/*
 * TableSorter.java
 *
 * Copyright (c) 2004-2011 Gregory Kotsaftis
 * gregkotsaftis@yahoo.com
 * http://zeus-jscl.sourceforge.net/
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */

/*
 * The original code was written by 'Sun' and was published
 * at 'java.sun.com' tutorial. All original copyrights (if any) are
 * reserved by the original author.
 * The zeus-jscl copyright above refers only to any modifications
 * made to the original sources.
 * http://java.sun.com/docs/books/tutorial/uiswing/components/table.html#sorting
 */

package gr.zeus.ui.table;

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.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;
import javax.swing.table.TableModel;

/**
 * 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.
 *
 * <p>
 * Modified by Gregory Kotsaftis in order to accept custom icon images
 * instead of just Arrow icon.
 * <p>
 *
 * @author Philip Milne
 * @author Brendon McLean
 * @author Dan van Enckevort
 * @author Parwinder Sekhon
 * @version 2.0 02/27/04
 *
 * @author Gregory Kotsaftis
 * @since 1.50
 */
public class TableSorter extends AbstractTableModel {

    // Greg
    private boolean m_useCustomIcons = false;
    private Icon[] m_customUpIcons = null;
    private Icon[] m_customDownIcons = null;

    protected 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_COMPARATOR = 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 MouseListener mouseListener;
    private TableModelListener tableModelListener;
    private Map columnComparators = new HashMap();
    private 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;
    }


    /**
     * Arrays contains all custom icons with priority order from high to low.
     * Greg
     */
    public void setCustomIcons(Icon[] ups, Icon[] downs)
    {
        m_customUpIcons = ups;
        m_customDownIcons = downs;
        m_useCustomIcons = (m_customUpIcons != null &&
                            m_customUpIcons.length > 0 &&
                            m_customDownIcons != null &&
                            m_customDownIcons.length > 0 &&
                            m_customUpIcons.length == m_customDownIcons.length);
    }


    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);
            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++)
        {
            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)
    {
        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)
    {
        Directive directive = getDirective(column);
        if (directive == EMPTY_DIRECTIVE)
        {
            return null;
        }
        return new Arrow(directive.direction == DESCENDING, size,
                                            sortingColumns.indexOf(directive));
    }


    // Greg
    protected Icon getHeaderRendererCustomIcon(int column)
    {
        Directive directive = getDirective(column);
        if (directive == EMPTY_DIRECTIVE)
        {
            return null;
        }

        if( sortingColumns.indexOf(directive) < m_customUpIcons.length )
        {
            if( directive.direction == DESCENDING )
            {
                return m_customDownIcons[sortingColumns.indexOf(directive)];
            }
            else
            {
                return m_customUpIcons[sortingColumns.indexOf(directive)];
            }
        }
        else
        {
            return null ;
        }
    }


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


    private Row[] getViewToModel()
    {
        if (viewToModel == null)
        {
            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)
        {
            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();
    }


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


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


    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);
    }


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


    // Helper classes

    private class Row implements Comparable {

        private int modelIndex;


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


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

            for (Iterator it = sortingColumns.iterator(); it.hasNext();)
            {
                Directive directive = (Directive) it.next();
                int column = directive.column;
                Object o1 = tableModel.getValueAt(row1, column);
                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 check, for (modelToView != null) is to see 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.
            int column = e.getColumn();
            if (e.getFirstRow() == e.getLastRow()
            && column != TableModelEvent.ALL_COLUMNS
                    && getSortingStatus(column) == NOT_SORTED
                    && modelToView != null)
            {
                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 {


        public void mouseClicked(MouseEvent e)
        {
            JTableHeader h = (JTableHeader) e.getSource();
            TableColumnModel columnModel = h.getColumnModel();
            int viewColumn = columnModel.getColumnIndexAtX(e.getX());
            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 boolean descending;
        private int size;
        private 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)
        {
            Color color = c == null ? Color.GRAY : c.getBackground();
            // In a compound sort, make each succesive triangle 20%
            // smaller than the previous one.
            int dx = (int)(size/2*Math.pow(0.8, priority));
            int dy = descending ? dx : -dx;
            // Align icon (roughly) with font baseline.
            y = y + 5*size/6 + (descending ? -dy : 0);
            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 TableCellRenderer tableCellRenderer;


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


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

    }


    private static class Directive {

        private int column;
        private int direction;


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

}
