// --------------------------------------------------------------------------
//
// Copyright (c) 2003 Thomas D. Marsh. All rights reserved.
//
// "SSC" is free software; you can redistribute it
// and/or use it and/or modify it under the terms of
// the "GNU General Public License" (GPL).
//
// --------------------------------------------------------------------------

#include "game.h"
#include "screen.h"

Game *Game::mInstance = 0;

const unsigned int FRAMERATE = 50, DISP_FACT = 1;

const int FPS_SZ=100;
inline double fps(double wait)
{
	static double times[FPS_SZ], avg;
	static int c=0, i;

	avg = 0;
	c = (c+1) % FPS_SZ;
	times[c] = wait;

	for (i=0; i < FPS_SZ; ++i)
		avg += times[i];

	return 1000 / (avg / FPS_SZ);
};

double mFramerate;


Game::Game()
	: mModel(Model::getInstance()), dt(0),
	  mTime1(SDL_GetTicks()),
	  mTime2(SDL_GetTicks()),
#ifdef WINDOWS
	  mWait(10)
#else
	  mWait(1)
#endif
{
	Global::ship = new Ship(100, 100);
	mModel->setPlayerPos();
	mLevel.setLevel(1);
	mMenuHandler.setController(&mController);
	mPlayHandler.setController(&mController);
	setMode(MENU);
}

void Game::setMode(GameMode mode)
{
	if (mMode == mode) return;

	mMode = mode;

	switch (mMode)
	{
	case PLAY:
		mModel->startGame();
		mLevel.setLevel(1);
		mController.setHandler(&mPlayHandler);
		break;
	case MENU:
		mController.setHandler(&mMenuHandler);
		break;
	}
}

void Game::loop()
{
	while (1)
	{
		if (!mController.isPaused() && (dt > 0))
		{
			mModel->update(dt);
			if (mLevel.completed())
				mLevel++;
		}
		else
			mModel->draw(dt, false);

		mController.poll(dt);
		delay();

		if (mController.wantExit())
		{
			if (mMode == MENU)
				break;
			else setMode(MENU);
		}
	}

	SDL_Quit();
}

static bool speedWarn=true;
void Game::delay()
{
	if (mController.isPaused())
		SDL_Delay(100);
	else SDL_Delay(mWait);

	mTime1 = SDL_GetTicks();
	double delta = mTime1 - mTime2;
	dt = delta * (mController.slowMotion() ? .025 : .05);
	mFramerate = fps(delta);
	mTime2 = SDL_GetTicks();

	if (!mController.isPaused() && (dt > 1.5))
	{
		if (speedWarn && (mFramerate < 50))
		{
			// TODO: add some flashing in-game text with the
			// framerate warning
			fprintf(stderr, "Could not maintain framerate 50 fps! (dt=%.2f)\n", dt);
			speedWarn = false;
		}
		dt = 1.5;
	}

#ifndef WINDOWS
	if (!mController.slowMotion())
	{
		if ((mWait > 1) && dt > 1.1)
			mWait--;
		else if ((mWait < 20) && (dt < .3))
			mWait++;
	}
#endif // WINDOWS
}