/*******************************************************************************
 * Copyright (c) 2015 Ericsson
 *
 * 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:
 *   Guy Perron - Initial Implementation
 ******************************************************************************/
package org.eclipse.egerrit.internal.ui.table;

import org.eclipse.egerrit.internal.core.GerritClient;
import org.eclipse.egerrit.internal.model.ChangeInfo;
import org.eclipse.egerrit.internal.model.ChangeMessageInfo;
import org.eclipse.egerrit.internal.ui.table.model.HistoryTableModel;
import org.eclipse.egerrit.internal.ui.table.model.HistoryTableSorter;
import org.eclipse.egerrit.internal.ui.table.model.ITableModel;
import org.eclipse.egerrit.internal.ui.table.provider.HistoryTableMenuBuilder;
import org.eclipse.jface.viewers.TableViewer;
import org.eclipse.jface.viewers.TableViewerColumn;
import org.eclipse.swt.SWT;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Listener;
import org.eclipse.swt.widgets.Table;
import org.eclipse.swt.widgets.TableColumn;

/**
 * This class implements the history table view.
 *
 * @since 1.0
 */
public class UIHistoryTable {

	public static final String HISTORY_TABLE = "historyTable"; //$NON-NLS-1$

	private static final int TABLE_STYLE = SWT.H_SCROLL | SWT.V_SCROLL | SWT.FULL_SELECTION;

	// ------------------------------------------------------------------------
	// Variables
	// ------------------------------------------------------------------------
	private TableViewer fViewer;

	private HistoryTableMenuBuilder dynamicHistoryMenu = new HistoryTableMenuBuilder();

	private GerritClient fGerritClient;

	// ------------------------------------------------------------------------
	// Constructors
	// ------------------------------------------------------------------------

	public UIHistoryTable(GerritClient gerritClient) {
		this.fGerritClient = gerritClient;

	}

	// ------------------------------------------------------------------------
	// Methods
	// ------------------------------------------------------------------------

	public TableViewer createTableViewerSection(Composite aParent) {
		// Create the table viewer
		fViewer = new TableViewer(aParent, TABLE_STYLE);
		fViewer = buildAndLayoutTable(fViewer);

		// Set the content sorter
		HistoryTableSorter.bind(fViewer);
		fViewer.setComparator(new HistoryTableSorter(1)); // sort by date, descending
		//
		fViewer.getTable().addListener(SWT.Paint, initPaintListener());

		return fViewer;

	}

	/**
	 * Listener selecting the first item in the table if the table is not empty when available
	 *
	 * @return
	 */
	private Listener initPaintListener() {
		return new Listener() {

			@Override
			public void handleEvent(Event event) {
				if (fViewer.getTable().getItemCount() > 0) {
					fViewer.getTable().select(0); //initially select the first item in the table
					ChangeMessageInfo message = (ChangeMessageInfo) fViewer.getTable().getSelection()[0].getData();
					ChangeInfo containingChange = (ChangeInfo) message.eContainer();
					//By the time we get here, some of the entries we are trying to show may have already been removed from their parent
					//as part of the loading of the details review (See QueryHelpers.mergeNewInformation()) so we don't want to reveal those.
					if (containingChange != null) {
						fViewer.setSelection(fViewer.getSelection());
						resizeTable(fViewer.getTable());
						fViewer.getTable().removeListener(SWT.Paint, this);
					}
				}
			}
		};
	}

	/**
	 * Adjust the table column according to the text in each column
	 *
	 * @param table
	 */
	private void resizeTable(Table table) {
		//Not resizing the first column since this is an icon for the comments
		for (int index = 1; index < table.getColumnCount(); index++) {
			TableColumn tc = table.getColumn(index);
			tc.pack();
		}
	}

	/**
	 * Create each column for the Conflicts with table
	 *
	 * @param aParent
	 * @param aViewer
	 */
	private TableViewer buildAndLayoutTable(final TableViewer aViewer) {
		final Table table = aViewer.getTable();

		//Get the review table definition
		ITableModel[] tableInfo = HistoryTableModel.values();
		int size = tableInfo.length;
//		logger.debug("Table	Name	Width	Resize Moveable"); //$NON-NLS-1$
		for (int index = 0; index < size; index++) {
			createTableViewerColumn(tableInfo[index]);
		}

		table.setHeaderVisible(true);
		table.setLinesVisible(true);
		table.setData(HISTORY_TABLE);

		dynamicHistoryMenu.addPulldownMenu(fViewer, fGerritClient);

		return aViewer;
	}

	/**
	 * Create each column in the review table list
	 *
	 * @param ConflictWithTableModel
	 * @return TableViewerColumn
	 */
	private TableViewerColumn createTableViewerColumn(ITableModel tableInfo) {
		final TableViewerColumn viewerColumn = new TableViewerColumn(fViewer, SWT.NONE);
		final TableColumn column = viewerColumn.getColumn();
		column.setText(tableInfo.getName());
		column.setWidth(tableInfo.getWidth());
		column.setAlignment(tableInfo.getAlignment());
		column.setResizable(tableInfo.getResize());
		column.setMoveable(tableInfo.getMoveable());
		return viewerColumn;

	}

	/**
	 * return the table viewer
	 *
	 * @return
	 */
	public TableViewer getViewer() {
		return fViewer;
	}

}