/* ************************************************************************** */
/*                                                                            */
/*                                                        :::      ::::::::   */
/*   part2.c                                            :+:      :+:    :+:   */
/*                                                    +:+ +:+         +:+     */
/*   By: tomoron <tomoron@student.42.fr>            +#+  +:+       +#+        */
/*                                                +#+#+#+#+#+   +#+           */
/*   Created: 2024/07/17 23:03:36 by tomoron           #+#    #+#             */
/*   Updated: 2025/12/10 15:08:17 by tomoron          ###   ########.fr       */
/*                                                                            */
/* ************************************************************************** */

#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include "libft/libft.h"

typedef struct s_cords
{
	double x;
	double y;
}	t_coords;

static t_coords parse_line(char *line)
{
	t_coords res;

	res.x = atoi(line);
	while(ft_isdigit(*line))
		line++;
	line++;
	res.y = atoi(line);
	return(res);
}

static int is_point_on_line(t_coords pos, t_coords a, t_coords b)
{
	double cross = (pos.x - a.x) * (b.y - a.y) - (pos.y - a.y) * (b.x - a.x);
	if(cross != 0)
		return(0);
	return(pos.x >= fmin(a.x, b.x) && pos.x <= fmax(a.x, b.x) &&
			pos.y >= fmin(a.y, b.y) && pos.y <= fmax(a.y, b.y));

}


static int is_point_in_poly(t_coords pos, t_coords *poly, int len)
{
	int inside;
	int i;
	t_coords cur[2];
	double intersect;

	inside = 0;
	i = 0;
	while(i < len)
	{
		cur[0] = poly[i];	
		cur[1] = poly[(i + 1) % len];

		if(is_point_on_line(pos, cur[0], cur[1]))
		{
			inside = 1;
			break;
		}

		if((cur[0].y > pos.y) != (cur[1].y > pos.y))
		{
			intersect = ((cur[1].x - cur[0].x) *  (pos.y - cur[0].y)) / (cur[1].y - cur[0].y) + cur[0].x;
			if(pos.x < intersect)
				inside = !inside;
		}
		i++;
	}
	return(inside);
}

static int is_line_in_poly(t_coords p1, t_coords p2, t_coords *poly, int len)
{
	t_coords from;
	t_coords to;

	from.x = fmin(p1.x, p2.x);
	from.y = fmin(p1.y, p2.y);
	to.x = fmax(p1.x, p2.x);
	to.y = fmax(p1.y, p2.y);

	while(from.x <= to.x && from.y <= to.y)
	{
		if(!is_point_in_poly(from, poly, len))
		{
			return(0);
		}
		if(from.x != to.x)		
			from.x++;
		else
			from.y++;
	}
	return(1);
}

static int is_all_in_poly(t_coords p1, t_coords p2, t_coords *poly, int len)
{

	if(!is_line_in_poly(p1,(t_coords){p2.x, p1.y}, poly, len) || 
		!is_line_in_poly((t_coords){p2.x, p1.y}, p2, poly, len) || 
		!is_line_in_poly(p2, (t_coords){p1.x, p2.y}, poly, len) || 
		!is_line_in_poly((t_coords){p1.x, p2.y},p1, poly, len))
		return(0);
	return(1);
}

static long int get_biggest_area(t_coords *co, int len)
{
	int i;
	int j;
	long int max;
	long int tmp;

	i = 0;
	max = 0;
	while(i < len)
	{
		j = i;
		while(++j < len)
		{
			if(i == j)
				continue;
			tmp = ((long)fabs(co[i].x - co[j].x) + 1) * ((long)fabs(co[i].y - co[j].y) + 1);
			if(tmp <= max)
				continue;
			if(!is_point_in_poly((t_coords){co[i].x,co[j].y}, co, len) || !is_point_in_poly((t_coords){co[j].x,co[i].y}, co, len))
				continue;
			if(!is_all_in_poly(co[i], co[j], co, len))
				continue;
			printf("got %ld for %.0f, %.0f to %.0f, %.0f checking points \n", tmp, co[i].x, co[i].y, co[j].x, co[j].y);
			max = tmp;
		}
		i++;
	}
	return(max);
}

long int resolve_part2(char *input, char **split)
{
	(void)input;
	int len;
	t_coords *co;
	int i;

	len = 0;
	while(split[len])
		len++;
	co = malloc(len * sizeof(t_coords));
	i = 0;
	while(split[i])
	{
		co[i] = parse_line(split[i]);	
		i++;
	}
	return(get_biggest_area(co, len));
}
// 4604141472 >
// 4604141472 :/ 
// 4501110590 >
// 1588990708