/*
 * Copyrights     : CNRS
 * Author         : Oleg Lodygensky
 * Acknowledgment : XtremWeb-HEP is based on XtremWeb 1.8.0 by inria : http://www.xtremweb.net/
 * Web            : http://www.xtremweb-hep.org
 * 
 *      This file is part of XtremWeb-HEP.
 *
 *    XtremWeb-HEP is free software: you can redistribute it and/or modify
 *    it under the terms of the GNU General Public License as published by
 *    the Free Software Foundation, either version 3 of the License, or
 *    (at your option) any later version.
 *
 *    XtremWeb-HEP 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 General Public License for more details.
 *
 *    You should have received a copy of the GNU General Public License
 *    along with XtremWeb-HEP.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

/**
 * This is provided by Sun Java tutorials
 */

package xtremweb.client.gui;

import java.awt.Color;
import java.awt.Component;
import java.awt.Graphics;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Comparator;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import javax.swing.Icon;
import javax.swing.JLabel;
import javax.swing.JTable;
import javax.swing.SwingConstants;
import javax.swing.event.TableModelEvent;
import javax.swing.event.TableModelListener;
import javax.swing.table.AbstractTableModel;
import javax.swing.table.JTableHeader;
import javax.swing.table.TableCellRenderer;
import javax.swing.table.TableColumnModel;

/**
 * TableSorter is a decorator for TableModels; adding sorting functionality to a
 * supplied TableModel. TableSorter does not store or copy the data in its
 * TableModel; instead it maintains a map from the row indexes of the view to
 * the row indexes of the model. As requests are made of the sorter (like
 * getValueAt(row, col)) they are passed to the underlying model after the row
 * numbers have been translated via the internal mapping array. This way, the
 * TableSorter appears to hold another copy of the table with the rows in a
 * different order.
 * <p/>
 * TableSorter registers itself as a listener to the underlying model, just as
 * the JTable itself would. Events recieved from the model are examined,
 * sometimes manipulated (typically widened), and then passed on to the
 * TableSorter's listeners (typically the JTable). If a change to the model has
 * invalidated the order of TableSorter's rows, a note of this is made and the
 * sorter will resort the rows the next time a value is requested.
 * <p/>
 * When the tableHeader property is set, either by using the setTableHeader()
 * method or the two argument constructor, the table header may be used as a
 * complete UI for TableSorter. The default renderer of the tableHeader is
 * decorated with a renderer that indicates the sorting status of each column.
 * In addition, a mouse listener is installed with the following behavior:
 * <ul>
 * <li>
 * Mouse-click: Clears the sorting status of all other columns and advances the
 * sorting status of that column through three values: {NOT_SORTED, ASCENDING,
 * DESCENDING} (then back to NOT_SORTED again).
 * <li>
 * SHIFT-mouse-click: Clears the sorting status of all other columns and cycles
 * the sorting status of the column through the same three values, in the
 * opposite order: {NOT_SORTED, DESCENDING, ASCENDING}.
 * <li>
 * CONTROL-mouse-click and CONTROL-SHIFT-mouse-click: as above except that the
 * changes to the column do not cancel the statuses of columns that are already
 * sorting - giving a way to initiate a compound sort.
 * </ul>
 * <p/>
 * This is a long overdue rewrite of a class of the same name that first
 * appeared in the swing table demos in 1997.
 * 
 * @author Philip Milne
 * @author Brendon McLean
 * @author Dan van Enckevort
 * @author Parwinder Sekhon
 * @version 2.0 02/27/04
 */

public final class TableSorter extends AbstractTableModel {
	private TableModel tableModel;

	public static final int DESCENDING = -1;
	public static final int NOT_SORTED = 0;
	public static final int ASCENDING = 1;

	private static Directive EMPTY_DIRECTIVE = new Directive(-1, NOT_SORTED);

	public static final Comparator COMPARABLE_COMAPRATOR = new Comparator() {
		public int compare(Object o1, Object o2) {
			return ((Comparable) o1).compareTo(o2);
		}
	};
	public static final Comparator LEXICAL_COMPARATOR = new Comparator() {
		public int compare(Object o1, Object o2) {
			return o1.toString().compareTo(o2.toString());
		}
	};

	private Row[] viewToModel;
	private int[] modelToView;

	private JTableHeader tableHeader;
	private final MouseListener mouseListener;
	private final TableModelListener tableModelListener;
	private final Map columnComparators = new HashMap();
	private final List sortingColumns = new ArrayList();

	public TableSorter() {
		this.mouseListener = new MouseHandler();
		this.tableModelListener = new TableModelHandler();
	}

	public TableSorter(TableModel tableModel) {
		this();
		setTableModel(tableModel);
	}

	public TableSorter(TableModel tableModel, JTableHeader tableHeader) {
		this();
		setTableHeader(tableHeader);
		setTableModel(tableModel);
	}

	private void clearSortingState() {
		viewToModel = null;
		modelToView = null;
	}

	public TableModel getTableModel() {
		return tableModel;
	}

	public void setTableModel(TableModel tableModel) {
		if (this.tableModel != null) {
			this.tableModel.removeTableModelListener(tableModelListener);
		}

		this.tableModel = tableModel;
		if (this.tableModel != null) {
			this.tableModel.addTableModelListener(tableModelListener);
		}

		clearSortingState();
		fireTableStructureChanged();
	}

	public JTableHeader getTableHeader() {
		return tableHeader;
	}

	public void setTableHeader(JTableHeader tableHeader) {
		if (this.tableHeader != null) {
			this.tableHeader.removeMouseListener(mouseListener);
			final TableCellRenderer defaultRenderer = this.tableHeader
					.getDefaultRenderer();
			if (defaultRenderer instanceof SortableHeaderRenderer) {
				this.tableHeader
						.setDefaultRenderer(((SortableHeaderRenderer) defaultRenderer).tableCellRenderer);
			}
		}
		this.tableHeader = tableHeader;
		if (this.tableHeader != null) {
			this.tableHeader.addMouseListener(mouseListener);
			this.tableHeader.setDefaultRenderer(new SortableHeaderRenderer(
					this.tableHeader.getDefaultRenderer()));
		}
	}

	public boolean isSorting() {
		return sortingColumns.size() != 0;
	}

	private Directive getDirective(int column) {
		for (int i = 0; i < sortingColumns.size(); i++) {
			final Directive directive = (Directive) sortingColumns.get(i);
			if (directive.column == column) {
				return directive;
			}
		}
		return EMPTY_DIRECTIVE;
	}

	public int getSortingStatus(int column) {
		return getDirective(column).direction;
	}

	private void sortingStatusChanged() {
		clearSortingState();
		fireTableDataChanged();
		if (tableHeader != null) {
			tableHeader.repaint();
		}
	}

	public void setSortingStatus(int column, int status) {
		final Directive directive = getDirective(column);
		if (directive != EMPTY_DIRECTIVE) {
			sortingColumns.remove(directive);
		}
		if (status != NOT_SORTED) {
			sortingColumns.add(new Directive(column, status));
		}
		sortingStatusChanged();
	}

	protected Icon getHeaderRendererIcon(int column, int size) {
		final Directive directive = getDirective(column);
		if (directive == EMPTY_DIRECTIVE) {
			return null;
		}
		return new Arrow(directive.direction == DESCENDING, size,
				sortingColumns.indexOf(directive));
	}

	private void cancelSorting() {
		sortingColumns.clear();
		sortingStatusChanged();
	}

	public void setColumnComparator(Class type, Comparator comparator) {
		if (comparator == null) {
			columnComparators.remove(type);
		} else {
			columnComparators.put(type, comparator);
		}
	}

	protected Comparator getComparator(int column) {
		final Class columnType = tableModel.getColumnClass(column);
		final Comparator comparator = (Comparator) columnComparators
				.get(columnType);
		if (comparator != null) {
			return comparator;
		}
		if (Comparable.class.isAssignableFrom(columnType)) {
			return COMPARABLE_COMAPRATOR;
		}
		return LEXICAL_COMPARATOR;
	}

	private Row[] getViewToModel() {
		if (viewToModel == null) {
			final int tableModelRowCount = tableModel.getRowCount();
			viewToModel = new Row[tableModelRowCount];
			for (int row = 0; row < tableModelRowCount; row++) {
				viewToModel[row] = new Row(row);
			}

			if (isSorting()) {
				Arrays.sort(viewToModel);
			}
		}
		return viewToModel;
	}

	public int modelIndex(int viewIndex) {
		return getViewToModel()[viewIndex].modelIndex;
	}

	private int[] getModelToView() {
		if (modelToView == null) {
			final int n = getViewToModel().length;
			modelToView = new int[n];
			for (int i = 0; i < n; i++) {
				modelToView[modelIndex(i)] = i;
			}
		}
		return modelToView;
	}

	// TableModel interface methods

	public int getRowCount() {
		return (tableModel == null) ? 0 : tableModel.getRowCount();
	}

	public int getColumnCount() {
		return (tableModel == null) ? 0 : tableModel.getColumnCount();
	}

	@Override
	public String getColumnName(int column) {
		return tableModel.getColumnName(column);
	}

	@Override
	public Class getColumnClass(int column) {
		return tableModel.getColumnClass(column);
	}

	@Override
	public boolean isCellEditable(int row, int column) {
		return tableModel.isCellEditable(modelIndex(row), column);
	}

	public Object getValueAt(int row, int column) {
		return tableModel.getValueAt(modelIndex(row), column);
	}

	@Override
	public void setValueAt(Object aValue, int row, int column) {
		tableModel.setValueAt(aValue, modelIndex(row), column);
	}

	// Helper classes

	private class Row implements Comparable {
		private final int modelIndex;

		public Row(int index) {
			this.modelIndex = index;
		}

		public int compareTo(Object o) {
			final int row1 = modelIndex;
			final int row2 = ((Row) o).modelIndex;

			for (final Iterator it = sortingColumns.iterator(); it.hasNext();) {
				final Directive directive = (Directive) it.next();
				final int column = directive.column;
				final Object o1 = tableModel.getValueAt(row1, column);
				final Object o2 = tableModel.getValueAt(row2, column);

				int comparison = 0;
				// Define null less than everything, except null.
				if ((o1 == null) && (o2 == null)) {
					comparison = 0;
				} else if (o1 == null) {
					comparison = -1;
				} else if (o2 == null) {
					comparison = 1;
				} else {
					comparison = getComparator(column).compare(o1, o2);
				}
				if (comparison != 0) {
					return directive.direction == DESCENDING ? -comparison
							: comparison;
				}
			}
			return 0;
		}
	}

	private class TableModelHandler implements TableModelListener {
		public void tableChanged(TableModelEvent e) {
			// If we're not sorting by anything, just pass the event along.
			if (!isSorting()) {
				clearSortingState();
				fireTableChanged(e);
				return;
			}

			// If the table structure has changed, cancel the sorting; the
			// sorting columns may have been either moved or deleted from
			// the model.
			if (e.getFirstRow() == TableModelEvent.HEADER_ROW) {
				cancelSorting();
				fireTableChanged(e);
				return;
			}

			// We can map a cell event through to the view without widening
			// when the following conditions apply:
			//
			// a) all the changes are on one row (e.getFirstRow() ==
			// e.getLastRow()) and,
			// b) all the changes are in one column (column !=
			// TableModelEvent.ALL_COLUMNS) and,
			// c) we are not sorting on that column (getSortingStatus(column) ==
			// NOT_SORTED) and,
			// d) a reverse lookup will not trigger a sort (modelToView != null)
			//
			// Note: INSERT and DELETE events fail this test as they have column
			// == ALL_COLUMNS.
			//
			// The last checks if modelToView is already allocated. 
			// If we don't do this check; sorting can become
			// a performance bottleneck for applications where cells
			// change rapidly in different parts of the table. If cells
			// change alternately in the sorting column and then outside of
			// it this class can end up re-sorting on alternate cell updates -
			// which can be a performance problem for large tables. The last
			// clause avoids this problem.
			final int column = e.getColumn();
			if ((e.getFirstRow() == e.getLastRow())
					&& (column != TableModelEvent.ALL_COLUMNS)
					&& (getSortingStatus(column) == NOT_SORTED)
					&& (modelToView != null)) {
				final int viewIndex = getModelToView()[e.getFirstRow()];
				fireTableChanged(new TableModelEvent(TableSorter.this,
						viewIndex, viewIndex, column, e.getType()));
				return;
			}

			// Something has happened to the data that may have invalidated the
			// row order.
			clearSortingState();
			fireTableDataChanged();
			return;
		}
	}

	private class MouseHandler extends MouseAdapter {
		@Override
		public void mouseClicked(MouseEvent e) {
			final JTableHeader h = (JTableHeader) e.getSource();
			final TableColumnModel columnModel = h.getColumnModel();
			final int viewColumn = columnModel.getColumnIndexAtX(e.getX());
			final int column = columnModel.getColumn(viewColumn)
					.getModelIndex();
			if (column != -1) {
				int status = getSortingStatus(column);
				if (!e.isControlDown()) {
					cancelSorting();
				}
				// Cycle the sorting states through {NOT_SORTED, ASCENDING,
				// DESCENDING} or
				// {NOT_SORTED, DESCENDING, ASCENDING} depending on whether
				// shift is pressed.
				status = status + (e.isShiftDown() ? -1 : 1);
				status = ((status + 4) % 3) - 1; // signed mod, returning {-1,
													// 0, 1}
				setSortingStatus(column, status);
			}
		}
	}

	private static class Arrow implements Icon {
		private final boolean descending;
		private final int size;
		private final int priority;

		public Arrow(boolean descending, int size, int priority) {
			this.descending = descending;
			this.size = size;
			this.priority = priority;
		}

		public void paintIcon(Component c, Graphics g, int x, int y) {
			final Color color = c == null ? Color.GRAY : c.getBackground();
			// In a compound sort, make each succesive triangle 20%
			// smaller than the previous one.
			final int dx = (int) ((size / 2) * Math.pow(0.8, priority));
			final int dy = descending ? dx : -dx;
			y = y + ((5 * size) / 6) + (descending ? -dy : 0);
			final int shift = descending ? 1 : -1;
			g.translate(x, y);

			// Right diagonal.
			g.setColor(color.darker());
			g.drawLine(dx / 2, dy, 0, 0);
			g.drawLine(dx / 2, dy + shift, 0, shift);

			// Left diagonal.
			g.setColor(color.brighter());
			g.drawLine(dx / 2, dy, dx, 0);
			g.drawLine(dx / 2, dy + shift, dx, shift);

			// Horizontal line.
			if (descending) {
				g.setColor(color.darker().darker());
			} else {
				g.setColor(color.brighter().brighter());
			}
			g.drawLine(dx, 0, 0, 0);

			g.setColor(color);
			g.translate(-x, -y);
		}

		public int getIconWidth() {
			return size;
		}

		public int getIconHeight() {
			return size;
		}
	}

	private class SortableHeaderRenderer implements TableCellRenderer {
		private final TableCellRenderer tableCellRenderer;

		public SortableHeaderRenderer(TableCellRenderer tableCellRenderer) {
			this.tableCellRenderer = tableCellRenderer;
		}

		public Component getTableCellRendererComponent(JTable table,
				Object value, boolean isSelected, boolean hasFocus, int row,
				int column) {
			final Component c = tableCellRenderer
					.getTableCellRendererComponent(table, value, isSelected,
							hasFocus, row, column);
			if (c instanceof JLabel) {
				final JLabel l = (JLabel) c;
				l.setHorizontalTextPosition(SwingConstants.LEFT);
				final int modelColumn = table.convertColumnIndexToModel(column);
				l.setIcon(getHeaderRendererIcon(modelColumn, l.getFont()
						.getSize()));
			}
			return c;
		}
	}

	private static class Directive {
		private final int column;
		private final int direction;

		public Directive(int column, int direction) {
			this.column = column;
			this.direction = direction;
		}
	}
}