/*******************************************************************************
 * Copyright (c) 2007, 2010 Association for Decentralized Information Management
 * in Industry THTH ry.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     VTT Technical Research Centre of Finland - initial API and implementation
 *******************************************************************************/
package org.simantics.graphviz.ui;

import java.awt.Canvas;
import java.awt.Frame;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.io.File;
import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.util.concurrent.atomic.AtomicBoolean;

import javax.swing.SwingUtilities;

import org.eclipse.swt.SWT;
import org.eclipse.swt.awt.SWT_AWT;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Shell;
import org.simantics.graphviz.Graph;
import org.simantics.graphviz.Graphs;
import org.simantics.graphviz.continuation.Computation;
import org.simantics.graphviz.continuation.Continuation;
import org.simantics.graphviz.drawable.GraphDrawable;
import org.simantics.graphviz.drawable.ViewerCanvas;
import org.simantics.utils.ui.SWTUtils;

public class GraphvizComponent extends Composite {

    Canvas canvas;
    GraphDrawable drawable;
    Graph graph;
    AtomicBoolean initialized = new AtomicBoolean(false);

    public GraphvizComponent(Composite parent, int style) {
        super(parent, style | SWT.EMBEDDED | SWT.NO_BACKGROUND);

        final Frame frame = SWT_AWT.new_Frame(this);
        workaroundJava7FocusProblem(frame);
        
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                try {
                    drawable = new GraphDrawable();
                    canvas = new ViewerCanvas(drawable);
                    frame.add(canvas);
                } finally {
                    synchronized (initialized) {
                        initialized.set(true);
                        initialized.notifyAll();
                    }
                }
            }

        });
    }
    
    private void workaroundJava7FocusProblem(Frame frame) {
        String ver = System.getProperty("java.version");
        if (ver.startsWith("1.7") || ver.startsWith("1.8")) {
            try {
                frame.addWindowListener(new Java7FocusFixListener(this, frame));
            } catch (SecurityException e) {
                e.printStackTrace();
                //Activator.getDefault().getLog().log(new Status(IStatus.ERROR, Activator.PLUGIN_ID, e.getMessage(), e));
            } catch (NoSuchMethodException e) {
                e.printStackTrace();
                //Activator.getDefault().getLog().log(new Status(IStatus.ERROR, Activator.PLUGIN_ID, e.getMessage(), e));
            }
        }
    }

    static class Java7FocusFixListener extends WindowAdapter {

        Method shellSetActiveControl;
        Control control;
        Frame frame;

        public Java7FocusFixListener(Control control, Frame frame) throws NoSuchMethodException, SecurityException {
            this.shellSetActiveControl = Shell.class.getDeclaredMethod("setActiveControl", Control.class);
            this.frame = frame;
            this.control = control;
        }

        @Override
        public void windowActivated(WindowEvent e) {
            SWTUtils.asyncExec(control, new Runnable() {
                @Override
                public void run() {
                    if (control.isDisposed())
                        return;
                    if (control.getDisplay().getFocusControl() == control) {
                        try {
                            boolean accessible = shellSetActiveControl.isAccessible();
                            if (!accessible)
                                shellSetActiveControl.setAccessible(true);
                            shellSetActiveControl.invoke(control.getShell(), control);
                            if (!accessible)
                                shellSetActiveControl.setAccessible(false);
                        } catch (SecurityException e) {
                            e.printStackTrace();
                            //Activator.getDefault().getLog().log(new Status(IStatus.ERROR, Activator.PLUGIN_ID, e.getMessage(), e));
                        } catch (IllegalArgumentException e) {
                            e.printStackTrace();
                            //Activator.getDefault().getLog().log(new Status(IStatus.ERROR, Activator.PLUGIN_ID, e.getMessage(), e));
                        } catch (IllegalAccessException e) {
                            e.printStackTrace();
                            //Activator.getDefault().getLog().log(new Status(IStatus.ERROR, Activator.PLUGIN_ID, e.getMessage(), e));
                        } catch (InvocationTargetException e) {
                            e.getCause().printStackTrace();
                            //Activator.getDefault().getLog().log(new Status(IStatus.ERROR, Activator.PLUGIN_ID, e.getMessage(), e));
                        }
                    }
                }
            });
        }

    }

    public void waitUntilInitialized() {
        try {
            synchronized (initialized) {
                while (!initialized.get())
                    initialized.wait();
            }
        } catch (InterruptedException e) {
            throw new Error("GraphvizComponent AWT population interrupted for class " + this, e);
        }
    }

    /**
     * Sets a new graph to be drawn. This operation may take a while. It can
     * be called from any thread. Automatically redraws the component.
     * @param graph
     */
    public void setGraph(Graph graph) {
        setGraph(graph, "dot");
    }

    /**
     * Sets a new graph to be drawn. This operation may take a while. It can
     * be called from any thread. Automatically redraws the component.
     * @param graph
     */
    public Computation<Graph> setGraph(Graph graph, String algorithm) {
        waitUntilInitialized();
        Computation<Graph> computation = drawable.setGraph(graph, algorithm);
        computation.addContinuation(new Continuation<Graph>() {

            @Override
            public void succeeded(Graph result) {
                if (isDisposed())
                    return;
                
                fit();
            }

            @Override
            public void failed(Exception exception) {
            }

        });
        return computation;
    }

    /**
     * Fits the content of the canvas to the component.
     * Can be called from any thread.
     */
    public void fit() {
        ((ViewerCanvas)canvas).fit();
        getDisplay().asyncExec(new Runnable() {

            @Override
            public void run() {
                if (!isDisposed())
                    redraw();
            }

        });
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                canvas.repaint();
            }

        });


    }

    public void requestFocus() {
        if(canvas != null)
            canvas.requestFocus();
    }
    
    public void save(File file) throws IOException {
    	if (drawable == null) {
			throw new IOException("Nothing to save");
		}
		Graph graph = drawable.getGraph();
		String algo = drawable.getAlgorithm();
	
		String type = getExtension(file);
		if (type == null)
			return;
		Graphs.createImage(graph, algo, type, file);
    }
    
    public String[] getFileExtensions() {
    	return new String[]{"*.svg","*.dot","*.eps", "*.jpg", "*.jpeg","*.pdf","*.png","*.ps"};
    }
    
    public String[] getFileNames() {
    	return new String[]{"Scalable Vector Graphics Image",  "DOT Image", "Encapsulated PostScript Image","JPG Image","JPG Image","Portable Document Format Image","Portable Network Graphics Image","PostScript Image"};
    }
    
    public static String getExtension(File file) {
		String filename = file.getName();
		int index = filename.lastIndexOf(".");
		if (index < 0)
			return null;
		return filename.substring(index+1).toLowerCase();
	}

}