#include <netdb.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <unistd.h>

#include "config.h"

/* 4 extra bytes for the two escape characters (), the action character, and
 * the carriage return (\r) */
static const size_t BUF_SIZE = sizeof(PASSWORD) + 4;

int create_socket()
{
	int sockfd;
	struct addrinfo *result, *rp;
	struct addrinfo hints = {
		.ai_family = AF_INET,
		.ai_socktype = SOCK_STREAM,
		.ai_flags = 0,
		.ai_protocol = 0,
	};

	int s = getaddrinfo(ADDRESS, PORT, &hints, &result);
	if (s != 0) {
		fprintf(stderr, "getaddrinfo: %s\n", gai_strerror(s));
		exit(EXIT_FAILURE);
	}

	for (rp = result; rp != NULL; rp = rp->ai_next) {
		sockfd = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
		if (sockfd == -1) {
			continue;
		}

		if (connect(sockfd, rp->ai_addr, rp->ai_addrlen) != -1) {
			break;
		}

		close(sockfd);
	}

	if (rp == NULL) {
		fprintf(stderr, "Could not connect\n");
		exit(EXIT_FAILURE);
	}

	freeaddrinfo(result);

	return sockfd;
}

void send_command(int sockfd, char action)
{
	char buf[BUF_SIZE];
	sprintf(buf, "%s%c\r", PASSWORD, action);
	if (write(sockfd, buf, BUF_SIZE) != BUF_SIZE) {
		fprintf(stderr, "partial/failed write\n");
		exit(EXIT_FAILURE);
	}

	memset(buf, 0, BUF_SIZE);
	ssize_t nread = read(sockfd, buf, BUF_SIZE);
	if (nread == -1) {
		perror("read");
		exit(EXIT_FAILURE);
	}

	printf("%s\n", buf);
}

int is_valid_action(char action)
{
	switch (action) {
	case 'n': /* ON */
	case 'f': /* OFF */
	case 'c': /* CYCLE */
	case 'q': /* QUERY */
		return 1;
	default:
		return 0;
	}
}

int main(int argc, char *argv[])
{
	if (argc < 2) {
		fprintf(stderr, "Usage: %s <n|f|c|q>\n", argv[0]);
		exit(EXIT_FAILURE);
	}

	char action = argv[1][0];
	if (!is_valid_action(action)) {
		fprintf(stderr, "Invalid action: %c\n", action);
		exit(EXIT_FAILURE);
	}

	int sockfd = create_socket();
	send_command(sockfd, action);

	exit(EXIT_SUCCESS);
}