package org.simantics.interop.update.model;

import java.util.ArrayList;
import java.util.Collection;
import java.util.HashSet;
import java.util.Set;

import org.simantics.db.Resource;
import org.simantics.db.exception.DatabaseException;
import org.simantics.interop.test.GraphChanges;

public class UpdateNode3 {
	
	UpdateNode un1;
	UpdateNode un2;
	UpdateNode un3;
	
	private Collection<UpdateNode3> children = new ArrayList<UpdateNode3>();
	
	
	public Collection<UpdateNode3> getChildren() {
		return children;
	}
	
	public UpdateNode getUn1() {
		return un1;
	}
	
	public UpdateNode getUn2() {
		return un2;
	}
	
	public UpdateNode getUn3() {
		return un3;
	}
	
	public UpdateNode3(UpdateNode un1, UpdateNode un2, UpdateNode un3) {
		this.un1 = un1;
		this.un2 = un2;
		this.un3 = un3;
	}
	
	public static UpdateNode3 getCombinedTree(ModelUpdate update) throws DatabaseException {
		UpdateTree updateTree1 = update.getUpdateTree();
		UpdateTree updateTree2 = update.getUpdateTree2();
		UpdateTree updateTree3 = update.getUpdateTree3();
		
		UpdateNode3 n3 = new UpdateNode3(updateTree1.getRootNode(), updateTree2.getRootNode(), updateTree3.getRootNode());
		
		populate(n3, update.getChanges(), update.getChanges2(), update.getChanges3());
		return n3;
	}
	
	private static void populate(UpdateNode3 un, GraphChanges gc1, GraphChanges gc2, GraphChanges gc3) {
		Set<UpdateNode> p1 = new HashSet<>();
		Set<UpdateNode> p2 = new HashSet<>();
		Set<UpdateNode> p3 = new HashSet<>();
		
		if (un.getUn1() != null) {
			for (UpdateNode n1 : un.getUn1().getChildren())  {
				p1.add(n1);
				UpdateNode n2 = null;
				if (un.getUn2() != null)
					n2 = getMathcing(n1, un.getUn2().getChildren(), gc1);
				UpdateNode n3 = null;
				if (un.getUn3() != null) {
					n3 = getMathcing(n1, un.getUn3().getChildren(), gc2);
					if (n3 == null && n2 != null)
						n3 = getMathcing(n2, un.getUn3().getChildren(), gc3);
				}
				UpdateNode3 cn = new UpdateNode3(n1, n2, n3);
				un.children.add(cn);
				populate(cn, gc1, gc2, gc3);
				
				if (n2 != null)
					p2.add(n2);
				if (n3 != null)
					p3.add(n3);
			}
		}
		if (un.getUn2() != null) {
			for (UpdateNode n2 : un.getUn2().getChildren())  {
				if (p2.contains(n2))
					continue;
				p2.add(n2);
				
				UpdateNode n3 = null;
				if (un.getUn3() != null) {
					n3 = getMathcing(n2, un.getUn3().getChildren(), gc3);
				}
				UpdateNode3 cn = new UpdateNode3(null, n2, n3);
				un.children.add(cn);
				populate(cn, gc1, gc2, gc3);
				
				if (n3 != null)
					p3.add(n3);
			}
		}
		if (un.getUn3() != null) {
			for (UpdateNode n3 : un.getUn3().getChildren())  {
				if (p3.contains(n3))
					continue;
				p3.add(n3);
				UpdateNode3 cn = new UpdateNode3(null, null, n3);
				un.children.add(cn);
				populate(cn, gc1, gc2, gc3);
			}
		}
	}
	
	private static UpdateNode getMathcing(UpdateNode n , Collection<UpdateNode> coll, GraphChanges gc) {
		if (n.getResource() == null) {
			if (coll.size() != 1)
				return null;
			UpdateNode n2 = coll.iterator().next();
			if (n2.getClass() != n.getClass())
				return null;
			return n2;
		}
		Resource o = gc.getComparable().getLeft(n.getResource());
		if (o == null)
			o = gc.getComparable().getRight(n.getResource());
		if (o == null)
			o = n.getResource();
		for (UpdateNode c : coll) {
			if (o.equals(c.getResource()))
				return c;
		}
		return null;
	}
}