#include <SDL.h>

#include "raytracer.h"

#include <iostream>

#include <fstream>

int w = 320;

int h = 200;

Float *render_buffer;

Raytracer rt;

Camera cam;

void load_ply(const char *filename, Material *mat, Float scale)

{

	vector<Vector3> vertices;

	ifstream f(filename);

	string token = "a";

	if (!f.is_open())

	{

		cout << "File not found: " << filename <<endl;

		exit(1);

	}

	// read header

	int vertex_num, face_num;

	while (token != "end_header")

	{

		f >> token;

		if (token == "element")

		{

			f >> token;

			if (token == "vertex")

				f >> vertex_num;

			if (token == "face")

				f >> face_num;

		}

	}

	// read vertices

	Vector3 v;

	while (vertex_num--)

	{

		f >> v.x >> v.y >> v.z;

		v.x = -scale*v.x;

		v.y = scale*v.y - 3.6;

		v.z = -scale*v.z;

		vertices.push_back(v);

	}

	// read faces

	Triangle *face;

	int num, v1, v2, v3;

	while (face_num--)

	{

		f >> num;

		if (num != 3)

		{

			printf("ply error: faces of %d vertices not supported", num);

			return;

		}

		f >> v1 >> v2 >> v3;

		face = new Triangle(vertices.at(v1), vertices.at(v2), vertices.at(v3), mat);

		rt.addshape(face);

	}

	f.close();

}

void update(SDL_Surface *screen)

{

	rt.render(w, h, render_buffer);

	if (SDL_MUSTLOCK(screen))

		if (SDL_LockSurface(screen) < 0)

			return;

	Uint32 *bufp = (Uint32 *)screen->pixels;

	unsigned char c[3];

	for (Float *fd = render_buffer; fd != render_buffer + w*h*3; fd += 3)

	{

		for (int i = 0; i < 3; i++)

		{

			if (fd[i] > 1.0)

				c[i] = 255;

			else

				c[i] = (unsigned char)(fd[i] * 255.0);

		}

		*bufp = SDL_MapRGB(screen->format, c[0], c[1], c[2]);

		bufp++;

	}

	if (SDL_MUSTLOCK(screen))

		SDL_UnlockSurface(screen);

	if (screen->flags & SDL_DOUBLEBUF)

		SDL_Flip(screen);

	else

		SDL_UpdateRect(screen, 0, 0, w, h);

}

int main()

{

	/* initialize SDL */

	SDL_Surface *screen;

	if( SDL_Init(SDL_INIT_VIDEO) < 0 ) {

		fprintf(stderr, "Couldn't initialize SDL: %s\n", SDL_GetError());

		exit(1);

	}

	atexit(SDL_Quit);

	screen = SDL_SetVideoMode(w, h, 32, SDL_SWSURFACE|SDL_DOUBLEBUF|SDL_RESIZABLE);

	if ( screen == NULL ) {

		fprintf(stderr, "Unable to set video mode: %s\n", SDL_GetError());

		exit(1);

	}

	/* initialize raytracer and prepare scene */

	render_buffer = (Float *) malloc(w*h*3*sizeof(Float));

	rt.setThreads(2);

	rt.setMaxDepth(3);

	KdTree top;

	rt.setTop(&top);

	Light light1(Vector3(-5.0, 2.0, 8.0), Colour(0.9, 0.3, 0.6));

	light1.castShadows(false);

	rt.addlight(&light1);

	//Light light2(Vector3(-2.0, 10.0, 2.0), Colour(0.4, 0.6, 0.3));

	//light2.castShadows(false);

	//rt.addlight(&light2);

	Material mat(Colour(0.9, 0.9, 0.9));

	load_ply("../models/dragon/dragon_vrip_res4.ply", &mat, 29);

	rt.setCamera(&cam);

	cam.setEye(Vector3(0,0,10));

	/* build kd-tree */

	top.setMaxDepth(100);

	top.optimize();

	/* loop... */

	SDL_Event event;

	bool quit = false;

	Float roty = 0.0, rotx = 0.0, move = 0.0;

	while (!quit)

	{

		while (SDL_PollEvent(&event))

		{

			switch (event.type) {

				case SDL_VIDEORESIZE:

					w = event.resize.w;

					h = event.resize.h;

					render_buffer = (Float *) realloc(render_buffer, w*h*3*sizeof(Float));

					screen = SDL_SetVideoMode(w, h, 32, SDL_HWSURFACE|SDL_DOUBLEBUF|SDL_RESIZABLE);

					break;

				case SDL_KEYDOWN:

					if (event.key.keysym.sym == SDLK_ESCAPE) {

						quit = true;

						break;

					}

					if (event.key.keysym.sym == SDLK_LEFT) {

						roty = -0.01;

						break;

					}

					if (event.key.keysym.sym == SDLK_RIGHT) {

						roty = +0.01;

						break;

					}

					if (event.key.keysym.sym == SDLK_DOWN) {

						rotx = +0.01;

						break;

					}

					if (event.key.keysym.sym == SDLK_UP) {

						rotx = -0.01;

						break;

					}

					if (event.key.keysym.sym == SDLK_w) {

						move = +0.5;

						break;

					}

					if (event.key.keysym.sym == SDLK_s) {

						move = -0.5;

						break;

					}

					break;

				case SDL_KEYUP:

					if (event.key.keysym.sym == SDLK_LEFT || event.key.keysym.sym == SDLK_RIGHT) {

						roty = 0.0;

						break;

					}

					if (event.key.keysym.sym == SDLK_UP || event.key.keysym.sym == SDLK_DOWN) {

						rotx = 0.0;

						break;

					}

					if (event.key.keysym.sym == SDLK_w || event.key.keysym.sym == SDLK_s) {

							move = 0.0;

							break;

						}

					break;

				case SDL_QUIT:

					quit = true;

			}

		}

		cam.rotate(Quaternion(cos(roty),0,sin(roty),0).normalize());

		cam.rotate(Quaternion(cos(rotx),cam.u[0]*sin(rotx),0,cam.u[2]*sin(rotx)).normalize());

		cam.u.y = 0;

		cam.u.normalize();

		cam.move(move,0,0);

		update(screen);

	}

	free(render_buffer);

}