/*
 *  RapidMiner
 *
 *  Copyright (C) 2001-2011 by Rapid-I and the contributors
 *
 *  Complete list of developers available at our web site:
 *
 *       http://rapid-i.com
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU Affero General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU Affero General Public License for more details.
 *
 *  You should have received a copy of the GNU Affero General Public License
 *  along with this program.  If not, see http://www.gnu.org/licenses/.
 */
package com.rapidminer.gui.tools;

import java.awt.Point;
import java.awt.Rectangle;

import javax.swing.JViewport;
import javax.swing.table.TableColumn;
import javax.swing.table.TableColumnModel;

/**
 * This is a packer class for the extended JTable.
 * 
 * @author Santhosh Kumar, Ingo Mierswa
 */
public class ExtendedJTablePacker {
	
	private boolean distributeExtraArea = true;

	public ExtendedJTablePacker(boolean distributeExtraArea) {
		this.distributeExtraArea = distributeExtraArea;
	}

	private int preferredWidth(ExtendedJTable table, int col) {
		TableColumn tableColumn = table.getColumnModel().getColumn(col);
		int width = (int)table.getTableHeader().getDefaultRenderer().getTableCellRendererComponent(table, tableColumn.getIdentifier() , false, false, -1, col).getPreferredSize().getWidth();

		if(table.getRowCount() != 0) {
			int from = 0;
			int to = table.getRowCount();
			ExtendedJScrollPane scrollPane = (table).getExtendedScrollPane();
			if (scrollPane != null) {
				JViewport viewport = scrollPane.getViewport();
				Rectangle viewRect = viewport.getViewRect();
				from = table.rowAtPoint(new Point(0, viewRect.y));
				from = Math.max(0, from);
				to = table.rowAtPoint(new Point(0, viewRect.y + viewRect.height - 2));
				to = Math.min(to, table.getRowCount());
			}
			
			for (int row = from; row < to; row++) {
				int preferedWidth = (int)table.getCellRenderer(row, col).getTableCellRendererComponent(table, table.getValueAt(row, col), false, false, row, col).getPreferredSize().getWidth();
				width = Math.max(width, preferedWidth);
			}
		}
		
		return width + table.getIntercellSpacing().width;
	}

	public void pack(ExtendedJTable table) {
		if (!table.isShowing())
			//throw new IllegalStateException("Table must be showed in order to pack it.");
			//return silently;
			return;

		if (table.getTableHeader() == null) 
			return;
		
		if (table.getColumnCount() == 0)
			return;

		int width[] = new int[table.getColumnCount()];
		int total = 0;
		for (int col = 0; col<width.length; col++) {
			width[col] = preferredWidth(table, col);
			total += width[col];
		}

		int extra = table.getVisibleRect().width - total;
		if (extra>0) {
			if (distributeExtraArea) {
				int bonus = extra/table.getColumnCount();
				for(int i = 0; i<width.length; i++)
					width[i] += bonus;
				extra -= bonus*table.getColumnCount();
			}
			width[width.length-1] += extra;
		}

		TableColumnModel columnModel = table.getColumnModel();
		for (int col = width.length - 1; col>= 0; col--) {
			TableColumn tableColumn = columnModel.getColumn(col);
			table.getTableHeader().setResizingColumn(tableColumn);
			tableColumn.setWidth(width[col]);
		}
	}
}