/*
 * This file is part of the Illarion project.
 *
 * Copyright © 2014 - Illarion e.V.
 *
 * Illarion is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Illarion 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.
 */
package org.illarion.engine;

import javax.annotation.Nonnull;
import javax.annotation.Nullable;
import javax.annotation.concurrent.NotThreadSafe;

/**
 * This is the container that is displaying the game. The implementing class can realize this container in any
 * fitting way. Could be a Swing Window, a native window, a canvas component or a applet.
 *
 * @author Martin Karing <nitram@illarion.org>
 */
@NotThreadSafe
public interface GameContainer {
    /**
     * Get the height of the container.
     *
     * @return the height of the container
     */
    int getHeight();

    /**
     * Get the width of the container.
     *
     * @return the width of the container
     */
    int getWidth();

    /**
     * Get the backing engine that is used to operate the capabilities of the container.
     *
     * @return the backing engine
     * @throws IllegalStateException in case the game was not launched yet
     */
    @Nonnull
    Engine getEngine();

    /**
     * Set the mouse cursor that should be applied to the mouse.
     *
     * @param cursor the cursor to display or {@code null} to revert to the default cursor
     */
    void setMouseCursor(@Nullable MouseCursor cursor);

    /**
     * Calling this function will activate the game, starting the lifecycle of the game,
     * creating the required window and so on.
     *
     * @throws EngineException in case the launch of the application fails
     */
    void startGame() throws EngineException;

    /**
     * Shut the game down.
     */
    void exitGame();

    /**
     * Get the title of the game.
     *
     * @return the games title
     */
    @Nonnull
    String getTitle();

    /**
     * Get the current amount of frames that are rendered per second.
     *
     * @return the current FPS
     */
    int getFPS();

    /**
     * Get the engine diagnostic lines that can be displayed on the screen for debugging.
     *
     * @return the diagnostic lines
     */
    @Nonnull
    CharSequence[] getDiagnosticLines();
}