#include <OpenGL/gl.h>
#include <GLUT/glut.h>
#include <stdio.h>

int sWidth = 640;
int sHeight = 480;

int freez = 0;

float spin = 0;			// Angle For The Quad

int mouseLastX=0;
int mouseLastY=0;

float yrot = 0;
float xrot = 0;
float xpos = 0;
float zpos = 0;

float zAcc = 0;
float zMax = 0.04f;
float speedAcc = 0.01f;
float slowAcc = 0.0002f;

float playerHigh = 0;

float inMovement = 0;

const float piover180 = 0.0174532925f;


/////////////////////////////////////////// SETUPS

void init (void)
{
	glClearColor (.95,.95,.95,0);
	glShadeModel (GL_SMOOTH);
	glEnable (GL_DEPTH_TEST);
	
	GLfloat light_position[]= {10,20,5,0};
	
	glLightfv(GL_LIGHT0,GL_POSITION,light_position);
	glEnable(GL_LIGHTING);
	glEnable(GL_LIGHT0);
}

void reshape (int w,int h)
{
	glViewport (0,0,w,h);			// Set the size of the render according to the window's size
	
	glMatrixMode (GL_PROJECTION);	// go to the Projection Stack
	glLoadIdentity ();				// Reset The View
	gluPerspective (90,1,1.5,1000);	// set its Persective to Fov=90, Ratio=1, NearClip=1.5, FarClip=1000
	
	glMatrixMode (GL_MODELVIEW);	// go back in the Model Stack
	glLoadIdentity();				// and reset it
}


///////////////////////////////////////////	OBJECTS

void drawGrid (int size, int step)
{
	float x,z;
	glColor3f (.7,.7,.7);
	
	glDisable (GL_LIGHTING);
	
	glBegin (GL_LINES);		
		for (z=-size; z<size; z+=step){
			glVertex3f (-size, 0, z);
			glVertex3f (size, 0, z);
		}
		
		for (x=-size; x<size; x+=step){
			glVertex3f (x ,0, -size);
			glVertex3f (x, 0, size);
		}
	glEnd ();
	
	glEnable (GL_LIGHTING);
}


///////////////////////////////////////////	CONTROLS

void keyboard (unsigned char key, int x, int y)
{
	if(freez == 0){
		if (key == 'a'){  }		// MOVE Left
		if (key == 'd'){  }		// MOVE Right
	
		if (key == 'w' && zAcc < zMax){		// MOVE Forward
			zAcc += speedAcc;
		}else 
		if (key == 's' && zAcc > -zMax){	// MOVE Backward
			zAcc -= speedAcc;
		}
	}
	
	if (key == 'f'){	// FREEZ
		if(freez == 0){ freez = 1;}
		else{ freez = 0; } 
	}
}

void mouseMotion (int x, int y)
{
	if(freez == 0){
		yrot -= ((x-320)-mouseLastX)*0.4f;
		xrot -= ((y-240)-mouseLastY)*0.2f;
	
		if(xrot > 70){ xrot = 70; }
		if(xrot < -70){ xrot = -70; }

		mouseLastX = x-320;
		mouseLastY = y-240;
	}
}

void computeMovements (void)
{
	xpos -= sin( yrot * piover180 ) * zAcc;
	zpos -= cos( yrot * piover180 ) * zAcc;
	
	if(zAcc > slowAcc){
		zAcc -= slowAcc;
		inMovement += (zAcc*0.4f);
		playerHigh = sin(inMovement);
	}else if(zAcc < -slowAcc){
		zAcc += slowAcc;
		inMovement += (zAcc*0.4f);
		playerHigh = sin(inMovement);
	}else{
		zAcc = 0;
		if(playerHigh > 0.005f){
			playerHigh -= 0.005f;
		}else if(playerHigh < - 0.005f){
			playerHigh += 0.005f;
		}else{
			playerHigh = 0;
		}
	}
}


///////////////////////////////////////////	DRAW

void draw (void)
{
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);		// Clear The Screen And The Depth Buffer
	glLoadIdentity();										// Reset The View
	//gluLookAt (0, 5, 5, 0, 5, 0, 0, 1, 0);	// define a viewing transformation
												// (eyePosition) (centerReferencePosition) (directionVector)
	
	glRotatef (-xrot, 1, 0, 0);			// Rotate depending on head's slope
	glRotatef (-yrot, 0, 1, 0);			// Rotate depending on direction player is facing
	glTranslatef(-xpos, playerHigh-10, -zpos);	// Move depending on the player's position
	
	drawGrid (120, 5);
	glRotatef (spin, 0, 1, 0);
	glColor3f (1,1,1);
	glutSolidCube (10);
	
	glutSwapBuffers ();
}

void idle (void)
{
	spin+=0.2f;
	if (spin>360.0){ spin=spin-360;	}
	
	computeMovements();	
	
	glutPostRedisplay ();
}


///////////////////////////////////////////	MAIN

int main (int argc,char**argv)
{	
	glutInit (&argc,argv);
	glutInitDisplayMode (GLUT_SINGLE | GLUT_RGB | GLUT_DEPTH);
	
	glutInitWindowSize (sWidth, sHeight);
	glutInitWindowPosition ((1600/2)-(640/2), (1200/2)-(480/2));
	glutCreateWindow ("XPac3DE v.1");
	
	init ();
	
	glutDisplayFunc (draw);
	glutReshapeFunc (reshape);
	
	glutKeyboardFunc (keyboard);
	glutPassiveMotionFunc (mouseMotion);
	
	glutIdleFunc (idle);
	
	glutMainLoop();
	return 0;
}