package org.simantics.views.swt.loader;

import org.eclipse.swt.SWT;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.TreeItem;
import org.simantics.browsing.ui.BuiltinKeys;
import org.simantics.browsing.ui.NodeContext;
import org.simantics.databoard.Bindings;
import org.simantics.db.ReadGraph;
import org.simantics.db.Resource;
import org.simantics.db.VirtualGraph;
import org.simantics.db.WriteGraph;
import org.simantics.db.common.request.ResourceRead;
import org.simantics.db.common.request.WriteRequest;
import org.simantics.db.exception.DatabaseException;
import org.simantics.db.layer0.util.Simantics;
import org.simantics.db.layer0.variable.Variable;
import org.simantics.scenegraph.ParentNode;
import org.simantics.scenegraph.loader.ScenegraphLoader;
import org.simantics.views.ViewUtils;
import org.simantics.views.ontology.ViewsResources;
import org.simantics.views.swt.client.base.ISWTViewNode;
import org.simantics.views.swt.client.impl.SWTExplorer;

public class ExplorerLoader implements ScenegraphLoader {

	final private Resource configuration;
	
	public ExplorerLoader(Resource configuration) {
		this.configuration = configuration;
	}
	
	@Override
	public ISWTViewNode create(ParentNode<ISWTViewNode> parent, final Variable context) throws DatabaseException {
		
		SWTExplorer node = parent.addNode(SWTExplorer.class);
		
		node.setStyle(LoaderUtils.getStyle(configuration));

		String browseContextURI = Simantics.getSession().sync(new ResourceRead<String>(configuration) {

			@Override
			public String perform(ReadGraph graph) throws DatabaseException {
				ViewsResources VIEW = ViewsResources.getInstance(graph);
				Resource browseContext = graph.getSingleObject(resource, VIEW.Explorer_BrowseContext);
				return graph.getURI(browseContext);
			}
			
		});
		
		node.setBrowseContextURI(browseContextURI);
		
        node.setLayoutData(LoaderUtils.getGridData(configuration));
        
        node.setColumns(LoaderUtils.getColumns(configuration));
        
        LoaderUtils.listen(configuration, context, ViewsResources.URIs.Explorer_InputTransformation, node.getInputFunction());

        LoaderUtils.listen(configuration, context, ViewsResources.URIs.Explorer_HasColumnsVisible, node.getColumnsVisibleFunction());
        
		Listener selectionListener = Simantics.getSession().sync(new ResourceRead<Listener>(configuration) {

			@Override
			public Listener perform(ReadGraph graph) throws DatabaseException {
				ViewsResources VIEW = ViewsResources.getInstance(graph);
				Resource listener = graph.getPossibleObject(resource, VIEW.Explorer_SelectionListener);
				if(listener == null) return null;
				return graph.adapt(listener, Listener.class);
			}
			
		});
		
		if(selectionListener != null) node.addListenerToControl(SWT.Selection, selectionListener);
		
		node.addListenerToControl(SWT.Selection, new Listener() {
			
			@Override
			public void handleEvent(Event event) {
				
	            TreeItem item = (TreeItem)event.item;
//	            Tree tree = item.getParent();
//	            GraphExplorer explorer = (GraphExplorer)tree.getData("GraphExplorer");
//	            final Resource runtimeDiagram = (Resource)explorer.getRoot().getConstant(BuiltinKeys.INPUT);
//	            final boolean checked = item.getChecked();
	            NodeContext nc = (NodeContext)item.getData();
	            Object obj = nc.getConstant(BuiltinKeys.INPUT);

	            if (obj instanceof Variable) {
	                final Variable var = (Variable) obj;
	                Simantics.getSession().async(new WriteRequest(Simantics.getSession().getService(VirtualGraph.class)) {
	                    @Override
	                    public void perform(WriteGraph graph) throws DatabaseException {
	                        ViewsResources VIEW = ViewsResources.getInstance(graph);
	                        System.err.println("setParameter " + context.getURI(graph) + " -> " + var.getURI(graph));
	                        ViewUtils.setParameter(graph, context, VIEW.Explorer_Selection, var.getURI(graph), Bindings.STRING);
	                    }
	                });
	            }
			}
			
		});
		
		return node;
		
	}
	
}