ScreenModel.java

/*
 * $Id: ScreenModel.java 536 2008-02-19 06:03:27Z weiju $
 * 
 * Created on 11/07/2005
 * Copyright 2005-2008 by Wei-ju Wu
 * This file is part of The Z-machine Preservation Project (ZMPP).
 *
 * ZMPP 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.
 *
 * ZMPP 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 ZMPP.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.zmpp.vm;

import org.zmpp.io.OutputStream;

/**
 * This interface defines the access to the screen model.
 *
 * @author Wei-ju Wu
 * @version 1.0
 */
public interface ScreenModel {

    static final int CURRENT_WINDOW = -3;

    /**
     * Font number for the standard font.
     */
    static final int FONT_NORMAL = 1;

    /**
     * Font number for the character graphics font.
     */
    static final int FONT_CHARACTER_GRAPHICS = 3;

    /**
     * Font number for the fixed pitch font.
     */
    static final int FONT_FIXED = 4;

    static final int TEXTSTYLE_ROMAN = 0;
    static final int TEXTSTYLE_REVERSE_VIDEO = 1;
    static final int TEXTSTYLE_BOLD = 2;
    static final int TEXTSTYLE_ITALIC = 4;
    static final int TEXTSTYLE_FIXED = 8;

    /**
     * Resets the screen model.
     */
    void reset();

    /**
     * Splits the screen into two windows, the upper window will contain
     * linesUpperWindow lines. If linesUpperWindow is 0, the window will be
     * unsplit.
     *
     * @param linesUpperWindow the number of lines the upper window will have
     */
    void splitWindow(int linesUpperWindow);

    /**
     * Sets the active window.
     *
     * @param window the active window
     */
    void setWindow(int window);

    /**
     * Sets the text style.
     *
     * @param style the text style
     */
    void setTextStyle(int style);

    /**
     * Sets the buffer mode.
     *
     * @param flag true if should be buffered, false otherwise
     */
    void setBufferMode(boolean flag);

    /**
     * Version 4/5: If value is 1, erase from current cursor position to the end
     * of the line.
     *
     * @param value the parameter
     */
    void eraseLine(int value);

    /**
     * Clears the window with the specified number to the background color. If
     * window is -1, the screen is unsplit and the area is cleared. If window is
     * -2, the whole screen is cleared, but the splitting status is retained.
     *
     * @param window the window number
     */
    void eraseWindow(int window);

    /**
     * Moves the cursor in the current window to the specified position.
     *
     * @param line the line
     * @param column the column
     * @param the window
     */
    void setTextCursor(int line, int column, int window);

    /**
     * Retrieves the active window's cursor.
     *
     * @return the current window's cursor
     */
    TextCursor getTextCursor();

    /**
     * Sets the paging mode. This is useful if the input stream is a file.
     *
     * @param flag true to enable paging, false to disable
     */
    void setPaging(boolean flag);

    /**
     * Sets the font in the current window.
     *
     * @param fontnumber the font number
     * @boolean the previous font number
     */
    int setFont(int fontnumber);

    /**
     * Sets the background color.
     *
     * @param colornumber the color number
     * @param window the window
     */
    void setBackgroundColor(int colornumber, int window);

    /**
     * Sets the foreground color.
     *
     * @param colornumber a color number
     * @param window the window
     */
    void setForegroundColor(int colornumber, int window);

    /**
     * Forces a redraw.
     */
    void redraw();

    /**
     * Displays the cursor.
     *
     * @param flag true if display, false for clear
     */
    void displayCursor(boolean flag);

    /**
     * Returns the output stream associated with the screen.
     *
     * @return the output stream
     */
    OutputStream getOutputStream();

    /**
     * Wait until this object is initialized.
     */
    void waitInitialized();

    /**
     * Reset the internal pagers.
     */
    void resetPagers();
}