/**
* Get a selection of flashcards for review, as an array of flashcard ids.
*
* Orders flashcards by expiredate (longest expired first), and then
* randomize cards that expire on the same date.
*
* Only works for current user (sqlLocalTime).
*
* @param mixed $box 'all' or a Leitner box number starting from 1
* @param string $type 'expired', 'untested', 'relearned', anything else means 'fresh' (non-expired)
* @param string $filt 'rtk1', 'rkt3', '' for all kanji
* @param boolean $merge True to merge flashcards from given box with higher boxes
*
* @return array Flashcard ids (framenum).
*/
public static function getFlashcards($box, $type, $filt, $merge)
{
$user = coreContext::getInstance()->getUser();
$userId = $user->getUserId();
$sqlLocalTime = new coreDbExpr($user->sqlLocalTime());
if ($type === 'relearned') {
// select cards from relearned kanji selection
$select = LearnedKanjiPeer::getInstance()->select('framenum');
$select->where('userid = ?', $userId);
} else {
$select = self::getInstance()->select('framenum');
$select = self::filterByUserId($select, $userId);
$select = self::filterByRtk($select, $filt);
}
switch ($type) {
case 'untested':
$select->where('totalreviews = 0');
$select->order('expiredate, RAND()');
break;
case 'relearned':
$select->order('RAND()');
break;
default:
// expired or non-expired (orange or green stacks)
if ($type == 'expired') {
$select->where('totalreviews > 0 AND expiredate <= ?', $sqlLocalTime);
} else {
$select->where('totalreviews > 0 AND expiredate > ?', $sqlLocalTime);
}
if ($box == 'all') {
$select->where('leitnerbox > 1');
} elseif ($merge) {
$select->where('leitnerbox >= ?', $box);
} else {
$select->where('leitnerbox = ?', $box);
}
$select->order('expiredate, RAND()');
break;
}
//DBG::out($select);exit;
return self::$db->fetchCol($select);
}