#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>
#include "util.h"

/* ==================== Static Data ==================== */

#ifdef WINDOWS
/* Info written when starting up WinSock */
WSADATA wsadata;
#else
/* Terminal settings for getch emulation */
struct termios oldterm, newterm;
#endif


/* ==================== Set-up and Tear-down ==================== */

int util_init() {
    #ifdef WINDOWS
    WSAStartup(MAKEWORD(2, 2), &wsadata);
    #else
    tcgetattr(STDIN_FILENO, &oldterm);
    newterm = oldterm;
    newterm.c_lflag &= ~(ICANON | ECHO);
    tcsetattr(STDIN_FILENO, TCSANOW, &newterm);
    #endif
    return 0;
}

void util_cleanup() {
    #ifdef WINDOWS
    WSACleanup();
    #else
    tcsetattr(STDIN_FILENO, TCSANOW, &oldterm);
    #endif
}


/* ==================== Thread Interface ==================== */

int thread_create(Thread *thread, ThreadFunc func, ThreadArg arg) {
    assert(thread);
    assert(func);
    #ifdef WINDOWS
    *thread = CreateThread(NULL, 0, func, arg, 0, NULL);
    #else
    pthread_create(thread, NULL, func, arg);
    #endif
    return 0;
}

void thread_destroy(Thread *thread) {
    #ifdef WINDOWS
    CloseHandle(*thread);
    #endif
}

void thread_join(Thread *thread) {
    #ifdef WINDOWS
    WaitForSingleObject(*thread, INFINITE);
    #else
    pthread_join(*thread, NULL);
    #endif
}


/* ==================== Socket Interface ==================== */

int socket_open(Socket *sock, const char *hostname, const char *port) {
    struct addrinfo *info, hints;
    int result;
    assert(sock);
    assert(port);
    memset(&hints, 0, sizeof(struct addrinfo));
    hints.ai_family = AF_INET;
    hints.ai_socktype = SOCK_STREAM;
    hints.ai_protocol = IPPROTO_TCP;
    result = getaddrinfo(hostname, port, &hints, &info);
    if (result == 0) {
        *sock = socket(info->ai_family, info->ai_socktype, info->ai_protocol);
        if (*sock == INVALID_SOCKET)
            socket_close(sock);
        else
            result = connect(*sock, info->ai_addr, info->ai_addrlen);
        freeaddrinfo(info);
    }
    return result;
}

int socket_server(Socket *sock, const char *port) {
    struct addrinfo *info, hints;
    int result;
    assert(sock);
    assert(port);
    memset(&hints, 0, sizeof(struct addrinfo));
    hints.ai_family = AF_INET;
    hints.ai_socktype = SOCK_STREAM;
    hints.ai_protocol = IPPROTO_TCP;
    hints.ai_flags = AI_PASSIVE;
    result = getaddrinfo(NULL, port, &hints, &info);
    if (result == 0) {
        *sock = socket(info->ai_family, info->ai_socktype, info->ai_protocol);
        if (*sock == INVALID_SOCKET)
            socket_close(sock);
        else {
            result = bind(*sock, info->ai_addr, info->ai_addrlen);
            if (result != 0)
                socket_close(sock);
            else
                result = listen(*sock, 1);
        }
        freeaddrinfo(info);
    }
    return result;
}

int socket_accept(Socket *sock, Socket *client) {
    assert(sock);
    assert(client);
    *client = accept(*sock, NULL, NULL);
    if (*client == INVALID_SOCKET)
        return -1;
    return 0;
}

void socket_close(Socket *sock) {
    assert(sock);
    #ifdef WINDOWS
    /*shutdown(*sock, SD_BOTH);*/
    closesocket(*sock);
    #else
    /*shutdown(*sock, SHUT_RDWR);*/
    close(*sock);
    #endif
}

int socket_write(Socket *sock, const char *buffer, size_t count) {
    assert(sock);
    assert(buffer);
    #ifdef WINDOWS
    return send(*sock, buffer, count, 0);
    #else
    return write(*sock, buffer, count);
    #endif
}

int socket_read(Socket *sock, char *buffer, size_t count) {
    assert(sock);
    assert(buffer);
    #ifdef WINDOWS
    return recv(*sock, buffer, count, 0);
    #else
    return read(*sock, buffer, count);
    #endif
}


/* ==================== Minor Interface ==================== */

void sleep_ms(unsigned int ms) {
    #ifdef WINDOWS
    Sleep(ms);
    #else
    while (ms >= 1000) {
        sleep(1);
        ms -= 1000;
    }
    if (ms > 0)
        usleep(ms * 1000);
    #endif
}

void emit_beep(unsigned int val) {
    #ifdef WINDOWS
    /* Compute a value somewhere in [37, 32767] based on the 8 LSB of 'val'.
       However, the following function will not work for XP-64bit or Vista. */
    DWORD freq = (25000.0 / 256) * val + 37;
    Beep(freq, BEEP_DURATION);
    #else
    /* In my tests, I could not get ioctl() to work with producing variable
       tones, and even then, it might require root access. This monotone beep
       will hopefully be replaced soon for POSIX systems. */
    putchar('\a');
    #endif
}