/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.    
 */

package org.apache.tuscany.sca.impl.layout;

import java.util.ArrayList;
import java.util.HashMap;
import org.apache.tuscany.sca.impl.artifacts.Component;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.NodeList;

public class EntityBuilder {

	private Document dom;
	private final int initPoint = 200;//initial point
	private final int spaceX = Component.DEFAULT_WIDTH*2;
	private final int spaceY = Component.DEFAULT_HEIGHT*2;
	private ArrayList<Integer> levelCount = new ArrayList<Integer>();//keeps track of levels used in lanes
	//components connected to each other are tracked using following map
	private HashMap<String, ArrayList<String>> connectedEntities = new HashMap<String, ArrayList<String>>();
	private int totalWidth=0;
	private int totalHeight=0;
	private ComponentEntity startEnt = null;
	//private String compositeName;
	
	CompositeEntity composite = null;
	
	/**
	 * Constructor which initiates the DOM document
	 * @param aDom DOM document
	 */
	public EntityBuilder(Document aDom){
		dom = aDom;
	}

	public CompositeEntity buildCompositeEntity(){
		
		//get the root element
		Element docEle = dom.getDocumentElement();
		
		String compositeName;
		compositeName = docEle.getAttribute("name");
		//System.out.println("compositeName "+compositeName);
		
		ComponentEntity[] comps = buildComponentEntities(docEle);
		
		composite = new CompositeEntity(compositeName);
		
		setParent(comps, composite);
		
		//System.out.println("ComponentEntity "+comps[0].getLevel());
		int[][] conns = buildConnectionMatrix(comps);
		
		composite.setComponentList(comps);
		composite.setConnections(conns);
		
		LayoutBuilder buildLayout = new LayoutBuilder(comps , conns);
		buildLayout.buildEntities();
		
		
		System.out.println("conns "+conns[0][0]);
		
		
		buildCompositeService(docEle, composite);
		buildCompositeReference(docEle, composite);
		buildCompositeProperty(docEle, composite);
		
		composite.setAttributes();
		
		return composite;
	}
	
//	private void assignCoordinates() {
//
//		for(Entity ent: elts){
//			ent.setX(ent.getParent().getX() + ent.getStartPosition());
//			ent.setY(ent.getParent().getY() + ent.getStartPosition()/2);
//		}
//	}
	
	private void setParent(ComponentEntity[] comps, Entity parent) {

		for(ComponentEntity comp: comps){
			comp.setParent(parent);
		}
	}

	private void buildCompositeService(Element docEle,
			CompositeEntity composite) {

		NodeList nl = docEle.getElementsByTagName("service");
		System.err.println("^^^^^^^^^ "+nl.getLength());
		if(nl != null && nl.getLength() > 0 ) {
			
			for(int i = 0 ; i < nl.getLength();i++) {
				
				Element elt = (Element)nl.item(i);
				
				if(elt.getParentNode().getNodeName().equals("composite")){
					String compositeSer = elt.getAttribute("name");
					composite.addAService(compositeSer);

					String target = elt.getAttribute("promote");

					String service, serviceComp;
					String[] arr1 = extractComp(target);
					serviceComp = arr1[0];
					service = arr1[1];

					if(service == null){
						composite.addToPromoteAService(compositeSer, serviceComp);
					}
					else{
						composite.addToPromoteAService(compositeSer, service);
					}
				}

			}
		}
	}
	
	private void buildCompositeReference(Element docEle,
			CompositeEntity composite) {

		NodeList nl = docEle.getElementsByTagName("reference");
		//System.out.println("^^^^^^^^^ "+nl.getLength());
		if(nl != null && nl.getLength() > 0 ) {
			
			for(int i = 0 ; i < nl.getLength();i++) {
				
				Element elt = (Element)nl.item(i);
				
				if(elt.getParentNode().getNodeName().equals("composite")){
					String compositeRef = elt.getAttribute("name");
					composite.addAReference(compositeRef);

					String target = elt.getAttribute("promote");

					String reference, referenceComp;
					String[] arr1 = extractComp(target);
					referenceComp = arr1[0];
					reference = arr1[1];

					if(reference == null){
						composite.addToPromoteAReference(compositeRef, referenceComp);
					}
					else{
						composite.addToPromoteAReference(compositeRef, reference);
					}

				}
			}
		}
	}
	
	private void buildCompositeProperty(Element docEle,
			CompositeEntity composite) {

		NodeList nl = docEle.getElementsByTagName("property");
		//System.out.println("^^^^^^^^^ "+nl.getLength());
		if(nl != null && nl.getLength() > 0 ) {
			
			for(int i = 0 ; i < nl.getLength();i++) {
				
				Element elt = (Element)nl.item(i);
				
				if(elt.getParentNode().getNodeName().equals("composite")){
					String compositeProp = elt.getAttribute("name");
					composite.addAProperty(compositeProp);
				}
			}
		}
	}

	private int[][] buildConnectionMatrix(ComponentEntity[] comps) {

		int[][] connections = new int[comps.length][comps.length];
		connections = initConnections(connections);
		
//		//sec. 5.4 in the spec
//		NodeList nl = docEle.getElementsByTagName("wire");
//		//System.out.println("^^^^^^^^^ "+nl.getLength());
//		if(nl != null && nl.getLength() > 0 ) {
//			
//			for(int i = 0 ; i < nl.getLength();i++) {
//				
//				Element elt = (Element)nl.item(i);
//				
//				String source = elt.getAttribute("source");
//				String target = elt.getAttribute("target");
//				
//				String service, serviceComp, reference, referenceComp;
//				
//				String[] arr1 = extractComp(target);
//				serviceComp = arr1[0];
//				service = arr1[1];
//				
//				String[] arr2 = extractComp(source);
//				referenceComp = arr2[0];
//				reference = arr2[1];
				
//				//System.out.println("^^^^^^^^^ "+source+" ::: "+target);
//				if(target.contains("/")){
//					String[] arr = target.split("/");
//					serviceComp = arr[0];
//					service = arr[1];
//				}
//				else{
//					serviceComp = target;
//					service = null;
//				}
//				
//				if(source.contains("/")){
//					String[] arr = source.split("/");
//					referenceComp = arr[0];
//					reference = arr[1];
//				}
//				else{
//					referenceComp = source;
//					reference = null;
//				}
//				//sec. 5.4 in the spec
//		NodeList nl = docEle.getElementsByTagName("wire");
//		//System.out.println("^^^^^^^^^ "+nl.getLength());
//		if(nl != null && nl.getLength() > 0 ) {
//			
//			for(int i = 0 ; i < nl.getLength();i++) {
//				
//				Element elt = (Element)nl.item(i);
//				
//				String source = elt.getAttribute("source");
//				String target = elt.getAttribute("target");
//				
//				String service, serviceComp, reference, referenceComp;
//				
//				String[] arr1 = extractComp(target);
//				serviceComp = arr1[0];
//				service = arr1[1];
//				
//				String[] arr2 = extractComp(source);
//				referenceComp = arr2[0];
//				reference = arr2[1];
		 
		for(Entity ent: comps){
			for(String name: ent.getAdjacentEntities()){
				ComponentEntity e2 = findEntity(comps, name);
				if(ent != null && e2 != null){
					System.out.println("^^^^^^^^^ "+e2.getName());
					connections[ent.getId()][e2.getId()] = 1;
				}
			}
				
		}
//				ComponentEntity e1 = findEntity(comps, referenceComp);
//				ComponentEntity e2 = findEntity(comps, serviceComp);
//				
//				System.out.println("^^^^^^^^^ "+e1.getName());
//				if(e1 != null && e2 != null){
//					System.out.println("^^^^^^^^^ "+e1.getId());
//					connections[e1.getId()][e2.getId()] = 1;
//					createConnection(e1, reference, serviceComp, service);
//				}
//			}
//		}
//		
		return connections;
	}

	private String[] extractComp(String str) {
		
		String[] arr = new String[2];
		
		if(str.contains("/")){
			arr = str.split("/");
		}
		else{
			arr[0] = str;
			arr[1] = null;
		}
		return arr;
	}

	private int[][] initConnections(int[][] connections) {

		for(int i=0; i<connections.length ; i++){
			for(int j=0; j<connections.length ; j++){
				connections[i][j] =0;
			}
		}
		return connections;
	}

	/**
	 * Layout Building Algorithm
	 * ~~~~~~~~~~~~~~~~~~~~~~~~~
	 * 
	 * An Entity object represents a component element of a composite XML.
	 * Here we position (i.e. assigning a level and a lane) all such components
	 * in a unique cell of a grid.
	 * 
	 * 		 	lane0	  lane1	  lane2	  lane3 ....
	 * 		 	 _______________________________
	 * level0	|		|		|		|		|
	 * 			|_______|_______|_______|_______|
	 * level1	|		|		|		|		|
	 * 			|_______|_______|_______|_______|
	 * level2	|		|		|		|		|     
	 * 
	 * 1) Determining the Entity at level0, lane0 (starting entity)
	 * 		-First Entity in the list of Entities which has one or more adjacent Entities
	 * 		-If there is only one Entity it will eventually chosen
	 * 
	 * 2) Get adjacent Entities of starting Entity. 
	 * 		* If there are adjacent entities;
	 * 			*For each adjacent Entity; 
	 * 	
	 * 
	 * @return
	 */
	public ComponentEntity[] buildComponentEntities(Element docEle){
		
		ComponentEntity[] elts = null;
		
//		//get the root element
//		Element docEle = dom.getDocumentElement();
//		compositeName = docEle.getAttribute("name");
//		System.out.println("compositeName "+compositeName);

		//get a nodelist of elements
		NodeList nl = docEle.getElementsByTagName("component");
		if(nl != null && nl.getLength() > 0 ) {
			elts = new ComponentEntity[nl.getLength()];
			
			for(int i = 0 ; i < nl.getLength();i++) {
				elts[i] = new ComponentEntity();
				Element nVal = (Element)nl.item(i);
				//System.out.println(nVal.hasAttribute("name"));
				elts[i].setId(i);
				elts[i].setName(nVal.getAttribute("name"));
				
				setServices(nVal, elts[i]);
				setReferences(nVal, elts[i]);
				setProperties(nVal, elts[i]);
				
				elts[i].referenceHeight();
				elts[i].serviceHeight();
				elts[i].propertyLength();
			}
		}
		
		buildWires(docEle, elts);
//		//sec. 5.4 in the spec
//		nl = docEle.getElementsByTagName("wire");
//		System.out.println("^^^^^^^^^ "+nl.getLength());
//		if(nl != null && nl.getLength() > 0 ) {
//			for(int i = 0 ; i < nl.getLength();i++) {
//				Element elt = (Element)nl.item(i);
//				String source = elt.getAttribute("source");
//				String target = elt.getAttribute("target");
//				String service, serviceComp, reference, referenceComp;
//				
//				System.out.println("^^^^^^^^^ "+source+" ::: "+target);
//				if(target.contains("/")){
//					String[] arr = target.split("/");
//					serviceComp = arr[0];
//					service = arr[1];
//				}
//				else{
//					serviceComp = target;
//					service = null;
//				}
//				
//				if(source.contains("/")){
//					String[] arr = source.split("/");
//					referenceComp = arr[0];
//					reference = arr[1];
//				}
//				else{
//					referenceComp = source;
//					reference = null;
//				}
//				
//				ComponentEntity e = findEntity(referenceComp);
//				System.out.println("^^^^^^^^^ "+e.getName());
//				if(e != null){
//					createConnection(e, reference, serviceComp, service);
//				}
//			}
//		}
//
//		positionEntities(elts);
//
//		calculateProperties(elts);
	//	print(elts);

		return elts;

	}
	
	private void buildWires(Element docEle, ComponentEntity[] elts) {

		//sec. 5.4 in the spec
		NodeList nl = docEle.getElementsByTagName("wire");
		//System.out.println("^^^^^^^^^ "+nl.getLength());
		if(nl != null && nl.getLength() > 0 ) {
			
			for(int i = 0 ; i < nl.getLength();i++) {
				
				Element elt = (Element)nl.item(i);
				
				String source = elt.getAttribute("source");
				String target = elt.getAttribute("target");
				
				String service, serviceComp, reference, referenceComp;
				
				String[] arr1 = extractComp(target);
				serviceComp = arr1[0];
				service = arr1[1];
				
				String[] arr2 = extractComp(source);
				referenceComp = arr2[0];
				reference = arr2[1];
				
//				//System.out.println("^^^^^^^^^ "+source+" ::: "+target);
//				if(target.contains("/")){
//					String[] arr = target.split("/");
//					serviceComp = arr[0];
//					service = arr[1];
//				}
//				else{
//					serviceComp = target;
//					service = null;
//				}
//				
//				if(source.contains("/")){
//					String[] arr = source.split("/");
//					referenceComp = arr[0];
//					reference = arr[1];
//				}
//				else{
//					referenceComp = source;
//					reference = null;
//				}
//				
				ComponentEntity e1 = findEntity(elts, referenceComp);
				//ComponentEntity e2 = findEntity(comps, serviceComp);
				
				System.out.println("^^^^^^^^^ "+e1.getName());
				if(e1 != null){
					System.out.println("^^^^^^^^^ "+e1.getId());
					//connections[e1.getId()][e2.getId()] = 1;
					createConnection(e1, reference, serviceComp, service);
				}
			}
		}

	}

	private ComponentEntity findEntity(ComponentEntity[] elts, String componentName) {

		for(ComponentEntity e: elts){
			if(e.getName().equals(componentName)){
				return e;
			}
		}
		return null;
	}

	private void setReferences(Element nVal, ComponentEntity ent) {

		NodeList nl = nVal.getElementsByTagName("reference");
		if(nl != null && nl.getLength() > 0 ) {
			for(int i = 0 ; i < nl.getLength();i++) {
				Element elt = (Element)nl.item(i);
				String target = elt.getAttribute("target");
				String ref = elt.getAttribute("name");
				if(target.contains("/")){
					String[] arr = target.split("/");
					createConnection(ent, ref, arr[0], arr[1]);
//					ent.addToRefToSerMap(ref, arr[1]);
//					ent.addAnAdjacentEntity(arr[0]);
//					addToConnectedEntities(ent.getComponentName(), arr[0]);
//					addToConnectedEntities(arr[0], ent.getComponentName());
				}
				else if(!target.equals("")){
					createConnection(ent, ref, target, null);
//					ent.addToRefToSerMap(ref, target);
//					ent.addAnAdjacentEntity(target);
//					addToConnectedEntities(ent.getComponentName(), target);
//					addToConnectedEntities(target, ent.getComponentName());
				}

				ent.addAReference(ref);

			}
		}
	}

	private void createConnection(ComponentEntity ent, String reference,
			String serviceComp, String service) {

		String referenceComp = ent.getName();

		if(reference != null &&  service != null){

			ent.addToRefToSerMap(reference, service);
			ent.addAnAdjacentEntity(serviceComp);
			addToConnectedEntities(referenceComp, serviceComp);
			addToConnectedEntities(serviceComp, referenceComp);
		}
		else if(reference == null &&  service != null){
			ent.addToRefToSerMap(referenceComp, service);
			ent.addAnAdjacentEntity(serviceComp);
			addToConnectedEntities(referenceComp, serviceComp);
			addToConnectedEntities(serviceComp, referenceComp);
		}
		else if(reference != null &&  service == null){
			ent.addToRefToSerMap(reference, serviceComp);
			ent.addAnAdjacentEntity(serviceComp);
			addToConnectedEntities(referenceComp, serviceComp);
			addToConnectedEntities(serviceComp, referenceComp);
		}
		else{
			ent.addToRefToSerMap(referenceComp, serviceComp);
			ent.addAnAdjacentEntity(serviceComp);
			addToConnectedEntities(referenceComp, serviceComp);
			addToConnectedEntities(serviceComp, referenceComp);
		}
	}

//	private void calculateProperties(ComponentEntity[] elts) {
//		int level=0, lane=0;
//
//		for(ComponentEntity ent: elts){
//			level = max(level, ent.getLevel());
//			lane = max(lane, ent.getLane());
//
//		}
//		totalHeight += spaceY*(level+1) + initPoint;
//		totalWidth += spaceX*(lane+1) + initPoint;
//		
//		System.err.println(totalHeight + " :: "+totalWidth);
//	}
	
//	private int max(int a, int b){
//		if(a>=b)
//			return a;
//		return b;
//	}

	
	private void print(ComponentEntity[] elts) {

		for(ComponentEntity ent: elts){
			System.out.println(ent.getName()+" : "+ent.getLevel()+" : "
					+ent.getLane()+" : "+ent.getX()+" : "+ent.getY());
		}
	}

//	private void positionEntities(ComponentEntity[] ents){
//		
//		for(ComponentEntity ent: ents){
//			if(ent.getAdjacentEntities().size() != 0 || ents.length==1){
//				setPosition(ent, initPoint, initPoint, 0, 0);
//				levelCount.add(0, 1);
//				startEnt = ent;
//				System.err.println(ent.getName());
//				break;
//			}
//		}
//		
//
//		if(startEnt != null)
//			assignPositions(ents, startEnt);
//
//	}
//
//	private void assignPositions(ComponentEntity[] ents, ComponentEntity ent){
//		int i=0;
//		if(ent.getAdjacentEntities().size()>0){
//			
//			System.out.println(ent.getName());
//			for(String name: ent.getAdjacentEntities()){
//				//System.out.println("eee "+name);
//				for(ComponentEntity aEnt: ents){
//					i++;
//					if(name.equalsIgnoreCase(aEnt.getName())){
//						int lane = ent.getLane()+1;
//						if(levelCount.size()<= lane){
//							levelCount.add(lane, 1);
//							setPosition(aEnt, ent.getX()+spaceX, ent.getY(), 0, lane);
//						}
//						else{
//							int level = levelCount.get(lane);
//							levelCount.add(lane, level+1);
//							setPosition(aEnt, ent.getX()+spaceX, ent.getY()+spaceY*level, level, lane);
//						}
//						if(i<ents.length)
//							assignPositions(ents, aEnt);
////						else
////							System.out.println(i+ " <<<<< "+ents.length);
//						break;
//					}
//
//				}
//			}
//		}
//
//
//		else{
//			ArrayList<String> conns = connectedEntities.get(ent.getName());
//			System.err.println(conns.size());
//			if(conns.size()>0){
//
//				for(String conn: conns){
//					System.err.println("conn "+conn +" : "+ent.getName());
//					for(ComponentEntity e: ents){
//						if(e.getLane() == -1 && e.getName().equals(conn)){
//
//							int lane = ent.getLane()-1;
//							System.err.println(lane);
//							int level = levelCount.get(lane);
//							levelCount.add(lane, level+1);
//							setPosition(e, ent.getX()-spaceX, ent.getY()+spaceY*level, level, lane);
//
//							break;
//						}
//					}
//				}
//			}
//		}
//	}
//
//	private void setPosition(ComponentEntity ent, int x, int y, int level, int lane){
//		ent.setX(x);
//		ent.setY(y);
//		ent.setLevel(level);
//		ent.setLane(lane);
//	}
//
//
//	private String[] splitValues(String str){
//		return str.split("/");
//	}

	

	private void addToConnectedEntities(String ent1, String ent2) {
		System.err.println(ent1+" : "+ent2);
		ArrayList<String> list;
		if(connectedEntities.containsKey(ent1)){
			list = connectedEntities.get(ent1);
			
		}
		else{
			list =new ArrayList<String>();
			
		}
		list.add(ent2);
		connectedEntities.put(ent1, list);
	}

	private void setServices(Element nVal, ComponentEntity ent) {

		NodeList nl = nVal.getElementsByTagName("service");
		if(nl != null && nl.getLength() > 0 ) {
			for(int i = 0 ; i < nl.getLength();i++) {
				Element elt = (Element)nl.item(i);
				ent.addAService(elt.getAttribute("name"));
			}
		}
		else{
		
		NodeList nl1 = nVal.getElementsByTagName("implementation.java");
		if(nl1 != null && nl1.getLength() > 0 ) {
			for(int i = 0 ; i < nl1.getLength();i++) {
				Element elt = (Element)nl1.item(i);
				System.out.println(elt.getAttribute("class"));
				String serName = extractServiceName(elt.getAttribute("class"));
				ent.addAService(serName);
			}
		}
		
		}
		
	}

	/**
	 * 
	 * This will extract the service name part from the class attribute of 
	 * implementation.java element. 
	 * eg: if class = "NirmalServiceImpl", returning service name would be "NirmalService"
	 */
	private String extractServiceName(String classAttr) {
		if(classAttr != null){
			String[] x=classAttr.split("\\.");
			String name = x[x.length-1];
			if(name.endsWith("Impl")){
				return name.substring(0, name.length()-4);
			}
			else{
				return name;
			}
		}
		return "";
	}

	private void setProperties(Element nVal, ComponentEntity ent) {

		NodeList nl = nVal.getElementsByTagName("property");
		if(nl != null && nl.getLength() > 0 ) {
			for(int i = 0 ; i < nl.getLength();i++) {
				Element elt = (Element)nl.item(i);
				ent.addAProperty(elt.getAttribute("name"));
			}
		}
	}

//	public void setCompositeName(String compositeName) {
//		this.compositeName = compositeName;
//	}
//
//	public String getCompositeName() {
//		return compositeName;
//	}

	public int getTotalWidth() {
		return totalWidth;
	}

	public int getTotalHeight() {
		return totalHeight;
	}



}