#include <iostream>
#include <sstream>
#include <string>
#include <cstring>
#include <cstdlib>
#include <unistd.h>
#include <signal.h>
#include <errno.h>
#include <sys/socket.h>
#include <sys/types.h>
#include <netinet/in.h>
#include <arpa/inet.h>

#define BUFFER_SIZE 256
#define NOSERVER_RET 10
#define INVALID_PORT_RET 20
#define BINDERR_RET 25
#define CONN_FAILED_RET 30

using namespace std;

int sockfd = 0;

void clean_up(int signum) {
    if (sockfd == -1) exit(1);

    shutdown(sockfd, SHUT_RDWR);
    close(sockfd);

    exit(0);
}

int main(int argc, char const *argv[]) {
    signal(SIGINT, clean_up);
    // no server info specified
    if (argc < 2) {
        cerr << "No server info provided!" << endl << "Usage: client <ip> <port>" << endl;
        return NOSERVER_RET;
    }

    int port = atoi(argv[2]);
    if (port < 0 || port >= 65536) {
        cerr << "Invalid port! port range: 0 ~ 65535" << endl;
        return INVALID_PORT_RET;
    }

    struct sockaddr_in info;
    struct sockaddr_in client_info;

    // create tcp socket
    sockfd = socket(AF_INET, SOCK_STREAM, 0);
    if (sockfd == -1) {
        cerr << "Failed to create socket." << endl;
        clean_up(0);
        exit(errno);
    }

    int truthy = 1;
    setsockopt(sockfd, SOL_SOCKET, SO_REUSEPORT, &truthy, sizeof(int));
    setsockopt(sockfd, SOL_SOCKET, SO_REUSEADDR, &truthy, sizeof(int));

    // setup server info
    bzero(&client_info, sizeof(client_info));
    client_info.sin_family = PF_INET;
    client_info.sin_addr.s_addr = INADDR_ANY;
    client_info.sin_port = htons(48763);

    // use static client port
    if (bind(sockfd, (struct sockaddr *) &client_info, sizeof(client_info)) == -1) {
        cerr << "socket bind error" << endl;
        // close(sockfd);
        exit(errno);
    }

    // setup server info
    bzero(&info, sizeof(info));
    info.sin_family = PF_INET;
    info.sin_addr.s_addr = inet_addr(argv[1]);
    info.sin_port = htons(port);

    if (connect(sockfd, (struct sockaddr *) &info, sizeof(info)) == -1) {
        cerr << "Connection failed." << endl;
        // close(sockfd);
        exit(errno);
    }

    cout << "--------------" << endl;
    cout << "  Game start  " << endl;
    cout << "--------------" << endl;

    while (true) {
        // ask for input
        cout << "Guess: ";
        string number;
        cin >> number;

        // create payload
        const char * msg = number.c_str();

        #ifdef DEBUG
        cout << msg << endl;
        #endif

        if (send(sockfd, msg, sizeof(msg), 0) == -1) {
            cerr << "Send error" << endl;
            clean_up(0);
            exit(errno);
        };

        // receive server response
        char buffer[BUFFER_SIZE];
        memset(buffer, 0, sizeof(buffer));
        int size = recv(sockfd, buffer, sizeof(buffer), 0);
        if (size <= 0) {
            cout << "Connection ended." << endl;
            break;
        }

        #ifdef DEBUG
        cout << buffer << endl;
        #endif

        // parse message from server
        stringstream ss(buffer);
        string lower, upper, count;
        getline(ss, lower, ':');
        getline(ss, upper, ':');
        getline(ss, count, ':');

        if (lower == upper) {
            // win, start new turn
            cout << "Answer Correct. Guessed for " << count << " times." << endl;
            cout << endl;
            cout << "--------------" << endl;
            cout << "   New Turn   " << endl;
            cout << "--------------" << endl;
            continue;
        }

        cout << "Answer is fewer than " << upper << endl;
        cout << "Answer is more than " << lower << endl;
        // space
        cout << endl;
    }

    close(sockfd);
    return 0;
}