/*******************************************************************************
 * Copyright (c) 2013 IBM Corporation 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:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.e4.tools.event.spy.ui;

import java.util.ArrayList;
import java.util.List;

import org.eclipse.e4.tools.event.spy.model.CapturedEvent;
import org.eclipse.e4.tools.event.spy.model.CapturedEventTreeSelection;
import org.eclipse.e4.tools.event.spy.model.ItemToFilter;
import org.eclipse.e4.tools.event.spy.model.Parameter;
import org.eclipse.e4.tools.event.spy.util.ParameterFormatter;
import org.eclipse.swt.SWT;
import org.eclipse.swt.events.MouseEvent;
import org.eclipse.swt.events.MouseListener;
import org.eclipse.swt.events.TreeEvent;
import org.eclipse.swt.events.TreeListener;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Tree;
import org.eclipse.swt.widgets.TreeColumn;
import org.eclipse.swt.widgets.TreeItem;


public class CapturedEventTree {

	public interface SelectionListener {
		void selectionChanged(CapturedEventTreeSelection selection);
	}

	private final Tree tree;

	private SelectionListener selectionListener;

	private final List<ItemToFilter> columns = new ArrayList<ItemToFilter>();


	/* Layout scheme:
	 *
	 *  +-- parent---------------+
	 *  |                        |
	 *  |         Tree           |
	 *  |                        |
	 *  +------------------------+
	 *
	 * */

	public CapturedEventTree(Composite parent) {
		tree = new Tree(parent, SWT.BORDER | SWT.H_SCROLL | SWT.V_SCROLL | SWT.FULL_SELECTION);
		tree.setHeaderVisible(true);
		tree.setLinesVisible(true);

		TreeColumn column = new TreeColumn(tree, SWT.LEFT);
		column.setText(ItemToFilter.Topic.toString());
		column.setWidth(350);
		columns.add(ItemToFilter.Topic);

		column = new TreeColumn(tree, SWT.LEFT);
		column.setText(ItemToFilter.Publisher.toString());
		column.setWidth(150);
		columns.add(ItemToFilter.Publisher);

		column = new TreeColumn(tree, SWT.LEFT);
		column.setText(ItemToFilter.ChangedElement.toString());
		column.setWidth(150);
		columns.add(ItemToFilter.ChangedElement);

		addTreeEventListeners();
	}

	@SuppressWarnings("unchecked")
	private void addTreeEventListeners() {
		tree.addTreeListener(new TreeListener() {
			public void treeExpanded(TreeEvent e) {
				TreeItem item = (TreeItem) e.item;
				TreeItem paramItem = item.getItem(0);
				if (paramItem.getText().length() == 0) {
					for (Parameter param: (List<Parameter>) paramItem.getData()) {
						if (paramItem == null) {
							paramItem = new TreeItem(item, SWT.NONE);
						}
						paramItem.setText(ParameterFormatter.toString(param));
						paramItem = null;
					}
				}

			}
			public void treeCollapsed(TreeEvent e) {
			}
		});

		tree.addMouseListener(new MouseListener() {
			public void mouseUp(MouseEvent e) {
			}
			public void mouseDoubleClick(MouseEvent e) {

			}
			public void mouseDown(MouseEvent e) {
				TreeItem[] items = tree.getSelection();
				if (items == null || items.length == 0) {
					return;
				}
				int selectedItemIndex = -1;
				for (int i=0; i<columns.size(); i++) {
					Rectangle rec = items[0].getBounds(i);
					if (e.x >= rec.x && e.x <= rec.x + rec.width) {
						selectedItemIndex = i;
						break;
					}
				}
				if (selectedItemIndex >= 0 && selectionListener != null) {
					String selection = items[0].getText(selectedItemIndex);
					if (selection.length() != 0) {
						selectionListener.selectionChanged(new CapturedEventTreeSelection(selection,items[0].getItemCount() == 0));
					}
				}
			}
		});
	}

	public void addEvent(CapturedEvent event) {
		TreeItem item = new TreeItem(tree, SWT.NONE);

		item.setText(columns.indexOf(ItemToFilter.Topic), event.getTopic());
		item.setText(columns.indexOf(ItemToFilter.Publisher), event.getPublisherClassName());
		item.setText(columns.indexOf(ItemToFilter.ChangedElement), event.getChangedElementClassName());

		if (event.hasParameters()) {
			item = new TreeItem(item, SWT.NONE);
			item.setData(event.getParameters());
		}
	}

	public void setSelectionListener(SelectionListener selectionListener) {
		this.selectionListener = selectionListener;
	}

	public Control getControl() {
		return tree;
	}

	public void removeAll() {
		tree.removeAll();
	}
}