import java.awt.DisplayMode;
import java.awt.Graphics2D;
import java.awt.GraphicsConfiguration;
import java.awt.GraphicsDevice;
import java.awt.GraphicsEnvironment;
import java.awt.Window;
import java.awt.image.BufferStrategy;
import java.awt.image.BufferedImage;

import javax.swing.JFrame;

public class ScreenManager {

    //video card variable
    private GraphicsDevice vc;
    //give vc access to monitor
    public ScreenManager(){
        GraphicsEnvironment e = GraphicsEnvironment.getLocalGraphicsEnvironment();
        vc = e.getDefaultScreenDevice();
    }
    //get all compatible displayModes(width,height, bit depth)
    public DisplayMode[] getCompatiableDisplayModes(){
        return vc.getDisplayModes();
    }

    //compares DMs passed into vc and see if they match
    public DisplayMode findFirstCompatiableMode(DisplayMode modes[]){
        DisplayMode goodModes[] = vc.getDisplayModes();
        for(int x=0;x<modes.length;x++){
            for (int y=0;y<goodModes.length;y++){
                if (displayModesMatch(modes[x], goodModes[y])){
                    return modes[x];//since they match we can return either
                }
            }
        }
        return null;//should return true above and never this null
    }

    //get current dm
    public DisplayMode getCurrentDisplayMode(){
        return vc.getDisplayMode();
    }

    //checks if two modes match each other
    public boolean displayModesMatch(DisplayMode m1, DisplayMode m2){
        //check resolution
        if(m1.getWidth() != m2.getWidth()|| m1.getHeight() != m2.getWidth()){
            return false;
        }
        //check bi depths
        if (m1.getBitDepth() != DisplayMode.BIT_DEPTH_MULTI && m2.getBitDepth() != DisplayMode.BIT_DEPTH_MULTI && m1.getBitDepth() != m2.getBitDepth()){
            return false;
        }
        //check refresh rates
        if (m1.getRefreshRate() != DisplayMode.REFRESH_RATE_UNKNOWN && m2. getRefreshRate() != DisplayMode.REFRESH_RATE_UNKNOWN && m1.getRefreshRate() != m2.getRefreshRate()){
            return false;
        }
        //if they past tests then they match
        return true;
    }

    public void setFullScreen(DisplayMode dm){
        JFrame f = new JFrame();
        f.setUndecorated(true);
        f.setIgnoreRepaint(true);
        f.setResizable(false);
        vc.setFullScreenWindow(f);

        if(dm != null && vc.isDisplayChangeSupported()){
            try{
                vc.setDisplayMode(dm);
            }catch(Exception ex){
                System.out.println("couldn't set display mode");
            }
        }
        f.createBufferStrategy(2);
    }

    //we will set graphics object equal to this return
    public Graphics2D getGraphics(){
        //stores current full screen in w
        Window w = vc.getFullScreenWindow();
        if(w != null){
        BufferStrategy s = w.getBufferStrategy();
        return (Graphics2D) s.getDrawGraphics();
        }else{
            return null;
        }
    }

    //updates dispay
    public void update(){
        Window w = vc.getFullScreenWindow();
        if(w != null){
            BufferStrategy s = w.getBufferStrategy();
            if(!s.contentsLost()){
                s.show();
            }
        }
    }
    //returns full screen window
    public Window getFullScreenWindow(){
        return vc.getFullScreenWindow();
    }

    public int getWidth(){
        Window w = vc.getFullScreenWindow();
        if(w != null){
            return w.getWidth();
        }else{
            return 0;
        }
    }

    public int getHeight(){
        Window w = vc.getFullScreenWindow();
        if(w != null){
            return w.getHeight();
        }else{
            return 0;
        }
    }

    //exit full screen
    public void restoreScreen(){
        Window w = vc.getFullScreenWindow();
        if (w != null){
            w.dispose();
        }
        vc.setFullScreenWindow(null);
    }

    //create image compatible with monitor. t is transparency
    public BufferedImage createCompatibleImage(int w, int h, int t){
        Window win = vc.getFullScreenWindow();
        if(win != null){
            GraphicsConfiguration gc = win.getGraphicsConfiguration();
            return gc.createCompatibleImage(w, h, t);
        }
        return null;
    }
}