/* ************************************************************************** */
/*                                                                            */
/*                                                        :::      ::::::::   */
/*   bfs.c                                              :+:      :+:    :+:   */
/*                                                    +:+ +:+         +:+     */
/*   By: tmaze <tmaze@student.42.fr>                +#+  +:+       +#+        */
/*                                                +#+#+#+#+#+   +#+           */
/*   Created: 2019/03/27 14:41:49 by tmaze             #+#    #+#             */
/*   Updated: 2019/04/05 13:24:22 by tmaze            ###   ########.fr       */
/*                                                                            */
/* ************************************************************************** */

#include "lem_in.h"

static void	bfs_addtoqueue(t_bfs *tab, int node, int nb_nodes)
{
	int	i;

	i = 0;
	if (tab[node].visited == 0)
	{
		while (i < nb_nodes && tab[i].queue != -1 && tab[i].queue != node)
			i++;
		if (i < nb_nodes && tab[i].queue == -1)
			tab[i].queue = node;
	}
}

static void	bfs_checkadj(t_lmdata *data, t_bfs *tab, int i)
{
	t_ind	*it;
	char	used;

	it = data->adj[tab[i].queue];
	used = 0;
	while (it != NULL)
	{
		if (tab[it->index].visited == 0 && it->weight == 2)
			used = 1;
		if (tab[it->index].visited == 0 && it->weight == 2)
			break ;
		it = it->next;
	}
	it = data->adj[tab[i].queue];
	while (it != NULL)
	{
		if (tab[it->index].visited == 0 && ((!used && it->weight > 0)
											|| (used && it->weight == 2)))
			bfs_addtoqueue(tab, it->index, data->nb_nodes);
		if (tab[it->index].visited == 0 && ((!used && it->weight > 0)
											|| (used && it->weight == 2)))
			tab[it->index].parent = tab[i].queue;
		it = it->next;
	}
}

static void	bfs_init(t_bfs *tab, t_lmdata *data)
{
	int	i;

	i = 0;
	while (i < data->nb_nodes)
	{
		tab[i].parent = -1;
		tab[i].visited = 0;
		tab[i].queue = -1;
		i++;
	}
}

void		bfs(t_lmdata *data, t_bfs *tab, int start_ind, int end_ind)
{
	int		i;

	bfs_init(tab, data);
	bfs_addtoqueue(tab, start_ind, data->nb_nodes);
	i = 0;
	while (i < data->nb_nodes && tab[i].queue != -1
			&& tab[end_ind].parent == -1 && (tab[tab[i].queue].visited = 1))
		bfs_checkadj(data, tab, i++);
}