EDIT

// $Id$

/**

* Copyright (C) 2007 EDIT

* European Distributed Institute of Taxonomy 

* http://www.e-taxonomy.eu

* 

* The contents of this file are subject to the Mozilla Public License Version 1.1

* See LICENSE.TXT at the top of this package for the full license terms.

*/

package eu.etaxonomy.taxeditor.view;

import org.eclipse.jface.dialogs.IDialogSettings;

import org.eclipse.jface.viewers.Viewer;

import org.eclipse.swt.SWT;

import org.eclipse.swt.custom.SashForm;

import org.eclipse.swt.events.ControlEvent;

import org.eclipse.swt.events.ControlListener;

import org.eclipse.swt.graphics.Point;

import org.eclipse.swt.widgets.Composite;

import org.eclipse.swt.widgets.Label;

import org.eclipse.ui.ISelectionListener;

import org.eclipse.ui.ISelectionService;

import org.eclipse.ui.part.PageBook;

import org.eclipse.ui.part.ViewPart;

import eu.etaxonomy.taxeditor.store.internal.TaxeditorStorePlugin;

/**

 * <p>Abstract AbstractSplitableViewPart class.</p>

 *

 * @author n.hoffmann

 * @created Feb 12, 2010

 * @version 1.0

 */

public abstract class AbstractSplitableViewPart extends ViewPart implements ISelectionListener{

	static final int VIEW_ORIENTATION_VERTICAL = 0;

	static final int VIEW_ORIENTATION_HORIZONTAL = 1;

	static final int VIEW_ORIENTATION_SINGLE = 2;

	static final int VIEW_ORIENTATION_AUTOMATIC = 3;

	private static final int PAGE_EMPTY = 0;

    private static final int PAGE_VIEWER = 1;

	private final IDialogSettings dialogSettings;

	private SashForm detailSplitter;

	private Composite parent;

	private PageBook pagebook;

	private int orientation;

	private int currentOrientation;

//

	private boolean showViewer2;

	private Viewer viewer1;

	private Viewer viewer2;

	private Label emptySelectionLabel;

	private ISelectionService selectionService;

	/**

	 * <p>Constructor for AbstractSplitableViewPart.</p>

	 */

	public AbstractSplitableViewPart() {

		super();

		dialogSettings = TaxeditorStorePlugin.getDefault().getDialogSettings();

	}

	/* (non-Javadoc)

	 * @see org.eclipse.ui.part.WorkbenchPart#createPartControl(org.eclipse.swt.widgets.Composite)

	 */

	/** {@inheritDoc} */

	@Override

	public void createPartControl(Composite parent) {	

		selectionService = getSite().getWorkbenchWindow().getSelectionService();

		selectionService.addSelectionListener(this);

		selectionService.addPostSelectionListener(this);

		this.parent = parent;

		addResizeListener(parent);

		pagebook = new PageBook(parent, SWT.NULL);

		// Page 1: Viewers

		createDetailSplitter(pagebook);

		viewer1 = createViewer1(detailSplitter);

		viewer2 = createViewer2(detailSplitter);

		// Page 2: Nothing selected

        emptySelectionLabel = new Label(pagebook, SWT.TOP + SWT.LEFT + SWT.WRAP);

        emptySelectionLabel.setText("Current selection does not support this view"); //

		showPage(PAGE_EMPTY);

		initOrientation();

		// FIXME since this class is not used at the moment we will not have to fix this soon

		// it might also become irrelevant in future uses

		// set the selection if there is an open editor

//		if(EditorUtil.getActiveMultiPageTaxonEditor() != null){

//			selectionChanged(EditorUtil.getActiveMultiPageTaxonEditor(), EditorUtil.getCurrentSelection());

//		}

	}

    private void initOrientation() {

        try {

            orientation = dialogSettings.getInt(getDialogstoreVieworientationKey());

            if ((orientation < 0) || (orientation > 3)) {

            	orientation = VIEW_ORIENTATION_AUTOMATIC;

            }

        } catch (NumberFormatException e) {

        	orientation = VIEW_ORIENTATION_AUTOMATIC;

        }

        // force the update

        currentOrientation = -1;

        setOrientation(orientation);

    }

    /**

     * <p>getDialogstoreVieworientationKey</p>

     *

     * @return a {@link java.lang.String} object.

     */

    protected abstract String getDialogstoreVieworientationKey();

    /**

     * <p>showEmptyPage</p>

     */

    public void showEmptyPage(){

    	showPage(PAGE_EMPTY);

    }

    /**

     * <p>showViewer</p>

     */

    public void showViewer(){

    	showPage(PAGE_VIEWER);

    }

	private void showPage(int page) {

        if (page == PAGE_EMPTY) {

            pagebook.showPage(emptySelectionLabel);

        } else {

            pagebook.showPage(detailSplitter);

        }

    }

	private void addResizeListener(Composite parent) {

		parent.addControlListener(new ControlListener() {

			public void controlMoved(ControlEvent e) {

			}

			public void controlResized(ControlEvent e) {

				computeOrientation();

			}

		});

	}

	void computeOrientation() {

		saveSplitterRatio();

		dialogSettings.put(getDialogstoreVieworientationKey(), orientation);

		if (orientation != VIEW_ORIENTATION_AUTOMATIC) {

			setOrientation(orientation);

		}

		else {

			if (orientation == VIEW_ORIENTATION_SINGLE)

				return;

			Point size= parent.getSize();

			if (size.x != 0 && size.y != 0) {

				if (size.x > size.y)

					setOrientation(VIEW_ORIENTATION_HORIZONTAL);

				else

					setOrientation(VIEW_ORIENTATION_VERTICAL);

			}

		}

	}

	private void saveSplitterRatio() {

		if (detailSplitter != null && ! detailSplitter.isDisposed()) {

	        int[] weigths = detailSplitter.getWeights();

	        int ratio = (weigths[0] * 1000) / (weigths[0] + weigths[1]);

			String key= getDialogStoreRatioKey() + currentOrientation;

	        dialogSettings.put(key, ratio);

		}

	}

    /**

     * <p>getDialogStoreRatioKey</p>

     *

     * @return a {@link java.lang.String} object.

     */

    protected abstract String getDialogStoreRatioKey();

	void setOrientation(int orientation) {

        if (currentOrientation != orientation) {

            if ((getViewer1() != null) 

            	&& !getViewer1().getControl().isDisposed() 

            	&& (detailSplitter != null) 

            	&& !detailSplitter.isDisposed()) {

            	if (orientation == VIEW_ORIENTATION_SINGLE) {

                    setShowViewer2(false);

                } else {

                    if (currentOrientation == VIEW_ORIENTATION_SINGLE) {

                    	setShowViewer2(true);

                    }

                    boolean horizontal = orientation == VIEW_ORIENTATION_HORIZONTAL;

                    detailSplitter.setOrientation(horizontal ? SWT.HORIZONTAL

                                                                     : SWT.VERTICAL);

                }

                detailSplitter.layout();

            }

            updateCheckedState();

            currentOrientation = orientation;

			restoreSplitterRatio();

        }

    }

	/**

	 * @param show

	 */

	private void setShowViewer2(boolean show) {

		showViewer2 = show;

		showOrHideViewer2();		

	}

	/**

	 * 

	 */

	private void showOrHideViewer2() {

        if (showViewer2) {

        	detailSplitter.setMaximizedControl(null);

        } else {

        	detailSplitter.setMaximizedControl(getViewer1().getControl());

        }

	}

	private void restoreSplitterRatio() {

		String ratio= dialogSettings.get(getDialogStoreRatioKey() + currentOrientation);

		if (ratio == null)

			return;

		int intRatio= Integer.parseInt(ratio);

		detailSplitter.setWeights(new int[] {intRatio, 1000 - intRatio});

	}

	private void updateCheckedState() {

//		for (int i= 0; i < fToggleOrientationActions.length; i++) {

//			fToggleOrientationActions[i].setChecked(fOrientation == fToggleOrientationActions[i].getOrientation());

//		}

	}

	/**

	 * <p>createViewer1</p>

	 *

	 * @param parent a {@link org.eclipse.swt.widgets.Composite} object.

	 * @return a {@link org.eclipse.jface.viewers.Viewer} object.

	 */

	protected abstract Viewer createViewer1(Composite parent);

	/**

	 * <p>createViewer2</p>

	 *

	 * @param parent a {@link org.eclipse.swt.widgets.Composite} object.

	 * @return a {@link org.eclipse.jface.viewers.Viewer} object.

	 */

	protected abstract Viewer createViewer2(Composite parent);

	/**

	 * @param pagebook2

	 */

	private void createDetailSplitter(Composite parent) {

		detailSplitter = new SashForm(parent, SWT.HORIZONTAL);

	}

	/* (non-Javadoc)

	 * @see org.eclipse.ui.part.WorkbenchPart#dispose()

	 */

	/** {@inheritDoc} */

	@Override

	public void dispose() {

		selectionService.removeSelectionListener(this);

		selectionService.removePostSelectionListener(this);

		super.dispose();

	}

	/**

	 * <p>Getter for the field <code>viewer1</code>.</p>

	 *

	 * @return a {@link org.eclipse.jface.viewers.Viewer} object.

	 */

	protected Viewer getViewer1() {

		return viewer1;

	}

	/**

	 * <p>Getter for the field <code>viewer2</code>.</p>

	 *

	 * @return a {@link org.eclipse.jface.viewers.Viewer} object.

	 */

	protected Viewer getViewer2() {

		return viewer2;

	}

}