package org.jzy3d.chart;

import org.jzy3d.plot3d.rendering.canvas.ICanvas;

import com.jogamp.opengl.GLCapabilities;
import com.jogamp.opengl.GLProfile;

/**
 * {@link Settings} is a singleton that holds general settings that configure
 * Imaging classes instantiation.
 */
public class Settings {
    private Settings() {
        this(detectProfile());
    }

    private Settings(GLProfile glProfile) {
        this.glProfile = glProfile;
        glCapabilities = new GLCapabilities(glProfile);

        // glCapabilities.setAlphaBits(8);
        setHardwareAccelerated(false);

        // TODO Choose here somehow between NewtDisplay & AWTDisplay
        //display = NewtFactory.createDisplay(null);
        //screen = NewtFactory.createScreen(display, 0);
    } 
    
    public static GLProfile detectProfile() {
        if (!(GLProfile.isAvailable(GLProfile.GL2) || GLProfile.isAvailable(GLProfile.GL2ES2))) {
            throw new UnsupportedOperationException("Jzy3d requires OpenGL 2 or OpenGL 2 ES 2");
        }

        if (GLProfile.isAvailable(GLProfile.GL2)) {
            // Preferred profile = GL2
            return GLProfile.get(GLProfile.GL2);
        } else {
            // second option for Android = GL2ES2
            return GLProfile.get(GLProfile.GL2ES2);
        }
    }


    /** Return the single allowed instance of Settings. */
    public static Settings getInstance() {
        if (instance == null) {
            instance = new Settings();
        }
        return instance;
    }

    /**
     * Modifies the acceleration status for all {@link ICanvas.Canvas}
     * instantiations. This doesn't modify the status of canvases that have
     * allready been instantiated.
     */
    public void setHardwareAccelerated(boolean hardwareAccelerated) {
        glCapabilities.setHardwareAccelerated(hardwareAccelerated);
    }

    /** Returns true if hardware acceleration is used for 3d graphics. */
    public boolean isHardwareAccelerated() {
        return glCapabilities.getHardwareAccelerated();
    }

    /** Returns a copy of the current GL2 capabilities. */
    public GLCapabilities getGLCapabilities() {
        return (GLCapabilities) glCapabilities.clone();
    }

    @Override
    public String toString() {
        return "HardwareAcceleration = " + isHardwareAccelerated() + "\n";
    }

    private static Settings instance;

    // members
    private GLCapabilities glCapabilities;

    private GLProfile glProfile;
}