// 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 for a query:  %s hostname port\n", argv[0]);
		printf("Usage for a report:  %s hostname port number\n", argv[0]);
		return 1;
	}
	uint32_t squirrels = 0;
	if(argc == 4){ // We must be sending a report
		squirrels = atoi(argv[3]);
		if(squirrels == 0) {
			printf("Can't report 0 squirrels\n");
			return 1;
		}
	}
	struct sockaddr_in sad;
	sad.sin_port = htons(atoi(argv[2]));
	sad.sin_family = AF_INET;
	printf("port:  %d\n", sad.sin_port);

	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;  // -> is like (*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;
	}

	if(squirrels){ // We're sending a report
		uint8_t type = 1;
		printf("Reporting %d squirrels\n", squirrels);
		write(skt, &type, 1);
		write(skt, &squirrels, 4);
		read(skt, &type, 1);
		if(type == 3)
			printf("Report was received!\n");
		else
			printf("Report was not received - did we connect to the right server?\n");

	} else { // We're sending a query
		uint8_t type = 2;
		write(skt, &type, 1);
		read(skt, &type, 1);
		if(type == 4){
			read(skt, &squirrels, 4);
			printf("Total is %d squirrels\n", squirrels);
		} else {
			printf("Unexpected response %d from server\n", type);
		}
	}

	close(skt);
	return 0;
}