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

uint16_t current_port;

char *connect_error = RED("Terminated connect due to alarm on port %d\n");
char error_buffer[1024];
char *current_error;

void handle_alarm(int signum){
	printf(current_error, current_port);
}

char general_buffer[1024*64 + 1];
int check_for_server(char* hostname, uint16_t cport, char quiet){
	current_error = connect_error;
	current_port = cport;
	struct sockaddr_in sad;
	sad.sin_port = htons(cport);
	sad.sin_family = AF_INET;

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

	struct hostent* entry = gethostbyname(hostname);
	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;

	alarm(1);
	if(connect(skt, (struct sockaddr*)&sad, sizeof(struct sockaddr_in)))
		return 1;
	alarm(0);

	char type;
	char major = 2;
	char minor = 0;
	printf(PURPLE("Starting interaction with server on %u\n"), cport);
	ssize_t readlen = recv(skt, &type, 1, MSG_DONTWAIT); // Might hang right here with HTTP server
	if(readlen != 1){ // Maybe the server needs a moment
		sleep(1);
		if(1 != recv(skt, &type, 1, MSG_DONTWAIT))
			goto not_lurk_server;
	}
	current_error = error_buffer;
	if(type == 14){ // we might have a version
		sprintf(error_buffer, RED("Terminated while waiting after receiving type 14 on port %d\n"), current_port);	
		alarm(1);
		if(read(skt, &major, 1) != 1)
			goto not_lurk_server;
		if(read(skt, &minor, 1) != 1)
			goto not_lurk_server;
		uint16_t extlen;
		if(read(skt, &extlen, 2) != 2)
			goto not_lurk_server;
		if(extlen)
			recv(skt, general_buffer, extlen, MSG_WAITALL);
		sprintf(error_buffer, RED("Terminated while waiting for game on lurk server version %d.%d on port %d\n"), major, minor, current_port);	
		if(!read(skt, &type, 1))
			goto bad_lurk_server;
		alarm(0);
	}
	uint16_t game_numbers[3];
	if(11 == type){
		current_error = error_buffer;
		sprintf(error_buffer, RED("Terminated while waiting after receiving type 11 %u on port %d\n"), game_numbers[2], current_port);
		alarm(1);
		if(6 != recv(skt, game_numbers, 6, MSG_WAITALL))
			goto not_lurk_server;
		sprintf(error_buffer, RED("Terminated waiting for game description of length %u on port %d\n"), game_numbers[2], current_port);
		ssize_t readlen = recv(skt, general_buffer, game_numbers[2], MSG_WAITALL);
		alarm(0);
		if(readlen != game_numbers[2])
			goto bad_lurk_server;
		general_buffer[readlen] = 0;
	} else 
		goto not_lurk_server;
	if(!quiet){
		printf(GREEN("Found lurk server on port %u:\n"), cport);
		printf("Version %u.%u with %u bytes of extensions\n", major, minor);
		printf("Game has %u initial points, %u stat limit, description:  %s\n", game_numbers[0], game_numbers[1], general_buffer);
	}
	close(skt);
	return 0;
bad_lurk_server:
	if(!quiet)
		printf(YELLOW("Port %u is open, and might have a lurk server that isn't following the protocol correctly.\n"), cport);
	close(skt);
	return 1;

not_lurk_server:
	if(!quiet)
		printf(YELLOW("Port %u is open, but does not seem to be a lurk server\n"), cport);
	close(skt);
	return 1;
}


// Parameters will be port range
int main(int argc, char ** argv){
	struct sigaction sa;
	sa.sa_handler = handle_alarm;
	sigaction(SIGALRM, &sa, 0);

	uint16_t low_port = 5000;
	uint16_t high_port = 5200;
	char* hostname = "isoptera.lcsc.edu";
	
	if(argc == 2){
		low_port = atoi(argv[1]);
		high_port = low_port;
	}
	if(argc == 3){
		low_port = atoi(argv[1]);
		high_port = atoi(argv[2]);
	}
		

	for(uint16_t cport = low_port; cport <= high_port; cport++){
		check_for_server(hostname, cport, 0);	
	}
	return 0;
}