/* librairie standard ... */
#include <stdlib.h>
/* pour getopt */
#include <unistd.h>
/* déclaration des types de base */
#include <sys/types.h>
/* constantes relatives aux domaines, types et protocoles */
#include <sys/socket.h>
/* constantes et structures propres au domaine UNIX */
#include <sys/un.h>
/* constantes et structures propres au domaine INTERNET */
#include <netinet/in.h>
/* structures retournées par les fonctions de gestion de la base de
données du réseau */
#include <netdb.h>
/* pour les entrées/sorties */
#include <stdio.h>
/* pour la gestion des erreurs */
#include <errno.h>

#define DEFAULTPORT 9000
#define MSG_LENGTH 10

void usage(char* prog) {
	printf("usage: %s [-p|-s][-u][-n ##]\n", prog);
}

void construire_message(char* message, char motif, int lg) {
	for (int i = 0; i < lg; ++i) {
		message[i] = motif;
	}
	message[lg] = '\0';
}

void recvudp(int sock, char* buffer, int buf_len, void* addr, unsigned int addr_len) {
	int lg_recv = recvfrom(sock, buffer, buf_len, 0, (struct sockaddr*) addr, &addr_len);
	if (lg_recv == -1) {
		perror("Message could not be recieved, Error: ");
		exit(1);
	} else if (lg_recv < buf_len) {
		fprintf(stderr, "Only %i from %i characters have been reviewed.", lg_recv, buf_len);
		exit(1);
	}
}

void afficher_message(char* message, int lg) {
	message[lg] = '\0';
	printf("message construit: %s", message);
}

int main (int argc, char **argv)
{
	int c;
	extern char *optarg;
	extern int optind;
	int nb_message = -1; /* Nb de messages à envoyer ou à recevoir, par défaut : 10 en émission, infini en réception */
	int source = -1 ; /* 0=puits, 1=source */
	char* hostname;
	int protocole = 0; /* 0=tcp, 1=udp */
	int sock;
	char* message;
	struct hostent *hp;
	struct sockaddr_in addr;
	while ((c = getopt(argc, argv, "hu:pn:s")) != -1) {
		switch (c) {
			case 'h':
				usage(argv[0]);
				return 0;
			case 'p':
				if (source == 1) {
					usage(argv[0]);
					/* printf("usage: cmd [-p|-s][-n ##]\n"); */
					exit(1);
				}
				source = 0;
				break;

			case 's':
				if (source == 0) {
					usage(argv[0]);
					/* printf("usage: cmd [-p|-s][-n ##]\n"); */
					exit(1) ;
				}
				source = 1;
				break;

			case 'n':
				nb_message = atoi(optarg);
				break;

			case 'u':
				protocole = 1;
				printf("%s\n", optarg);
				hostname = optarg;
				/* hostname = malloc((strlen(optarg) + 1) * sizeof(char)); */
				/* strcpy(hostname, optarg); */
				break;

			default:
				usage(argv[0]);
				/* printf("usage: cmd [-p|-s][-n ##]\n"); */
				break;
		}
	}

	if (source == -1) {
		usage(argv[0]);
		/* printf("usage: cmd [-p|-s][-n ##]\n"); */
		exit(1) ;
	}

	if (source == 1)
		printf("on est dans le source\n");
	else
		printf("on est dans le puits\n");

	if (nb_message != -1) {
		if (source == 1)
			printf("nb de tampons à envoyer : %d\n", nb_message);
		else
			printf("nb de tampons à recevoir : %d\n", nb_message);
	} else {
		if (source == 1) {
			nb_message = 10 ;
			printf("nb de tampons à envoyer = 10 par défaut\n");
		} else {
			// changed envoyer to recevoir
			printf("nb de tampons à recevoir = infini\n");
		}

	}
	/* protocole = 0 (udp) 1(tcp) */
	if (!protocole) /* if (tcp activated) */ {
		printf("TCP not implemented\n");
		return 0;
	} else {
		printf("using udp\n");
	}
	/* if (protocole) /\* udp *\/ { */
	sock = socket(AF_INET, SOCK_DGRAM, 0);
	/* } else { */
	/* 	sock = socket(AF_INET, SOCK_STREAM, 0); */
	/* } */
	if (sock < 0) {
		perror("Error creating socket:");
		exit(1);
	}

	printf("socket created\n");

	memset(&addr, 0, sizeof(addr));
	addr.sin_family = AF_INET;
	addr.sin_port = DEFAULTPORT;
	printf("%s\n", hostname);
	hp = gethostbyname(hostname);
	if (hp == NULL) {
		printf("hosname not found\n");
		/* herror("Error: "); */
		exit(1);
	}
	printf("hostname found\n");

	memcpy(&addr.sin_addr.s_addr, hp->h_addr, hp->h_length);

	printf("address built\n");
	if (bind(sock, (struct sockaddr*) &addr, (sizeof(addr))) < 0 ) {
		perror("Error while binding socket: ");
		exit(1);
	}

	printf("socket bound\n");

	message = malloc((MSG_LENGTH + 1) * sizeof(char));
	if (source) {
		construire_message(message, 'a', MSG_LENGTH);
		for (int i = 0; i < nb_message; ++i) {
			int lg_sent = sendto(sock, message, MSG_LENGTH, 0, (struct sockaddr*) &addr, sizeof(addr));
			if (lg_sent == -1) {
				perror("Message could not be sent, Error: ");
				exit(1);
			} else if (lg_sent < MSG_LENGTH) {
				fprintf(stderr, "Only %i from %i characters have been sent.", lg_sent, MSG_LENGTH);
				exit(1);
			}
			printf("message sent: %s\n", message);
		}
	} else {
		printf("puit not implemented\n");
	}


	if (close(sock) < 0) {
		perror("Error closing socket:");
		exit(1);
	}
	return 0;
}