ms/schema/1.0/audio';
64     const BOOKMARK  = 'http://activitystrea.ms/schema/1.0/bookmark';
65     const PERSON    = 'http://activitystrea.ms/schema/1.0/person';
66     const GROUP     = 'http://activitystrea.ms/schema/1.0/group';
67     const _LIST     = 'http://activitystrea.ms/schema/1.0/list'; // LIST is reserved
68     const PLACE     = 'http://activitystrea.ms/schema/1.0/place';
69     const COMMENT   = 'http://activitystrea.ms/schema/1.0/comment';
70     // ^^^^^^^^^^ tea!
71     const ACTIVITY = 'http://activitystrea.ms/schema/1.0/activity';
72     const SERVICE   = 'http://activitystrea.ms/schema/1.0/service';
73     const IMAGE     = 'http://activitystrea.ms/schema/1.0/image';
74     const COLLECTION = 'http://activitystrea.ms/schema/1.0/collection';
75     const APPLICATION = 'http://activitystrea.ms/schema/1.0/application';
76
77     // Atom elements we snarf
78
79     const TITLE   = 'title';
80     const SUMMARY = 'summary';
81     const ID      = 'id';
82     const SOURCE  = 'source';
83
84     const NAME  = 'name';
85     const URI   = 'uri';
86     const EMAIL = 'email';
87
88     const POSTEROUS   = 'http://posterous.com/help/rss/1.0';
89     const AUTHOR      = 'author';
90     const USERIMAGE   = 'userImage';
91     const PROFILEURL  = 'profileUrl';
92     const NICKNAME    = 'nickName';
93     const DISPLAYNAME = 'displayName';
94
95     public $element;
96     public $type;
97     public $id;
98     public $title;
99     public $summary;
100     public $content;
101     public $owner;
102     public $link;
103     public $source;
104     public $avatarLinks = array();
105     public $geopoint;
106     public $poco;
107     public $displayName;
108
109     // @todo move this stuff to it's own PHOTO activity object
110     const MEDIA_DESCRIPTION = 'description';
111
112     public $thumbnail;
113     public $largerImage;
114     public $description;
115     public $extra = array();
116
117     public $stream;
118
119     /**
120      * Constructor
121      *
122      * This probably needs to be refactored
123      * to generate a local class (ActivityPerson, ActivityFile, ...)
124      * based on the object type.
125      *
126      * @param DOMElement $element DOM thing to turn into an Activity thing
127      */
128     function __construct($element = null)
129     {
130         if (empty($element)) {
131             return;
132         }
133
134         $this->element = $element;
135
136         $this->geopoint = $this->_childContent(
137             $element,
138             ActivityContext::POINT,
139             ActivityContext::GEORSS
140         );
141
142         if ($element->tagName == 'author') {
143             $this->_fromAuthor($element);
144         } else if ($element->tagName == 'item') {
145             $this->_fromRssItem($element);
146         } else {
147             $this->_fromAtomEntry($element);
148         }
149
150         // Some per-type attributes...
151         if ($this->type == self::PERSON || $this->type == self::GROUP) {
152             $this->displayName = $this->title;
153
154             $photos = ActivityUtils::getLinks($element, 'photo');
155             if (count($photos)) {
156                 foreach ($photos as $link) {
157                     $this->avatarLinks[] = new AvatarLink($link);
158                 }
159             } else {
160                 $avatars = ActivityUtils::getLinks($element, 'avatar');
161                 foreach ($avatars as $link) {
162                     $this->avatarLinks[] = new AvatarLink($link);
163                 }
164             }
165
166             $this->poco = new PoCo($element);
167         }
168
169         if ($this->type == self::PHOTO) {
170
171             $this->thumbnail   = ActivityUtils::getLink($element, 'preview');
172             $this->largerImage = ActivityUtils::getLink($element, 'enclosure');
173
174             $this->description = ActivityUtils::childContent(
175                 $element,
176                 ActivityObject::MEDIA_DESCRIPTION,
177                 Activity::MEDIA
178             );
179         }
180         if ($this->type == self::_LIST) {
181             $owner = ActivityUtils::child($this->element, Activity::AUTHOR, Activity::SPEC);
182             $this->owner = new ActivityObject($owner);
183         }
184     }
185
186     private function _fromAuthor($element)
187     {
188         $this->type = $this->_childContent($element,
189                                            Activity::OBJECTTYPE,
190                                            Activity::SPEC);
191
192         if (empty($this->type)) {
193             $this->type = self::PERSON; // XXX: is this fair?
194         }
195
196         // start with <atom:title>
197
198         $title = ActivityUtils::childHtmlContent($element, self::TITLE);
199
200         if (!empty($title)) {
201             $this->title = html_entity_decode(strip_tags($title), ENT_QUOTES, 'UTF-8');
202         }
203
204         // fall back to <atom:name>
205
206         if (empty($this->title)) {
207             $this->title = $this->_childContent($element, self::NAME);
208         }
209
210         // start with <atom:id>
211
212         $this->id = $this->_childContent($element, self::ID);
213
214         // fall back to <atom:uri>
215
216         if (empty($this->id)) {
217             $this->id = $this->_childContent($element, self::URI);
218         }
219
220         // fall further back to <atom:email>
221
222         if (empty($this->id)) {
223             $email = $this->_childContent($element, self::EMAIL);
224             if (!empty($email)) {
225                 // XXX: acct: ?
226                 $this->id = 'mailto:'.$email;
227             }
228         }
229
230         $this->link = ActivityUtils::getPermalink($element);
231
232         // fall finally back to <link rel=alternate>
233
234         if (empty($this->id) && !empty($this->link)) { // fallback if there's no ID
235             $this->id = $this->link;
236         }
237     }
238
239     private function _fromAtomEntry($element)
240     {
241         $this->type = $this->_childContent($element, Activity::OBJECTTYPE,
242                                            Activity::SPEC);
243
244         if (empty($this->type)) {
245             $this->type = ActivityObject::NOTE;
246         }
247
248         $this->summary = ActivityUtils::childHtmlContent($element, self::SUMMARY);
249         $this->content = ActivityUtils::getContent($element);
250
251         // We don't like HTML in our titles, although it's technically allowed
252
253         $title = ActivityUtils::childHtmlContent($element, self::TITLE);
254
255         $this->title = html_entity_decode(strip_tags($title), ENT_QUOTES, 'UTF-8');
256
257         $this->source  = $this->_getSource($element);
258
259         $this->link = ActivityUtils::getPermalink($element);
260
261         $this->id = $this->_childContent($element, self::ID);
262
263         if (empty($this->id) && !empty($this->link)) { // fallback if there's no ID
264             $this->id = $this->link;
265         }
266     }
267
268     // @todo FIXME: rationalize with Activity::_fromRssItem()
269     private function _fromRssItem($item)
270     {
271         $this->title = ActivityUtils::childContent($item, ActivityObject::TITLE, Activity::RSS);
272
273         $contentEl = ActivityUtils::child($item, ActivityUtils::CONTENT, Activity::CONTENTNS);
274
275         if (!empty($contentEl)) {
276             $this->content = htmlspecialchars_decode($contentEl->textContent, ENT_QUOTES);
277         } else {
278             $descriptionEl = ActivityUtils::child($item, Activity::DESCRIPTION, Activity::RSS);
279             if (!empty($descriptionEl)) {
280                 $this->content = htmlspecialchars_decode($descriptionEl->textContent, ENT_QUOTES);
281             }
282         }
283
284         $this->link = ActivityUtils::childContent($item, ActivityUtils::LINK, Activity::RSS);
285
286         $guidEl = ActivityUtils::child($item, Activity::GUID, Activity::RSS);
287
288         if (!empty($guidEl)) {
289             $this->id = $guidEl->textContent;
290
291             if ($guidEl->hasAttribute('isPermaLink')) {
292                 // overwrites <link>
293                 $this->link = $this->id;
294             }
295         }
296     }
297
298     public static function fromRssAuthor($el)
299     {
300         $text = $el->textContent;
301
302         if (preg_match('/^(.*?) \((.*)\)$/', $text, $match)) {
303             $email = $match[1];
304             $name = $match[2];
305         } else if (preg_match('/^(.*?) <(.*)>$/', $text, $match)) {
306             $name = $match[1];
307             $email = $match[2];
308         } else if (preg_match('/.*@.*/', $text)) {
309             $email = $text;
310             $name = null;
311         } else {
312             $name = $text;
313             $email = null;
314         }
315
316         // Not really enough info
317
318         $obj = new ActivityObject();
319
320         $obj->element = $el;
321
322         $obj->type  = ActivityObject::PERSON;
323         $obj->title = $name;
324
325         if (!empty($email)) {
326             $obj->id = 'mailto:'.$email;
327         }
328
329         return $obj;
330     }
331
332     public static function fromDcCreator($el)
333     {
334         // Not really enough info
335
336         $text = $el->textContent;
337
338         $obj = new ActivityObject();
339
340         $obj->element = $el;
341
342         $obj->title = $text;
343         $obj->type  = ActivityObject::PERSON;
344
345         return $obj;
346     }
347
348     public static function fromRssChannel($el)
349     {
350         $obj = new ActivityObject();
351
352         $obj->element = $el;
353
354         $obj->type = ActivityObject::PERSON; // @fixme guess better
355
356         $obj->title = ActivityUtils::childContent($el, ActivityObject::TITLE, Activity::RSS);
357         $obj->link  = ActivityUtils::childContent($el, ActivityUtils::LINK, Activity::RSS);
358         $obj->id    = ActivityUtils::getLink($el, Activity::SELF);
359
360         if (empty($obj->id)) {
361             $obj->id = $obj->link;
362         }
363
364         $desc = ActivityUtils::childContent($el, Activity::DESCRIPTION, Activity::RSS);
365
366         if (!empty($desc)) {
367             $obj->content = htmlspecialchars_decode($desc, ENT_QUOTES);
368         }
369
370         $imageEl = ActivityUtils::child($el, Activity::IMAGE, Activity::RSS);
371
372         if (!empty($imageEl)) {
373             $url = ActivityUtils::childContent($imageEl, Activity::URL, Activity::RSS);
374             $al = new AvatarLink();
375             $al->url = $url;
376             $obj->avatarLinks[] = $al;
377         }
378
379         return $obj;
380     }
381
382     public static function fromPosterousAuthor($el)
383     {
384         $obj = new ActivityObject();
385
386         $obj->type = ActivityObject::PERSON; // @fixme any others...?
387
388         $userImage = ActivityUtils::childContent($el, self::USERIMAGE, self::POSTEROUS);
389
390         if (!empty($userImage)) {
391             $al = new AvatarLink();
392             $al->url = $userImage;
393             $obj->avatarLinks[] = $al;
394         }
395
396         $obj->link = ActivityUtils::childContent($el, self::PROFILEURL, self::POSTEROUS);
397         $obj->id   = $obj->link;
398
399         $obj->poco = new PoCo();
400
401         $obj->poco->preferredUsername = ActivityUtils::childContent($el, self::NICKNAME, self::POSTEROUS);
402         $obj->poco->displayName       = ActivityUtils::childContent($el, self::DISPLAYNAME, self::POSTEROUS);
403
404         $obj->title = $obj->poco->displayName;
405
406         return $obj;
407     }
408
409     private function _childContent($element, $tag, $namespace=ActivityUtils::ATOM)
410     {
411         return ActivityUtils::childContent($element, $tag, $namespace);
412     }
413
414     // Try to get a unique id for the source feed
415
416     private function _getSource($element)
417     {
418         $sourceEl = ActivityUtils::child($element, 'source');
419
420         if (empty($sourceEl)) {
421             return null;
422         } else {
423             $href = ActivityUtils::getLink($sourceEl, 'self');
424             if (!empty($href)) {
425                 return $href;
426             } else {
427                 return ActivityUtils::childContent($sourceEl, 'id');
428             }
429         }
430     }
431
432     static function fromNotice(Notice $notice)
433     {
434         $object = new ActivityObject();
435
436         if (Event::handle('StartActivityObjectFromNotice', array($notice, &$object))) {
437
438             $object->type    = (empty($notice->object_type)) ? ActivityObject::NOTE : $notice->object_type;
439
440             $object->id      = $notice->uri;
441             $object->title   = 'New ' . ActivityObject::canonicalType($notice->object_type)
442                                 . ' by ' . $notice->getProfile()->nickname;
443             $object->content = $notice->rendered;
444             $object->link    = $notice->bestUrl();
445
446             $object->extra[] = array('status_net', array('notice_id' => $notice->id));
447
448             Event::handle('EndActivityObjectFromNotice', array($notice, &$object));
449         }
450
451         return $object;
452     }
453
454     static function fromProfile(Profile $profile)
455     {
456         $object = new ActivityObject();
457
458         if (Event::handle('StartActivityObjectFromProfile', array($profile, &$object))) {
459             $object->type   = ActivityObject::PERSON;
460             $object->id     = $profile->getUri();
461             $object->title  = $profile->getBestName();
462             $object->link   = $profile->profileurl;
463
464             try {
465                 $avatar = Avatar::getUploaded($profile);
466                 $object->avatarLinks[] = AvatarLink::fromAvatar($avatar);
467             } catch (NoAvatarException $e) {
468                 // Could not find an original avatar to link
469             }
470
471             $sizes = array(
472                 AVATAR_PROFILE_SIZE,
473                 AVATAR_STREAM_SIZE,
474                 AVATAR_MINI_SIZE
475             );
476
477             foreach ($sizes as $size) {
478                 $alink  = null;
479                 try {
480                     $avatar = Avatar::byProfile($profile, $size);
481                     $alink = AvatarLink::fromAvatar($avatar);
482                 } catch (NoAvatarException $e) {
483                     $alink = new AvatarLink();
484                     $alink->type   = 'image/png';
485                     $alink->height = $size;
486                     $alink->width  = $size;
487                     $alink->url    = Avatar::defaultImage($size);
488                 }
489
490                 $object->avatarLinks[] = $alink;
491             }
492
493             if (isset($profile->lat) && isset($profile->lon)) {
494                 $object->geopoint = (float)$profile->lat
495                     . ' ' . (float)$profile->lon;
496             }
497
498             $object->poco = PoCo::fromProfile($profile);
499
500             if ($profile->isLocal()) {
501                 $object->extra[] = array('followers', array('url' => common_local_url('subscribers', array('nickname' => $profile->nickname))));
502             }
503
504             Event::handle('EndActivityObjectFromProfile', array($profile, &$object));
505         }
506
507         return $object;
508     }
509
510     static function fromGroup(User_group $group)
511     {
512         $object = new ActivityObject();
513
514         if (Event::handle('StartActivityObjectFromGroup', array($group, &$object))) {
515
516             $object->type   = ActivityObject::GROUP;
517             $object->id     = $group->getUri();
518             $object->title  = $group->getBestName();
519             $object->link   = $group->getUri();
520
521             $object->avatarLinks[] = AvatarLink::fromFilename($group->homepage_logo,
522                                                               AVATAR_PROFILE_SIZE);
523
524             $object->avatarLinks[] = AvatarLink::fromFilename($group->stream_logo,
525                                                               AVATAR_STREAM_SIZE);
526
527             $object->avatarLinks[] = AvatarLink::fromFilename($group->mini_logo,
528                                                               AVATAR_MINI_SIZE);
529
530             $object->poco = PoCo::fromGroup($group);
531             Event::handle('EndActivityObjectFromGroup', array($group, &$object));
532         }
533
534         return $object;
535     }
536
537     static function fromPeopletag($ptag)
538     {
539         $object = new ActivityObject();
540         if (Event::handle('StartActivityObjectFromPeopletag', array($ptag, &$object))) {
541             $object->type    = ActivityObject::_LIST;
542
543             $object->id      = $ptag->getUri();
544             $object->title   = $ptag->tag;
545             $object->summary = $ptag->description;
546             $object->link    = $ptag->homeUrl();
547             $object->owner   = Profile::getKV('id', $ptag->tagger);
548             $object->poco    = PoCo::fromProfile($object->owner);
549             Event::handle('EndActivityObjectFromPeopletag', array($ptag, &$object));
550         }
551         return $object;
552     }
553
554     static function fromFile(File $file)
555     {
556         $object = new ActivityObject();
557
558         if (Event::handle('StartActivityObjectFromFile', array($file, &$object))) {
559
560             $object->type = self::mimeTypeToObjectType($file->mimetype);
561             $object->id   = TagURI::mint(sprintf("file:%d", $file->id));
562             $object->link = common_local_url('attachment', array('attachment' => $file->id));
563
564             if ($file->title) {
565                 $object->title = $file->title;
566             }
567
568             if ($file->date) {
569                 $object->date = $file->date;
570             }
571
572             $thumbnail = $file->getThumbnail();
573
574             if (!empty($thumbnail)) {
575                 $object->thumbnail = $thumbnail;
576             }
577
578             switch (ActivityObject::canonicalType($object->type)) {
579             case 'image':
580                 $object->largerImage = $file->url;
581                 break;
582             case 'video':
583             case 'audio':
584                 $object->stream = $file->url;
585                 break;
586             }
587
588             Event::handle('EndActivityObjectFromFile', array($file, &$object));
589         }
590
591         return $object;
592     }
593
594     static function fromNoticeSource(Notice_source $source)
595     {
596         $object = new ActivityObject();
597         $wellKnown = array('web', 'xmpp', 'mail', 'omb', 'system', 'api', 'ostatus',
598                            'activity', 'feed', 'mirror', 'twitter', 'facebook');
599
600         if (Event::handle('StartActivityObjectFromNoticeSource', array($source, &$object))) {
601             $object->type = ActivityObject::APPLICATION;
602
603             if (in_array($source->code, $wellKnown)) {
604                 // We use one ID for all well-known StatusNet sources
605                 $object->id = "tag:status.net,2009:notice-source:".$source->code;
606             } else if ($source->url) {
607                 // They registered with an URL
608                 $object->id = $source->url;
609             } else {
610                 // Locally-registered, no URL
611                 $object->id = TagURI::mint("notice-source:".$source->code);
612             }
613
614             if ($source->url) {
615                 $object->link = $source->url;
616             }
617
618             if ($source->name) {
619                 $object->title = $source->name;
620             } else {
621                 $object->title = $source->code;
622             }
623
624             if ($source->created) {
625                 $object->date = $source->created;
626             }
627             
628             $object->extra[] = array('status_net', array('source_code' => $source->code));
629
630             Event::handle('EndActivityObjectFromNoticeSource', array($source, &$object));
631         }
632
633         return $object;
634     }
635
636     static function fromMessage(Message $message)
637     {
638         $object = new ActivityObject();
639
640         if (Event::handle('StartActivityObjectFromMessage', array($message, &$object))) {
641
642             $object->type    = ActivityObject::NOTE;
643             $object->id      = ($message->uri) ? $message->uri : (($message->url) ? $message->url : TagURI::mint(sprintf("message:%d", $message->id)));
644             $object->content = $message->rendered;
645             $object->date    = $message->created;
646
647             if ($message->url) {
648                 $object->link = $message->url;
649             } else {
650                 $object->link = common_local_url('showmessage', array('message' => $message->id));
651             }
652
653             $object->extra[] = array('status_net', array('message_id' => $message->id));
654             
655             Event::handle('EndActivityObjectFromMessage', array($message, &$object));
656         }
657
658         return $object;
659     }
660
661     function outputTo($xo, $tag='activity:object')
662     {
663         if (!empty($tag)) {
664             $xo->elementStart($tag);
665         }
666
667         if (Event::handle('StartActivityObjectOutputAtom', array($this, $xo))) {
668             $xo->element('activity:object-type', null, $this->type);
669
670             // <author> uses URI
671
672             if ($tag == 'author') {
673                 $xo->element(self::URI, null, $this->id);
674             } else {
675                 $xo->element(self::ID, null, $this->id);
676             }
677
678             if (!empty($this->title)) {
679                 $name = common_xml_safe_str($this->title);
680                 if ($tag == 'author') {
681                     // XXX: Backward compatibility hack -- atom:name should contain
682                     // full name here, instead of nickname, i.e.: $name. Change
683                     // this in the next version.
684                     $xo->element(self::NAME, null, $this->poco->preferredUsername);
685                 } else {
686                     $xo->element(self::TITLE, null, $name);
687                 }
688             }
689
690             if (!empty($this->summary)) {
691                 $xo->element(
692                     self::SUMMARY,
693                     null,
694                     common_xml_safe_str($this->summary)
695                 );
696             }
697
698             if (!empty($this->content)) {
699                 // XXX: assuming HTML content here
700                 $xo->element(
701                     ActivityUtils::CONTENT,
702                     array('type' => 'html'),
703                     common_xml_safe_str($this->content)
704                 );
705             }
706
707             if (!empty($this->link)) {
708                 $xo->element(
709                     'link',
710                     array(
711                         'rel' => 'alternate',
712                         'type' => 'text/html',
713                         'href' => $this->link
714                     ),
715                     null
716                 );
717             }
718
719             if(!empty($this->owner)) {
720                 $owner = $this->owner->asActivityNoun(self::AUTHOR);
721                 $xo->raw($owner);
722             }
723
724             if ($this->type == ActivityObject::PERSON
725                 || $this->type == ActivityObject::GROUP) {
726
727                 foreach ($this->avatarLinks as $alink) {
728                     $xo->element('link',
729                             array(
730                                 'rel'          => 'avatar',
731                                 'type'         => $alink->type,
732                                 'media:width'  => $alink->width,
733                                 'media:height' => $alink->height,
734                                 'href'         => $alink->url,
735                                 ),
736                             null);
737                 }
738             }
739
740             if (!empty($this->geopoint)) {
741                 $xo->element(
742                     'georss:point',
743                     null,
744                     $this->geopoint
745                 );
746             }
747
748             if (!empty($this->poco)) {
749                 $this->poco->outputTo($xo);
750             }
751
752             // @fixme there's no way here to make a tree; elements can only contain plaintext
753             // @fixme these may collide with JSON extensions
754             foreach ($this->extra as $el) {
755                 list($extraTag, $attrs, $content) = array_pad($el, 3, null);
756                 $xo->element($extraTag, $attrs, $content);
757             }
758
759             Event::handle('EndActivityObjectOutputAtom', array($this, $xo));
760         }
761
762         if (!empty($tag)) {
763             $xo->elementEnd($tag);
764         }
765
766         return;
767     }
768
769     function asString($tag='activity:object')
770     {
771         $xs = new XMLStringer(true);
772
773         $this->outputTo($xs, $tag);
774
775         return $xs->getString();
776     }
777
778     /*
779      * Returns an array based on this Activity Object suitable for
780      * encoding as JSON.
781      *
782      * @return array $object the activity object array
783      */
784
785     function asArray()
786     {
787         $object = array();
788
789         if (Event::handle('StartActivityObjectOutputJson', array($this, &$object))) {
790             // XXX: attachments are added by Activity
791
792             // author (Add object for author? Could be useful for repeats.)
793
794             // content (Add rendered version of the notice?)
795
796             // downstreamDuplicates
797
798             // id
799
800             if ($this->id) {
801                 $object['id'] = $this->id;
802             } else if ($this->link) {
803                 $object['id'] = $this->link;
804             }
805
806             if ($this->type == ActivityObject::PERSON
807                 || $this->type == ActivityObject::GROUP) {
808
809                 // displayName
810                 $object['displayName'] = $this->title;
811
812                 // XXX: Not sure what the best avatar is to use for the
813                 // author's "image". For now, I'm using the large size.
814
815                 $imgLink          = null;
816                 $avatarMediaLinks = array();
817
818                 foreach ($this->avatarLinks as $a) {
819
820                     // Make a MediaLink for every other Avatar
821                     $avatar = new ActivityStreamsMediaLink(
822                         $a->url,
823                         $a->width,
824                         $a->height,
825                         $a->type,
826                         'avatar'
827                     );
828
829                     // Find the big avatar to use as the "image"
830                     if ($a->height == AVATAR_PROFILE_SIZE) {
831                         $imgLink = $avatar;
832                     }
833
834                     $avatarMediaLinks[] = $avatar->asArray();
835                 }
836
837                 if (!array_key_exists('status_net', $object)) {
838                     $object['status_net'] = array();
839                 }
840
841                 $object['status_net']['avatarLinks'] = $avatarMediaLinks; // extension
842
843                 // image
844                 if (!empty($imgLink)) {
845                     $object['image']  = $imgLink->asArray();
846                 }
847             }
848
849             // objectType
850             //
851             // We can probably use the whole schema URL here but probably the
852             // relative simple name is easier to parse
853
854             $object['objectType'] = ActivityObject::canonicalType($this->type);
855
856             // summary
857             $object['summary'] = $this->summary;
858
859             // content, usually rendered HTML
860             $object['content'] = $this->content;
861
862             // published (probably don't need. Might be useful for repeats.)
863
864             // updated (probably don't need this)
865
866             // TODO: upstreamDuplicates
867
868             if ($this->link) {
869                 $object['url'] = $this->link;
870             }
871
872             /* Extensions */
873             // @fixme these may collide with XML extensions
874             // @fixme multiple tags of same name will overwrite each other
875             // @fixme text content from XML extensions will be lost
876
877             foreach ($this->extra as $e) {
878                 list($objectName, $props, $txt) = array_pad($e, 3, null);
879                 if (!empty($objectName)) {
880                     $parts = explode(":", $objectName);
881                     if (count($parts) == 2 && $parts[0] == "statusnet") {
882                         if (!array_key_exists('status_net', $object)) {
883                             $object['status_net'] = array();
884                         }
885                         $object['status_net'][$parts[1]] = $props;
886                     } else {
887                         $object[$objectName] = $props;
888                     }
889                 }
890             }
891
892             if (!empty($this->geopoint)) {
893
894                 list($lat, $lon) = explode(' ', $this->geopoint);
895
896                 if (!empty($lat) && !empty($lon)) {
897                     $object['location'] = array(
898                         'objectType' => 'place',
899                         'position' => sprintf("%+02.5F%+03.5F/", $lat, $lon),
900                         'lat' => $lat,
901                         'lon' => $lon
902                     );
903
904                     $loc = Location::fromLatLon((float)$lat, (float)$lon);
905
906                     if ($loc) {
907                         $name = $loc->getName();
908
909                         if ($name) {
910                             $object['location']['displayName'] = $name;
911                         }
912                         $url = $loc->getURL();
913
914                         if ($url) {
915                             $object['location']['url'] = $url;
916                         }
917                     }
918                 }
919             }
920
921             if (!empty($this->poco)) {
922                 $object['portablecontacts_net'] = array_filter($this->poco->asArray());
923             }
924
925             if (!empty($this->thumbnail)) {
926                 if (is_string($this->thumbnail)) {
927                     $object['image'] = array('url' => $this->thumbnail);
928                 } else {
929                     $object['image'] = array('url' => $this->thumbnail->url);
930                     if ($this->thumbnail->width) {
931                         $object['image']['width'] = $this->thumbnail->width;
932                     }
933                     if ($this->thumbnail->height) {
934                         $object['image']['height'] = $this->thumbnail->height;
935                     }
936                 }
937             }
938
939             switch (ActivityObject::canonicalType($this->type)) {
940             case 'image':
941                 if (!empty($this->largerImage)) {
942                     $object['fullImage'] = array('url' => $this->largerImage);
943                 }
944                 break;
945             case 'audio':
946             case 'video':
947                 if (!empty($this->stream)) {
948                     $object['stream'] = array('url' => $this->stream);
949                 }
950                 break;
951             }
952
953             Event::handle('EndActivityObjectOutputJson', array($this, &$object));
954         }
955         return array_filter($object);
956     }
957
958     static function canonicalType($type) {
959         $ns = 'http://activitystrea.ms/schema/1.0/';
960         if (substr($type, 0, mb_strlen($ns)) == $ns) {
961             return substr($type, mb_strlen($ns));
962         } else {
963             return $type;
964         }
965     }
966
967     static function mimeTypeToObjectType($mimeType) {
968         $ot = null;
969
970         // Default
971
972         if (empty($mimeType)) {
973             return self::FILE;
974         }
975
976         $parts = explode('/', $mimeType);
977
978         switch ($parts[0]) {
979         case 'image':
980             $ot = self::IMAGE;
981             break;
982         case 'audio':
983             $ot = self::AUDIO;
984             break;
985         case 'video':
986             $ot = self::VIDEO;
987             break;
988         default:
989             $ot = self::FILE;
990         }
991
992         return $ot;
993     }
994 }