package monkstone.core;

import static processing.core.PConstants.*;

/**
 * The purpose of this class is to enable
 * access to processing pre, draw and post loops in
 * ruby-processing as a regular java library class.
 * Also included background, fill and stroke methods.
 * PConstants should also be available from static import
 * @author Martin Prout
 */
public abstract class AbstractLibrary {

    private final processing.core.PApplet app;

    /**
     * Useful accessors
     */
    public int width, height;

    /**
     *
     * @param app PApplet
     */
    public AbstractLibrary(processing.core.PApplet app) {
        this.app = app;
        this.width = app.width;
        this.height = app.height;
        setActive(true);
    }

    /**
     * Extending classes must implement this gives access to, by reflection,
     * processing PApplet pre loop (called before draw)
     */
    public abstract void pre();

    /**
     * Extending classes must implement this gives access to processing PApplet
     * draw loop
     */
    public abstract void draw();

    /**
     * Extending classes must implement  this gives access to, by reflection,
     * processing PApplet post loop (called after draw)
     */
    public abstract void post();

    private void setActive(boolean active) {
        if (active) {
            this.app.registerMethod("pre", this);
            this.app.registerMethod("draw", this);
            this.app.registerMethod("post", this);
            this.app.registerMethod("dispose", this);
        } else {
            this.app.unregisterMethod("pre", this);
            this.app.unregisterMethod("draw", this);
            this.app.unregisterMethod("post", this);
        }
    }

    /**
     * Simple signature for background hides need to call app
     * @param col
     */
    public void background(int col) {
        this.app.background(col);
    }

    /**
     * Simple signature for fill hides need to call app
     * @param col
     */
    public void fill(int col) {
        this.app.fill(col);
    }

    /**
     * Simple signature for stroke hides need to call app
     * @param col
     */
    public void stroke(int col) {
        this.app.stroke(col);
    }

    /**
     * Access applet if we must
     * @return app PApplet
     */
    public processing.core.PApplet app() {
        return this.app;
    }

    /**
     * required for processing
     */
    public void dispose() {
        setActive(false);
    }
}