#include<stdio.h>
#include<stdlib.h>
#include<unistd.h>
#include<termios.h>
#include <sys/select.h>
#include<signal.h>

#include"input_output.h"
#include"playfield.h"


int difficulty = 200;
static struct termios oldt, newt;
char  * playfield;
char ** horizon;

static volatile char sigint_received = 0;

int main(void)
{

	// set up the terminal for our hacky game....

	static struct termios oldt, newt;
	tcgetattr(STDIN_FILENO, &oldt);
	newt = oldt;
	newt.c_lflag &= ~(ICANON | ECHO);
	tcsetattr(STDIN_FILENO, TCSANOW, &newt);

	// ok done

	int pos = 0;


	unsigned long long int score = 0;

	char input = KEY_DEFAULT;
	int to_place = 0;
	printf("q: end; d: right; a: left\n\n\n");

	while(input != KEY_EXIT && !(EOF_received || sigint_received))
	{
		horizon_drop_one_line(horizon);
		// clear both the cursor and
		// the last enemy
		playfield[pos] = ' ';
		horizon[0][to_place] = ' ';

		if(input == KEY_RIGHT)
		{
			pos++;
			if(pos >= WIDTH)
			{
				pos = 0;
			}
		}
		if(input == KEY_LEFT)
		{
			pos--;
			if(pos < 0)
			{
				pos = WIDTH - 1;
			}
		}
		if(input == KEY_EXIT)
		{
			break;
		}
		clear_screen();
		
		print_horizon(horizon);

		playfield[pos] = CHAR_ME; 
		to_place = (random() & 0xff) % WIDTH;
		horizon[0][to_place] = CHAR_ENEMY;
		put_line(playfield);

		if(horizon[LINES - 1][pos] == CHAR_ENEMY)
		{
			printf("GAME OVER!\nYour score was: %llu\n", score);
			break;
		}
		usleep(difficulty * 1000);
		score++;

		if(!(score % 50))
		{
			difficulty--;
		}
		if(score == 0)
		{
			printf("Congrats. You won the game.\nAnd you have absolutely no life.\nat all.\n");
			break;
		}

		printf("SCORE: %llu\n", score);

		// check this to prevent blocking
		if(EOF_received || sigint_received)
		{
			break;
		}
		input = get_last_key_or_default();
	}

	tcsetattr(STDIN_FILENO, TCSANOW, &oldt);
	return 0;
}

void __attribute__((cold)) handle_sigint(int signum)
{
	sigint_received = 1;
}
void __attribute__((cold)) handle_sigterm(int signum)
{
	printf("\n\nTERMINATED!\n");
	exit(1);

}

/*
Constructor: Add a sighandler for SIGINT and SIGTERM
 */
void __attribute__((constructor)) add_signal_handlers(void)
{
	signal(SIGINT, handle_sigint);
	signal(SIGTERM, handle_sigterm);
}

/*
Destructor: Free memory 
 */
void __attribute__((destructor)) clean(void)
{
	free(playfield);
	delete_horizon(horizon);
	printf("\n");
}

/*
Constructor: create all the data we need
 */
void __attribute__((constructor)) build_playfield(void)
{
	playfield = allocate_playfield(WIDTH);
	build_horizon(&horizon);
}