#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>
#include<string>

/*
 * This is a very read-heavy way to go
 * It does work
 */
void examine_server_v1(int fd){
	char type; // or uint8_t
	ssize_t readlen;
	while(1){
		if((readlen = read(fd, &type, 1)) != 1)
			goto err;	
		if(type == 11){
			uint16_t initial_points, stat_limit, description_length;
			if(recv(fd, &initial_points, 2, MSG_WAITALL) != 2)
				goto err;
			if(recv(fd, &stat_limit, 2, MSG_WAITALL) != 2)
				goto err;
			if(recv(fd, &description_length, 2, MSG_WAITALL) != 2)
				goto err;
			char description[description_length + 1];
			if(recv(fd, &description, description_length, MSG_WAITALL) != description_length)
				goto err;
			description[description_length] = 0;
			printf("Game received.  \nInitial points:  %d\nStat limit:  %d\nDescription: %s\n", initial_points, stat_limit, description);
			printf("Disconnecting, since we finished\n");
			return; // What if we wanted to return our game description?
		} else if(type == 14){
			uint8_t major_version, minor_version;
			uint16_t extension_length;
			if(read(fd, &major_version, 1) != 1)
				goto err;
			if(read(fd, &minor_version, 1) != 1)
				goto err;
			if(recv(fd, &extension_length, 2, MSG_WAITALL) != 2)
				goto err;
			if(extension_length){
				char extensions[extension_length];
				if(recv(fd, extensions, extension_length, MSG_WAITALL) != extension_length)
					goto err;		
			}
			printf("Connected to lurk server with version %d.%d and %d bytes of extensions\n", major_version, minor_version, extension_length);
		} else {
			printf("Received type %d, probably not a lurk server\n", type);
			return;
		}
	}
err:
	printf("Error encountered, giving up\n");
}

struct game {
	uint16_t initial_points, stat_limit, description_length;
	std::string description;
	bool read(int fd){
		if(recv(fd, this, 6, MSG_WAITALL) != 6)
			return false;
		char tmp_description[description_length + 1];
		tmp_description[description_length] = 0;
		if(recv(fd, tmp_description, description_length, MSG_WAITALL) != description_length)
			return false;
		description = tmp_description; // Will probably cause a heap allocation
		return true;
	}
} __attribute__((packed));

struct version{
	uint8_t major_version, minor_version;
	uint16_t extension_length;

	void send(int fd){
		// code that sends ourselves to fd
		// Send type, next send ourselves with the "this" pointer:
		// write(fd, this, 4);
	}
	bool read(int fd){
		return recv(fd, this, sizeof(struct version), MSG_WAITALL) == 4;
	}
} __attribute__((packed));

struct game get_game_struct(int fd){
	char type; // or uint8_t
	struct game g = {0, 0, 0, ""};
	ssize_t readlen;
	while(1){
		if((readlen = read(fd, &type, 1)) != 1)
			goto err;	
		if(type == 14){
			struct version v;
			if(!v.read(fd))
				goto err;
			printf("Connected to lurk server with version %d.%d and %d bytes of extensions\n", v.major_version, v.minor_version, v.extension_length);
		} else if (type == 11){
			g.read(fd);
			printf("Game received.  \nInitial points:  %d\nStat limit:  %d\nDescription: %s\n", g.initial_points, g.stat_limit, g.description.c_str());
			return g;
		} else {
			printf("Received type %d, probably not a lurk server\n", type);
			return g;
		}
	}
err:
	printf("Error encountered, giving up\n");
	return g;
}


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;
	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;
	}
	struct game g = get_game_struct(skt);

	close(skt);
	return 0;
}