/*

 * Copyright (C) 2013 Intel Corporation

 *

 * Licensed under the Apache License, Version 2.0 (the "License");

 * you may not use this file except in compliance with the License.

 * You may obtain a copy of the License at

 *

 *      http://www.apache.org/licenses/LICENSE-2.0

 *

 * Unless required by applicable law or agreed to in writing, software

 * distributed under the License is distributed on an "AS IS" BASIS,

 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

 * See the License for the specific language governing permissions and

 * limitations under the License.

 *

 */

#include <stdlib.h>

#include <string.h>

#include <stdio.h>

#include <ctype.h>

#include "history.h"

/* Very simple history storage for easy usage of tool */

#define HISTORY_DEPTH 40

#define LINE_SIZE 200

static char lines[HISTORY_DEPTH][LINE_SIZE];

static int last_line = 0;

static int history_size = 0;

/* TODO: Storing history not implemented yet */

void history_store(const char *filename)

{

}

/* Restoring history from file */

void history_restore(const char *filename)

{

	char line[1000];

	FILE *f = fopen(filename, "rt");

	if (f == NULL)

		return;

	for (;;) {

		if (fgets(line, 1000, f) != NULL) {

			int l = strlen(line);

			while (l > 0 && isspace(line[--l]))

				line[l] = 0;

			if (l > 0)

				history_add_line(line);

		} else

			break;

	}

	fclose(f);

}

/* Add new line to history buffer */

void history_add_line(const char *line)

{

	if (line == NULL || strlen(line) == 0)

		return;

	if (strcmp(line, lines[last_line]) == 0)

		return;

	last_line = (last_line + 1) % HISTORY_DEPTH;

	strncpy(&lines[last_line][0], line, LINE_SIZE - 1);

	if (history_size < HISTORY_DEPTH)

		history_size++;

}

/*

 * Get n-th line from history

 * 0 - means latest

 * -1 - means oldest

 * return -1 if there is no such line

 */

int history_get_line(int n, char *buf, int buf_size)

{

	if (n == -1)

		n = history_size - 1;

	if (n >= history_size || buf_size == 0 || n < 0)

		return -1;

	strncpy(buf,

		&lines[(HISTORY_DEPTH + last_line - n) % HISTORY_DEPTH][0],

		buf_size - 1);

	buf[buf_size - 1] = 0;

	return n;

}