#include "application.h"

#include "config.h"

#include "texturesdl.h"

#include <SDL/SDL_opengl.h>

#include <iostream>
#include <stdexcept>

#include <cmath>

#include <boost/format.hpp>

Application::Application() {
	// Initialize SDL
	if(SDL_Init(SDL_INIT_VIDEO)) {
		throw(std::runtime_error("SDL initialization failed"));
	}
	// Fetch the video info
	const SDL_VideoInfo *info = SDL_GetVideoInfo();
	if(!info) {
		throw(std::runtime_error("SDL info query failed"));
	}
	// The SDL mode-flags
	int flags = SDL_OPENGL;       // OpenGL in SDL
	flags |= SDL_GL_DOUBLEBUFFER; // Double buffering
	flags |= SDL_HWPALETTE;       // Hardware palette
	// Check for hardware surface aviability
	if(info->hw_available) {
		flags |= SDL_HWSURFACE;
	} else {
		flags |= SDL_SWSURFACE;
	}
	// Check for hardware blit ability
	if(info->blit_hw) {
		flags |= SDL_HWACCEL;
	}
	// Setup double buffering
	SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
	
	SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24);
	
	SDL_GL_SetAttribute(SDL_GL_SWAP_CONTROL, 1);
	
	// Get our surface
	surface = SDL_SetVideoMode(Config::window_w, Config::window_h, 32, flags);
	if(!surface) {
		throw(std::runtime_error("Video mode set failed"));
	}

	// Texturing
	glEnable(GL_TEXTURE_2D);
	// Blending
	glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
	glEnable(GL_BLEND);
	// Smooth shading
	glShadeModel(GL_SMOOTH);

	glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
	
	glEnable(GL_POINT_SPRITE);
	glTexEnvi(GL_POINT_SPRITE, GL_COORD_REPLACE, GL_TRUE);
	
	glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_S,GL_CLAMP_TO_EDGE);
	glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_WRAP_T,GL_CLAMP_TO_EDGE);
	
	glClearColor(0, 0, 0, 0);
	glClearDepth(1);
	
	please_quit = false;
}

Application::~Application() {
	
}

void Application::run() {
	paused = false;
	
	font = new FTPixmapFont("fonts/VeraMono.ttf");
	font->FaceSize(12);
	background = new TextureSDL("textures/background.png");
	
	lasttick = SDL_GetTicks();
	
	while(1) {
		SDL_Event event;
		while(SDL_PollEvent(&event)) {
			if(event.type == SDL_QUIT) {
				break;
			} else if(event.type == SDL_KEYDOWN) {
				event_keypress(event.key.keysym.sym);
			}
		}

		if(please_quit) {
			return;
		}
		
		unsigned int tick = SDL_GetTicks();
		lasttick = tick;
		
		main_loop(tick);
		
		//SDL_Delay(10);
	}
}

void Application::main_loop(unsigned int tick) {
	if(!paused) {
		stage->update();
	}
	
	glClearColor(0, 0, 0, 0);
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
	
	glViewport(0, 0, Config::window_w, Config::window_h);
	
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	float xo = float(Config::window_w)/float(Config::window_h)/2.5 - 0.5;
	glOrtho(-xo, 1 + xo, 0, 0.8, 0, 10);
	
	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();
	
	glBindTexture(GL_TEXTURE_2D, background->tex());
	glBegin(GL_QUADS);
		glTexCoord2f(0, 1);
		glVertex2f(-1.9/9.0, 0);
		glTexCoord2f(0, 0);
		glVertex2f(-1.9/9.0, 0.8);
		glTexCoord2f(1, 0);
		glVertex2f(10.9/9.0, 0.8);
		glTexCoord2f(1, 1);
		glVertex2f(10.9/9.0, 0);
	glEnd();
	
	glDisable(GL_TEXTURE_2D);
	glColor4f(1, 1, 0, 1);
	
	if(tick - lastframes >= 1000) {
		fps = (float)frames * ((float)(tick - lastframes) / 1000.0f);
		frames = 1;
		lastframes = tick;
	} else {
		frames++;
	}
	
	glRasterPos2f(Config::fps_x, Config::fps_y);
	font->Render((boost::format("FPS: %.2f") % fps).str().c_str());
	
	float v_x = Config::window_w * (Config::viewport_x + xo) / (1 + 2 * xo);
	float v_y = Config::window_h * Config::viewport_y;
	float v_w = Config::window_h * Config::viewport_w;
	float v_h = Config::window_h * Config::viewport_h;
	
	glViewport(
		v_x - Config::viewport_overscan,
		v_y - Config::viewport_overscan,
		v_w + Config::viewport_overscan * 2,
		v_h + Config::viewport_overscan * 2);
	glScissor(v_x, v_y, v_w, v_h);
	glEnable(GL_SCISSOR_TEST);
	
	glClearColor(0.2, 0.2, 0.2, 0);
	glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	gluPerspective(45, (float)660 / (float)740, 1, 100);
	
	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();
	
	float f = tick * 0.0005;
	
	gluLookAt(
		5 * sinf(f), 1, 5 * cosf(f),
		0, 0, 0,
		5 * sinf(f), 2, 5 * cosf(f));
	
	glBegin(GL_LINES);
	for(int i = -10; i < 11; i++) {
		if(i % 5 == 0)
			glColor3f(1, 1, 1);
		else
			glColor3f(.5, .5, .5);
		glVertex3f(i, 0, -10);
		glVertex3f(i, 0, 10);
		glVertex3f(-10, 0, i);
		glVertex3f(10, 0, i);
	}
	glEnd();
	
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	glOrtho(
		-float(Config::viewport_overscan) / float(v_w),
		1.0 + float(Config::viewport_overscan) / float(v_w),
		-float(Config::viewport_overscan) / float(v_w),
		Config::viewport_aspect + float(Config::viewport_overscan) / float(v_w),
		0, 10);
	
	glMatrixMode(GL_MODELVIEW);
	glLoadIdentity();
	
	stage->draw();
	
	glDisable(GL_SCISSOR_TEST);
	
	SDL_GL_SwapBuffers();
}

void Application::quit() {
	please_quit = true;
}

void Application::event_keypress(SDLKey key) {
	switch(key) {
		case SDLK_ESCAPE:
			quit();
			break;
		case SDLK_SPACE:
			paused = !paused;
			lasttick = SDL_GetTicks();
			break;
		default:
			break;
	}
}