/*
 * Copyright (c) 2023 Valtteri Koskivuori <vkoskiv@gmail.com>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#ifndef _MACNTP_H
#define _MACNTP_H

enum MacNTPError {
	Success = 0,
	MacTCPInitFailed,
	InvalidURL,
	BadNtpStructSize,
	UDPCreateFailed,
	UDPSendFailed,
	UDPRcvFailed,
	InvalidNTPResponse,
	OriginTimestampMismatch,
	DNSResolveFailed,
	// Below only for SetSystemTime
	ClockWriteFailed,
	ClockReadFailed,
	UDPRcvTimedOut,
	PacketParamNull
};

struct ntp_ts {
	unsigned long upper; /* Seconds since 1904-01-01 */
	unsigned long lower; /* FIXME: These values seem to be wrong */
};

struct ntp_packet {
	unsigned char li_vn_mode;
	unsigned char stratum;
	unsigned char poll;
	char precision;
	
	unsigned long root_delay;
	unsigned long root_dispersion;
	unsigned long reference_id;
	
	struct ntp_ts reference_timestamp;
	struct ntp_ts origin_timestamp;
	struct ntp_ts receive_timestamp;
	struct ntp_ts transmit_timestamp;
};

typedef long minutes_t;

enum MacNTPError MacNTPFetchTime(char *ntp_url, struct ntp_packet *packet, OSErr *supplemental, minutes_t utc_offset);

// For convenience, you can just pass ntp_packet from above to set the system time
// Optionally, you can care about the contents of ntp_packet and do things with it.
enum MacNTPError MacNTPSetSystemTime(struct ntp_packet *ntp, minutes_t utc_offset);

#endif