// Run like this:  simple_client address port
// Results in argv ["./simple_client", "address", "port"]

#include<sys/socket.h>
#include<sys/types.h>
#include<netinet/ip.h>
#include<netdb.h>
#include<arpa/inet.h>
#include<stdio.h>
#include<unistd.h>
#include<stdlib.h>

int main(int argc, char ** argv){
	if(argc < 3){
		printf("Usage:  %s hostname port\n", argv[0]);
		return 1;
	}
	struct sockaddr_in sad;
	sad.sin_port = htons(atoi(argv[2]));
	sad.sin_family = AF_INET;

	int skt = socket(AF_INET, SOCK_STREAM, 0);

	// do a dns lookup
	struct hostent* entry = gethostbyname(argv[1]);
	if(!entry){
		if(h_errno == HOST_NOT_FOUND){
			printf("This is our own message that says the host wasn't found\n");
		}
		herror("gethostbyname");
		return 1;
	}
	struct in_addr **addr_list = (struct in_addr**)entry->h_addr_list;
	struct in_addr* c_addr = addr_list[0];
	char* ip_string = inet_ntoa(*c_addr);
	sad.sin_addr = *c_addr; // copy the address we found into sad
	// Finally done with DNS!
	printf("Connecting to:  %s\n", ip_string);

	if( connect(skt, (struct sockaddr*)&sad, sizeof(struct sockaddr_in)) ){
		perror("connect");
		return 1;
	}
	char message[128];
	uint16_t messagelen;
	if(2 != read(skt, &messagelen, 2)){
		printf("We have some kind of problem\n");
		return 1;
	}
	uint16_t expected_total = messagelen + sizeof(int) + sizeof(double);
	/* This way works, but there is an easier way
	ssize_t actual_length = read(skt, message, 128);
	while(actual_length < expected_total)
		actual_length += read(skt, message + actual_length, 128 - actual_length);
	*/
	/* This works, but what a mess! 
	ssize_t actual_length = recv(skt, message, expected_total, MSG_WAITALL);
	printf("Received message(%ld bytes):  %s\n", actual_length, message);
	printf("moosenum = %d\n", *(int*)(message + messagelen));
	printf("mooseweight = %lf\n", *(double*)(message + messagelen + sizeof(int)));
	*/
	// One way:  Meter everything on the way out
	if(127 > messagelen) {
		recv(skt, message, messagelen, MSG_WAITALL);
		message[messagelen] = 0;
		printf("The message:  %s\n", message);
	} else {
		printf("Oh no, we don't have enough space to read the message!\n");
	}
	/*
	int32_t moosenum;
	recv(skt, &moosenum, 4, MSG_WAITALL);
	printf("moosenum = %d\n", moosenum);

	double mooseweight;
	recv(skt, &mooseweight, 8, MSG_WAITALL);
	printf("mooseweight = %lf\n", mooseweight);
	*/
	// One more way, to reduce recv calls
	struct moosedata {
		int32_t moosenum;
		double mooseweight;
	}__attribute__((packed));
	struct moosedata md;
	printf("sizeof(struct moosedata) = %lu\n", sizeof(struct moosedata));
	recv(skt, &md, sizeof(md), MSG_WAITALL);
	printf("moosenum = %d\n", md.moosenum);
	printf("mooseweight = %lf\n", md.mooseweight);
	close(skt);
	return 0;
}