package com.camunda.consulting.bpmndi_example;

import java.io.File;
import java.io.IOException;
import org.camunda.bpm.model.bpmn.Bpmn;
import org.camunda.bpm.model.bpmn.BpmnModelInstance;
import org.camunda.bpm.model.bpmn.instance.BaseElement;
import org.camunda.bpm.model.bpmn.instance.BpmnModelElementInstance;
import org.camunda.bpm.model.bpmn.instance.Definitions;
import org.camunda.bpm.model.bpmn.instance.EndEvent;
import org.camunda.bpm.model.bpmn.instance.FlowNode;
import org.camunda.bpm.model.bpmn.instance.Process;
import org.camunda.bpm.model.bpmn.instance.SequenceFlow;
import org.camunda.bpm.model.bpmn.instance.StartEvent;
import org.camunda.bpm.model.bpmn.instance.UserTask;
import org.camunda.bpm.model.bpmn.instance.bpmndi.BpmnDiagram;
import org.camunda.bpm.model.bpmn.instance.bpmndi.BpmnEdge;
import org.camunda.bpm.model.bpmn.instance.bpmndi.BpmnLabel;
import org.camunda.bpm.model.bpmn.instance.bpmndi.BpmnPlane;
import org.camunda.bpm.model.bpmn.instance.bpmndi.BpmnShape;
import org.camunda.bpm.model.bpmn.instance.dc.Bounds;
import org.camunda.bpm.model.bpmn.instance.di.Waypoint;

public class ProcessGenerator {

  public BpmnModelInstance modelInstance;

  public static void main(String[] args) throws IOException {
    ProcessGenerator createProcess = new ProcessGenerator();
    createProcess.generateProcess();
  }

  public void generateProcess() throws IOException {
    modelInstance = Bpmn.createEmptyModel();
    Definitions definitions = modelInstance.newInstance(Definitions.class);
    definitions.setTargetNamespace("http://camunda.org/examples");
    modelInstance.setDefinitions(definitions);

    // create the process
    org.camunda.bpm.model.bpmn.instance.Process process = modelInstance.newInstance(Process.class);
    process.setAttributeValue("id", "process-one-task", true);
    definitions.addChildElement(process);

    BpmnDiagram diagram = modelInstance.newInstance(BpmnDiagram.class);
    BpmnPlane plane = modelInstance.newInstance(BpmnPlane.class);
    plane.setBpmnElement(process);
    diagram.setBpmnPlane(plane);
    definitions.addChildElement(diagram);
    
    // create start event, user task and end event
    StartEvent startEvent = createElement(process, "start", "Di generation wanted", 
        StartEvent.class, plane, 15, 15, 50, 50, true);
    
    UserTask userTask = createElement(process, "userTask", "Generate Model with DI", 
        UserTask.class, plane, 100, 0, 80, 100, false);
    
    createSequenceFlow(process, startEvent, userTask, plane, 65, 40, 100, 40);
    
    EndEvent endEvent = createElement(process, "end", "DI generation completed", 
        EndEvent.class, plane, 250, 15, 50, 50, true);
    
    createSequenceFlow(process, userTask, endEvent, plane, 200, 40, 250, 40);
    
    // validate and write model to file
    Bpmn.validateModel(modelInstance);
    File file = File.createTempFile("bpmn-model-api-", ".bpmn");
    Bpmn.writeModelToFile(file, modelInstance);  
    
  }

  protected <T extends BpmnModelElementInstance> T createElement(BpmnModelElementInstance parentElement, 
      String id, String name, Class<T> elementClass, BpmnPlane plane, 
      double x, double y, double heigth, double width, boolean withLabel) {
    T element = modelInstance.newInstance(elementClass);
    element.setAttributeValue("id", id, true);
    element.setAttributeValue("name", name, false);
    parentElement.addChildElement(element);
    
    BpmnShape bpmnShape = modelInstance.newInstance(BpmnShape.class);
    bpmnShape.setBpmnElement((BaseElement) element);
    
    Bounds bounds = modelInstance.newInstance(Bounds.class);
    bounds.setX(x);
    bounds.setY(y);
    bounds.setHeight(heigth);
    bounds.setWidth(width);
    bpmnShape.setBounds(bounds);
    
    if (withLabel) {
      BpmnLabel bpmnLabel = modelInstance.newInstance(BpmnLabel.class);
      Bounds labelBounds = modelInstance.newInstance(Bounds.class);
      labelBounds.setX(x);
      labelBounds.setY(y + heigth);
      labelBounds.setHeight(heigth);
      labelBounds.setWidth(width);
      bpmnLabel.addChildElement(labelBounds);
      bpmnShape.addChildElement(bpmnLabel);
    }
    plane.addChildElement(bpmnShape);
    
    return element;
  }
  
  public SequenceFlow createSequenceFlow(org.camunda.bpm.model.bpmn.instance.Process process, FlowNode from, FlowNode to, BpmnPlane plane,
      int... waypoints) {
    String identifier = from.getId() + "-" + to.getId();
    SequenceFlow sequenceFlow = modelInstance.newInstance(SequenceFlow.class);
    sequenceFlow.setAttributeValue("id", identifier, true);
    process.addChildElement(sequenceFlow);
    sequenceFlow.setSource(from);
    from.getOutgoing().add(sequenceFlow);
    sequenceFlow.setTarget(to);
    to.getIncoming().add(sequenceFlow);
    
    BpmnEdge bpmnEdge = modelInstance.newInstance(BpmnEdge.class);
    bpmnEdge.setBpmnElement(sequenceFlow);
    for (int i = 0; i < waypoints.length / 2; i++) {
      double waypointX = waypoints[i*2];
      double waypointY = waypoints[i*2+1];
      Waypoint wp = modelInstance.newInstance(Waypoint.class);
      wp.setX(waypointX);
      wp.setY(waypointY);
      bpmnEdge.addChildElement(wp);
    }
    plane.addChildElement(bpmnEdge);
    
    return sequenceFlow;
  }
  
}