#define _POSIX_C_SOURCE 200809L
#include <MLV/MLV_all.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <getopt.h>
#include "grid.h"
#include "snake.h"

#define DIFFICULTY 6

void print_help()
{
	printf("Usage: snake2025 [OPTIONS]\n");
	printf("Options:\n");
	printf("  -h, --help       Display this help message\n");
	printf("  -i, --input FILE Load initial grid configuration from FILE\n");
	printf("\n");
	printf("This is a simple snake game. Use the arrow keys to control the snake.\n");
	printf("Press ESC to exit the game.\n");
}

int main(int argc, char *argv[])
{
	FILE *stream;
	char *buf = NULL;
	size_t size_buf = 0;
	int nbl, nbc, i;
	int opt, option_index = 0;
	int loop_count = 0, nb_fruit = 0;
	char *input_file = NULL;
	int width = 640, height = 480;
	MLV_Keyboard_button touche = MLV_KEYBOARD_NONE;
	int initial_size = 0;

	Grid *g;

	static struct option long_options[] = {
		{"help", no_argument, 0, 'h'},
		{"input", required_argument, 0, 'i'},
		{0, 0, 0, 0}};

	Snake *snake = new_snake();
	add_segment(snake, 1, 5);
	add_segment(snake, 1, 4);
	add_segment(snake, 1, 3);
	add_segment(snake, 1, 2);
	add_segment(snake, 1, 1);
	add_segment(snake, 1, 0);
	snake->dir = BOTTOM;

	initial_size += snake->size;

	while ((opt = getopt_long(argc, argv, "hi:", long_options, &option_index)) != -1)
	{
		switch (opt)
		{
		case 'h':
			print_help();
			return 0;
		case 'i':
			input_file = optarg;
			break;
		default:
			fprintf(stderr, "Unknown option. Use -h or --help for usage information.\n");
			return 1;
		}
	}

	if (input_file == NULL)
	{
		input_file = "levels/default";
	}
	stream = fopen(input_file, "r");
	if (!stream)
	{
		fprintf(stderr, "Error: unable to open file\n");
		exit(EXIT_FAILURE);
	}

	nbl = count_nb_lines(stream);
	rewind(stream);
	nbc = getline(&buf, &size_buf, stream);
	if (nbc == -1)
	{
		fprintf(stderr, "Error: malformed file\n");
		exit(EXIT_FAILURE);
	}
	nbc--;

	g = allocate_grid(nbl, nbc);

	copy(buf, g->grid[0]);
	for (i = 1; i < nbl; i++)
	{
		int size_tmp = getline(&buf, &size_buf, stream);
		if (size_tmp != nbc + 1)
		{
			fprintf(stderr, "Error: inconsistent line length\n");
			free(buf);
			fclose(stream);
			exit(EXIT_FAILURE);
		}
		copy(buf, g->grid[i]);
	}

	rewind(stream);
	nb_fruit = count_fruits(stream, g);
	if (nb_fruit == 0)
	{
		fprintf(stderr, "Error: no fruits in the grid\n");
		free(buf);
		fclose(stream);
		exit(EXIT_FAILURE);
	}
	if (nb_fruit == -1)
	{
		fprintf(stderr, "Error: unable to count fruits\n");
		free(buf);
		fclose(stream);
		exit(EXIT_FAILURE);
	}

	free(buf);
	fclose(stream);

	place_snake(g, snake);

	MLV_create_window("SNAKE", "3R-IN1B", width, height);
	MLV_change_frame_rate(24);

	while (
		MLV_get_event(
			&touche, NULL, NULL,
			NULL, NULL,
			NULL, NULL, NULL,
			NULL) == MLV_NONE ||
		touche != MLV_KEYBOARD_ESCAPE)
	{
		Element result;
		MLV_clear_window(MLV_COLOR_BLACK);

		loop_count = (loop_count + 1) % DIFFICULTY;
		if (loop_count == 0)
		{
			result = move_snake(snake, g);

			if (result == WALL || result == SNAKE)
			{
				if (result == WALL)
				{
					MLV_draw_text(width / 2 - 75, height / 2, "Game Over! You hit a wall.", MLV_COLOR_RED);
				}
				else if (result == SNAKE)
				{
					MLV_draw_text(width / 2 - 75, height / 2, "Game Over! You hit yourself.", MLV_COLOR_RED);
				}
				MLV_actualise_window();
				MLV_wait_seconds(3);
				break;
			}
			else if (result == FRUIT)
			{
				Position *tail = snake->segments_list;
				Position *prev = NULL;
				while (tail->next != NULL)
				{
					prev = tail;
					tail = tail->next;
				}
				int dx = tail->x - (prev ? prev->x : tail->x);
				int dy = tail->y - (prev ? prev->y : tail->y);
				add_segment(snake, tail->x + dx, tail->y + dy);
				place_snake(g, snake);
				if (snake->size == initial_size + nb_fruit)
				{
					MLV_draw_text(
						width / 2 - 75, height / 2,
						"You Win! All fruits collected.",
						MLV_COLOR_GREEN);
					MLV_actualise_window();
					MLV_wait_seconds(3);
					break;
				}
			}
		}

		draw_grid(g);
		MLV_actualise_window();

		switch (touche)
		{
		case MLV_KEYBOARD_DOWN:
			if (snake->dir != TOP)
				snake->dir = BOTTOM;
			break;
		case MLV_KEYBOARD_UP:
			if (snake->dir != BOTTOM)
				snake->dir = TOP;
			break;
		case MLV_KEYBOARD_LEFT:
			if (snake->dir != RIGHT)
				snake->dir = LEFT;
			break;
		case MLV_KEYBOARD_RIGHT:
			if (snake->dir != LEFT)
				snake->dir = RIGHT;
			break;
		default:
			break;
		}

		touche = MLV_KEYBOARD_NONE;
		MLV_delay_according_to_frame_rate();
	}

	MLV_free_window();
	free_grid(g);
	free_snake(snake);
	return 0;
}