/*
 * The Rin Library – diagnostics module
 *
 * Copyright (C) 2015 Gediminas Jakutis
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; version 2.1
 * of the License.
 *
 * 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
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
 */

#include "diagnostic_private.h"

#include <stdlib.h>
#include <string.h>
#include <time.h>
#include "rin/diagnostic.h"
#include "rin/time.h"
#include "rin/definitions.h"

static const char default_format[] = "C:F:mn";
static const char valid_format[] = "CFtTn:m";

static struct iostate {
	char pidconv[8];
	struct timespec start;
	FILE *err;
	FILE *warn;
	FILE *fixme;
	FILE *info;
	char *err_format;
	char *warn_format;
	char *fixme_format;
	char *info_format;
} state = {"%08x:", {0, 0}, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL};

void rin_diag_cleanup(void)
{
	char *tmp;

	tmp = state.err_format;
	state.err_format = NULL;
	free(tmp);

	tmp = state.warn_format;
	state.warn_format = NULL;
	free(tmp);

	tmp = state.fixme_format;
	state.fixme_format = NULL;
	free(tmp);

	tmp = state.info_format;
	state.info_format = NULL;
	free(tmp);
}

void rin_diag_init(void)
{
	static const char convstr[8] = "%04hx:";

	clock_gettime(RIN_CLOCK_WALL_COUNTER, &state.start);

	if (sizeof(pid_t) == 4) {
		memcpy(state.pidconv, convstr, sizeof(convstr));
	}

	atexit(rin_diag_cleanup);
}

int rin_diag_format(enum rin_diag_outstream channel, const char *format)
{
	char *tmp;
	size_t i, j;

	if (!format) {
		tmp = NULL;
	} else {
		for (i = 0; format[i]; ++i) {
			int valid = 0;

			for (j = 0; valid_format[j]; ++j) {
				if (valid_format[j] == format [i]) {
					valid = 1;
					break;
				}
			}

			if (!valid) {
				return EINVAL;
			}
		}

		tmp = strdup(format);
	}

	switch (channel) {
	case rin_diag_err:
		free(state.err_format);
		state.err_format = tmp;
		break;
	case rin_diag_warn:
		free(state.warn_format);
		state.warn_format = tmp;
		break;
	case rin_diag_fixme:
		free(state.fixme_format);
		state.fixme_format = tmp;
		break;
	case rin_diag_info:
		free(state.info_format);
		state.info_format = tmp;
		break;
	default:
		return EINVAL;
	}

	return 0;
}

int rin_diag_set_outstream(enum rin_diag_outstream channel, FILE *stream)
{
	switch (channel) {
	case rin_diag_err:
		state.err = stream;
		break;
	case rin_diag_warn:
		state.warn = stream;
		break;
	case rin_diag_fixme:
		state.fixme = stream;
		break;
	case rin_diag_info:
		state.info = stream;
		break;
	default:
		return EINVAL;
	}

	return 0;
}

void __rin_err(const char *func_name, const char *format, ...)
{
	va_list args;

	va_start(args, format);
	__rin_msg(state.err ? state.err : stderr, "error", func_name,
			state.err_format ? state.err_format : default_format,
			format, args);
}

void __rin_warn(const char *func_name, const char *format, ...)
{
	va_list args;

	va_start(args, format);
	__rin_msg(state.warn ? state.warn : stderr, "warning", func_name,
			state.warn_format ? state.warn_format : default_format,
			format, args);
}

void __rin_fixme(const char *func_name, const char *format, ...)
{
	va_list args;

	va_start(args, format);
	__rin_msg(state.fixme ? state.fixme : stderr, "fixme", func_name,
			state.fixme_format ? state.fixme_format : default_format,
			format, args);
}

void __rin_info(const char *func_name, const char *format, ...)
{
	va_list args;

	va_start(args, format);
	__rin_msg(state.info ? state.info : stdout, "info", func_name,
			state.info_format ? state.info_format : default_format,
			format, args);
}

static void __rin_msg(FILE *stream, const char *prefix, const char *func_name, const char *rin_format, const char *format, va_list args)
{
	struct timespec t;
	size_t i;
	int gottime = 0;

	for (i = 0; rin_format[i]; ++i) {
		switch (rin_format[i]) {
		case 'C':
			fprintf(stream, "%s", prefix);
			break;
		case 'F':
			fprintf(stream, "%s", func_name);
			break;
		case 't':
			fprintf(stream, state.pidconv, gettid());
			break;
		case 'T':
			if (!gottime) {
				clock_gettime(RIN_CLOCK_WALL_COUNTER, &t);
				t = rin_time_sub(&t, &state.start);
				gottime = 1;
			}

			fprintf(stream, "%lus%06lu.%03luµs", t.tv_sec, t.tv_nsec / 1000, t.tv_nsec % 1000);
			break;
		case 'n':
			fprintf(stream, "\n");
			break;
		case ':':
			fprintf(stream, ":");
			break;
		case 'm':
			vfprintf(stream, format, args);
			break;
		}
	}
}