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/* ************************************************************************** */
/*                                                                            */
/*                                                        :::      ::::::::   */
/*   sorting.c                                          :+:      :+:    :+:   */
/*                                                    +:+ +:+         +:+     */
/*   By: dkaiser <dkaiser@student.42heilbronn.de    +#+  +:+       +#+        */
/*                                                +#+#+#+#+#+   +#+           */
/*   Created: 2024/04/13 15:04:19 by dkaiser           #+#    #+#             */
/*   Updated: 2024/04/24 10:58:02 by dkaiser          ###   ########.fr       */
/*                                                                            */
/* ************************************************************************** */

#include "libft/ft_printf.h"
#include "push_swap.h"

static void	presort(t_psdata *data)
{
	int	size;
	int	pivot;
	int	max;

	size = data->a->size;
	pivot = size / 2;
	max = data->a->stack[0];
	while (size--)
	{
		if (data->a->stack[0] < max)
		{
			run_command(data, PB);
			if (data->b->stack[0] < pivot)
				run_command(data, RB);
		}
		else
		{
			max = data->a->stack[0];
			run_command(data, RA);
		}
	}
}

static int	calculate_score(t_psdata *data, int pos)
{
	int	moves_to_top;
	int	moves_to_spot;
	int	i;

	if (pos < (data->b->size + 1) / 2)
		moves_to_top = pos;
	else
		moves_to_top = data->b->size - pos;
	i = 0;
	while (i < data->a->size && data->a->stack[i] > data->b->stack[pos])
		i++;
	if (i < (data->a->size + 1) / 2)
		moves_to_spot = 2 * i + 1;
	else
		moves_to_spot = 2 * ((data->a->size - i) + 1);
	return (moves_to_top + moves_to_spot);
}

static void	move_to_top(t_psdata *data, int idx)
{
	if (idx < (data->b->size + 1) / 2)
	{
		while (--idx > 0)
			run_command(data, RB);
	}
	else
	{
		idx = data->b->size - idx;
		while (idx--)
			run_command(data, RRB);
	}
}

static void	move_to_spot(t_psdata *data, int idx)
{
	int	pos;
	int	i;

	pos = 0;
	while (pos < data->a->size && data->b->stack[0] > data->a->stack[pos])
		pos++;
	if (pos >= data->a->size)
	{
		move_to_top(data, idx);
		run_command(data, PA);
		run_command(data, RA);
	}
	else if (pos < (data->a->size + 1) / 2)
	{
		i = pos;
		while (i--)
			run_command(data, RA);
		move_to_top(data, idx);
		run_command(data, PA);
		i = pos;
		while (i--)
			run_command(data, RRA);
	}
	else
	{
		i = data->a->size - pos;
		while (i--)
			run_command(data, RRA);
		move_to_top(data, idx);
		run_command(data, PA);
		i = data->a->size - pos;
		while (i--)
			run_command(data, RA);
	}
}

static void	scoresort(t_psdata *data)
{
	int	*scores;
	int	i;
	int	min_score;

	scores = malloc(sizeof(int) * data->b->size);
	// Error if allocation fails
	i = 0;
	while (i < data->b->size)
	{
		scores[i] = calculate_score(data, i);
		i++;
	}
	i = 0;
	min_score = 0;
	while (i < data->b->size)
	{
		if (scores[i] < scores[min_score])
			min_score = i;
		i++;
	}
	move_to_spot(data, min_score);
	free(scores);
	if (data->b->size > 0)
		scoresort(data);
}

void	stack_sort(t_psdata *data)
{
	presort(data);
	scoresort(data);
}