/**
 * thunar_file_is_in_dot_hidden_file:
 * @file : a #ThunarFile instance.
 *
 * Checks whether @file name is contained in a .hidden
 * file in the same directory as @file.
 *
 * Return value: %TRUE if .hidden contains @file name, else %FALSE.
 **/

gboolean thunar_file_is_in_dot_hidden_file (const ThunarFile *file)
{
	/* name of the last folder used when calling this function */
	static gchar *last_parent = NULL;
	/* searchable contents of .hidden file */
	static GHashTable *hidden_hash = NULL;

	/* basename of file */
	gchar *basename = thunar_vfs_path_get_name (THUNAR_FILE ((file))->info->path);

	/* name of folder containing the file */
	gchar *parent = NULL;

	/* get parent of file */
	if (thunar_file_has_parent (THUNAR_FILE ((file))))
	{
		parent = thunar_vfs_path_dup_string (thunar_vfs_path_get_parent (THUNAR_FILE ((file))->info->path));
	}
	else 
	{
		ThunarVfsPath *parent_path = thunar_vfs_path_get_for_root ();
		parent = thunar_vfs_path_dup_string (parent_path);
		thunar_vfs_path_unref (parent_path);
	}

	/* reread .hidden file when changing to new directory */
	/* TODO: should also reread if .hidden file changes */
	if ( g_strcmp0 (last_parent, parent) != 0 )
	{
		gchar *hidden_file = g_build_filename (parent, ".hidden", NULL);

		g_hash_table_destroy (hidden_hash);
		hidden_hash = NULL;
		g_free (last_parent);
		last_parent = g_strdup (parent);

		/* If there is a .hidden file in the parent folder, read contents 
		 * into hash file */
		if (g_file_test (hidden_file, G_FILE_TEST_IS_REGULAR))
		{
			FILE *read = fopen (hidden_file, "r");
			const int max_line_length = 255;
			g_char *line[max_line_length];

			hidden_hash = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, g_free);

			while (fgets (line, max_line_length, read))
			{
				g_char *insert;

				/* remove trailing newlines */
				int last = strlen (line)-1;
				if (line [last] == '\n')
				{
					line [last] = '\0';
				}
				/* memory allocated for insert will be freed when hidden_hash is destroyed */
				insert = g_strdup (line);

				g_hash_table_insert (hidden_hash, insert, insert);
			}
			fclose (read);
		}
		g_free (hidden_file);
	}

	g_free (parent);

	return ( hidden_hash != NULL) && ( g_hash_table_lookup (hidden_hash, basename ) );
}