class.ilBasicNode.php

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<?php
/* Copyright (c) 1998-2016 ILIAS open source, Extended GPL, see docs/LICENSE */

require_once './Services/WorkflowEngine/classes/nodes/class.ilBaseNode.php';

class ilBasicNode extends ilBaseNode
{
    private $is_forward_condition_node;

    public $is_forward_condition_event;

    public $ident;

    public function __construct(ilWorkflow $context)
    {
        $this->context = $context;
        $this->detectors = array();
        $this->emitters = array();
        $this->activities = array();
        $this->active = false;
        $this->is_forward_condition_node = false;
        $this->is_forward_condition_event = false;
        $this->ident = strtoupper(substr(md5(spl_object_hash($this)), 0, 6));
    }

    public function activate()
    {
        if ($this->isActive()) {
            return;
        }
        
        $this->active = true;

        foreach ($this->detectors as $detector) {
            $detector->onActivate();
        }
        $this->onActivate();
        $this->attemptTransition();
    }

    public function deactivate()
    {
        $this->active = false;
        foreach ($this->detectors as $detector) {
            $detector->onDeactivate();
        }
        $this->onDeactivate();
    }

    public function checkTransitionPreconditions()
    {
        // queries the $detectors if their conditions are met.
        $isPreconditionMet = true;
        foreach ($this->detectors as $detector) {
            if ($isPreconditionMet == true) {
                $isPreconditionMet = $detector->getDetectorState();
            }
        }
        return $isPreconditionMet;
    }

    public function attemptTransition()
    {
        if ($this->checkTransitionPreconditions() == true) {
            $this->executeTransition();
            return true;
        } else {
            return false;
        }
    }

    private function executeActivities()
    {
        if (count($this->activities) != 0) {
            foreach ($this->activities as $activity) {
                $activity->execute();
            }
        }
    }

    private function executeEmitters()
    {
        if (count($this->emitters) != 0) {
            foreach ($this->emitters as $emitter) {
                $emitter->emit();
            }
        }
    }

    public function executeTransition()
    {
        $this->deactivate();
        $this->executeActivities();
        $this->pingbackToPredecessorNodes();
        $this->executeEmitters();
    }

    public function notifyDetectorSatisfaction(ilDetector $detector)
    {
        if ($this->isActive()) {
            $this->attemptTransition();
        }
    }

    public function isForwardConditionNode()
    {
        return $this->is_forward_condition_node;
    }

    public function setIsForwardConditionNode($is_forward_condition_node)
    {
        $this->is_forward_condition_node = $is_forward_condition_node;
    }

    public function deactivateForwardConditionNodes(ilNode $activated_node)
    {
        if ($this->is_forward_condition_node) {
            foreach ($this->emitters as $emitter) {
                $target_detector = $emitter->getTargetDetector();

                $target_node = $target_detector->getContext();

                if ($target_node === $activated_node) {
                    continue;
                }
                $target_node->deactivate();
            }
        }
    }

    public function pingbackToPredecessorNodes()
    {
        foreach ($this->detectors as $detector) {
            $source_node = $detector->getSourceNode();
            if ($source_node && $source_node->is_forward_condition_node) {
                $source_node->deactivateForwardConditionNodes($this);
            }
        }
    }
}