#include <math.h>

#include "SDL.h"
#include "SDL_opengl.h"

#include "glpong3d.h"
#include "paddle.h"

static GLuint paddle_texture;

void
GLPong_PaddleDraw(const Paddle_t * paddle) {
	glLoadIdentity();
	glBindTexture(GL_TEXTURE_2D, paddle_texture);
	glEnable(GL_TEXTURE_2D);
	glColor3f(paddle->r, paddle->g, paddle->b);
	glTranslatef(paddle->coord.x + (paddle->w / 2), paddle->coord.y + (paddle->h / 2), paddle->coord.z);
	glBegin(GL_QUADS);
		glTexCoord2f(0.168f, 1.0f); glVertex2f(paddle->w / 2, paddle->h / 2);	/* Upper Right */
		glTexCoord2f(0.832f, 1.0f); glVertex2f(-paddle->w / 2, paddle->h / 2);	/* Upper Left  */
		glTexCoord2f(0.832f, 0.0f); glVertex2f(-paddle->w / 2, -paddle->h / 2);	/* Lower Left */
		glTexCoord2f(0.168f, 0.0f); glVertex2f(paddle->w / 2, -paddle->h / 2);	/* Lower Right */
	glEnd();
	glDisable(GL_TEXTURE_2D);

#ifdef DEBUG
	/* Lower Left */
	glLoadIdentity();
	glColor3f(0.0f, 0.0f, 1.0f);
	glTranslatef(paddle->coord.x, paddle->coord.y, paddle->coord.z);
	glBegin(GL_POINTS);
		glVertex3f(0.0f, 0.0f, 0.0f);
	glEnd();
	/* Lower Right */
	glLoadIdentity();
	glColor3f(1.0f, 0.0f, 0.0f);
	glTranslatef(paddle->coord.x + paddle->w, paddle->coord.y, paddle->coord.z);
	glBegin(GL_POINTS);
		glVertex3f(0.0f, 0.0f, 0.0f);
	glEnd();
	/* Top Right */
	glLoadIdentity();
	glTranslatef(paddle->coord.x + paddle->w, paddle->coord.y + paddle->h, paddle->coord.z);
	glBegin(GL_POINTS);
		glVertex3f(0.0f, 0.0f, 0.0f);
	glEnd();
	/* Top Left */
	glLoadIdentity();
	glTranslatef(paddle->coord.x, paddle->coord.y + paddle->h, paddle->coord.z);
	glBegin(GL_POINTS);
		glVertex3f(0.0f, 0.0f, 0.0f);
	glEnd();
	/* Center */
	glLoadIdentity();
	glColor3f(0.0f, 1.0f, 0.0f);
	glTranslatef(paddle->coord.x + paddle->w / 2.0f, paddle->coord.y + paddle->h / 2.0f, paddle->coord.z);
	glBegin(GL_POINTS);
		glVertex3f(0.0f, 0.0f, 0.0f);
	glEnd();
#endif
}

void
GLPong_PaddleInit(Paddle_t * paddle, GLfloat z, GLuint texture) {
	paddle->w = 0.66f;
	paddle->h = 0.5f;
	paddle->coord.x = paddle->w / 2.0f;
	paddle->coord.y = paddle->h / 2.0f;
	paddle->coord.z = z;
	paddle->r = 1.0f;
	paddle->g = 1.0f;
	paddle->b = 1.0f;
	
	paddle_texture = texture;
}

void
GLPong_PaddleMove(Paddle_t * paddle, GLfloat x, GLfloat y) {
	GLfloat old_x = paddle->coord.x;
	GLfloat old_y = paddle->coord.y;
	GLfloat mouse_x;
	GLfloat mouse_y;

	/* clamp paddle to border */
	if (x <= -1.5f + (paddle->w / 2.0f)) {
		x = -1.5f + (paddle->w / 2.0f);
	} else if (x >= 1.5f - (paddle->w / 2.0f)) {
		x = 1.5f - (paddle->w / 2.0f);
	}

	if (y <= -1.0f + (paddle->h / 2.0f)) {
		y = -1.0f + (paddle->h / 2.0f);
	} else if (y >= 1.0f - (paddle->h / 2.0f)) {
		y = 1.0f - (paddle->h / 2.0f);
	}

	mouse_x = x - (paddle->w / 2.0f);
	mouse_y = -(y + (paddle->h / 2.0f));
	printf("(mouse_x, mouse_y) = (%.3f, %.3f)\n", mouse_x, mouse_y);

	printf("x diff is %f\n", fabs(mouse_x - old_x));

	if (fabs(mouse_x - old_x) > 0.33f / 2.0f) {
		if (mouse_x > old_x) {
			paddle->coord.x += 0.33f / 2.0f;
		} else {
			paddle->coord.x -= 0.33f / 2.0f;
		}
	} else {
		paddle->coord.x = mouse_x;
	}

	printf("y diff is %f\n", fabs(mouse_y - old_y));

	if (fabs(mouse_y - old_y) > 0.25f / 2.0f) {
		if (mouse_y > old_y) {
			paddle->coord.y += 0.25f / 2.0f;
		} else {
			paddle->coord.y -= 0.25f / 2.0f;
		}
	} else {
		paddle->coord.y = mouse_y;
	}
}