banana/spool.inc.php

   1 <?php
   2 /********************************************************************************
   3 * include/spool.inc.php : spool subroutines
   4 * -----------------------
   5 *
   6 * This file is part of the banana distribution
   7 * Copyright: See COPYING files that comes with this distribution
   8 ********************************************************************************/
   9
  10 require_once dirname(__FILE__) . '/banana.inc.php';
  11
  12 define('BANANA_SPOOL_VERSION', '0.5');
  13
  14 /** Class spoolhead
  15  *  class used in thread overviews
  16  */
  17 class BananaSpoolHead
  18 {
  19     /** date (timestamp) */
  20     public $date;
  21     /** subject */
  22     public $subject;
  23     /** author */
  24     public $from;
  25     /** reference of parent */
  26     public $parent = null;
  27     /** paren is direct */
  28     public $parent_direct;
  29     /** array of children */
  30     public $children = Array();
  31     /** true if post is read */
  32     public $isread;
  33     /** number of posts deeper in this branch of tree */
  34     public $desc;
  35     /**  same as desc, but counts only unread posts */
  36     public $descunread;
  37
  38     /** storage data */
  39     public $storage = array();
  40
  41     /** constructor
  42      * @param $_date INTEGER timestamp of post
  43      * @param $_subject STRING subject of post
  44      * @param $_from STRING author of post
  45      * @param $_desc INTEGER desc value (1 for a new post)
  46      * @param $_read BOOLEAN true if read
  47      * @param $_descunread INTEGER descunread value (0 for a new post)
  48      */
  49     public function __construct(array &$message)
  50     {
  51         $this->date       = $message['date'];
  52         $this->subject    = $message['subject'];
  53         $this->from       = $message['from'];
  54         $this->desc       = 1;
  55         $this->isread     = true;
  56         $this->descunread = 0;
  57     }
  58 }
  59
  60
  61 class BananaSpool
  62 {
  63     private $version;
  64     private $mode;
  65
  66     /**  group name */
  67     public $group;
  68     /**  spool */
  69     public $overview;
  70     /**  array msgid => msgnum */
  71     public $ids;
  72     /** thread starts */
  73     public $roots;
  74     /** protocole specific data */
  75     public $storage = array();
  76
  77     private $unreadnb = 0;
  78
  79     /** constructor
  80      * @param $_group STRING group name
  81      * @param $_display INTEGER 1 => all posts, 2 => only threads with new posts
  82      * @param $_since INTEGER time stamp (used for read/unread)
  83      */
  84     protected function __construct($group)
  85     {
  86         $this->version    = BANANA_SPOOL_VERSION;
  87         $this->mode       = Banana::SPOOL_ALL;
  88         $this->group      = $group;
  89     }
  90
  91     public static function &getSpool($group, $since = 0, $clean = false)
  92     {
  93         if (!is_null(Banana::$spool) && Banana::$spool->group == $group) {
  94             $spool =& Banana::$spool;
  95         } else {
  96             $spool =& BananaSpool::readFromFile($group);
  97         }
  98         if (is_null($spool)) {
  99             $spool = new BananaSpool($group);
 100         }
 101         Banana::$spool =& $spool;
 102         $spool->build();
 103         if ($clean) {
 104             $spool->markAllAsRead();
 105         }
 106         $spool->updateUnread($since);
 107         return $spool;
 108     }
 109
 110     private static function spoolFilename($group)
 111     {
 112         $file = Banana::$spool_root . '/' . Banana::$protocole->name() . '/';
 113         if (!is_dir($file)) {
 114             mkdir($file);
 115         }
 116         return $file . Banana::$protocole->filename();
 117     }
 118
 119     private static function &readFromFile($group)
 120     {
 121         $spool = null;
 122         $file = BananaSpool::spoolFilename($group);
 123         if (!file_exists($file)) {
 124             return $spool;
 125         }
 126         $spool =  unserialize(file_get_contents($file));
 127         if ($spool->version != BANANA_SPOOL_VERSION || $spool->mode != Banana::SPOOL_ALL) {
 128             $spool = null;
 129             return $spool;
 130         }
 131         $spool->markAllAsRead();
 132         return $spool;
 133     }
 134
 135     private function compare($a, $b)
 136     {
 137         return ($this->overview[$b]->date >= $this->overview[$a]->date);
 138     }
 139
 140     private function saveToFile()
 141     {
 142         $file = BananaSpool::spoolFilename($this->group);
 143
 144         $this->roots = Array();
 145         foreach($this->overview as $id=>&$msg) {
 146             if (is_null($msg->parent)) {
 147                 $this->roots[] = $id;
 148             }
 149         }
 150         usort($this->roots, array($this, 'compare'));
 151
 152         if ($this->mode == Banana::SPOOL_ALL) {
 153             file_put_contents($file, serialize($this));
 154         }
 155     }
 156
 157     private function build()
 158     {
 159         $threshold = 0;
 160
 161         // Compute the range of indexes
 162         list($msgnum, $first, $last) = Banana::$protocole->getIndexes();
 163         if ($last < $first) {
 164             $threshold = $first + $msgnum - $last;
 165             $threshold = (int)(log($threshold)/log(2));
 166             $threshold = (2 ^ ($threshold + 1)) - 1;
 167         }
 168         if (Banana::$spool_max && Banana::$spool_max < $msgnum) {
 169             $first = $last - Banana::$spool_max;
 170             if ($first < 0) {
 171                 $first += $threshold;
 172             }
 173         }
 174         $clean  = $this->clean($first, $last, $msgnum);
 175         $update = $this->update($first, $last, $msgnum);
 176
 177         if ($clean || $update) {
 178             $this->saveToFile();
 179         }
 180     }
 181
 182     private function clean(&$first, &$last, $msgnum)
 183     {
 184         $do_save = false;
 185         if (is_array($this->overview)) {
 186             $mids = array_keys($this->overview);
 187             foreach ($mids as $id) {
 188                 if (($first <= $last && ($id < $first || $id > $last))
 189                         || ($first > $last && $id < $first && $id > $last)) {
 190                     $this->delid($id, false);
 191                     $do_save = true;
 192                 }
 193             }
 194             if (!empty($this->overview)) {
 195                 $first = max(array_keys($this->overview))+1;
 196             }
 197         }
 198         return $do_save;
 199     }
 200
 201     private function update(&$first, &$last, $msgnum)
 202     {
 203         if ($first > $last || !$msgnum) {
 204             return false;
 205         }
 206
 207         $messages =& Banana::$protocole->getMessageHeaders($first, $last,
 208             array('Date', 'Subject', 'From', 'Message-ID', 'References', 'In-Reply-To'));
 209
 210         if (!is_array($this->ids)) {
 211             $this->ids = array();
 212         }
 213         foreach ($messages as $id=>&$message) {
 214             $this->ids[$message['message-id']] = $id;
 215         }
 216
 217         if (!is_array($this->overview)) {
 218             $this->overview = array();
 219         }
 220         foreach ($messages as $id=>&$message) {
 221             if (!isset($this->overview[$id])) {
 222                 $this->overview[$id] = new BananaSpoolHead($message);
 223             }
 224             $msg    =& $this->overview[$id];
 225             $msgrefs = BananaMessage::formatReferences($message);
 226             $parents = preg_grep('/^\d+$/', $msgrefs);
 227             $msg->parent = array_pop($parents);
 228             $msg->parent_direct = preg_match('/^\d+$/', array_pop($msgrefs));
 229
 230             if (!is_null($p = $msg->parent)) {
 231                 if (empty($this->overview[$p])) {
 232                     $this->overview[$p] = new BananaSpoolHead($messages[$p]);
 233                 }
 234                 $this->overview[$p]->children[] = $id;
 235
 236                 while (!is_null($p)) {
 237                     $this->overview[$p]->desc += $msg->desc;
 238                     if ($p != $this->overview[$p]->parent) {
 239                         $p = $this->overview[$p]->parent;
 240                     } else {
 241                         $p = null;
 242                     }
 243                 }
 244             }
 245         }
 246         Banana::$protocole->updateSpool($messages);
 247         return true;
 248     }
 249
 250     public function updateUnread($since)
 251     {
 252         if (empty($since)) {
 253             return;
 254         }
 255
 256         $newpostsids = Banana::$protocole->getNewIndexes($since);
 257
 258         if (empty($newpostsids)) {
 259             return;
 260         }
 261
 262         if (!is_array($this->ids)) {
 263             $this->ids = array();
 264         }
 265         $newpostsids = array_intersect($newpostsids, array_keys($this->ids));
 266         foreach ($newpostsids as $mid) {
 267             $id = $this->ids[$mid];
 268             if ($this->overview[$id]->isread) {
 269                 $this->overview[$id]->isread = false;
 270                 $this->unreadnb++;
 271                 while (isset($id)) {
 272                     $this->overview[$id]->descunread++;
 273                     $id = $this->overview[$id]->parent;
 274                 }
 275             }
 276         }
 277     }
 278
 279     public function setMode($mode)
 280     {
 281         $this->mode = $mode;
 282         switch ($mode) {
 283           case Banana::SPOOL_UNREAD:
 284             $num = max(array_keys($this->overview));
 285             if ($this->overview[$num]->isread) {
 286                 break;
 287             }
 288             foreach ($this->roots as $k=>$i) {
 289                 if ($this->overview[$i]->descunread == 0) {
 290                     $this->killdesc($i);
 291                     unset($this->roots[$k]);
 292                 }
 293             }
 294             break;
 295         }
 296     }
 297
 298     /** Mark the given id as read
 299      * @param id MSGNUM of post
 300      */
 301     public function markAsRead($id)
 302     {
 303         if (!$this->overview[$id]->isread) {
 304             $this->overview[$id]->isread = true;
 305             $this->unreadnb--;
 306             while (isset($id)) {
 307                 $this->overview[$id]->descunread--;
 308                 $id = $this->overview[$id]->parent;
 309             }
 310         }
 311     }
 312
 313     /** Mark all unread messages as read
 314      */
 315     public function markAllAsRead(array &$array = null)
 316     {
 317         if (!$this->unreadnb) {
 318             return;
 319         }
 320         if (is_null($array) && is_array($this->roots)) {
 321             $array =& $this->roots;
 322         } elseif (is_null($array)) {
 323             return;
 324         }
 325         foreach ($array as $id) {
 326             if (!$this->overview[$id]->isread) {
 327                 $this->markAsRead($id);
 328                 if (!$this->unreadnb) {
 329                     return;
 330                 }
 331             }
 332             if ($this->overview[$id]->descunread) {
 333                 $this->markAllAsRead($this->overview[$id]->children);
 334             }
 335         }
 336     }
 337
 338     /** kill post and childrens
 339      * @param $_id MSGNUM of post
 340      */
 341     private function killdesc($_id)
 342     {
 343         if (sizeof($this->overview[$_id]->children)) {
 344             foreach ($this->overview[$_id]->children as $c) {
 345                 $this->killdesc($c);
 346             }
 347         }
 348         unset($this->overview[$_id]);
 349         if (($msgid = array_search($_id, $this->ids)) !== false) {
 350             unset($this->ids[$msgid]);
 351         }
 352     }
 353
 354     /** delete a post from overview
 355      * @param $_id MSGNUM of post
 356      */
 357     public function delid($_id, $write = true)
 358     {
 359         if (isset($this->overview[$_id])) {
 360             $overview =& $this->overview[$_id];
 361             if (!$overview->isread) {
 362                 $this->markAsRead($_id);
 363             }
 364             if ($overview->parent) {
 365                 $p      =  $overview->parent;
 366                 $parent =& $this->overview[$p];
 367                 $parent->children = array_diff($parent->children, array($_id));
 368                 if (sizeof($overview->children)) {
 369                     $parent->children = array_merge($parent->children, $overview->children);
 370                     foreach ($overview->children as $c) {
 371                         $this->overview[$c]->parent        = $p;
 372                         $this->overview[$c]->parent_direct = false;
 373                     }
 374                 }
 375                 while (isset($p)) {
 376                     $this->overview[$p]->desc--;
 377                     $p = $this->overview[$p]->parent;
 378                 }
 379             } elseif ($overview->children) {
 380                 foreach ($overview->children as $c) {
 381                     $this->overview[$c]->parent = null;
 382                 }
 383             }
 384             unset($overview);
 385             unset($this->overview[$_id]);
 386             $msgid = array_search($_id, $this->ids);
 387             if ($msgid !== false) {
 388                 unset($this->ids[$msgid]);
 389             }
 390             $msgid = array_search($_id, $this->roots);
 391             if ($msgid !== false) {
 392                 unset($this->roots[$msgid]);
 393             }
 394
 395             if ($write) {
 396                 $this->saveToFile();
 397             }
 398         }
 399     }
 400
 401     private function formatDate($stamp)
 402     {
 403         $today  = intval(time() / (24*3600));
 404         $dday   = intval($stamp / (24*3600));
 405
 406         if ($today == $dday) {
 407             $format = "%H:%M";
 408         } elseif ($today == 1 + $dday) {
 409             $format = _b_('hier')." %H:%M";
 410         } elseif ($today < 7 + $dday) {
 411             $format = '%a %H:%M';
 412         } elseif ($today < 90 + $dday) {
 413             $format = '%a %e %b';
 414         } else {
 415             $format = '%a %e %b %Y';
 416         }
 417         return strftime($format, $stamp);
 418     }
 419
 420     /** displays children tree of a post
 421      * @param $_id INTEGER MSGNUM of post
 422      * @param $_index INTEGER linear number of post in the tree
 423      * @param $_first INTEGER linear number of first post displayed
 424      * @param $_last INTEGER linear number of last post displayed
 425      * @param $_ref STRING MSGNUM of current post
 426      * @param $_pfx_node STRING prefix used for current node
 427      * @param $_pfx_end STRING prefix used for children of current node
 428      * @param $_head BOOLEAN true if first post in thread
 429      *
 430      * If you want to analyse subject, you can define the function hook_formatDisplayHeader
 431      */
 432     private function _to_html($_id, $_index, $_first=0, $_last=0, $_ref="", $_pfx_node="", $_pfx_end="", $_head=true, $_pfx_id="")
 433     {
 434         static $spfx_f, $spfx_n, $spfx_Tnd, $spfx_Lnd, $spfx_snd, $spfx_T, $spfx_L, $spfx_s, $spfx_e, $spfx_I;
 435         if (!isset($spfx_f)) {
 436             $spfx_f   = Banana::$page->makeImg(Array('img' => 'k1',       'alt' => 'o', 'height' => 21,  'width' => 9));
 437             $spfx_n   = Banana::$page->makeImg(Array('img' => 'k2',       'alt' => '*', 'height' => 21,  'width' => 9));
 438             $spfx_Tnd = Banana::$page->makeImg(Array('img' => 'T-direct', 'alt' => '+', 'height' => 21, 'width' => 12));
 439             $spfx_Lnd = Banana::$page->makeImg(Array('img' => 'L-direct', 'alt' => '`', 'height' => 21, 'width' => 12));
 440             $spfx_snd = Banana::$page->makeImg(Array('img' => 's-direct', 'alt' => '-', 'height' => 21, 'width' => 5));
 441             $spfx_T   = Banana::$page->makeImg(Array('img' => 'T',        'alt' => '+', 'height' => 21, 'width' => 12));
 442             $spfx_L   = Banana::$page->makeImg(Array('img' => 'L',        'alt' => '`', 'height' => 21, 'width' => 12));
 443             $spfx_s   = Banana::$page->makeImg(Array('img' => 's',        'alt' => '-', 'height' => 21, 'width' => 5));
 444             $spfx_e   = Banana::$page->makeImg(Array('img' => 'e',   'alt' => '&nbsp;', 'height' => 21, 'width' => 12));
 445             $spfx_I   = Banana::$page->makeImg(Array('img' => 'I',        'alt' => '|', 'height' => 21, 'width' => 12));
 446         }
 447
 448         $overview =& $this->overview[$_id];
 449         if ($_index + $overview->desc < $_first || $_index > $_last) {
 450             return '';
 451         }
 452
 453         $res = '';
 454         if ($_index >= $_first) {
 455             $hc = empty($overview->children);
 456
 457             $res .= '<tr id="'.$_pfx_id.$_id.'" class="' . ($_index%2 ? 'pair' : 'impair') . ($overview->isread ? '' : ' new') . "\">\n";
 458             $res .= '<td class="date">' . $this->formatDate($overview->date) . " </td>\n";
 459             $res .= '<td class="subj' . ($_index == $_ref ? ' cur' : '') . '"><div class="tree">'
 460                 . $_pfx_node .($hc ? ($_head ? $spfx_f : ($overview->parent_direct ? $spfx_s : $spfx_snd)) : $spfx_n)
 461                 . '</div>';
 462             $popup = $subject = $overview->subject;
 463             if (function_exists('hook_formatDisplayHeader')) {
 464                 list($subject, $link) = hook_formatDisplayHeader('subject', $subject, true);
 465             } else {
 466                 $subject = banana_catchFormats(banana_entities(stripslashes($subject)));
 467                 $link = null;
 468             }
 469             if (empty($subject)) {
 470                 $subject = _b_('(pas de sujet)');
 471             }
 472             if ($_index != $_ref) {
 473                 $subject = Banana::$page->makeLink(Array('group' => $this->group, 'artid' => $_id,
 474                                                     'text'  => $subject, 'popup' => $popup));
 475             }
 476             $res .= '&nbsp;' . $subject . $link;
 477             $res .= "</td>\n<td class='from'>" . BananaMessage::formatFrom($overview->from) . "</td>\n</tr>";
 478
 479             if ($hc) {
 480                 return $res;
 481             }
 482         }
 483
 484         $_index ++;
 485         $children = $overview->children;
 486         while ($child = array_shift($children)) {
 487             $overview =& $this->overview[$child];
 488             if ($_index > $_last) {
 489                 return $res;
 490             }
 491             if ($_index + $overview->desc >= $_first) {
 492                 if (sizeof($children)) {
 493                     $res .= $this->_to_html($child, $_index, $_first, $_last, $_ref,
 494                             $_pfx_end . ($overview->parent_direct ? $spfx_T : $spfx_Tnd),
 495                             $_pfx_end . $spfx_I, false,$_id.'_');
 496                 } else {
 497                     $res .= $this->_to_html($child, $_index, $_first, $_last, $_ref,
 498                             $_pfx_end . ($overview->parent_direct ? $spfx_L : $spfx_Lnd),
 499                             $_pfx_end . $spfx_e, false,$_id.'_');
 500                 }
 501             }
 502             $_index += $overview->desc;
 503         }
 504
 505         return $res;
 506     }
 507
 508     /** Displays overview
 509      * @param $_first INTEGER MSGNUM of first post
 510      * @param $_last INTEGER MSGNUM of last post
 511      * @param $_ref STRING MSGNUM of current/selectionned post
 512      */
 513     public function toHtml($first = 0, $overview = false)
 514     {
 515         $res = Banana::$page->makeJs('jquery');
 516         $res .= Banana::$page->makeJs('spool_toggle');
 517
 518         if (!$overview) {
 519             $_first = $first;
 520             $_last  = $first + Banana::$spool_tmax - 1;
 521             $_ref   = null;
 522         } else {
 523             $_ref   = $this->getNdx($first);
 524             $_last  = $_ref + Banana::$spool_tafter;
 525             $_first = $_ref - Banana::$spool_tbefore;
 526             if ($_first < 0) {
 527                 $_last -= $_first;
 528             }
 529         }
 530         $index = 1;
 531         foreach ($this->roots as $id) {
 532             $res   .= $this->_to_html($id, $index, $_first, $_last, $_ref);
 533             $index += $this->overview[$id]->desc ;
 534             if ($index > $_last) {
 535                 break;
 536             }
 537         }
 538         return $res;
 539     }
 540
 541     /** computes linear post index
 542      * @param $_id INTEGER MSGNUM of post
 543      * @return INTEGER linear index of post
 544      */
 545     public function getNdX($_id)
 546     {
 547         $ndx    = 1;
 548         $id_cur = $_id;
 549         while (true) {
 550             $id_parent = $this->overview[$id_cur]->parent;
 551             if (is_null($id_parent)) break;
 552             $pos       = array_search($id_cur, $this->overview[$id_parent]->children);
 553
 554             for ($i = 0; $i < $pos ; $i++) {
 555                 $ndx += $this->overview[$this->overview[$id_parent]->children[$i]]->desc;
 556             }
 557             $ndx++; //noeud père
 558
 559             $id_cur = $id_parent;
 560         }
 561
 562         foreach ($this->roots as $i) {
 563             if ($i==$id_cur) {
 564                 break;
 565             }
 566             $ndx += $this->overview[$i]->desc;
 567         }
 568         return $ndx;
 569     }
 570
 571     /** Return root message of the given thread
 572      * @param id INTEGER id of a message
 573      */
 574     public function root($id)
 575     {
 576         $id_cur = $id;
 577         while (true) {
 578             $id_parent = $this->overview[$id_cur]->parent;
 579             if (is_null($id_parent)) break;
 580             $id_cur = $id_parent;
 581         }
 582         return $id_cur;
 583     }
 584
 585     /** Return the last post id with the given subject
 586      * @param subject
 587      */
 588     public function getPostId($subject)
 589     {
 590         $subject = trim($subject);
 591         $id = max(array_keys($this->overview));
 592         while (isset($this->overview[$id])) {
 593             $test = $this->overview[$id]->subject;
 594             if (function_exists('hook_formatDisplayHeader')) {
 595                 $val = hook_formatDisplayHeader('subject', $test, true);
 596                 if (is_array($val)) {
 597                     $test = banana_html_entity_decode($val[0]);
 598                 } else {
 599                     $test = banana_html_entity_decode($val);
 600                 }
 601             }
 602             $test = trim($test);
 603             if ($test == $subject) {
 604                 return $id;
 605             }
 606             $id--;
 607         }
 608         return -1;
 609     }
 610
 611     /** Returns previous thread root index
 612      * @param id INTEGER message number
 613      */
 614     public function prevThread($id)
 615     {
 616         $root = $this->root($id);
 617         $last = null;
 618         foreach ($this->roots as $i) {
 619             if ($i == $root) {
 620                 return $last;
 621             }
 622             $last = $i;
 623         }
 624         return $last;
 625     }
 626
 627     /** Returns next thread root index
 628      * @param id INTEGER message number
 629      */
 630     public function nextThread($id)
 631     {
 632         $root = $this->root($id);
 633         $ok   = false;
 634         foreach ($this->roots as $i) {
 635             if ($ok) {
 636                 return $i;
 637             }
 638             if ($i == $root) {
 639                 $ok = true;
 640             }
 641         }
 642         return null;
 643     }
 644
 645     /** Return prev post in the thread
 646      * @param id INTEGER message number
 647      */
 648     public function prevPost($id)
 649     {
 650         $parent = $this->overview[$id]->parent;
 651         if (is_null($parent)) {
 652             return null;
 653         }
 654         $last = $parent;
 655         foreach ($this->overview[$parent]->children as $child) {
 656             if ($child == $id) {
 657                 return $last;
 658             }
 659             $last = $child;
 660         }
 661         return null;
 662     }
 663
 664     /** Return next post in the thread
 665      * @param id INTEGER message number
 666      */
 667     public function nextPost($id)
 668     {
 669         if (count($this->overview[$id]->children) != 0) {
 670             return $this->overview[$id]->children[0];
 671         }
 672
 673         $cur    = $id;
 674         while (true) {
 675             $parent = $this->overview[$cur]->parent;
 676             if (is_null($parent)) {
 677                 return null;
 678             }
 679             $ok = false;
 680             foreach ($this->overview[$parent]->children as $child) {
 681                 if ($ok) {
 682                     return $child;
 683                 }
 684                 if ($child == $cur) {
 685                     $ok = true;
 686                 }
 687             }
 688             $cur = $parent;
 689         }
 690         return null;
 691     }
 692
 693     /** Look for an unread message in the thread rooted by the message
 694      * @param id INTEGER message number
 695      */
 696     private function _nextUnread($id)
 697     {
 698         if (!$this->overview[$id]->isread) {
 699             return $id;
 700         }
 701         foreach ($this->overview[$id]->children as $child) {
 702             $unread = $this->_nextUnread($child);
 703             if (!is_null($unread)) {
 704                 return $unread;
 705             }
 706         }
 707         return null;
 708     }
 709
 710     /** Find next unread message
 711      * @param id INTEGER message number
 712      */
 713     public function nextUnread($id = null)
 714     {
 715         if (!$this->unreadnb) {
 716             return null;
 717         }
 718
 719         if (!is_null($id)) {
 720             // Look in message children
 721             foreach ($this->overview[$id]->children as $child) {
 722                 $next = $this->_nextUnread($child);
 723                 if (!is_null($next)) {
 724                     return $next;
 725                 }
 726             }
 727         }
 728
 729         // Look in current thread
 730         $cur = $id;
 731         do {
 732             $parent = is_null($cur) ? null : $this->overview[$cur]->parent;
 733             $ok     = is_null($cur) ? true : false;
 734             if (!is_null($parent)) {
 735                 $array = &$this->overview[$parent]->children;
 736             } else {
 737                 $array = &$this->roots;
 738             }
 739             foreach ($array as $child) {
 740                 if ($ok) {
 741                     $next = $this->_nextUnread($child);
 742                     if (!is_null($next)) {
 743                         return $next;
 744                     }
 745                 }
 746                 if ($child == $cur) {
 747                     $ok = true;
 748                 }
 749             }
 750             $cur = $parent;
 751         } while(!is_null($cur));
 752         return null;
 753     }
 754 }
 755
 756 // vim:set et sw=4 sts=4 ts=4 enc=utf-8:
 757 ?>