/*

 This file is a part of JRTPLIB
 Copyright (c) 1999-2017 Jori Liesenborgs

 Contact: jori.liesenborgs@gmail.com

 This library was developed at the Expertise Centre for Digital Media
 (http://www.edm.uhasselt.be), a research center of the Hasselt University
 (http://www.uhasselt.be). The library is based upon work done for
 my thesis at the School for Knowledge Technology (Belgium/The Netherlands).

 Permission is hereby granted, free of charge, to any person obtaining a
 copy of this software and associated documentation files (the "Software"),
 to deal in the Software without restriction, including without limitation
 the rights to use, copy, modify, merge, publish, distribute, sublicense,
 and/or sell copies of the Software, and to permit persons to whom the
 Software is furnished to do so, subject to the following conditions:

 The above copyright notice and this permission notice shall be included
 in all copies or substantial portions of the Software.

 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
 THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
 IN THE SOFTWARE.

 */

#include "rtptcptransmitter.h"
#include "rtprawpacket.h"
#include "rtptcpaddress.h"
#include "rtptimeutilities.h"
#include "rtpdefines.h"
#include "rtpstructs.h"
#include "rtpsocketutilinternal.h"
#include "rtpinternalutils.h"
#include "rtpselect.h"
#include <stdio.h>
#include <assert.h>
#include <vector>

#include <iostream>

using namespace std;

#define RTPTCPTRANS_MAXPACKSIZE	65535

namespace qrtplib
{

RTPTCPTransmitter::RTPTCPTransmitter()
{
    m_created = false;
    m_init = false;
}

RTPTCPTransmitter::~RTPTCPTransmitter()
{
    Destroy();
}

int RTPTCPTransmitter::Init(bool tsafe)
{
    if (m_init)
        return ERR_RTP_TCPTRANS_ALREADYINIT;

    if (tsafe)
        return ERR_RTP_NOTHREADSUPPORT;

    m_maxPackSize = RTPTCPTRANS_MAXPACKSIZE;
    m_init = true;
    return 0;
}

int RTPTCPTransmitter::Create(size_t maximumpacketsize __attribute__((unused)), const RTPTransmissionParams *transparams)
{
    const RTPTCPTransmissionParams *params, defaultparams;
    int status;

    if (!m_init)
        return ERR_RTP_TCPTRANS_NOTINIT;

    if (m_created)
    {
        return ERR_RTP_TCPTRANS_ALREADYCREATED;
    }

    // Obtain transmission parameters

    if (transparams == 0)
        params = &defaultparams;
    else
    {
        if (transparams->GetTransmissionProtocol() != RTPTransmitter::TCPProto)
        {
            return ERR_RTP_TCPTRANS_ILLEGALPARAMETERS;
        }
        params = static_cast<const RTPTCPTransmissionParams *>(transparams);
    }

    if (!params->GetCreatedAbortDescriptors())
    {
        if ((status = m_abortDesc.Init()) < 0)
        {
            return status;
        }
        m_pAbortDesc = &m_abortDesc;
    }
    else
    {
        m_pAbortDesc = params->GetCreatedAbortDescriptors();
        if (!m_pAbortDesc->IsInitialized())
        {
            return ERR_RTP_ABORTDESC_NOTINIT;
        }
    }

    m_waitingForData = false;
    m_created = true;
    return 0;
}

void RTPTCPTransmitter::Destroy()
{
    if (!m_init)
        return;

    if (!m_created)
    {
        return;
    }

    ClearDestSockets();
    FlushPackets();
    m_created = false;

    if (m_waitingForData)
    {
        m_pAbortDesc->SendAbortSignal();
        m_abortDesc.Destroy(); // Doesn't do anything if not initialized
        // to make sure that the WaitForIncomingData function ended

    }
    else
        m_abortDesc.Destroy(); // Doesn't do anything if not initialized

}

RTPTransmissionInfo *RTPTCPTransmitter::GetTransmissionInfo()
{
    if (!m_init)
        return 0;

    RTPTransmissionInfo *tinf = new RTPTCPTransmissionInfo();
    return tinf;
}

void RTPTCPTransmitter::DeleteTransmissionInfo(RTPTransmissionInfo *i)
{
    if (!m_init)
        return;

    delete i;
}

int RTPTCPTransmitter::GetLocalHostName(uint8_t *buffer, size_t *bufferlength)
{
    if (!m_init)
        return ERR_RTP_TCPTRANS_NOTINIT;

    if (!m_created)
    {
        return ERR_RTP_TCPTRANS_NOTCREATED;
    }

    if (m_localHostname.size() == 0)
    {
//
// TODO
// TODO
// TODO
// TODO
//
        m_localHostname.resize(9);
        memcpy(&m_localHostname[0], "localhost", m_localHostname.size());
    }

    if ((*bufferlength) < m_localHostname.size())
    {
        *bufferlength = m_localHostname.size(); // tell the application the required size of the buffer
        return ERR_RTP_TRANS_BUFFERLENGTHTOOSMALL;
    }

    memcpy(buffer, &m_localHostname[0], m_localHostname.size());
    *bufferlength = m_localHostname.size();

    return 0;
}

bool RTPTCPTransmitter::ComesFromThisTransmitter(const RTPAddress *addr)
{
    if (!m_init)
        return false;

    if (addr == 0)
        return false;

    if (!m_created)
        return false;

    if (addr->GetAddressType() != RTPAddress::TCPAddress)
        return false;

    bool v = false;

    // TODO: for now, we're assuming that we can't just send to the same transmitter

    return v;
}

int RTPTCPTransmitter::Poll()
{
    if (!m_init)
        return ERR_RTP_TCPTRANS_NOTINIT;

    if (!m_created)
    {
        return ERR_RTP_TCPTRANS_NOTCREATED;
    }

    std::map<SocketType, SocketData>::iterator it = m_destSockets.begin();
    std::map<SocketType, SocketData>::iterator end = m_destSockets.end();
    int status = 0;

    vector<SocketType> errSockets;

    while (it != end)
    {
        SocketType sock = it->first;
        status = PollSocket(sock, it->second);
        if (status < 0)
        {
            // Stop immediately on out of memory
            if (status == ERR_RTP_OUTOFMEM)
                break;
            else
            {
                errSockets.push_back(sock);
                // Don't let this count as an error (due to a closed connection for example),
                // otherwise the poll thread (if used) will stop because of this. Since there
                // may be more than one connection, that's not desirable in general.
                status = 0;
            }
        }
        ++it;
    }

    for (size_t i = 0; i < errSockets.size(); i++)
        OnReceiveError(errSockets[i]);

    return status;
}

int RTPTCPTransmitter::WaitForIncomingData(const RTPTime &delay, bool *dataavailable)
{
    if (!m_init)
        return ERR_RTP_TCPTRANS_NOTINIT;

    if (!m_created)
    {
        return ERR_RTP_TCPTRANS_NOTCREATED;
    }
    if (m_waitingForData)
    {
        return ERR_RTP_TCPTRANS_ALREADYWAITING;
    }

    m_tmpSocks.resize(m_destSockets.size() + 1);
    m_tmpFlags.resize(m_tmpSocks.size());
    SocketType abortSocket = m_pAbortDesc->GetAbortSocket();

    std::map<SocketType, SocketData>::iterator it = m_destSockets.begin();
    std::map<SocketType, SocketData>::iterator end = m_destSockets.end();
    int idx = 0;

    while (it != end)
    {
        m_tmpSocks[idx] = it->first;
        m_tmpFlags[idx] = 0;
        ++it;
        idx++;
    }
    m_tmpSocks[idx] = abortSocket;
    m_tmpFlags[idx] = 0;
    int idxAbort = idx;

    m_waitingForData = true;

    //cout << "Waiting for " << delay.GetDouble() << " seconds for data on " << m_tmpSocks.size() << " sockets" << endl;
    int status = RTPSelect(&m_tmpSocks[0], &m_tmpFlags[0], m_tmpSocks.size(), delay);
    if (status < 0)
    {
        m_waitingForData = false;

        return status;
    }

    m_waitingForData = false;
    if (!m_created) // destroy called
    {

        return 0;
    }

    // if aborted, read from abort buffer
    if (m_tmpFlags[idxAbort])
        m_pAbortDesc->ReadSignallingByte();

    if (dataavailable != 0)
    {
        bool avail = false;

        for (size_t i = 0; i < m_tmpFlags.size(); i++)
        {
            if (m_tmpFlags[i])
            {
                avail = true;
                //cout << "Data available!" << endl;
                break;
            }
        }

        if (avail)
            *dataavailable = true;
        else
            *dataavailable = false;
    }

    return 0;
}

int RTPTCPTransmitter::AbortWait()
{
    if (!m_init)
        return ERR_RTP_TCPTRANS_NOTINIT;

    if (!m_created)
    {
        return ERR_RTP_TCPTRANS_NOTCREATED;
    }
    if (!m_waitingForData)
    {
        return ERR_RTP_TCPTRANS_NOTWAITING;
    }

    m_pAbortDesc->SendAbortSignal();

    return 0;
}

int RTPTCPTransmitter::SendRTPData(const void *data, size_t len)
{
    return SendRTPRTCPData(data, len);
}

int RTPTCPTransmitter::SendRTCPData(const void *data, size_t len)
{
    return SendRTPRTCPData(data, len);
}

int RTPTCPTransmitter::AddDestination(const RTPAddress &addr)
{
    if (!m_init)
        return ERR_RTP_TCPTRANS_NOTINIT;

    if (!m_created)
    {
        return ERR_RTP_TCPTRANS_NOTCREATED;
    }

    if (addr.GetAddressType() != RTPAddress::TCPAddress)
    {
        return ERR_RTP_TCPTRANS_INVALIDADDRESSTYPE;
    }

    const RTPTCPAddress &a = static_cast<const RTPTCPAddress &>(addr);
    SocketType s = a.GetSocket();
    if (s == 0)
    {
        return ERR_RTP_TCPTRANS_NOSOCKETSPECIFIED;
    }

    int status = ValidateSocket(s);
    if (status != 0)
    {

        return status;
    }

    std::map<SocketType, SocketData>::iterator it = m_destSockets.find(s);
    if (it != m_destSockets.end())
    {

        return ERR_RTP_TCPTRANS_SOCKETALREADYINDESTINATIONS;
    }
    m_destSockets[s] = SocketData();

    // Because the sockets are also used for incoming data, we'll abort a wait
    // that may be in progress, otherwise it could take a few seconds until the
    // new socket is monitored for incoming data
    m_pAbortDesc->SendAbortSignal();

    return 0;
}

int RTPTCPTransmitter::DeleteDestination(const RTPAddress &addr)
{
    if (!m_init)
        return ERR_RTP_TCPTRANS_NOTINIT;

    if (!m_created)
    {

        return ERR_RTP_TCPTRANS_NOTCREATED;
    }

    if (addr.GetAddressType() != RTPAddress::TCPAddress)
    {

        return ERR_RTP_TCPTRANS_INVALIDADDRESSTYPE;
    }

    const RTPTCPAddress &a = static_cast<const RTPTCPAddress &>(addr);
    SocketType s = a.GetSocket();
    if (s == 0)
    {

        return ERR_RTP_TCPTRANS_NOSOCKETSPECIFIED;
    }

    std::map<SocketType, SocketData>::iterator it = m_destSockets.find(s);
    if (it == m_destSockets.end())
    {

        return ERR_RTP_TCPTRANS_SOCKETNOTFOUNDINDESTINATIONS;
    }

    // Clean up possibly allocated memory
    uint8_t *pBuf = it->second.ExtractDataBuffer();
    if (pBuf)
        delete[] pBuf;

    m_destSockets.erase(it);

    return 0;
}

void RTPTCPTransmitter::ClearDestinations()
{
    if (!m_init)
        return;

    if (m_created)
        ClearDestSockets();

}

bool RTPTCPTransmitter::SupportsMulticasting()
{
    return false;
}

int RTPTCPTransmitter::JoinMulticastGroup(const RTPAddress &)
{
    return ERR_RTP_TCPTRANS_NOMULTICASTSUPPORT;
}

int RTPTCPTransmitter::LeaveMulticastGroup(const RTPAddress &)
{
    return ERR_RTP_TCPTRANS_NOMULTICASTSUPPORT;
}

void RTPTCPTransmitter::LeaveAllMulticastGroups()
{
}

int RTPTCPTransmitter::SetReceiveMode(RTPTransmitter::ReceiveMode m)
{
    if (m != RTPTransmitter::AcceptAll)
        return ERR_RTP_TCPTRANS_RECEIVEMODENOTSUPPORTED;
    return 0;
}

int RTPTCPTransmitter::AddToIgnoreList(const RTPAddress &)
{
    return ERR_RTP_TCPTRANS_RECEIVEMODENOTSUPPORTED;
}

int RTPTCPTransmitter::DeleteFromIgnoreList(const RTPAddress &)
{
    return ERR_RTP_TCPTRANS_RECEIVEMODENOTSUPPORTED;
}

void RTPTCPTransmitter::ClearIgnoreList()
{
}

int RTPTCPTransmitter::AddToAcceptList(const RTPAddress &)
{
    return ERR_RTP_TCPTRANS_RECEIVEMODENOTSUPPORTED;
}

int RTPTCPTransmitter::DeleteFromAcceptList(const RTPAddress &)
{
    return ERR_RTP_TCPTRANS_RECEIVEMODENOTSUPPORTED;
}

void RTPTCPTransmitter::ClearAcceptList()
{
}

int RTPTCPTransmitter::SetMaximumPacketSize(size_t s)
{
    if (!m_init)
        return ERR_RTP_TCPTRANS_NOTINIT;

    if (!m_created)
    {

        return ERR_RTP_TCPTRANS_NOTCREATED;
    }
    if (s > RTPTCPTRANS_MAXPACKSIZE)
    {

        return ERR_RTP_TCPTRANS_SPECIFIEDSIZETOOBIG;
    }
    m_maxPackSize = s;

    return 0;
}

bool RTPTCPTransmitter::NewDataAvailable()
{
    if (!m_init)
        return false;

    bool v;

    if (!m_created)
        v = false;
    else
    {
        if (m_rawpacketlist.empty())
            v = false;
        else
            v = true;
    }

    return v;
}

RTPRawPacket *RTPTCPTransmitter::GetNextPacket()
{
    if (!m_init)
        return 0;

    RTPRawPacket *p;

    if (!m_created)
    {

        return 0;
    }
    if (m_rawpacketlist.empty())
    {

        return 0;
    }

    p = *(m_rawpacketlist.begin());
    m_rawpacketlist.pop_front();

    return p;
}

// Here the private functions start...

void RTPTCPTransmitter::FlushPackets()
{
    std::list<RTPRawPacket*>::const_iterator it;

    for (it = m_rawpacketlist.begin(); it != m_rawpacketlist.end(); ++it)
        delete *it;
    m_rawpacketlist.clear();
}

int RTPTCPTransmitter::PollSocket(SocketType sock, SocketData &sdata)
{
#ifdef RTP_SOCKETTYPE_WINSOCK
    unsigned long len;
#else
    size_t len;
#endif // RTP_SOCKETTYPE_WINSOCK
    bool dataavailable;

    do
    {
        len = 0;
        RTPIOCTL(sock, FIONREAD, &len);

        if (len <= 0)
            dataavailable = false;
        else
            dataavailable = true;

        if (dataavailable)
        {
            RTPTime curtime = RTPTime::CurrentTime();
            int relevantLen = RTPTCPTRANS_MAXPACKSIZE + 2;

            if ((int) len < relevantLen)
                relevantLen = (int) len;

            bool complete = false;
            int status = sdata.ProcessAvailableBytes(sock, relevantLen, complete);
            if (status < 0)
                return status;

            if (complete)
            {
                uint8_t *pBuf = sdata.ExtractDataBuffer();
                if (pBuf)
                {
                    int dataLength = sdata.m_dataLength;
                    sdata.Reset();

                    RTPTCPAddress *pAddr = new RTPTCPAddress(sock);
                    if (pAddr == 0)
                        return ERR_RTP_OUTOFMEM;

                    bool isrtp = true;
                    if (dataLength > (int) sizeof(RTCPCommonHeader))
                    {
                        RTCPCommonHeader *rtcpheader = (RTCPCommonHeader *) pBuf;
                        uint8_t packettype = rtcpheader->packettype;

                        if (packettype >= 200 && packettype <= 204)
                            isrtp = false;
                    }

                    RTPRawPacket *pPack = new RTPRawPacket(pBuf, dataLength, pAddr, curtime, isrtp);
                    if (pPack == 0)
                    {
                        delete pAddr;
                        delete[] pBuf;
                        return ERR_RTP_OUTOFMEM;
                    }
                    m_rawpacketlist.push_back(pPack);
                }
            }
        }
    } while (dataavailable);

    return 0;
}

int RTPTCPTransmitter::SendRTPRTCPData(const void *data, size_t len)
{
    if (!m_init)
        return ERR_RTP_TCPTRANS_NOTINIT;

    if (!m_created)
    {

        return ERR_RTP_TCPTRANS_NOTCREATED;
    }
    if (len > RTPTCPTRANS_MAXPACKSIZE)
    {

        return ERR_RTP_TCPTRANS_SPECIFIEDSIZETOOBIG;
    }

    std::map<SocketType, SocketData>::iterator it = m_destSockets.begin();
    std::map<SocketType, SocketData>::iterator end = m_destSockets.end();

    vector<SocketType> errSockets;
    int flags = 0;
#ifdef RTP_HAVE_MSG_NOSIGNAL
    flags = MSG_NOSIGNAL;
#endif // RTP_HAVE_MSG_NOSIGNAL

    while (it != end)
    {
        uint8_t lengthBytes[2] =
        { (uint8_t) ((len >> 8) & 0xff), (uint8_t) (len & 0xff) };
        SocketType sock = it->first;

        if (send(sock, (const char *) lengthBytes, 2, flags) < 0 || send(sock, (const char *) data, len, flags) < 0)
            errSockets.push_back(sock);
        ++it;
    }

    if (errSockets.size() != 0)
    {
        for (size_t i = 0; i < errSockets.size(); i++)
            OnSendError(errSockets[i]);
    }

    // Don't return an error code to avoid the poll thread exiting
    // due to one closed connection for example

    return 0;
}

int RTPTCPTransmitter::ValidateSocket(SocketType)
{
    // TODO: should we even do a check (for a TCP socket)?
    return 0;
}

void RTPTCPTransmitter::ClearDestSockets()
{
    std::map<SocketType, SocketData>::iterator it = m_destSockets.begin();
    std::map<SocketType, SocketData>::iterator end = m_destSockets.end();

    while (it != end)
    {
        uint8_t *pBuf = it->second.ExtractDataBuffer();
        if (pBuf)
            delete[] pBuf;

        ++it;
    }
    m_destSockets.clear();
}

RTPTCPTransmitter::SocketData::SocketData()
{
    Reset();
}

void RTPTCPTransmitter::SocketData::Reset()
{
    m_lengthBufferOffset = 0;
    m_dataLength = 0;
    m_dataBufferOffset = 0;
    m_pDataBuffer = 0;
}

RTPTCPTransmitter::SocketData::~SocketData()
{
    assert(m_pDataBuffer == 0); // Should be deleted externally to avoid storing a memory manager in the class
}

int RTPTCPTransmitter::SocketData::ProcessAvailableBytes(SocketType sock, int availLen, bool &complete)
{

    const int numLengthBuffer = 2;
    if (m_lengthBufferOffset < numLengthBuffer) // first we need to get the length
    {
        assert(m_pDataBuffer == 0);
        int num = numLengthBuffer - m_lengthBufferOffset;
        if (num > availLen)
            num = availLen;

        int r = 0;
        if (num > 0)
        {
            r = (int) recv(sock, (char *) (m_lengthBuffer + m_lengthBufferOffset), num, 0);
            if (r < 0)
                return ERR_RTP_TCPTRANS_ERRORINRECV;
        }

        m_lengthBufferOffset += r;
        availLen -= r;

        assert(m_lengthBufferOffset <= numLengthBuffer);
        if (m_lengthBufferOffset == numLengthBuffer) // we can constuct a length
        {
            int l = 0;
            for (int i = numLengthBuffer - 1, shift = 0; i >= 0; i--, shift += 8)
                l |= ((int) m_lengthBuffer[i]) << shift;

            m_dataLength = l;
            m_dataBufferOffset = 0;

//cout << "Expecting " << m_dataLength << " bytes" << endl;

// avoid allocation of length 0
            if (l == 0)
                l = 1;

// We don't yet know if it's an RTP or RTCP packet, so we'll stick to RTP
            m_pDataBuffer = new uint8_t[l];
            if (m_pDataBuffer == 0)
                return ERR_RTP_OUTOFMEM;
        }
    }

    if (m_lengthBufferOffset == numLengthBuffer && m_pDataBuffer) // the last one is to make sure we didn't run out of memory
    {
        if (m_dataBufferOffset < m_dataLength)
        {
            int num = m_dataLength - m_dataBufferOffset;
            if (num > availLen)
                num = availLen;

            int r = 0;
            if (num > 0)
            {
                r = (int) recv(sock, (char *) (m_pDataBuffer + m_dataBufferOffset), num, 0);
                if (r < 0)
                    return ERR_RTP_TCPTRANS_ERRORINRECV;
            }

            m_dataBufferOffset += r;
            availLen -= r;
        }

        if (m_dataBufferOffset == m_dataLength)
            complete = true;
    }
    return 0;
}

} // end namespace