sequencinglib.php

很棒的在线教学系统

		            return $seq;
				}
			}
		}
		break;
	}

	if (array_search ($ancestors, $comancestor)!== false){
		$ancestorscurrent = scorm_get_ancestors($seq->currentactivity);
		$commonpos = scorm_find_common_ancestor($ancestors,$sco);
		$curcommon = array_slice($ancestorscurrent,0,$commonpos-1);
		if(empty($curcommon)){
			$seq->delivery = null;
		    $seq->exception = 'SB.2.9-5';
		    return $seq;
		}

		$constrained = null;
		foreach ($curcommon as $acti){
			$acti = scorm_get_sco($acti->id);
			if ( isset($acti->choiceexit) && ($acti->choiceexit == false)){
					$seq->delivery = null;
		            $seq->exception = 'SB.2.9-7';
		            return $seq;
			}
			if ($constrained == null){
				if($acti->constrainchoice == true){
					$constrained = $acti;
				}
			}
		}
		if ($constrained != null){
            $fwdir = scorm_get_preorder($constrained);

		    if(array_search ($fwdir, $sco)!== false){
				$traverse = 'forward';
			}
			else{
				$traverse = 'backward';
			}
			$seq = scorm_seq_choice_flow ($constrained, $traverse, $seq);
			$actconsider = $seq->identifiedactivity;
			$avdescendents = Array();
			$avdescendents= scorm_get_available_descendents ($actconsider);
			if (array_search ($avdescendents, $sco) !== false && $sco->id != $actconsider->id && $constrained->id != $sco->id ){
				$seq->delivery = null;
		        $seq->exception = 'SB.2.9-8';
		        return $seq;
			}

//CONTINUE 11.5.5
		}

		$commonpos = scorm_find_common_ancestor($ancestors,$seq->currentactivity);
		$comtarget = array_slice($ancestors, 1,$commonpos-1);//path from the common ancestor to the target activity
		$comtarget = array_reverse($comtarget);

		if (empty($comtarget)){
			$seq->delivery = null;
		    $seq->exception = 'SB.2.9-5';
		    return $seq;
		}

		$fwdir = scorm_get_preorder($seq->currentactivity);

		if(array_search ($fwdir, $sco)!== false){

		    foreach ($comtarget as $act){
			    $seq = scorm_seq_choice_activity_traversal($act,$userid,$seq,'forward');
		        if(!$seq->reachable){
			        $seq->delivery = null;
			        return $seq;
		        }
                $act = scorm_get_sco($act->id);
			    if(scorm_seq_is('active',$act->id,$userid) && ($act->id != $comancestor->id && ($act->preventactivation == true))){
				    $seq->delivery = null;
		            $seq->exception = 'SB.2.9-6';
		            return $seq;
			    }
		    }

		}
		else{
			foreach ($comtarget as $act){
				$act = scorm_get_sco($act->id);
			    if(scorm_seq_is('active',$act->id,$userid) && ($act->id != $comancestor->id && ($act->preventactivation==true))){
				    $seq->delivery = null;
		            $seq->exception = 'SB.2.9-6';
		            return $seq;
			    }
		    }
		}
	    break;	
	}

	if(scorm_is_leaf ($sco)){
		$seq->delivery = $sco;
		$seq->exception = 'SB.2.9-6';
		return $seq;
	}

    $seq = scorm_seq_flow ($sco,'forward',$seq,true,$userid);
    if ($seq->deliverable == false){
		scorm_terminate_descendent_attempts($comancestor,$userid,$seq);
		scorm_seq_end_attempt($comancestor,$userid,$seq->attempt);
		$seq->currentactivity = $sco;
		$seq->delivery = null;
		$seq->exception = 'SB.2.9-9';
		return $seq;

	}
	else{
		return $seq;
	}
  
}

function scorm_seq_choice_flow ($constrained, $traverse, $seq){
	$seq = scorm_seq_choice_flow_tree ($constrained, $traverse, $seq);
	if ($seq->identifiedactivity == null){
        $seq->identifiedactivity = $constrained;
		return $seq;
	}
	else{
		return $seq;
	}
}

function scorm_seq_choice_flow_tree ($constrained, $traverse, $seq){
	$islast = false;
	$parent = scorm_get_parent ($constrained);
	if ($traverse== 'forward'){
		$preord = scorm_get_preorder ($constrained);
		if (sizeof($preorder) == 0 || (sizeof($preorder) == 0 && $preorder[0]->id = $constrained->id)){
			$islast = true;//the function is the last activity available
		}
		if ($constrained->parent == '/' || $islast){
			$seq->nextactivity = null;
			return $seq;
		}
		$avchildren = scorm_get_available_children ($parent);//available children
		if ($avchildren [sizeof($avchildren)-1]->id == $constrained->id){
			$seq = scorm_seq_choice_flow_tree ($parent, 'forward', $seq);
			return $seq;
		}
		else{
			$i=0;
			while($i < sizeof($avchildren)){
				if ($avchildren [$i]->id == $constrained->id){
					$seq->nextactivity = $avchildren [$i+1];
					return $seq;
				}
				else{
					$i++;
				}
			}
		}

	}

	if ($traverse== 'backward'){
		if($constrained->parent == '/' ){
			$seq->nextactivity = null;
			return $seq;
		}

		$avchildren = scorm_get_available_children ($parent);//available children
		if ($avchildren [0]->id == $constrained->id){
			$seq = scorm_seq_choice_flow_tree ($parent, 'backward', $seq);
			return $seq;
		}
		else{
			$i=sizeof($avchildren)-1;
			while($i >=0){
				if ($avchildren [$i]->id == $constrained->id){
					$seq->nextactivity = $avchildren [$i-1];
					return $seq;
				}
				else{
					$i--;
				}
			}
		}
	}
}
function scorm_seq_choice_activity_traversal($activity,$userid,$seq,$direction){

	if($direction == 'forward'){

		$act = scorm_seq_rules_check($activity,'stopforwardtraversal');

		if($act != null){
			$seq->reachable = false;
			$seq->exception = 'SB.2.4-1';
		    return $seq;
		}
		$seq->reachable = false;
		return $seq;
	}

	if($direction == 'backward'){
		$parentsco = scorm_get_parent($activity);
		if($parentsco!= null){
			 if (isset($parentsco->forwardonly) && ($parentsco->forwardonly == true)){
				 $seq->reachable = false;
			     $seq->exception = 'SB.2.4-2';
		         return $seq;
			 }
			 else{
			    $seq->reachable = false;
			    $seq->exception = 'SB.2.4-3';
		        return $seq;
		     }
		}
	}
	$seq->reachable = true;
	return $seq;

}

//Delivery Request Process

function scorm_sequencing_delivery($scoid,$userid,$seq){

	if(!scorm_is_leaf ($seq->delivery)){
		$seq->deliveryvalid = false;
		$seq->exception = 'DB.1.1-1';
		return $seq;
	}
	$ancestors = scorm_get_ancestors($seq->delivery);
    $arrpath = array_reverse($ancestors);
	array_push ($arrpath,$seq->delivery);//path from the root to the target

	if (empty($arrpath)){
		$seq->deliveryvalid = false;
		$seq->exception = 'DB.1.1-2';
		return $seq;
	}

	foreach ($arrpath as $activity){
	    if(scorm_check_activity ($activity,$userid)){
		    $seq->deliveryvalid = false;
	        $seq->exception = 'DB.1.1-3';
	        return $seq;
	    }
	}

	$seq->deliveryvalid = true;
	return $seq;

}

function scorm_content_delivery_environment ($seq,$userid){

	$act = $seq->currentactivity;
	if(scorm_seq_is('active',$act->id,$userid)){
		$seq->exception = 'DB.2-1';
	    return $seq;
	}
	$track = get_record('scorm_scoes_track','scoid',$act->id,'userid',$userid,'element','suspendedactivity');
	if ($track != null){
		$seq = scorm_clear_suspended_activity($seq->delivery, $seq);

	}
	$seq = scorm_terminate_descendent_attempts ($seq->delivery,$userid,$seq);
	$ancestors = scorm_get_ancestors($seq->delivery);
    $arrpath = array_reverse($ancestors);
	array_push ($arrpath,$seq->delivery);
	foreach ($arrpath as $activity){
		if(!scorm_seq_is('active',$activity->id,$userid)){
			if(!isset($activity->tracked) || ($activity->tracked == 1)){
				if(!scorm_seq_is('suspended',$activity->id,$userid)){
					$r = get_record('scorm_scoes_track','scoid',$activity->id,'userid',$userid,'element','activityattemptcount');
					$r->value = ($r->value)+1;
					update_record ('scorm_scoes_track',$r);
					if ($r->value == 1){
						scorm_seq_set('activityprogressstatus', $activity->id, $userid, 'true');
					}
					scorm_insert_track($userid, $activity->scorm, $activity->id, 0, 'objectiveprogressstatus', 'false');
					scorm_insert_track($userid, $activity->scorm, $activity->id, 0, 'objectivesatisfiedstatus', 'false');
					scorm_insert_track($userid, $activity->scorm, $activity->id, 0, 'objectivemeasurestatus', 'false');
					scorm_insert_track($userid, $activity->scorm, $activity->id, 0, 'objectivenormalizedmeasure', 0.0);

					scorm_insert_track($userid, $activity->scorm, $activity->id, 0, 'attemptprogressstatus', 'false');
					scorm_insert_track($userid, $activity->scorm, $activity->id, 0, 'attemptcompletionstatus', 'false');
					scorm_insert_track($userid, $activity->scorm, $activity->id, 0, 'attemptabsoluteduration', 0.0);
					scorm_insert_track($userid, $activity->scorm, $activity->id, 0, 'attemptexperiencedduration', 0.0);
					scorm_insert_track($userid, $activity->scorm, $activity->id, 0, 'attemptcompletionamount', 0.0);
				}
			}
            scorm_seq_set('active', $activity->id, $userid, 'true');
		}
	}
	$seq->delivery = $seq->currentactivity;
	scorm_seq_set('suspendedactivity', $activity->id, $userid, 'false');

	//ONCE THE DELIVERY BEGINS (How should I check that?)

    if(isset($activity->tracked) || ($activity->tracked == 0)){
		//How should I track the info and what should I do to not record the information for the activity during delivery? 
		$atabsdur = get_record('scorm_scoes_track','scoid',$activity->id,'userid',$userid,'element','attemptabsoluteduration');
		$atexpdur = get_record('scorm_scoes_track','scoid',$activity->id,'userid',$userid,'element','attemptexperiencedduration');
	}
	return $seq;

 
}
function scorm_clear_suspended_activity($act,$seq){
	$currentact= $seq->currentactivity;
	$track = get_record('scorm_scoes_track','scoid',$currentact->id,'userid',$userid,'element','suspendedactivity');
	if ($track != null){
		$ancestors = scorm_get_ancestors($act);
        $commonpos = scorm_find_common_ancestor($ancestors,$currentact);
        if ($commonpos !== false) {
            if ($activitypath = array_slice($ancestors,0,$commonpos)) {
				if (!empty ($activitypath)){

                    foreach ($activitypath as $activity) {
					    if (scorm_is_leaf($activity)){
							scorm_seq_set('suspended',$activity->id,$userid,false);
						}
						else{
							$children = scorm_get_children($activity);
							$bool= false; 
							foreach ($children as $child){
								if(scorm_seq_is('suspended',$child->id,$userid)){
									$bool= true;
								}
							}
                             if(!$bool){
							    scorm_seq_set('suspended',$activity->id,$userid,false);
							 }
						}
				    }
				}
			}
		}
		scorm_seq_set('suspendedactivity',$act->id,$userid,false);

	}
}

function scorm_select_children_process($scoid,$userid){

	$sco = scorm_get_sco($scoid);
    if (!scorm_is_leaf($sco)){
		if(!scorm_seq_is('suspended',$scoid,$userid) && !scorm_seq_is('active',$scoid,$userid)){
			$r = get_record('scorm_scoes_track','scoid',$scoid,'userid',$userid,'element','selectiontiming');

             switch($r->value) {

                case 'oneachnewattempt':
				case 'never':
                break;
             
                case 'once':
                    if(!scorm_seq_is('activityprogressstatus',$scoid,$userid)){
					    if(scorm_seq_is('selectioncountsstatus',$scoid,$userid)){
					        $childlist = '';
							$res = get_record('scorm_scoes_track','scoid',$scoid,'userid',$userid,'element','selectioncount');
							$i = ($res->value)-1;
							$children = scorm_get_children ($sco);

							while ($i>=0){
								$pos = array_rand($children);
								array_push($childlist,$children [$pos]);
								array_splice($children,$pos,1);
								$i--;
							}
							sort ($childlist);
							$clist = serialize ($childlist);
							scorm_seq_set('availablechildren', $scoid, $userid, false);
							scorm_seq_set('availablechildren', $scoid, $userid, $clist);


				        }
				    }
                break;
               
            }

		}
	}
}

function scorm_randomize_children_process($scoid,$userid){

	$sco = scorm_get_sco($scoid);
    if (!scorm_is_leaf($sco)){
		if(!scorm_seq_is('suspended',$scoid,$userid) && !scorm_seq_is('active',$scoid,$userid)){
			$r = get_record('scorm_scoes_track','scoid',$scoid,'userid',$userid,'element','randomizationtiming');

             switch($r->value) {

                
				case 'never':
                break;
             
                case 'oneachnewattempt':
                case 'once':
                    if(!scorm_seq_is('activityprogressstatus',$scoid,$userid)){
					    if(scorm_seq_is('randomizechildren',$scoid,$userid)){
					        $childlist = array();
							$res = scorm_get_available_children($sco);
							$i = sizeof($res)-1;
							$children = $res->value;

							while ($i>=0){
								$pos = array_rand($children);
								array_push($childlist,$children [$pos]);
								array_splice($children,$pos,1);
								$i--;
							}
							
							$clist = serialize ($childlist);
							scorm_seq_set('availablechildren', $scoid, $userid, false);
							scorm_seq_set('availablechildren', $scoid, $userid, $clist);


				        }
				    }
                break;