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

static struct iostate {
	FILE *err;
	FILE *warn;
	FILE *fixme;
	FILE *info;
	unsigned int flags;
	char pidconv[8];
} state = {NULL, NULL, NULL, NULL, RIN_DIAG_PREFIX, "%08x:"};

int rin_diag_flags(int flag, int action)
{
	/* checking for non-existent flags */
	if (flag & ~(RIN_DIAG_ALLFLAGS)) {
		return EINVAL;
	}

	state.flags = action ? (state.flags | flag) : (state.flags & ~(flag));

	return 0;
}

int rin_diag_set_outstream(enum rin_diag_outstream channel, FILE *stream)
{
	if (!stream) {
		return EINVAL;
	}

	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 *format, ...)
{
	va_list args;

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

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

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

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

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

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

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

static void __rin_msg(FILE *stream, const char *prefix, const char *format, va_list args)
{
	rin_once(__rin_pidconvadjust());

	if (state.flags & RIN_DIAG_PREFIX) {
		fprintf(stream, "%s:", prefix);
	}

	if (state.flags & RIN_DIAG_THREADNUM) {
		fprintf(stream, state.pidconv, gettid());
	}

	if (state.flags & RIN_DIAG_TIME) {
		struct timespec t;
		clock_gettime(CLOCK_REALTIME, &t);
		fprintf(stream, "%lu.%lu:", t.tv_sec, t.tv_nsec);
	}

	vfprintf(stream, format, args);
}

static void __rin_pidconvadjust(void)
{
	if (sizeof(pid_t) == 4) {
		const char convstr[8] = "%04hx:";
		memcpy(state.pidconv, convstr, sizeof(convstr));
	}
}