import java.awt.*;
import java.awt.event.*;

import javax.swing.*;

/**
 * This is the class that does most of the work in the MosaicDraw program.
 * It creates the two pieces of the program -- the panel and the menu bar -- and
 * makes them available in its getMosaicPanel() and getMenuBar() methods.
 * It attaches a mouse listener to the panel to respond to user mouse actions.
 * It attaches a listener to all the menu items to respond to menu commands from
 * the user.  It contains other instance methods and instance variables to 
 * implement the drawing and all the menu commands.  (Note that this class does
 * not itself represent a GUI component.)  This class depends on MosaicPanel.java.
 */
public class MosaicDrawController {

    private final static int DRAW_TOOL = 0;      // possible values for currentTool
    private final static int ERASE_TOOL = 1;
    private final static int DRAW_3x3_TOOL = 2;
    private final static int ERASE_3x3_TOOL = 3;

    private int currentTool;  // The current tool; this is changed when the
                              // user makes a selection from the Tools menu.

    private int currentRed, currentGreen, currentBlue;  // The current color.
                    // These change when the user selects from the Color menu
                    // They are used whenever a square is painted.  (NOTE:
                    // I am using three integers to represent the color, rather
                    // than a variable of type Color, to make it easier to add
                    // in the random color variation.)

    private MosaicPanel mosaic;     // The panel where the drawing takes place.

    private boolean useRandomness;  // If true, then a small random variation is
                                    // added to the current color whenever a 
                                    // square is painted.  The value is controlled
                                    // by the "Use Randomness" option in the
                                    // Control menu.

    private boolean useSymmetry;    // If true, then whenever a square is painted
                                    // or erased, the three symmetrical squares
                                    // obtained by reflecting the square vertically
                                    // and horizontally are also painted or erased.
                                    // This is controlled by the "Use Symmetry"
                                    // option in the control menu.

    /**
     * Create a controller that uses a MosaicPanel with 40 rows and 40 columns,
     * and in which the preferred size of each square is 12 pixels.
     */
    public MosaicDrawController() {
        this(40,40,12);
    }

    /**
     * Create a controller that uses a MosaicPanel with a specified number of
     * rows and columns and in which the preferred size of each square is 12 pixels.
     */
    public MosaicDrawController(int rows, int columns) {
        this(rows,columns,12);
    }

    /**
     * Create a controller that uses a MosaicPanel with a specified number of
     * rows and columns and in which the preferred size of each square is also
     * given as a parameter.
     */
    public MosaicDrawController(int rows, int columns, int squareSize) {
        mosaic = new MosaicPanel(rows, columns, squareSize, squareSize);
        useRandomness = true;
        useSymmetry = false;
        currentRed = 150;
        currentGreen = 150;
        currentBlue = 225;
        MouseHandler listener = new MouseHandler();
        mosaic.addMouseListener(listener);
        mosaic.addMouseMotionListener(listener);
    }

    /**
     * Returns the MosaicPanel that is used by this controller, so that it
     * can, for example, be used as the content pane of a JFrame.
     */
    public MosaicPanel getMosaicPanel() {
        return mosaic;
    }

    /**
     * Creates and returns a menu bar that contains options that affect the
     * drawing that is done on the MosaicPanel.
     */
    public JMenuBar getMenuBar() {
        JMenuBar menuBar = new JMenuBar();
        MenuHandler listener = new MenuHandler();
        JMenu controlMenu = new JMenu("Control");
        addMenuItem(controlMenu,"Fill",listener);
        addMenuItem(controlMenu,"Clear",listener);
        controlMenu.addSeparator();
        addToggleMenuItem(controlMenu,"Use Randomness",listener,true);
        addToggleMenuItem(controlMenu,"Use Symmetry",listener,false);
        addToggleMenuItem(controlMenu,"Show Grouting",listener,true);
        menuBar.add(controlMenu);
        JMenu colorMenu = new JMenu("Color");
        addMenuItem(colorMenu,"Red",listener);
        addMenuItem(colorMenu,"Green",listener);
        addMenuItem(colorMenu,"Blue",listener);
        addMenuItem(colorMenu,"Cyan",listener);
        addMenuItem(colorMenu,"Magenta",listener);
        addMenuItem(colorMenu,"Yellow",listener);
        addMenuItem(colorMenu,"Gray",listener);
        colorMenu.addSeparator();
        addMenuItem(colorMenu,"Custom Color...",listener);
        menuBar.add(colorMenu);
        JMenu toolMenu = new JMenu("Tools");
        addMenuItem(toolMenu,"Draw",listener);
        addMenuItem(toolMenu,"Erase",listener);
        addMenuItem(toolMenu,"Draw 3x3",listener);
        addMenuItem(toolMenu,"Erase 3x3",listener);
        menuBar.add(toolMenu);
        return menuBar;
    }

    /**
     * Utility method to create a menu item, add a listener to it, and add it to a menu.
     */
    private void addMenuItem(JMenu menu, String command, ActionListener listener) {
        JMenuItem menuItem = new JMenuItem(command);
        menuItem.addActionListener(listener);
        menu.add(menuItem);
    }

    /**
     * Utility method to create a checkbox menu item, add a listener to it, 
     * add it to a menu, and say whether it is initially selected or not.
     */
    private void addToggleMenuItem(JMenu menu, String command, 
            ActionListener listener, boolean selected) {
        JCheckBoxMenuItem menuItem = new JCheckBoxMenuItem(command);
        menuItem.setSelected(selected);
        menuItem.addActionListener(listener);
        menu.add(menuItem);
    }

    /**
     * Erases the square in a specified row and column.  If symmetry is turned
     * on, the three symmetrical squares are also erased.
     */
    private void eraseSquare(int row, int col) {
        mosaic.setColor(row, col, null);
        if (useSymmetry) {
            mosaic.setColor(mosaic.getRowCount() - 1 - row, col, null);
            mosaic.setColor(row, mosaic.getColumnCount() - 1 - col, null);
            mosaic.setColor(mosaic.getRowCount() - 1 - row, mosaic.getColumnCount() - 1 - col, null);
        }
    }

    /**
     * Applies the current drawing color to the square in a given row and column.
     * If randomness is turned on, a random amount is added to the red, green, and 
     * blue components of the drawing color.  If symmetry is turned on, then the
     * three symmetrical squares are also painted.
     */
    private void paintSquare(int row, int col) {
        int r = currentRed;
        int g = currentGreen;
        int b = currentBlue;
        if (useRandomness) {
            if (r < 60)
                r = (int)(60*Math.random());
            else if (r > 255-60)
                r = 255 - (int)(60*Math.random());
            else
                r = r + (int)(60*Math.random() - 30);
            if (g < 60)
                g = (int)(60*Math.random());
            else if (g > 255-60)
                g = 255 - (int)(60*Math.random());
            else
                g = g + (int)(60*Math.random() - 30);
            if (b < 60)
                b = (int)(60*Math.random());
            else if (b > 255-60)
                b = 255 - (int)(60*Math.random());
            else
                b = b + (int)(60*Math.random() - 30);
        }
        mosaic.setColor(row, col, r, g, b);
        if (useSymmetry) {
            mosaic.setColor(mosaic.getRowCount() - 1 - row, col, r, g, b);
            mosaic.setColor(row, mosaic.getColumnCount() - 1 - col, r, g, b);
            mosaic.setColor(mosaic.getRowCount() - 1 - row, mosaic.getColumnCount() - 1 - col, r, g, b);
        }
    }

    /**
     * This method is called when the user clicks the mouse or drags it over the
     * square in the specified row and column.  It takes the appropriate action,
     * depending on which drawing tool is currently selected.
     */
    private void applyCurrentTool(int row, int col) {
        int minrow, mincol, maxrow, maxcol;
        switch (currentTool) {
        case DRAW_TOOL:
            paintSquare(row,col);
            break;
        case ERASE_TOOL:
            eraseSquare(row,col);
            break;
        case DRAW_3x3_TOOL:
            minrow = Math.max(0, row-1);
            maxrow = Math.min(mosaic.getRowCount()-1, row+1);
            mincol = Math.max(0, col-1);
            maxcol = Math.min(mosaic.getColumnCount()-1, col+1);
            for (int i = minrow; i <= maxrow; i++)
                for (int j = mincol; j <= maxcol; j++)
                    paintSquare(i,j);
            break;
        case ERASE_3x3_TOOL:
            minrow = Math.max(0, row-1);
            maxrow = Math.min(mosaic.getRowCount()-1, row+1);
            mincol = Math.max(0, col-1);
            maxcol = Math.min(mosaic.getColumnCount()-1, col+1);
            for (int i = minrow; i <= maxrow; i++)
                for (int j = mincol; j <= maxcol; j++)
                    eraseSquare(i,j);
            break;
        }
    }

    /**
     * An object of type MouseHandler is installed as a mouse listener and mouse
     * motion listener on the MosaicPanel.  It responds to a mousePressed or
     * mouseDragged event on the panel by calling the applyCurrentTool() method
     * for the square that contained the mouse.  (It is declared as a subclass of
     * MouseAdapter so that it doesn't have to include definitions of mouse event
     * methods that are not used in this program.)
     */
    private class MouseHandler extends MouseAdapter {
        public void mousePressed(MouseEvent evt) {
            int row = mosaic.yCoordToRowNumber(evt.getY());
            int col = mosaic.xCoordToColumnNumber(evt.getX());
            if (row >= 0 && row < mosaic.getRowCount() && col >= 0 && col < mosaic.getColumnCount())
                applyCurrentTool(row,col);
        }
        public void mouseDragged(MouseEvent evt) {
            int row = mosaic.yCoordToRowNumber(evt.getY());
            int col = mosaic.xCoordToColumnNumber(evt.getX());
            if (row >= 0 && row < mosaic.getRowCount() && col >= 0 && col < mosaic.getColumnCount())
                applyCurrentTool(row,col);
        }
    } // end class MouseHandler

    /**
     * An object of type MenuHandler is used as the action listener for all
     * the menu items in the menu.  It can tell which item was selected by
     * the user by looking at the action command associated with the ActionEvent.
     * The action command will be the text of the menu item that was selected.
     * (This requires, of course, that all the menu items have different names.)
     * This is a fairly simple way to handle menu items, but not the best or
     * most flexible.
     */
    private class MenuHandler implements ActionListener {
        public void actionPerformed(ActionEvent evt) {
            String command = evt.getActionCommand();
            if (command.equals("Fill")) {  // color every square
                mosaic.setAutopaint(false);
                for (int row = 0; row < mosaic.getRowCount(); row++)
                    for (int col = 0; col < mosaic.getColumnCount(); col++)
                        paintSquare(row,col);
                mosaic.setAutopaint(true);
            }
            else if (command.equals("Clear")) { // clear by filling mosaic with null
                mosaic.fill(null);
            }
            else if (command.equals("Use Randomness")) {
                    // Set the value of useRandomness depending on the menu item's state.
                JCheckBoxMenuItem toggle = (JCheckBoxMenuItem)evt.getSource();
                useRandomness = toggle.isSelected();
            }
            else if (command.equals("Use Symmetry")) {
                    // Set the value of useSymmetry depending on the menu item's state.
                JCheckBoxMenuItem toggle = (JCheckBoxMenuItem)evt.getSource();
                useSymmetry = toggle.isSelected();
            }
            else if (command.equals("Show Grouting")) {
                    // Turn grouting on or off, depending on the menu item's state.
                JCheckBoxMenuItem toggle = (JCheckBoxMenuItem)evt.getSource();
                if (toggle.isSelected())
                    mosaic.setGroutingColor(Color.GRAY);
                else
                    mosaic.setGroutingColor(null);  // Turns grouting off.
            }
            else if (command.equals("Red")) { 
                currentRed = 255;    // Set current drawing color.
                currentGreen = 0;
                currentBlue = 0;
            }
            else if (command.equals("Green")) {
                currentRed = 0;
                currentGreen = 255;
                currentBlue = 0;
            }
            else if (command.equals("Blue")) {
                currentRed = 0;
                currentGreen = 0;
                currentBlue = 255;
            }
            else if (command.equals("Cyan")) {
                currentRed = 0;
                currentGreen = 255;
                currentBlue = 255;
            }
            else if (command.equals("Magenta")) {
                currentRed = 255;
                currentGreen = 0;
                currentBlue = 255;
            }
            else if (command.equals("Yellow")) {
                currentRed = 255;
                currentGreen = 255;
                currentBlue = 0;
            }
            else if (command.equals("Gray")) {
                currentRed = 180;
                currentGreen = 180;
                currentBlue = 180;
            }
            else if (command.equals("Custom Color...")) {
                    // Let the user select the current drawing color using a
                    // standard color chooser dialog.  The color chooser
                    // is initially set to the current drawing color.
                Color c = new Color(currentRed, currentGreen, currentBlue);
                c = JColorChooser.showDialog(mosaic, "Select Drawing Color", c);
                    // If c comes back null, it means that the user canceled
                    // the dialog, so the current drawing color should not change.
                if (c != null) {
                    currentRed = c.getRed();
                    currentGreen = c.getGreen();
                    currentBlue = c.getBlue();
                }
            }
            else if (command.equals("Draw"))
                currentTool = DRAW_TOOL;
            else if (command.equals("Erase"))
                currentTool = ERASE_TOOL;
            else if (command.equals("Draw 3x3"))
                currentTool = DRAW_3x3_TOOL;
            else if (command.equals("Erase 3x3"))
                currentTool = ERASE_3x3_TOOL;
        }
    } // end class MenuHandler

} // end class MosaicDrawController