/**
 * Copyright (c) 2004 - 2011 Eike Stepper (Berlin, Germany) and others.
 * 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:
 *    Eike Stepper - initial API and implementation
 */
package org.eclipse.emf.cdo.threedee.ui;

import org.eclipse.emf.cdo.threedee.ui.ThreeDeeWorld.InfoPanel;
import org.eclipse.emf.cdo.threedee.ui.bundle.OM;
import org.eclipse.emf.cdo.threedee.ui.nodes.RootElementGroup;

import org.eclipse.swt.SWT;
import org.eclipse.swt.events.SelectionAdapter;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.Slider;
import org.eclipse.ui.IWorkbenchPage;
import org.eclipse.ui.PlatformUI;
import org.eclipse.ui.part.ViewPart;

import javax.media.j3d.DirectionalLight;
import javax.media.j3d.Transform3D;
import javax.media.j3d.TransformGroup;
import javax.vecmath.Vector3f;

import java.text.MessageFormat;

/**
 * @author Eike Stepper
 */
public class ParametersView extends ViewPart
{
  public static final String ID = "org.eclipse.emf.cdo.threedee.ui.ParametersView";

  public ParametersView()
  {
  }

  @Override
  public void createPartControl(Composite parent)
  {
    Composite composite = new Composite(parent, SWT.NONE);
    composite.setLayout(new GridLayout(3, false));

    try
    {
      IWorkbenchPage page = PlatformUI.getWorkbench().getActiveWorkbenchWindow().getActivePage();
      if (page == null)
      {
        return;
      }

      ThreeDeeView view = (ThreeDeeView)page.findView(ThreeDeeView.ID);
      createRootRadius(composite, view);
      createLightDirection(composite, view);
      createInfoPanelTransform(composite, view);
    }
    catch (Exception ex)
    {
      OM.LOG.error(ex);
    }
  }

  private void createRootRadius(Composite composite, ThreeDeeView view)
  {
    final ThreeDeeWorld world = view.getWorld();
    final RootElementGroup root = world.getRoot();

    final Transformer transformer = new Transformer(composite, "Radius", 0f, 2f, root.getRadiusFactor());
    transformer.addSelectionListener(new SelectionAdapter()
    {
      @Override
      public void widgetSelected(SelectionEvent e)
      {
        root.setRadiusFactor(transformer.getValue());
        world.layout();
      }
    });
  }

  private void createLightDirection(Composite composite, ThreeDeeView view)
  {
    final DirectionalLight directionalLight = view.getWorld().getDirectionalLight();

    Vector3f direction = new Vector3f();
    directionalLight.getDirection(direction);

    final Transformer xTransformer = new Transformer(composite, "Light X", -10f, 10f, direction.getX());
    final Transformer yTransformer = new Transformer(composite, "Light Y", -10f, 10f, direction.getY());
    final Transformer zTransformer = new Transformer(composite, "Light Z", -10f, 10f, direction.getZ());

    SelectionAdapter listener = new SelectionAdapter()
    {
      @Override
      public void widgetSelected(SelectionEvent e)
      {
        float x = (float)xTransformer.getValue();
        float y = (float)yTransformer.getValue();
        float z = (float)zTransformer.getValue();

        Vector3f direction = new Vector3f(x, y, z);
        directionalLight.setDirection(direction);
      }
    };

    xTransformer.addSelectionListener(listener);
    yTransformer.addSelectionListener(listener);
    zTransformer.addSelectionListener(listener);
  }

  private void createInfoPanelTransform(Composite composite, ThreeDeeView view)
  {
    InfoPanel infoPanel = view.getWorld().getInfoPanel();

    Transform3D transform = new Transform3D();

    final TransformGroup translationGroup = infoPanel.getTranslationGroup();
    translationGroup.getTransform(transform);
    Vector3f translation = new Vector3f();
    transform.get(translation);

    final TransformGroup scaleGroup = infoPanel.getScaleGroup();
    scaleGroup.getTransform(transform);
    double scale = transform.getScale();

    final Transformer xTransformer = new Transformer(composite, "Info X", -1f, 0f, translation.getX());
    final Transformer yTransformer = new Transformer(composite, "Info Y", 0f, 1f, translation.getY());
    final Transformer zTransformer = new Transformer(composite, "Info Z", -2f, 2f, translation.getZ());

    SelectionAdapter translationListener = new SelectionAdapter()
    {
      @Override
      public void widgetSelected(SelectionEvent e)
      {
        float x = (float)xTransformer.getValue();
        float y = (float)yTransformer.getValue();
        float z = (float)zTransformer.getValue();

        Transform3D transform = new Transform3D();
        transform.set(new Vector3f(x, y, z));
        translationGroup.setTransform(transform);
      }
    };

    xTransformer.addSelectionListener(translationListener);
    yTransformer.addSelectionListener(translationListener);
    zTransformer.addSelectionListener(translationListener);

    final Transformer scaleTransformer = new Transformer(composite, "Info Scale", 0.005f, 0.1f, scale);
    scaleTransformer.addSelectionListener(new SelectionAdapter()
    {
      @Override
      public void widgetSelected(SelectionEvent e)
      {
        Transform3D transform = new Transform3D();
        transform.setScale(scaleTransformer.getValue());
        scaleGroup.setTransform(transform);
      }
    });
  }

  @Override
  public void setFocus()
  {
  }

  /**
   * @author Eike Stepper
   */
  private static class Transformer
  {
    private static final int MAX = 1000;

    private double min;

    private double range;

    private Slider slider;

    public Transformer(final Composite parent, String text, float min, float max, double initial)
    {
      this.min = min;
      range = max - min;

      Label label = new Label(parent, SWT.NONE);
      label.setText(text + ":");
      label.setLayoutData(new GridData());

      slider = new Slider(parent, SWT.HORIZONTAL);
      slider.setLayoutData(new GridData(SWT.FILL, SWT.TOP, true, false));
      slider.setMinimum(0);
      slider.setMaximum(MAX);

      final Label value = new Label(parent, SWT.NONE);
      GridData data = new GridData(SWT.RIGHT, SWT.TOP, false, false);
      data.widthHint = 48;
      value.setLayoutData(data);

      addSelectionListener(new SelectionAdapter()
      {
        @Override
        public void widgetSelected(SelectionEvent e)
        {
          String format = MessageFormat.format("{0}", getValue());
          value.setText(format);
          // parent.layout();
        }
      });

      setValue(initial);
    }

    public void addSelectionListener(SelectionListener listener)
    {
      slider.addSelectionListener(listener);
    }

    public double getValue()
    {
      return slider.getSelection() * range / MAX + min;
    }

    public void setValue(double value)
    {
      slider.setSelection((int)((value - min) * MAX / range));
    }
  }
}