/*
 * Copyright (C) 2017 Red Hat, Inc.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * Author: Gris Ge <fge@redhat.com>
 */

#include <stdint.h>
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#include <dirent.h>
#include <string.h>
#include <unistd.h>

#include "libopeniscsiusr/libopeniscsiusr.h"
#include "misc.h"
#include "context.h"

#define _UNUSED(x) (void)(x)

#define _ISCSI_LOG_STRERR_ALIGN_WIDTH	80
/* ^ Only used in _iscsi_log_stderr() for pretty log output.
 *   When provided log message is less than 80 bytes, fill it with space, then
 *   print code file name, function name, line after the 80th bytes.
 */

struct _num_str_conv {
	const uint32_t value;
	const char *str;
};

#define _iscsi_str_func_gen(func_name, var_type, var, conv_array) \
const char *func_name(var_type var) { \
	size_t i = 0; \
	uint32_t tmp_var = var & UINT32_MAX; \
	errno = 0; \
	/* In the whole libopeniscsiusr, we don't have negative value */ \
	for (; i < sizeof(conv_array)/sizeof(conv_array[0]); ++i) { \
		if ((conv_array[i].value) == tmp_var) \
			return conv_array[i].str; \
	} \
	errno = EINVAL; \
	return "Invalid argument"; \
}

static const struct _num_str_conv _ISCSI_RC_MSG_CONV[] = {
	{LIBISCSI_OK, "OK"},
	{LIBISCSI_ERR_BUG, "BUG of libopeniscsiusr library"},
	{LIBISCSI_ERR_SESS_NOT_FOUND, "Specified iSCSI session not found"},
	{LIBISCSI_ERR_ACCESS, "Permission deny"},
	{LIBISCSI_ERR_NOMEM, "Out of memory"},
	{LIBISCSI_ERR_SYSFS_LOOKUP, "Could not lookup object in sysfs"},
};

_iscsi_str_func_gen(iscsi_strerror, int, rc, _ISCSI_RC_MSG_CONV);

static const struct _num_str_conv _ISCSI_PRI_CONV[] = {
	{LIBISCSI_LOG_PRIORITY_DEBUG, "DEBUG"},
	{LIBISCSI_LOG_PRIORITY_INFO, "INFO"},
	{LIBISCSI_LOG_PRIORITY_WARNING, "WARNING"},
	{LIBISCSI_LOG_PRIORITY_ERROR, "ERROR"},
};

_iscsi_str_func_gen(iscsi_log_priority_str, int, priority, _ISCSI_PRI_CONV);

void _iscsi_log_stderr(struct iscsi_context *ctx, int priority,
		       const char *file, int line, const char *func_name,
		       const char *format, va_list args)
{
	int printed_bytes = 0;

	_UNUSED(ctx);

	printed_bytes += fprintf(stderr, "iSCSI %s: ",
				 iscsi_log_priority_str(priority));
	printed_bytes += vfprintf(stderr, format, args);

	if (printed_bytes < _ISCSI_LOG_STRERR_ALIGN_WIDTH) {
		fprintf(stderr, "%*s # %s:%s():%d\n",
			_ISCSI_LOG_STRERR_ALIGN_WIDTH - printed_bytes, "", file,
			func_name, line);
	} else {
		fprintf(stderr, " # %s:%s():%d\n", file, func_name, line);
	}
}

void _iscsi_log(struct iscsi_context *ctx, int priority, const char *file,
		int line, const char *func_name, const char *format, ...)
{
	va_list args;

	if (ctx->log_func == NULL)
		return;

	va_start(args, format);
	ctx->log_func(ctx, priority, file, line, func_name, format, args);
	va_end(args);
}

int _scan_filter_skip_dot(const struct dirent *dir)
{
	return strcmp(dir->d_name, ".") && strcmp(dir->d_name, "..");
}

bool _file_exists(const char *path)
{
	if (access(path, F_OK) == 0)
		return true;
	else
		return false;
}