package org.simantics.modeling.template2d.ui.function;

import java.util.Vector;

import org.simantics.databoard.Bindings;
import org.simantics.db.ReadGraph;
import org.simantics.db.Resource;
import org.simantics.db.WriteGraph;
import org.simantics.db.common.request.ReadRequest;
import org.simantics.db.common.request.WriteRequest;
import org.simantics.db.exception.DatabaseException;
import org.simantics.db.layer0.variable.Variable;
import org.simantics.db.layer0.variable.Variables;
import org.simantics.diagram.function.PredefinedVariables;
import org.simantics.diagram.stubs.DiagramResource;
import org.simantics.image2.ontology.ImageResource;
import org.simantics.modeling.template2d.ontology.Template2dResource;
import org.simantics.project.ontology.ProjectResource;
import org.simantics.simulation.ontology.SimulationResource;
import org.simantics.utils.ui.dialogs.ShowMessage;

public class LinkSVGImage {
	
    public static void linkSVGImage(WriteGraph graph, final Resource parent, final Resource child) {
    	
    	final String[] uri = {null};
    	final String[] msg = {null};
    	final String errmsg = "Creation of image reference failed. Activate an experiment and try to copy and paste an image again.";
    	
    	try {
			graph.syncRequest(new ReadRequest() {
				@Override
				public void run(ReadGraph g) throws DatabaseException {
					if (parent == null || child == null) {
						msg[0] = errmsg; 
						return;
					}
					//Layer0 L0 = Layer0.getInstance(g);
					ImageResource IMG = ImageResource.getInstance(g);
					if (!g.isInstanceOf(child, IMG.SvgImage)){
						msg[0] = errmsg; 
						return;
					}
					
					Variable parentV = Variables.getVariable(g, parent);
					if (parentV == null){
						msg[0] = errmsg; 
						return;
					}
					
					Vector<Variable> grandOfParent = new Vector<Variable>();
					Variable tmp = parentV;
					do {
						grandOfParent.add(0, tmp);
						tmp = tmp.getParent(g);
					}
					while (tmp != null);
					
//					System.err.println(parentV.getURI(g));
//					String parentUri = parentV.getURI(g);
					
					Variable childV = Variables.getVariable(g, child);
					String childUri = null;
					if (childV == null){
						msg[0] = errmsg; 
						return;
					}
					
					Vector<Variable> grandOfChild = new Vector<Variable>();
					tmp = childV;
					do {
						grandOfChild.add(0, tmp);
						tmp = tmp.getParent(g);
					}
					while (tmp != null);
					
					int k = -1; // index of the most nearest common parent
					int maxLen = (grandOfChild.size() < grandOfParent.size())? grandOfChild.size() : grandOfParent.size(); 
					for (int i = 0;i < maxLen; i++){
						if (grandOfChild.get(i).equals(grandOfParent.get(i)))
							k++;
						else
							break;
					}
					if (k == -1) // no common parent
					{
						msg[0] = errmsg; 
						return;
					}
					//StructuralResource2 STR = StructuralResource2.getInstance(g);
					SimulationResource SIMU = SimulationResource.getInstance(g);
					ProjectResource PROJ = ProjectResource.getInstance(g);
                    Template2dResource TEPLATE2D = Template2dResource.getInstance(g);
					Resource root = g.getRootLibrary();;
					Resource type = null;
					String predefined = null;
					Resource res = null;
					for (;k >= 0;k--){
						tmp = grandOfChild.get(k);
						res = tmp.getRepresents(g);
						if (res.equals(root)){
							predefined = PredefinedVariables.root;
							break;
						}
						type = g.getPossibleType(res, SIMU.Model);
						if (type != null){
							predefined = PredefinedVariables.model;
							break;
						}
						type = g.getPossibleType(res, PROJ.Project);
						if (type != null){
							predefined = PredefinedVariables.project;
							break;
						}
						type = g.getPossibleType(res, TEPLATE2D.DrawingTemplate);
						if (type != null){
							predefined = PredefinedVariables.template;
							break;
						}
					}
					if (predefined == null) // no predefined common parent
					{
						msg[0] = errmsg; 
						return;
					}
					Variable resV = Variables.getVariable(g, res);
					String resUri = resV.getURI(g);
					
					childUri = childV.getURI(g);
//					System.err.println(childUri);

					Resource childModel = Variables.getModel(g, childV);
					Resource parentModel = Variables.getModel(g, parentV);
					if (childModel == null || parentModel == null){
						msg[0] = errmsg; 
						return;
					}
					
					if (!parentModel.equals(childModel)){
						msg[0] = errmsg;
						return;
					}

//					Variable modelV = Variables.getVariable(g, childModel);
//					if (modelV == null){
//						msg[0] = errmsg[0];
//						return;
//					}
//					
//					String modelUri = modelV.getURI(g);

					if (childUri.startsWith(resUri)){
						uri[0] = childUri.substring(resUri.length());
						uri[0] = "pre:/" + predefined + uri[0];
//						System.err.println(uri);
					}
				}
			});
			graph.syncRequest(new WriteRequest() {
				@Override
				public void perform(WriteGraph g) throws DatabaseException {
					if (uri == null || parent == null){
						msg[0] = errmsg;
						return;
					}
					DiagramResource DIA = DiagramResource.getInstance(g);
                    Template2dResource TEMPLATE2D = Template2dResource.getInstance(g);

					Resource var = g.getPossibleObject(parent, DIA.Scenegraph_SVGImage_document);
					if (var == null){
						msg[0] = "Creation of image reference failed. Only SVG images are supported for now.";
						return;
					}
					
					g.claimLiteral(var, TEMPLATE2D.Profiles_VariableReference_path, uri[0] + "#data", Bindings.STRING);
				}
			});
			if (msg[0] != null){
				ShowMessage.showWarning("Warning", msg[0]);
			}
		} catch (Exception e) {
			// TODO: handle exception
			e.printStackTrace();
		}
	
	}
	

}