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// Copyright 2025 Shota FUJI
//
// Licensed under the Zero-Clause BSD License or the Apache License, Version 2.0, at your option.
// You may not use, copy, modify, or distribute this file except according to those terms. You can
// find a copy of the Zero-Clause BSD License at LICENSES/0BSD.txt, and a copy of the Apache License,
// Version 2.0 at LICENSES/Apache-2.0.txt. You may also obtain a copy of the Apache License, Version
// 2.0 at <https://www.apache.org/licenses/LICENSE-2.0>
//
// SPDX-License-Identifier: 0BSD OR Apache-2.0

#include <errno.h>
#include <netinet/in.h>
#include <stdio.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/time.h>
#include <unistd.h>

#include <sood.h>

int main(int argc, char **argv) {
	struct sockaddr_in multicast_addr;
	multicast_addr.sin_family = AF_INET;
	// Port is network byte order both in Linux and macOS
	multicast_addr.sin_port = htons(sood_discovery_server_udp_port);
	#ifdef __linux__
	// Linux uses network byte order for IP addr part. Great consistency.
	multicast_addr.sin_addr.s_addr = sood_discovery_multicast_ipv4_address_be;
	#else
	// Windows and macOS seem to use host byte order. fuck.
	multicast_addr.sin_addr.s_addr = ntohl(sood_discovery_multicast_ipv4_address_be);
	#endif

	int sockfd = socket(AF_INET, SOCK_DGRAM, 0);
	if (sockfd < 0) {
		printf("Failed to create socket: %d\n", errno);
		return 1;
	}

	if (setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &(int){1}, sizeof(int)) < 0) {
		printf("Failed to set SO_REUSEADDR=1: %d\n", errno);
		close(sockfd);
		return 1;
	}

	struct timeval timeout;
	timeout.tv_sec = 5;
	timeout.tv_usec = 0;

	if (setsockopt(sockfd, SOL_SOCKET, SO_RCVTIMEO, &timeout, sizeof(timeout)) < 0) {
		printf("Failed to set SO_RCVTIMEO: %d\n", errno);
		close(sockfd);
		return 1;
	}

	while (1) {
		if (
			sendto(
				sockfd,
				sood_discovery_query_prebuilt,
				sizeof(sood_discovery_query_prebuilt),
				0,
				(struct sockaddr*)&multicast_addr,
				sizeof(multicast_addr)
			) < 0
		) {
			printf("Failed to send: %d\n", errno);
			close(sockfd);
			return 1;
		}

		char received[512];
		ssize_t received_size = recv(sockfd, received, sizeof(received), 0);
		if (received_size < 0) {
			if (errno == EAGAIN || errno == EWOULDBLOCK) {
				printf("Retrying...\n");
				continue;
			}

			printf("Failed to recv: %d\n", errno);
			close(sockfd);
			return 1;
		}

		sood_discovery_response resp;
		sood_discovery_response_parse_result result = sood_discovery_response_parse(
			&resp,
			received,
			received_size
		);
		if (result != SOOD_DISCOVERY_RESPONSE_PARSE_OK) {
			printf("Parse error: %d\n", result);
			close(sockfd);
			return 2;
		}

		printf("Name: \t\t%.*s\n", resp.name_len, resp.name_ptr);
		printf("Version: \t%.*s\n", resp.display_version_len, resp.display_version_ptr);
		printf("Unique ID: \t%.*s\n", resp.unique_id_len, resp.unique_id_ptr);
		printf("HTTP port: \t%d\n", resp.http_port);
		return 0;
	}
}