/*
 * This file is part of McIDAS-V
 *
 * Copyright 2007-2016
 * Space Science and Engineering Center (SSEC)
 * University of Wisconsin - Madison
 * 1225 W. Dayton Street, Madison, WI 53706, USA
 * https://www.ssec.wisc.edu/mcidas
 * 
 * All Rights Reserved
 * 
 * McIDAS-V is built on Unidata's IDV and SSEC's VisAD libraries, and
 * some McIDAS-V source code is based on IDV and VisAD source code.  
 * 
 * McIDAS-V is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Lesser Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 * 
 * McIDAS-V 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 Public License for more details.
 * 
 * You should have received a copy of the GNU Lesser Public License
 * along with this program.  If not, see http://www.gnu.org/licenses.
 */
package edu.wisc.ssec.mcidasv.ui;

import java.awt.Color;
import java.awt.Component;
import java.awt.Graphics;

import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;

import javax.swing.BorderFactory;
import javax.swing.CellRendererPane;
import javax.swing.JComponent;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.JViewport;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ListSelectionEvent;
import javax.swing.event.TableColumnModelEvent;
import javax.swing.event.TableColumnModelListener;
import javax.swing.table.JTableHeader;
import javax.swing.table.TableCellRenderer;
import javax.swing.table.TableColumn;
import javax.swing.table.TableModel;

public class BetterJTable extends JTable {

    private static final Color EVEN_ROW_COLOR = new Color(241, 245, 250);
    private static final Color TABLE_GRID_COLOR = new Color(0xd9d9d9);

    private static final CellRendererPane CELL_RENDER_PANE = new CellRendererPane();

    public BetterJTable() {
        super();
        init();
    }
    public BetterJTable(TableModel dm) {
        super(dm);
        init();
    }

    private void init() {
//        setAutoResizeMode(JTable.AUTO_RESIZE_OFF);
        setAutoResizeMode(JTable.AUTO_RESIZE_SUBSEQUENT_COLUMNS);
        setTableHeader(createTableHeader());
        getTableHeader().setReorderingAllowed(false);
        setOpaque(false);
        setGridColor(TABLE_GRID_COLOR);
        // turn off grid painting as we'll handle this manually in order to paint
        // grid lines over the entire viewport.
        setShowGrid(false);
    }

    /**
     * Creates a JTableHeader that paints the table header background to the right
     * of the right-most column if neccesasry.
     */
    private JTableHeader createTableHeader() {
        return new JTableHeader(getColumnModel()) {
            @Override protected void paintComponent(Graphics g) {
                super.paintComponent(g);
                // if this JTableHeader is parented in a JViewport, then paint the
                // table header background to the right of the last column if
                // neccessary.
                JViewport viewport = (JViewport) table.getParent();
                if (viewport != null && table.getWidth() < viewport.getWidth()) {
                    int x = table.getWidth();
                    int width = viewport.getWidth() - table.getWidth();
                    paintHeader(g, getTable(), x, width);
                }
            }
        };
    }

    /**
     * Paints the given JTable's table default header background at given
     * x for the given width.
     */
    private static void paintHeader(Graphics g, JTable table, int x, int width) {
        TableCellRenderer renderer = table.getTableHeader().getDefaultRenderer();
        Component component = renderer.getTableCellRendererComponent(
                table, "", false, false, -1, 2);

        component.setBounds(0, 0, width, table.getTableHeader().getHeight());

        ((JComponent)component).setOpaque(false);
        CELL_RENDER_PANE.paintComponent(g, component, null, x, 0,
                width, table.getTableHeader().getHeight(), true);
    }

    @Override public Component prepareRenderer(TableCellRenderer renderer, int row, int column) {
        Component component = super.prepareRenderer(renderer, row, column);
        // if the rendere is a JComponent and the given row isn't part of a
        // selection, make the renderer non-opaque so that striped rows show
        // through.
        if (component instanceof JComponent) {
            ((JComponent)component).setOpaque(getSelectionModel().isSelectedIndex(row));
        }
        return component;
    }

    // Stripe painting Viewport. //////////////////////////////////////////////

    /**
     * Creates a JViewport that draws a striped backgroud corresponding to the
     * row positions of the given JTable.
     */
    public static class StripedViewport extends JViewport {

        private final JTable fTable;

        public StripedViewport(JTable table) {
            fTable = table;
            setOpaque(false);
            initListeners();
        }

        private void initListeners() {
            // install a listener to cause the whole table to repaint when
            // a column is resized. we do this because the extended grid
            // lines may need to be repainted. this could be cleaned up,
            // but for now, it works fine.
            fTable.getColumnModel().addColumnModelListener(new TableColumnModelListener() {
                @Override public void columnMarginChanged(ChangeEvent e) {
                    repaint();
                }

                @Override public void columnAdded(TableColumnModelEvent e) {}

                @Override public void columnRemoved(TableColumnModelEvent e) {}

                @Override public void columnMoved(TableColumnModelEvent e) {}

                @Override public void columnSelectionChanged(ListSelectionEvent e) {}
            });
            PropertyChangeListener listener = createTableColumnWidthListener();
            for (int i = 0; i < fTable.getColumnModel().getColumnCount(); i++) {
                fTable.getColumnModel().getColumn(i).addPropertyChangeListener(listener);
            }
        }

        private PropertyChangeListener createTableColumnWidthListener() {
            return new PropertyChangeListener() {
                public void propertyChange(PropertyChangeEvent evt) {
                    repaint();
                }
            };
        }

        @Override protected void paintComponent(Graphics g) {
            paintStripedBackground(g);
            paintVerticalGridLines(g);
            super.paintComponent(g);
        }

        private void paintStripedBackground(Graphics g) {
            // get the row index at the top of the clip bounds (the first row
            // to paint).
            int rowAtPoint = fTable.rowAtPoint(g.getClipBounds().getLocation());
            // get the y coordinate of the first row to paint. if there are no
            // rows in the table, start painting at the top of the supplied
            // clipping bounds.
            int topY = rowAtPoint < 0
                    ? g.getClipBounds().y : fTable.getCellRect(rowAtPoint,0,true).y;

            // create a counter variable to hold the current row. if there are no
            // rows in the table, start the counter at 0.
            int currentRow = rowAtPoint < 0 ? 0 : rowAtPoint;
            while (topY < g.getClipBounds().y + g.getClipBounds().height) {
                int bottomY = topY + fTable.getRowHeight();
                g.setColor(getRowColor(currentRow));
                g.fillRect(g.getClipBounds().x, topY, g.getClipBounds().width, bottomY);
                topY = bottomY;
                currentRow++;
            }
        }

        private Color getRowColor(int row) {
            return row % 2 == 0 ? EVEN_ROW_COLOR : getBackground();
        }

        private void paintVerticalGridLines(Graphics g) {
            // paint the column grid dividers for the non-existent rows.
            int x = 0;
            for (int i = 0; i < fTable.getColumnCount(); i++) {
                TableColumn column = fTable.getColumnModel().getColumn(i);
                // increase the x position by the width of the current column.
                x += column.getWidth();
                g.setColor(TABLE_GRID_COLOR);
                // draw the grid line (not sure what the -1 is for, but BasicTableUI
                // also does it.
                g.drawLine(x - 1, g.getClipBounds().y, x - 1, getHeight());
            }
        }
    }

    public static JScrollPane createStripedJScrollPane(JTable table) {
        JScrollPane scrollPane =  new JScrollPane(table);
        scrollPane.setViewport(new StripedViewport(table));
        scrollPane.getViewport().setView(table);
        scrollPane.setBorder(BorderFactory.createEmptyBorder());
//        scrollPane.setCorner(JScrollPane.UPPER_RIGHT_CORNER,
//                createCornerComponent(table));
        return scrollPane;
    }

    /**
     * Creates a component that paints the header background for use in a
     * JScrollPane corner.
     */
    private static JComponent createCornerComponent(final JTable table) {
        return new JComponent() {
            @Override
            protected void paintComponent(Graphics g) {
                paintHeader(g, table, 0, getWidth());
            }
        };
    }
}