/*
  ==============================================================================

   This file is part of the juce_core module of the JUCE library.
   Copyright (c) 2013 - Raw Material Software Ltd.

   Permission to use, copy, modify, and/or distribute this software for any purpose with
   or without fee is hereby granted, provided that the above copyright notice and this
   permission notice appear in all copies.

   THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD
   TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN
   NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
   DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
   IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
   CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

   ------------------------------------------------------------------------------

   NOTE! This permissive ISC license applies ONLY to files within the juce_core module!
   All other JUCE modules are covered by a dual GPL/commercial license, so if you are
   using any other modules, be sure to check that you also comply with their license.

   For more details, visit www.juce.com

  ==============================================================================
*/

#if JUCE_MSVC
 #pragma warning (push)
 #pragma warning (disable : 4127 4389 4018)
#endif

#ifndef AI_NUMERICSERV  // (missing in older Mac SDKs)
 #define AI_NUMERICSERV 0x1000
#endif

#if JUCE_WINDOWS
 typedef int       juce_socklen_t;
 typedef SOCKET    SocketHandle;
#else
 typedef socklen_t juce_socklen_t;
 typedef int       SocketHandle;
#endif

//==============================================================================
namespace SocketHelpers
{
    static void initSockets()
    {
       #if JUCE_WINDOWS
        static bool socketsStarted = false;

        if (! socketsStarted)
        {
            socketsStarted = true;

            WSADATA wsaData;
            const WORD wVersionRequested = MAKEWORD (1, 1);
            WSAStartup (wVersionRequested, &wsaData);
        }
       #endif
    }

    static bool resetSocketOptions (const SocketHandle handle, const bool isDatagram, const bool allowBroadcast) noexcept
    {
        const int sndBufSize = 65536;
        const int rcvBufSize = 65536;
        const int one = 1;

        return handle > 0
                && setsockopt (handle, SOL_SOCKET, SO_RCVBUF, (const char*) &rcvBufSize, sizeof (rcvBufSize)) == 0
                && setsockopt (handle, SOL_SOCKET, SO_SNDBUF, (const char*) &sndBufSize, sizeof (sndBufSize)) == 0
                && (isDatagram ? ((! allowBroadcast) || setsockopt (handle, SOL_SOCKET, SO_BROADCAST, (const char*) &one, sizeof (one)) == 0)
                               : (setsockopt (handle, IPPROTO_TCP, TCP_NODELAY, (const char*) &one, sizeof (one)) == 0));
    }

    static bool bindSocketToPort (const SocketHandle handle, const int port) noexcept
    {
        if (handle <= 0 || port <= 0)
            return false;

        struct sockaddr_in servTmpAddr;
        zerostruct (servTmpAddr); // (can't use "= { 0 }" on this object because it's typedef'ed as a C struct)
        servTmpAddr.sin_family = PF_INET;
        servTmpAddr.sin_addr.s_addr = htonl (INADDR_ANY);
        servTmpAddr.sin_port = htons ((uint16) port);

        return bind (handle, (struct sockaddr*) &servTmpAddr, sizeof (struct sockaddr_in)) >= 0;
    }

    static int readSocket (const SocketHandle handle,
                           void* const destBuffer, const int maxBytesToRead,
                           bool volatile& connected,
                           const bool blockUntilSpecifiedAmountHasArrived) noexcept
    {
        int bytesRead = 0;

        while (bytesRead < maxBytesToRead)
        {
            int bytesThisTime;

           #if JUCE_WINDOWS
            bytesThisTime = recv (handle, static_cast<char*> (destBuffer) + bytesRead, maxBytesToRead - bytesRead, 0);
           #else
            while ((bytesThisTime = (int) ::read (handle, addBytesToPointer (destBuffer, bytesRead),
                                                  (size_t) (maxBytesToRead - bytesRead))) < 0
                     && errno == EINTR
                     && connected)
            {
            }
           #endif

            if (bytesThisTime <= 0 || ! connected)
            {
                if (bytesRead == 0)
                    bytesRead = -1;

                break;
            }

            bytesRead += bytesThisTime;

            if (! blockUntilSpecifiedAmountHasArrived)
                break;
        }

        return bytesRead;
    }

    static int waitForReadiness (const SocketHandle handle, const bool forReading, const int timeoutMsecs) noexcept
    {
        struct timeval timeout;
        struct timeval* timeoutp;

        if (timeoutMsecs >= 0)
        {
            timeout.tv_sec = timeoutMsecs / 1000;
            timeout.tv_usec = (timeoutMsecs % 1000) * 1000;
            timeoutp = &timeout;
        }
        else
        {
            timeoutp = 0;
        }

        fd_set rset, wset;
        FD_ZERO (&rset);
        FD_SET (handle, &rset);
        FD_ZERO (&wset);
        FD_SET (handle, &wset);

        fd_set* const prset = forReading ? &rset : nullptr;
        fd_set* const pwset = forReading ? nullptr : &wset;

       #if JUCE_WINDOWS
        if (select ((int) handle + 1, prset, pwset, 0, timeoutp) < 0)
            return -1;
       #else
        {
            int result;
            while ((result = select (handle + 1, prset, pwset, 0, timeoutp)) < 0
                    && errno == EINTR)
            {
            }

            if (result < 0)
                return -1;
        }
       #endif

        {
            int opt;
            juce_socklen_t len = sizeof (opt);

            if (getsockopt (handle, SOL_SOCKET, SO_ERROR, (char*) &opt, &len) < 0
                 || opt != 0)
                return -1;
        }

        return FD_ISSET (handle, forReading ? &rset : &wset) ? 1 : 0;
    }

    static bool setSocketBlockingState (const SocketHandle handle, const bool shouldBlock) noexcept
    {
       #if JUCE_WINDOWS
        u_long nonBlocking = shouldBlock ? 0 : (u_long) 1;
        return ioctlsocket (handle, FIONBIO, &nonBlocking) == 0;
       #else
        int socketFlags = fcntl (handle, F_GETFL, 0);

        if (socketFlags == -1)
            return false;

        if (shouldBlock)
            socketFlags &= ~O_NONBLOCK;
        else
            socketFlags |= O_NONBLOCK;

        return fcntl (handle, F_SETFL, socketFlags) == 0;
       #endif
    }

    static bool connectSocket (int volatile& handle,
                               const bool isDatagram,
                               struct addrinfo** const serverAddress,
                               const String& hostName,
                               const int portNumber,
                               const int timeOutMillisecs) noexcept
    {
        struct addrinfo hints;
        zerostruct (hints);

        hints.ai_family = AF_UNSPEC;
        hints.ai_socktype = isDatagram ? SOCK_DGRAM : SOCK_STREAM;
        hints.ai_flags = AI_NUMERICSERV;

        struct addrinfo* info = nullptr;
        if (getaddrinfo (hostName.toUTF8(), String (portNumber).toUTF8(), &hints, &info) != 0
             || info == nullptr)
            return false;

        if (handle < 0)
            handle = (int) socket (info->ai_family, info->ai_socktype, 0);

        if (handle < 0)
        {
            freeaddrinfo (info);
            return false;
        }

        if (isDatagram)
        {
            if (*serverAddress != nullptr)
                freeaddrinfo (*serverAddress);

            *serverAddress = info;
            return true;
        }

        setSocketBlockingState (handle, false);
        const int result = ::connect (handle, info->ai_addr, (socklen_t) info->ai_addrlen);
        freeaddrinfo (info);

        if (result < 0)
        {
           #if JUCE_WINDOWS
            if (result == SOCKET_ERROR && WSAGetLastError() == WSAEWOULDBLOCK)
           #else
            if (errno == EINPROGRESS)
           #endif
            {
                if (waitForReadiness (handle, false, timeOutMillisecs) != 1)
                {
                    setSocketBlockingState (handle, true);
                    return false;
                }
            }
        }

        setSocketBlockingState (handle, true);
        resetSocketOptions (handle, false, false);

        return true;
    }

    static void makeReusable (int handle) noexcept
    {
        const int reuse = 1;
        setsockopt (handle, SOL_SOCKET, SO_REUSEADDR, (const char*) &reuse, sizeof (reuse));
    }
}

//==============================================================================
StreamingSocket::StreamingSocket()
    : portNumber (0),
      handle (-1),
      connected (false),
      isListener (false)
{
    SocketHelpers::initSockets();
}

StreamingSocket::StreamingSocket (const String& host, int portNum, int h)
    : hostName (host),
      portNumber (portNum),
      handle (h),
      connected (true),
      isListener (false)
{
    SocketHelpers::initSockets();
    SocketHelpers::resetSocketOptions (h, false, false);
}

StreamingSocket::~StreamingSocket()
{
    close();
}

//==============================================================================
int StreamingSocket::read (void* destBuffer, const int maxBytesToRead,
                           const bool blockUntilSpecifiedAmountHasArrived)
{
    return (connected && ! isListener) ? SocketHelpers::readSocket (handle, destBuffer, maxBytesToRead,
                                                                    connected, blockUntilSpecifiedAmountHasArrived)
                                       : -1;
}

int StreamingSocket::write (const void* sourceBuffer, const int numBytesToWrite)
{
    if (isListener || ! connected)
        return -1;

   #if JUCE_WINDOWS
    return send (handle, (const char*) sourceBuffer, numBytesToWrite, 0);
   #else
    int result;

    while ((result = (int) ::write (handle, sourceBuffer, (size_t) numBytesToWrite)) < 0
            && errno == EINTR)
    {
    }

    return result;
   #endif
}

//==============================================================================
int StreamingSocket::waitUntilReady (const bool readyForReading,
                                     const int timeoutMsecs) const
{
    return connected ? SocketHelpers::waitForReadiness (handle, readyForReading, timeoutMsecs)
                     : -1;
}

//==============================================================================
bool StreamingSocket::bindToPort (const int port)
{
    return SocketHelpers::bindSocketToPort (handle, port);
}

bool StreamingSocket::connect (const String& remoteHostName,
                               const int remotePortNumber,
                               const int timeOutMillisecs)
{
    if (isListener)
    {
        jassertfalse;    // a listener socket can't connect to another one!
        return false;
    }

    if (connected)
        close();

    hostName = remoteHostName;
    portNumber = remotePortNumber;
    isListener = false;

    connected = SocketHelpers::connectSocket (handle, false, nullptr, remoteHostName,
                                              remotePortNumber, timeOutMillisecs);

    if (! (connected && SocketHelpers::resetSocketOptions (handle, false, false)))
    {
        close();
        return false;
    }

    return true;
}

void StreamingSocket::close()
{
   #if JUCE_WINDOWS
    if (handle != SOCKET_ERROR || connected)
        closesocket (handle);

    connected = false;
   #else
    if (connected)
    {
        connected = false;

        if (isListener)
        {
            // need to do this to interrupt the accept() function..
            StreamingSocket temp;
            temp.connect (IPAddress::local().toString(), portNumber, 1000);
        }
    }

    if (handle != -1)
        ::close (handle);
   #endif

    hostName.clear();
    portNumber = 0;
    handle = -1;
    isListener = false;
}

//==============================================================================
bool StreamingSocket::createListener (const int newPortNumber, const String& localHostName)
{
    if (connected)
        close();

    hostName = "listener";
    portNumber = newPortNumber;
    isListener = true;

    struct sockaddr_in servTmpAddr;
    zerostruct (servTmpAddr);

    servTmpAddr.sin_family = PF_INET;
    servTmpAddr.sin_addr.s_addr = htonl (INADDR_ANY);

    if (localHostName.isNotEmpty())
        servTmpAddr.sin_addr.s_addr = ::inet_addr (localHostName.toUTF8());

    servTmpAddr.sin_port = htons ((uint16) portNumber);

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

    if (handle < 0)
        return false;

   #if ! JUCE_WINDOWS // on windows, adding this option produces behaviour different to posix
    SocketHelpers::makeReusable (handle);
   #endif

    if (bind (handle, (struct sockaddr*) &servTmpAddr, sizeof (struct sockaddr_in)) < 0
         || listen (handle, SOMAXCONN) < 0)
    {
        close();
        return false;
    }

    connected = true;
    return true;
}

StreamingSocket* StreamingSocket::waitForNextConnection() const
{
    // To call this method, you first have to use createListener() to
    // prepare this socket as a listener.
    jassert (isListener || ! connected);

    if (connected && isListener)
    {
        struct sockaddr_storage address;
        juce_socklen_t len = sizeof (address);
        const int newSocket = (int) accept (handle, (struct sockaddr*) &address, &len);

        if (newSocket >= 0 && connected)
            return new StreamingSocket (inet_ntoa (((struct sockaddr_in*) &address)->sin_addr),
                                        portNumber, newSocket);
    }

    return nullptr;
}

bool StreamingSocket::isLocal() const noexcept
{
    return hostName == "127.0.0.1";
}


//==============================================================================
//==============================================================================
DatagramSocket::DatagramSocket (const int localPortNumber, const bool canBroadcast)
    : portNumber (0),
      handle (-1),
      connected (true),
      allowBroadcast (canBroadcast),
      serverAddress (nullptr)
{
    SocketHelpers::initSockets();

    handle = (int) socket (AF_INET, SOCK_DGRAM, 0);
    SocketHelpers::makeReusable (handle);
    bindToPort (localPortNumber);
}

DatagramSocket::DatagramSocket (const String& host, const int portNum,
                                const int h, const int localPortNumber)
    : hostName (host),
      portNumber (portNum),
      handle (h),
      connected (true),
      allowBroadcast (false),
      serverAddress (nullptr)
{
    SocketHelpers::initSockets();

    SocketHelpers::resetSocketOptions (h, true, allowBroadcast);
    bindToPort (localPortNumber);
}

DatagramSocket::~DatagramSocket()
{
    close();

    if (serverAddress != nullptr)
        freeaddrinfo (static_cast <struct addrinfo*> (serverAddress));
}

void DatagramSocket::close()
{
   #if JUCE_WINDOWS
    closesocket (handle);
    connected = false;
   #else
    connected = false;
    ::close (handle);
   #endif

    hostName.clear();
    portNumber = 0;
    handle = -1;
}

bool DatagramSocket::bindToPort (const int port)
{
    return SocketHelpers::bindSocketToPort (handle, port);
}

bool DatagramSocket::connect (const String& remoteHostName,
                              const int remotePortNumber,
                              const int timeOutMillisecs)
{
    if (connected)
        close();

    hostName = remoteHostName;
    portNumber = remotePortNumber;

    connected = SocketHelpers::connectSocket (handle, true, (struct addrinfo**) &serverAddress,
                                              remoteHostName, remotePortNumber,
                                              timeOutMillisecs);

    if (! (connected && SocketHelpers::resetSocketOptions (handle, true, allowBroadcast)))
    {
        close();
        return false;
    }

    return true;
}

DatagramSocket* DatagramSocket::waitForNextConnection() const
{
    while (waitUntilReady (true, -1) == 1)
    {
        struct sockaddr_storage address;
        juce_socklen_t len = sizeof (address);
        char buf[1];

        if (recvfrom (handle, buf, 0, 0, (struct sockaddr*) &address, &len) > 0)
            return new DatagramSocket (inet_ntoa (((struct sockaddr_in*) &address)->sin_addr),
                                       ntohs (((struct sockaddr_in*) &address)->sin_port),
                                       -1, -1);
    }

    return nullptr;
}

//==============================================================================
int DatagramSocket::waitUntilReady (const bool readyForReading,
                                    const int timeoutMsecs) const
{
    return connected ? SocketHelpers::waitForReadiness (handle, readyForReading, timeoutMsecs)
                     : -1;
}

int DatagramSocket::read (void* destBuffer, const int maxBytesToRead, const bool blockUntilSpecifiedAmountHasArrived)
{
    return connected ? SocketHelpers::readSocket (handle, destBuffer, maxBytesToRead,
                                                  connected, blockUntilSpecifiedAmountHasArrived)
                     : -1;
}

int DatagramSocket::write (const void* sourceBuffer, const int numBytesToWrite)
{
    // You need to call connect() first to set the server address..
    jassert (serverAddress != nullptr && connected);

    return connected ? (int) sendto (handle, (const char*) sourceBuffer,
                                     (size_t) numBytesToWrite, 0,
                                     static_cast <const struct addrinfo*> (serverAddress)->ai_addr,
                                     (juce_socklen_t) static_cast <const struct addrinfo*> (serverAddress)->ai_addrlen)
                     : -1;
}

bool DatagramSocket::isLocal() const noexcept
{
    return hostName == "127.0.0.1";
}

#if JUCE_MSVC
 #pragma warning (pop)
#endif
