package com.jibberia.gl.asn2;

import org.lwjgl.input.Keyboard;
import org.lwjgl.opengl.Display;
import org.lwjgl.opengl.DisplayMode;
import org.lwjgl.opengl.GL11;
import org.lwjgl.opengl.glu.GLU;

public class Snake {
	private boolean done = false;
	private final String windowTitle = "snakeribbon";
	private DisplayMode displayMode;
	boolean clear = true;
	float camx = 0f, camy=6, camz=18, keyDelta = 0.05f;
	private float cameraRotation = -50;
	private float cameraDistance = 20;
	float sx=0,sy=0,sz=0; // snake
	float id=0.1f, jd=0.015f;
	boolean idGoUp = true, jdGoUp = true;
	private boolean spiral = false;
	private boolean waitForSpace = false;
	
	public static void main(String args[]) {
		Snake app = new Snake();
		app.run();
	}

	public void run() {
		System.out.println("wasd, rf to rotate; space to switch line to circle");
		try {
			init();
			while (!done) {
				updateWindow();
				render();
				Display.update();
			}
			cleanup();
		} catch (Exception e) {
			e.printStackTrace();
			System.exit(0);
		}
	}

	private void init() throws Exception {
		initDisplay();
		initGL();
		rotateCamera();
//		updatePhysics();
//		render();
	}
	private void initDisplay() throws Exception {
		Display.setFullscreen(false);
		DisplayMode d[] = Display.getAvailableDisplayModes();
		for (int i = 0; i < d.length; i++) {
			if (d[i].getWidth() == 800 && d[i].getHeight() == 600 && d[i].getBitsPerPixel() == 32) {
				displayMode = d[i];
				break;
			}
		}
		Display.setDisplayMode(displayMode);
		Display.setTitle(windowTitle);
		Display.create();
	}

	private void initGL() {
		GL11.glMatrixMode(GL11.GL_PROJECTION);
		GL11.glLoadIdentity();
		GLU.gluPerspective(
			45.0f, // field of view
			(float) displayMode.getWidth() / (float) displayMode.getHeight(), // aspect ratio
			0.1f, // near Z clipping plane
			100.0f); // far Z clipping plane

		GL11.glMatrixMode(GL11.GL_MODELVIEW);
		GL11.glEnable(GL11.GL_DEPTH_TEST);
//		GL11.glBlendFunc(GL11.GL_SRC_ALPHA_SATURATE, GL11.GL_ONE);
	}

	private void updateWindow() {
		if (Keyboard.isKeyDown(Keyboard.KEY_ESCAPE)) { // Escape is pressed
			done = true;
		}
		
		boolean r = false;
		if (Keyboard.isKeyDown(Keyboard.KEY_R)) {
			cameraDistance -= keyDelta;
			r = true;
		} 
		if (Keyboard.isKeyDown(Keyboard.KEY_F)) {
			cameraDistance += keyDelta;
			r = true;
		}
		if (Keyboard.isKeyDown(Keyboard.KEY_A)) {
			cameraRotation -= 2*keyDelta;
			r = true;
		}
		if (Keyboard.isKeyDown(Keyboard.KEY_D)) {
			cameraRotation += 2*keyDelta;
			r = true;
		}
		if (Keyboard.isKeyDown(Keyboard.KEY_W)) {
			camy += keyDelta;
			r = true;
		}
		if (Keyboard.isKeyDown(Keyboard.KEY_S)) {
			camy -= keyDelta;
			r = true;
		}
		if(Keyboard.isKeyDown(Keyboard.KEY_SPACE)) {
			waitForSpace = true;
		} else if(waitForSpace) {
			spiral = !spiral;
			waitForSpace = false;
		}
		if(r) rotateCamera();
		
		if (Display.isCloseRequested()) { // Window is closed
			done = true;
		}
		clear = !Keyboard.isKeyDown(Keyboard.KEY_C);
	}
	private void rotateCamera() {
		camx = cameraDistance * (float) Math.sin(Math.toRadians(cameraRotation));
		camz = cameraDistance * (float) Math.cos(Math.toRadians(cameraRotation));
//		System.out.printf("%5.2f, %5.2f, %5.2f\nr: %f d:%f\n:",
//				camx, camy, camz, cameraRotation, cameraDistance);
		render();
	}

	public void render() {
		if (clear) {
//			GL11.glClearColor(1,1,1,1);
			GL11.glClear(GL11.GL_COLOR_BUFFER_BIT | GL11.GL_DEPTH_BUFFER_BIT);
		}
		

		GL11.glMatrixMode(GL11.GL_MODELVIEW);
		GL11.glLoadIdentity();

		GLU.gluLookAt(
				camx, camy, camz,	// eye position
				0f, 0f, 0f,			// target to look at
				0f, 1f, 0f);		// which way is up

		
//		drawAxes();
		
		float steps = 50;
		if(spiral) {
			steps = 360;
//			GL11.glTranslatef(-25, 0, 0);
		} else {
//			float steps = 180;
			GL11.glTranslatef(-steps/2, 0, 0);
		}
			
		float r = 5;
		
		GL11.glBegin(GL11.GL_QUAD_STRIP);
		for(float i=0, j=0; i<steps; i+=id, j+=jd) {
			float c = Math.abs((i/(steps/2))-1f);
			GL11.glColor4f(c*0.8f, c*0.8f, c, c);
			if(spiral) {
				GL11.glVertex3f((float) Math.sin(Math.toRadians(i))*r, (float) (Math.sin((i)) * Math.sin(j)), (float) (Math.cos(Math.toRadians(i))*r)-1);
				GL11.glVertex3f((float) Math.sin(Math.toRadians(i))*r, (float) (Math.sin((i)) * Math.sin(j)), (float) (Math.cos(Math.toRadians(i))*r)+1);
			} else {
				GL11.glVertex3f(i, (float) (Math.sin((i)) * Math.sin(j)), -1);
				GL11.glVertex3f(i, (float) (Math.sin((i)) * Math.sin(j)),  1);
			}
		}
		GL11.glEnd();
	
		if(id > 0.3f) idGoUp = false;
		else if(id < 0.05f) idGoUp = true;
		if(idGoUp )	id += 0.0001f;
		else		id -= 0.0001f;
		
		if(jd > 0.03f) jdGoUp = false;
		else if(jd < 0.001f) jdGoUp = true;
		if(jdGoUp )	jd += 0.0000075f;
		else		jd -= 0.0000075f;
		
//		System.out.printf("%f %f\n", id, jd);
		
		/*
		sx=0;sy=0;sz=0;
		
		GL11.glBegin(GL11.GL_LINE_STRIP);
		
		for(int i=0; i<10; i++) {
			GL11.glVertex3f(sx,sy,sz);
			sx += Math.random();
			sy += Math.random();
			sz += Math.random();
			
			for(int j=0; j<3; j++) {
				float jit = (float) ((float) (Math.random() * 0.4) - 0.2);
				GL11.glVertex3f(sx+jit,sy+jit,sz+jit);
			}
		}
		GL11.glEnd();
		*/
	}

	private void drawAxes() {
        GL11.glLineWidth(1);
        GL11.glBegin(GL11.GL_LINE_STRIP); 
	    	GL11.glVertex3f( -1f, 0f, 0f);        // left
	    	GL11.glVertex3f( 1f, 0f, 0f);         // right
    	GL11.glEnd();
    	GL11.glColor3f(1, 0, 0);
    	GL11.glBegin(GL11.GL_LINE_STRIP); 
	    	GL11.glVertex3f( 0f, -1f, 0f);        // bottom
	    	GL11.glVertex3f( 0f, 1f, 0f);         // top
    	GL11.glEnd(); 
    	GL11.glColor3f(0,1,0);
    	GL11.glBegin(GL11.GL_LINE_STRIP); 
			GL11.glVertex3f( 0f, 0f, -1f);        // far
			GL11.glVertex3f( 0f, 0f, 1f);         // near
		GL11.glEnd(); 
    	GL11.glColor3f(1,1,1);
		GL11.glBegin(GL11.GL_LINE_STRIP); 
			GL11.glVertex3f( -1f, 0f, 1f);        // left near
			GL11.glVertex3f( 1f, 0f, 1f);         // rite near
			GL11.glVertex3f( 1f, 0f, -1f);        // rite far
			GL11.glVertex3f( -1f, 0f, -1f);       // left far
			GL11.glVertex3f( -1f, 0f, 1f);        // left near (close)
		GL11.glEnd();
	}

	private void cleanup() {
		Display.destroy();
	}
}