/**
 * vim: set ts=4 :
 * =============================================================================
 * SourceMod Sample Extension
 * Copyright (C) 2004-2008 AlliedModders LLC.  All rights reserved.
 * =============================================================================
 *
 * This program is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License, version 3.0, as published by the
 * Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License along with
 * this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * As a special exception, AlliedModders LLC gives you permission to link the
 * code of this program (as well as its derivative works) to "Half-Life 2," the
 * "Source Engine," the "SourcePawn JIT," and any Game MODs that run on software
 * by the Valve Corporation.  You must obey the GNU General Public License in
 * all respects for all other code used.  Additionally, AlliedModders LLC grants
 * this exception to all derivative works.  AlliedModders LLC defines further
 * exceptions, found in LICENSE.txt (as of this writing, version JULY-31-2007),
 * or <http://www.sourcemod.net/license.php>.
 *
 * Version: $Id$
 */
//#define _GNU_SOURCE
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/ioctl.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <fcntl.h>
#include <poll.h>
#include <opus.h>

#include <iclient.h>
#include <iserver.h>
#include <ISDKTools.h>

#include "inetmessage.h"

#include "CDetour/detours.h"
#include "extension.h"

// voice packets are sent over unreliable netchannel
//#define NET_MAX_DATAGRAM_PAYLOAD  4000    // = maximum unreliable payload size
// voice packetsize = 64 | netchannel overflows at >4000 bytes
// with 22050 samplerate and 512 frames per packet -> 23.22ms per packet
// SVC_VoiceData overhead = 5 bytes
// sensible limit of 8 packets per frame = 552 bytes -> 185.76ms of voice data per frame
//#define NET_MAX_VOICE_BYTES_FRAME (8 * (5 + 64))
#define NET_MAX_VOICE_BYTES_FRAME (10 * (5 + 64))

ConVar g_SmVoiceAddr("sm_voice_addr", "127.0.0.1", FCVAR_PROTECTED, "Voice server listen ip address.");
ConVar g_SmVoicePort("sm_voice_port", "27020", FCVAR_PROTECTED, "Voice server listen port.", true, 1025.0, true, 65535.0);

/**
 * @file extension.cpp
 * @brief Implement extension code here.
 */

template <typename T> inline T min_ext(T a, T b) { return a<b?a:b; }

const unsigned int CRCTable[256] = {
  0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
  0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
  0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2,
  0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
  0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9,
  0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
  0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c,
  0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
  0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423,
  0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
  0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106,
  0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
  0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d,
  0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
  0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
  0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
  0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7,
  0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
  0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa,
  0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
  0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81,
  0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
  0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84,
  0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
  0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
  0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
  0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e,
  0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
  0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55,
  0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
  0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28,
  0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
  0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f,
  0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
  0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
  0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
  0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69,
  0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
  0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc,
  0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
  0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693,
  0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
  0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d};


unsigned int UTIL_CRC32(const void *pdata, size_t data_length)
{
    unsigned char *data = (unsigned char *)pdata;
    unsigned int crc = 0xFFFFFFFF;
    unsigned char c;

    for(size_t i = 0; i < data_length; i++, data++)
    {
        c = (unsigned char)((crc ^ *data) & 0xFF);
        crc = CRCTable[c] ^ (crc >> 8);
    }

    return ~crc;
}

CVoice g_Interface;
SMEXT_LINK(&g_Interface);

CGlobalVars *gpGlobals = NULL;
ISDKTools *g_pSDKTools = NULL;
IServer *iserver = NULL;

double g_fLastVoiceData[SM_MAXPLAYERS + 1];
int g_aFrameVoiceBytes[SM_MAXPLAYERS + 1];
bool g_bIsNoSteam[SM_MAXPLAYERS + 1];
bool g_bClientMuted[SM_MAXPLAYERS + 1][SM_MAXPLAYERS + 1]; // [muter][mutee]

static void SendVoiceDataMsg(int fromClientSlot, IClient *pToClient, unsigned char *data, int nBytes, int64 xuid)
{
    SVC_VoiceData msg;
    msg.m_bProximity = false;
    msg.m_nLength    = nBytes * 8; // length in bits
    msg.m_xuid       = xuid;
    msg.m_nFromClient = fromClientSlot;
    msg.m_DataOut    = data;
    pToClient->SendNetMsg(msg);
}

#define Bits2Bytes(b) ((b+7)>>3)

/*
objdump -d /home/gameservers/css_dev/bin/engine_srv.so | grep -A 10 "_ZNK11CBaseClient13GetPlayerSlotEv"
00081a90 <_ZNK11CBaseClient13GetPlayerSlotEv>:
   81a90:       55                      push   %ebp
   81a91:       89 e5                   mov    %esp,%ebp
   81a93:       8b 45 08                mov    0x8(%ebp),%eax
   81a96:       5d                      pop    %ebp
   81a97:       8b 40 0c                mov    0xc(%eax),%eax
   81a9a:       c3                      ret
   81a9b:       8d 74 26 00             lea    0x0(%esi,%eiz,1),%esi
   81a9f:       90                      nop

00081aa0 <_ZThn4_NK11CBaseClient13GetPlayerSlotEv>:

mov 0xc(%eax),%eax -> offset is 12 bytes (0x0c)
*/

DETOUR_DECL_MEMBER1(ProcessVoiceData, bool, void *, msg)
{
    //in member class we use "this" to obtain the client.
    int playerSlot = *(int*)((char*)this + 12); //m_nClientSlot member CBaseClient which CGameClient inherits from. 
    int clientIndex = playerSlot + 1;
    
    CLC_VoiceData *voiceMsg = (CLC_VoiceData *)msg;

    char voiceDataBuffer[4096];
    int bitsRead = voiceMsg->m_DataIn.ReadBitsClamped(voiceDataBuffer, voiceMsg->m_nLength);
    int nBytes = Bits2Bytes(bitsRead);

    //still need this super important check for preventing empty voice packets spam.
    if (nBytes < 1)
        return true;

    if (clientIndex < 1 || clientIndex > SM_MAXPLAYERS)
        return true;
    
    // Reject voice packet if we'd send more than NET_MAX_VOICE_BYTES_FRAME voice bytes from this client in the current frame.
    // 5 = SVC_VoiceData header/overhead
    g_aFrameVoiceBytes[clientIndex] += 5 + nBytes;
    if (g_aFrameVoiceBytes[clientIndex] > NET_MAX_VOICE_BYTES_FRAME)
        return true;

    // Get IClient for sending
    IClient *pClient = iserver->GetClient(playerSlot);
    if (!pClient)
        return true;

    // Detect NoSteam 
    if (g_bIsNoSteam[clientIndex])
    {
        //convert nosteam CELT packet to OPUS for steam clients
        g_Interface.TranscodeNoSteamToSteam(playerSlot, nBytes, voiceDataBuffer);
        //send nosteam CELT packet to no steam clients
        int maxClients = iserver->GetClientCount();
        for (int i = 0; i < maxClients; i++)
        {
            IClient *pToClient = iserver->GetClient(i);
            if (!pToClient || !pToClient->IsConnected() || !pToClient->IsActive() || pToClient->IsFakeClient())
                continue;

            bool bSelf = (i == playerSlot);

            if (bSelf)
                continue;

            if (!g_bIsNoSteam[i + 1])
                continue;
            if (g_bClientMuted[i + 1][clientIndex])
                continue;
            //smutils->LogMessage(myself, "in ProcessVoiceData before SendVoiceDataMsg");
            SendVoiceDataMsg(playerSlot, pToClient, (unsigned char *)voiceDataBuffer, nBytes, voiceMsg->m_xuid);
        }
    }
    else
    {
        //convert steam OPUS packet to CELT for no steam clients
        g_Interface.PushPlayerVoiceData(playerSlot, nBytes, voiceDataBuffer);
        // Send steam Opus packet to Steam clients
        int maxClients = iserver->GetClientCount();
        for (int i = 0; i < maxClients; i++)
        {
            IClient *pToClient = iserver->GetClient(i);
            if (!pToClient || !pToClient->IsConnected() || !pToClient->IsActive() || pToClient->IsFakeClient())
                continue;

            bool bSelf = (i == playerSlot);

            if (bSelf)
                continue;
            if (g_bIsNoSteam[i + 1])
                continue;
            if (g_bClientMuted[i + 1][clientIndex])
                continue;
            //smutils->LogMessage(myself, "in ProcessVoiceData before SendVoiceDataMsg");
            SendVoiceDataMsg(playerSlot, pToClient, (unsigned char *)voiceDataBuffer, nBytes, voiceMsg->m_xuid);
        }
    }
    return true;
}

DETOUR_DECL_STATIC4(SV_BroadcastVoiceData, void, IClient *, pClient, int, nBytes, char *, data, int64, xuid)
{
}

double getTime()
{
    struct timespec tv;
    if(clock_gettime(CLOCK_REALTIME, &tv) != 0)
        return 0;

    return (tv.tv_sec + (tv.tv_nsec / 1000000000.0));
}

void OnGameFrame(bool simulating)
{
    g_Interface.OnGameFrame(simulating);
}

CVoice::CVoice()
{
    m_ListenSocket = -1;

    m_PollFds = 0;
    for(int i = 1; i < 1 + MAX_CLIENTS; i++)
        m_aPollFds[i].fd = -1;

    for(int i = 0; i < MAX_CLIENTS; i++)
        m_aClients[i].m_Socket = -1;

    m_OpusEncoder = NULL;
    m_AvailableTime = 0.0;

    m_VoiceDetour = NULL;
    m_ProcessVoiceDataDetour = NULL;
    m_SV_BroadcastVoiceData = NULL;

    m_TorchlightOpusDecoder = NULL;
    for (int i = 0; i <= SM_MAXPLAYERS; i++)
    {
        m_PlayerOpusDecoder[i] = NULL;
    }

    for (int i = 0; i <= SM_MAXPLAYERS; i++)
    {
        m_pCeltDecoder[i] = NULL;
    }

    m_pCeltMode             = NULL;
    m_pCeltCodec            = NULL;
    m_pCeltModePlayer  = NULL;
    m_torchMonoAccumLen     = 0;
    m_torchResampleAccum    = 0;
    memset(m_torchMonoAccum,  0, sizeof(m_torchMonoAccum));
    memset(m_nosteamSeqNum, 0, sizeof(m_nosteamSeqNum));

    memset(g_bIsNoSteam, 0, sizeof(g_bIsNoSteam));

    memset(m_playerAvailableTime, 0, sizeof(m_playerAvailableTime));
    for (int i = 0; i <= SM_MAXPLAYERS; i++)
        m_pCeltCodecPlayer[i] = NULL;

    memset(g_bClientMuted, 0, sizeof(g_bClientMuted));
    memset(m_nosteamResampleAccum, 0, sizeof(m_nosteamResampleAccum));
    memset(m_nosteamAvailableTime, 0, sizeof(m_nosteamAvailableTime));
    for (int i = 0; i <= SM_MAXPLAYERS; i++)
        m_nosteamOpusEncoder[i] = NULL;
}

bool CVoice::SDK_OnLoad(char *error, size_t maxlength, bool late)
{
    // Setup engine-specific data.
    Dl_info info;
    void *engineFactory = (void *)g_SMAPI->GetEngineFactory(false);
    if(dladdr(engineFactory, &info) == 0)
    {
        g_SMAPI->Format(error, maxlength, "dladdr(engineFactory) failed.");
        return false;
    }

    void *pEngineSo = dlopen(info.dli_fname, RTLD_NOW);
    if(pEngineSo == NULL)
    {
        g_SMAPI->Format(error, maxlength, "dlopen(%s) failed.", info.dli_fname);
        return false;
    }

    int engineVersion = g_SMAPI->GetSourceEngineBuild();
    void *adrVoiceData = NULL;

    switch (engineVersion)
    {
        case SOURCE_ENGINE_CSGO:
#ifdef _WIN32
            adrVoiceData = memutils->FindPattern(pEngineSo, "\x55\x8B\xEC\x81\xEC\xD0\x00\x00\x00\x53\x56\x57", 12);
#else
            adrVoiceData = memutils->ResolveSymbol(pEngineSo, "_Z21SV_BroadcastVoiceDataP7IClientiPcx");
#endif
            break;

        case SOURCE_ENGINE_LEFT4DEAD2:
#ifdef _WIN32
            adrVoiceData = memutils->FindPattern(pEngineSo, "\x55\x8B\xEC\x83\xEC\x70\xA1\x2A\x2A\x2A\x2A\x33\xC5\x89\x45\xFC\xA1\x2A\x2A\x2A\x2A\x53\x56", 23);
#else
            adrVoiceData = memutils->ResolveSymbol(pEngineSo, "_Z21SV_BroadcastVoiceDataP7IClientiPcx");
#endif
            break;

        case SOURCE_ENGINE_NUCLEARDAWN:
#ifdef _WIN32
            adrVoiceData = memutils->FindPattern(pEngineSo, "\x55\x8B\xEC\xA1\x2A\x2A\x2A\x2A\x83\xEC\x58\x57\x33\xFF", 14);
#else
            adrVoiceData = memutils->ResolveSymbol(pEngineSo, "_Z21SV_BroadcastVoiceDataP7IClientiPcx");
#endif
            break;

        case SOURCE_ENGINE_INSURGENCY:
#ifdef _WIN32
            adrVoiceData = memutils->FindPattern(pEngineSo, "\x55\x8B\xEC\x83\xEC\x74\x68\x2A\x2A\x2A\x2A\x8D\x4D\xE4\xE8", 15);
#else
            adrVoiceData = memutils->ResolveSymbol(pEngineSo, "_Z21SV_BroadcastVoiceDataP7IClientiPcx");
#endif
            break;

        case SOURCE_ENGINE_TF2:
        case SOURCE_ENGINE_CSS:
        case SOURCE_ENGINE_HL2DM:
        case SOURCE_ENGINE_DODS:
        case SOURCE_ENGINE_SDK2013:
#ifdef _WIN32
            adrVoiceData = memutils->FindPattern(pEngineSo, "\x55\x8B\xEC\xA1\x2A\x2A\x2A\x2A\x83\xEC\x50\x83\x78\x30", 14);
#else
            adrVoiceData = memutils->ResolveSymbol(pEngineSo, "_Z21SV_BroadcastVoiceDataP7IClientiPcx");
#endif
            break;

        default:
            g_SMAPI->Format(error, maxlength, "Unsupported game.");
            dlclose(pEngineSo);
            return false;
    }
    //2026 signature of CGameClient::ProcessVoiceData
    void *adrProcessVoiceData = memutils->ResolveSymbol(pEngineSo, "_ZN11CGameClient16ProcessVoiceDataEP13CLC_VoiceData");
    dlclose(pEngineSo);

    m_SV_BroadcastVoiceData = (t_SV_BroadcastVoiceData)adrVoiceData;
    if(!m_SV_BroadcastVoiceData)
    {
        g_SMAPI->Format(error, maxlength, "SV_BroadcastVoiceData sigscan failed.");
        return false;
    }

    // Setup voice detour.
    CDetourManager::Init(g_pSM->GetScriptingEngine(), NULL);

    m_VoiceDetour = DETOUR_CREATE_STATIC(SV_BroadcastVoiceData, adrVoiceData);

    if (!m_VoiceDetour)
    {
        g_SMAPI->Format(error, maxlength, "SV_BroadcastVoiceData detour failed.");
        return false;
    }

    m_VoiceDetour->EnableDetour();

    //2026 detouring CGameClient::ProcessVoiceData
    m_ProcessVoiceDataDetour = DETOUR_CREATE_MEMBER(ProcessVoiceData, adrProcessVoiceData);
    if (!m_ProcessVoiceDataDetour)
    {
        g_SMAPI->Format(error, maxlength, "ProcessVoiceData detour failed.");
        return false;
    }
    m_ProcessVoiceDataDetour->EnableDetour();

    //opus edit
    int err;
    m_OpusEncoder = opus_encoder_create(48000, 2, OPUS_APPLICATION_AUDIO, &err);
    if (err<0)
    {
        smutils->LogError(myself, "failed to create encode: %s", opus_strerror(err));
        return false;
    }

    opus_encoder_ctl(m_OpusEncoder, OPUS_SET_BITRATE(128000)); 
    opus_encoder_ctl(m_OpusEncoder, OPUS_SET_BANDWIDTH(OPUS_BANDWIDTH_FULLBAND));
    opus_encoder_ctl(m_OpusEncoder, OPUS_SET_SIGNAL(OPUS_SIGNAL_MUSIC)); //MDCT mode
    opus_encoder_ctl(m_OpusEncoder, OPUS_SET_LSB_DEPTH(16)); 
    opus_encoder_ctl(m_OpusEncoder, OPUS_SET_PACKET_LOSS_PERC(0));
    opus_encoder_ctl(m_OpusEncoder, OPUS_SET_FORCE_CHANNELS(2));

    if (err<0)
    {
        smutils->LogError(myself, "failed to set bitrate: %s\n", opus_strerror(err));
        return false;
    }

    // Opus decoder for torchlight (48000 Hz stereo)
    int err2;
    m_TorchlightOpusDecoder = opus_decoder_create(48000, 2, &err2);
    if (err2 < 0)
    {
        smutils->LogError(myself, "failed to create torchlight opus decoder: %s", opus_strerror(err2));
        return false;
    }

    // CELT encoder (22050 Hz mono, 512 samples/frame, 64 byte packets)
    m_CeltEncoderSettings.SampleRate_Hz      = 22050;
    //m_CeltEncoderSettings.TargetBitRate_Kbps = 64;
    m_CeltEncoderSettings.TargetBitRate_Kbps = 48;
    m_CeltEncoderSettings.FrameSize          = 512;
    m_CeltEncoderSettings.PacketSize         = 64;
    m_CeltEncoderSettings.Complexity         = 10;
    m_CeltEncoderSettings.FrameTime          = (double)m_CeltEncoderSettings.FrameSize / (double)m_CeltEncoderSettings.SampleRate_Hz;

    int theError;
    //torchlight celt
    m_pCeltMode = celt_mode_create(m_CeltEncoderSettings.SampleRate_Hz,
                                   m_CeltEncoderSettings.FrameSize, &theError);
    if (!m_pCeltMode)
    {
        g_SMAPI->Format(error, maxlength, "celt_mode_create error: %d", theError);
        SDK_OnUnload();
        return false;
    }

    m_pCeltCodec = celt_encoder_create_custom(m_pCeltMode, 1, &theError);
    if (!m_pCeltCodec)
    {
        g_SMAPI->Format(error, maxlength, "celt_encoder_create_custom error: %d", theError);
        SDK_OnUnload();
        return false;
    }

    celt_encoder_ctl(m_pCeltCodec, CELT_RESET_STATE_REQUEST, NULL);
    celt_encoder_ctl(m_pCeltCodec, CELT_SET_BITRATE(m_CeltEncoderSettings.TargetBitRate_Kbps * 1000));
    celt_encoder_ctl(m_pCeltCodec, CELT_SET_COMPLEXITY(m_CeltEncoderSettings.Complexity));

    //Player celt 
    m_pCeltModePlayer = celt_mode_create(m_CeltEncoderSettings.SampleRate_Hz,
                                     m_CeltEncoderSettings.FrameSize, &theError);
    if (!m_pCeltModePlayer)
    {
        g_SMAPI->Format(error, maxlength, "celt_mode_create 2 error: %d", theError);
        SDK_OnUnload();
        return false;
    }
    return true;
}

bool CVoice::SDK_OnMetamodLoad(ISmmAPI *ismm, char *error, size_t maxlen, bool late)
{
    GET_V_IFACE_CURRENT(GetEngineFactory, g_pCVar, ICvar, CVAR_INTERFACE_VERSION);
    gpGlobals = ismm->GetCGlobals();
    ConVar_Register(0, this);

    return true;
}

bool CVoice::RegisterConCommandBase(ConCommandBase *pVar)
{
    /* Always call META_REGCVAR instead of going through the engine. */
    return META_REGCVAR(pVar);
}

cell_t IsClientTalking(IPluginContext *pContext, const cell_t *params)
{
    int client = params[1];

    if(client < 1 || client > SM_MAXPLAYERS)
    {
        return pContext->ThrowNativeError("Client index %d is invalid", client);
    }

    double d = gpGlobals->curtime - g_fLastVoiceData[client];

    if(d < 0) // mapchange
        return false;

    if(d > 0.33)
        return false;

    return true;
}

cell_t Native_SetClientNoSteam(IPluginContext *pContext, const cell_t *params)
{
    int client = params[1];
    bool IsSteam = params[2];

    if (client < 1 || client > SM_MAXPLAYERS)
        return pContext->ThrowNativeError("Invalid client index %d", client);

    g_bIsNoSteam[client] = IsSteam;
    return 1;
}

cell_t Native_SendCeltVoiceInit(IPluginContext *pContext, const cell_t *params)
{
    int client = params[1];
    if (client < 1 || client > SM_MAXPLAYERS)
        return pContext->ThrowNativeError("Invalid client index %d", client);

    IClient *pClient = iserver->GetClient(client - 1);
    if (!pClient || !pClient->IsConnected())
        return 0;

    SVC_VoiceInit msg("vaudio_celt", 22050);
    pClient->SendNetMsg(msg);
    //smutils->LogMessage(myself, "Sent SVC_VoiceInit vaudio_celt to client %d", client);
    return 1;
}

cell_t Native_ClientMutedOtherClient(IPluginContext *pContext, const cell_t *params)
{
    int clientmuter = params[1];
    int clientmutee = params[2];
    if (clientmuter < 1 || clientmuter > SM_MAXPLAYERS)
        return pContext->ThrowNativeError("Invalid clientmuter index %d", clientmuter);

    if (clientmutee < 0 || clientmutee > SM_MAXPLAYERS) //we allow muting the SourceTV
        return pContext->ThrowNativeError("Invalid clientmutee index %d", clientmutee);

    g_bClientMuted[clientmuter][clientmutee] = params[3]; //true or false
    //smutils->LogMessage(myself, "native g_bClientMuted: %i. clientmuter: %i. clientmutee: %i", g_bClientMuted[clientmuter][clientmutee], clientmuter, clientmutee);
    return 1;
}
const sp_nativeinfo_t MyNatives[] =
{
    { "IsClientTalking", IsClientTalking },
    { "SetClientNoSteam",   Native_SetClientNoSteam },
    { "SendCeltVoiceInit", Native_SendCeltVoiceInit },
    { "ClientMutedOtherClient", Native_ClientMutedOtherClient },
    { NULL, NULL }
};

static void ListenSocketAction(void *pData)
{
    CVoice *pThis = (CVoice *)pData;
    pThis->ListenSocket();
}

void CVoice::SDK_OnAllLoaded()
{
    sharesys->AddNatives(myself, MyNatives);
    sharesys->RegisterLibrary(myself, "Voice");

    SM_GET_LATE_IFACE(SDKTOOLS, g_pSDKTools);
    if(g_pSDKTools == NULL)
    {
        smutils->LogError(myself, "SDKTools interface not found");
        SDK_OnUnload();
        return;
    }

    iserver = g_pSDKTools->GetIServer();
    if(iserver == NULL)
    {
        smutils->LogError(myself, "Failed to get IServer interface from SDKTools!");
        SDK_OnUnload();
        return;
    }

    // Init tcp server
    m_ListenSocket = socket(AF_INET, SOCK_STREAM, 0);
    if(m_ListenSocket < 0)
    {
        smutils->LogError(myself, "Failed creating socket.");
        SDK_OnUnload();
        return;
    }

    int yes = 1;
    if(setsockopt(m_ListenSocket, SOL_SOCKET, SO_REUSEADDR, &yes, sizeof(int)) < 0)
    {
        smutils->LogError(myself, "Failed setting SO_REUSEADDR on socket.");
        SDK_OnUnload();
        return;
    }

    // This doesn't seem to work right away ...
    engine->ServerCommand("exec sourcemod/extension.Voice.cfg\n");
    engine->ServerExecute();

    // ... delay starting listen server to next frame
    smutils->AddFrameAction(ListenSocketAction, this);
}

void CVoice::ListenSocket()
{
    if(m_PollFds > 0)
        return;

    sockaddr_in bindAddr;
    memset(&bindAddr, 0, sizeof(bindAddr));
    bindAddr.sin_family = AF_INET;
    inet_aton(g_SmVoiceAddr.GetString(), &bindAddr.sin_addr);
    bindAddr.sin_port = htons(g_SmVoicePort.GetInt());

    smutils->LogMessage(myself, "Binding to %s:%d!\n", g_SmVoiceAddr.GetString(), g_SmVoicePort.GetInt());

    if(bind(m_ListenSocket, (sockaddr *)&bindAddr, sizeof(sockaddr_in)) < 0)
    {
        smutils->LogError(myself, "Failed binding to socket (%d '%s').", errno, strerror(errno));
        SDK_OnUnload();
        return;
    }

    if(listen(m_ListenSocket, MAX_CLIENTS) < 0)
    {
        smutils->LogError(myself, "Failed listening on socket.");
        SDK_OnUnload();
        return;
    }

    m_aPollFds[0].fd = m_ListenSocket;
    m_aPollFds[0].events = POLLIN;
    m_PollFds++;

    smutils->AddGameFrameHook(::OnGameFrame);
}

void CVoice::SDK_OnUnload()
{
    smutils->RemoveGameFrameHook(::OnGameFrame);

    if(m_VoiceDetour)
    {
        m_VoiceDetour->Destroy();
        m_VoiceDetour = NULL;
    }

    if (m_ProcessVoiceDataDetour)
    {
        m_ProcessVoiceDataDetour->Destroy();
        m_ProcessVoiceDataDetour = NULL;
    }

    if(m_ListenSocket != -1)
    {
        close(m_ListenSocket);
        m_ListenSocket = -1;
    }

    for(int Client = 0; Client < MAX_CLIENTS; Client++)
    {
        if(m_aClients[Client].m_Socket != -1)
        {
            close(m_aClients[Client].m_Socket);
            m_aClients[Client].m_Socket = -1;
        }
    }

    opus_encoder_destroy(m_OpusEncoder);

    if (m_TorchlightOpusDecoder)
    {
        opus_decoder_destroy(m_TorchlightOpusDecoder);
        m_TorchlightOpusDecoder = NULL;
    }

    for (int i = 0; i <= SM_MAXPLAYERS; i++)
    {
        if (m_PlayerOpusDecoder[i])
        {
            opus_decoder_destroy(m_PlayerOpusDecoder[i]);
            m_PlayerOpusDecoder[i] = NULL;
        }
    }

    if (m_pCeltCodec)
    {
        celt_encoder_destroy(m_pCeltCodec);
        m_pCeltCodec = NULL;
    }

    if (m_pCeltMode)
    {
        celt_mode_destroy(m_pCeltMode);
        m_pCeltMode = NULL;
    }

    for (int i = 0; i <= SM_MAXPLAYERS; i++)
    {
        if (m_pCeltCodecPlayer[i])
        {
            celt_encoder_destroy(m_pCeltCodecPlayer[i]);
            m_pCeltCodecPlayer[i] = NULL;
        }
    }

    if (m_pCeltModePlayer)
    {
        celt_mode_destroy(m_pCeltModePlayer);
        m_pCeltModePlayer = NULL;
    }

    for (int i = 0; i <= SM_MAXPLAYERS; i++)
    {
        if (m_pCeltDecoder[i])
        {
            celt_decoder_destroy(m_pCeltDecoder[i]);
            m_pCeltDecoder[i] = NULL;
        }
    }

    for (int i = 0; i <= SM_MAXPLAYERS; i++)
    {
        if (m_nosteamOpusEncoder[i])
        {
            opus_encoder_destroy(m_nosteamOpusEncoder[i]);
            m_nosteamOpusEncoder[i] = NULL;
        }
    }
}

void CVoice::OnGameFrame(bool simulating)
{
    HandleNetwork();
    HandleVoiceData(); //torchlight audio emitting
    HandleNoSteamVoiceData(); //send opus packets to steamers.

    //send celt packets to nosteamers
    int maxClients = iserver->GetClientCount();
    for (int i = 0; i < maxClients; i++)
    {
        if (!m_pCeltCodecPlayer[i])
            continue;

        // Keep draining 512-sample blocks until the buffer has less than one full frame remaining
        while (m_playerVoiceBuffer[i].TotalLength() >= m_CeltEncoderSettings.FrameSize)
        {
            HandlePlayerVoiceData(i);
        }
    }

    // Reset per-client voice byte counter to 0 every frame.
    memset(g_aFrameVoiceBytes, 0, sizeof(g_aFrameVoiceBytes));
}

void CVoice::HandleNetwork()
{
    if(m_ListenSocket == -1)
        return;

    int PollRes = poll(m_aPollFds, m_PollFds, 0);
    if(PollRes <= 0)
        return;

    // Accept new clients
    if(m_aPollFds[0].revents & POLLIN)
    {
        // Find slot
        int Client;
        for(Client = 0; Client < MAX_CLIENTS; Client++)
        {
            if(m_aClients[Client].m_Socket == -1)
                break;
        }

        // no free slot
        if(Client != MAX_CLIENTS)
        {
            sockaddr_in addr;
            socklen_t size = sizeof(sockaddr_in);
            int Socket = accept(m_ListenSocket, (sockaddr *)&addr, &size);

            m_aClients[Client].m_Socket = Socket;
            m_aClients[Client].m_BufferWriteIndex = 0;
            m_aClients[Client].m_LastLength = 0;
            m_aClients[Client].m_LastValidData = 0.0;
            m_aClients[Client].m_New = true;
            m_aClients[Client].m_UnEven = false;

            m_aPollFds[m_PollFds].fd = Socket;
            m_aPollFds[m_PollFds].events = POLLIN | POLLHUP;
            m_aPollFds[m_PollFds].revents = 0;
            m_PollFds++;

            //smutils->LogMessage(myself, "Client %d connected!\n", Client);
        }
    }

    bool CompressPollFds = false;
    for(int PollFds = 1; PollFds < m_PollFds; PollFds++)
    {
        int Client = -1;
        for(Client = 0; Client < MAX_CLIENTS; Client++)
        {
            if(m_aClients[Client].m_Socket == m_aPollFds[PollFds].fd)
                break;
        }
        if(Client == -1)
            continue;

        CClient *pClient = &m_aClients[Client];

        // Connection shutdown prematurely ^C
        // Make sure to set SO_LINGER l_onoff = 1, l_linger = 0
        if(m_aPollFds[PollFds].revents & POLLHUP)
        {
            close(pClient->m_Socket);
            pClient->m_Socket = -1;
            m_aPollFds[PollFds].fd = -1;
            CompressPollFds = true;
            //smutils->LogMessage(myself, "Client %d disconnected!(2)\n", Client);
            continue;
        }

        // Data available?
        if(!(m_aPollFds[PollFds].revents & POLLIN))
            continue;

        size_t BytesAvailable;
        if(ioctl(pClient->m_Socket, FIONREAD, &BytesAvailable) == -1)
            continue;

        if(pClient->m_New)
        {
            pClient->m_BufferWriteIndex = m_Buffer.GetReadIndex();
            pClient->m_New = false;
        }

        m_Buffer.SetWriteIndex(pClient->m_BufferWriteIndex);

        // Don't recv() when we can't fit data into the ringbuffer
        unsigned char aBuf[32768];
        if(min_ext(BytesAvailable, sizeof(aBuf)) > m_Buffer.CurrentFree() * sizeof(int16_t))
            continue;

        // Edge case: previously received data is uneven and last recv'd byte has to be prepended
        int Shift = 0;
        if(pClient->m_UnEven)
        {
            Shift = 1;
            aBuf[0] = pClient->m_Remainder;
            pClient->m_UnEven = false;
        }

        ssize_t Bytes = recv(pClient->m_Socket, &aBuf[Shift], sizeof(aBuf) - Shift, 0);

        if(Bytes <= 0)
        {
            close(pClient->m_Socket);
            pClient->m_Socket = -1;
            m_aPollFds[PollFds].fd = -1;
            CompressPollFds = true;
            //smutils->LogMessage(myself, "Client %d disconnected!(1)\n", Client);
            continue;
        }

        Bytes += Shift;

        // Edge case: data received is uneven (can't be divided by two)
        // store last byte, drop it here and prepend it right before the next recv
        if(Bytes & 1)
        {
            pClient->m_UnEven = true;
            pClient->m_Remainder = aBuf[Bytes - 1];
            Bytes -= 1;
        }

        // Got data!
        OnDataReceived(pClient, (int16_t *)aBuf, Bytes / sizeof(int16_t));

        pClient->m_LastLength = m_Buffer.CurrentLength();
        pClient->m_BufferWriteIndex = m_Buffer.GetWriteIndex();
    }

    if(CompressPollFds)
    {
        for(int PollFds = 1; PollFds < m_PollFds; PollFds++)
        {
            if(m_aPollFds[PollFds].fd != -1)
                continue;

            for(int PollFds_ = PollFds; PollFds_ < 1 + MAX_CLIENTS; PollFds_++)
                m_aPollFds[PollFds_].fd = m_aPollFds[PollFds_ + 1].fd;

            PollFds--;
            m_PollFds--;
        }
    }
}

void CVoice::OnDataReceived(CClient *pClient, int16_t *pData, size_t Samples)
{
    // Check for empty input
    ssize_t DataStartsAt = -1;
    for(size_t i = 0; i < Samples; i++)
    {
        if(pData[i] == 0)
            continue;

        DataStartsAt = i;
        break;
    }

    // Discard empty data if last vaild data was more than a second ago.
    if(pClient->m_LastValidData + 1.0 < getTime())
    {
        // All empty
        if(DataStartsAt == -1)
            return;

        // Data starts here
        pData += DataStartsAt;
        Samples -= DataStartsAt;
    }

    if(!m_Buffer.PushTorch(pData, Samples))
    {
        smutils->LogError(myself, "Buffer push failed!!! Samples: %u, Free: %u\n", Samples, m_Buffer.CurrentFree());
        return;
    }

    pClient->m_LastValidData = getTime();
}


void CVoice::HandleVoiceData()
{
    uint32_t sampleRate = 48000;
    const int SamplesPerChannel = 480;
    const int Channels = 2;
    int TotalSamplesPerFrame = SamplesPerChannel * Channels;

    int FramesAvailable = m_Buffer.TotalLength() / TotalSamplesPerFrame;
    if(!FramesAvailable)
        return;

    //int FramesMax = 5;
    int FramesMax = 2; //used to be 5
    bool reset_state = false;
    if (FramesAvailable <= FramesMax)
    {
        reset_state = true;
    }
    FramesAvailable = min_ext(FramesAvailable, FramesMax);

    // Allow less buffering after audio has started playing
    if (m_Buffer.TotalLength() < TotalSamplesPerFrame)
        return;

    float TimeAvailable = (float)m_Buffer.TotalLength() / sampleRate;
    if (m_AvailableTime < getTime() && TimeAvailable < 0.2)
        return;

    double maxBuffer = (m_AvailableTime < getTime()) ? 0.2 : 0.04;
    if (m_AvailableTime > getTime() + maxBuffer)
        return;
    

    IClient *pClient = iserver->GetClient(0);
    if(!pClient)
        return;

    unsigned char aFinal[8192];
    size_t FinalSize = 0;

    // 1. Steam Account ID (4 bytes)
    uint32_t steamID = 1;
    memcpy(&aFinal[FinalSize], &steamID, sizeof(uint32_t));
    FinalSize += sizeof(uint32_t);

    // 2. Steam Community (4 bytes)
    uint32_t steamCommunity = 0x01100001;
    memcpy(&aFinal[FinalSize], &steamCommunity, sizeof(uint32_t));
    FinalSize += sizeof(uint32_t);

    // 3. Payload Type 11 (1 byte)
    aFinal[FinalSize++] = 0x0B;

    // 4. Sample Rate (2 bytes little-endian)
    memcpy(&aFinal[FinalSize], &sampleRate, sizeof(uint16_t));
    FinalSize += sizeof(uint16_t);

    // 5. Payload Type 5 for Opus. 6 for opus plc (1 byte)
    aFinal[FinalSize++] = 0x05;

    // 6. Reserve space for total data length (2 bytes little-endian)
    uint16_t *pTotalDataLength = (uint16_t*)&aFinal[FinalSize];
    FinalSize += sizeof(uint16_t);
    *pTotalDataLength = 0;

    // 7. Encode frames
    for(int Frame = 0; Frame < FramesAvailable; Frame++)
    {
        int16_t aBuffer[TotalSamplesPerFrame];

        size_t OldReadIdx = m_Buffer.m_ReadIndex;
		size_t OldCurLength = m_Buffer.CurrentLength();
		size_t OldTotalLength = m_Buffer.TotalLength();

        if(!m_Buffer.Pop(aBuffer, TotalSamplesPerFrame))
        {
            smutils->LogError(myself, "Buffer pop failed!");
            return;
        }

        uint16_t *pFrameSize = (uint16_t*)&aFinal[FinalSize];
        FinalSize += sizeof(uint16_t);
        *pFrameSize = sizeof(aFinal) - sizeof(uint32_t) - FinalSize;

        // Encode with Opus
        //pcm <tt>opus_int16*</tt>: Input signal (interleaved if 2 channels). length is frame_size*channels*sizeof(opus_int16)
        int nbBytes = opus_encode(m_OpusEncoder, (const opus_int16*)aBuffer, SamplesPerChannel,
                                  &aFinal[FinalSize], *pFrameSize);
        if (nbBytes <= 1)
        {
            smutils->LogError(myself, "Opus encode failed: %s", opus_strerror(nbBytes));
            return;
        }
        BroadcastVoiceDataTorchlightCelt(pClient, aBuffer, SamplesPerChannel);

        // Write frame size
        *pFrameSize = (uint16_t)nbBytes;
        *pTotalDataLength += sizeof(uint16_t) + nbBytes;
        FinalSize += nbBytes;

        // Check for buffer underruns
        for(int Client = 0; Client < MAX_CLIENTS; Client++)
        {
            CClient *pClient = &m_aClients[Client];
            if(pClient->m_Socket == -1 || pClient->m_New == true)
                continue;

            m_Buffer.SetWriteIndex(pClient->m_BufferWriteIndex);

            if(m_Buffer.CurrentLength() > pClient->m_LastLength)
            {
                pClient->m_BufferWriteIndex = m_Buffer.GetReadIndex();
                m_Buffer.SetWriteIndex(pClient->m_BufferWriteIndex);
                pClient->m_LastLength = m_Buffer.CurrentLength();
            }
        }
    }

    // 8. Add CRC32
    uint32_t crc32_value = UTIL_CRC32(aFinal, FinalSize);
    memcpy(&aFinal[FinalSize], &crc32_value, sizeof(uint32_t));
    FinalSize += sizeof(uint32_t);
    
    int maxClients = iserver->GetClientCount();
    for (int i = 0; i < maxClients; i++)
    {
        IClient *pToClient = iserver->GetClient(i);
        if (!pToClient || !pToClient->IsConnected() || !pToClient->IsActive() || pToClient->IsFakeClient())
            continue;
        if (g_bClientMuted[i + 1][pClient->GetPlayerSlot()])
            continue;
        if (!g_bIsNoSteam[i + 1])
        {
            //sending opus packets to steam users.
            SendVoiceDataMsg(pClient->GetPlayerSlot(), pToClient, aFinal, FinalSize, 0);
        }
    }

    if (m_AvailableTime < getTime())
        m_AvailableTime = getTime();
    m_AvailableTime += (double)FramesAvailable * 0.01;
    
    if (reset_state)
    {
        opus_encoder_ctl(m_OpusEncoder, OPUS_RESET_STATE);
    }
}

void CVoice::BroadcastVoiceDataTorchlightCelt(IClient *pClient, int16_t *pPCM, int nSamples)
{
    // pPCM is stereo interleaved at 48000 Hz (SamplesPerChannel * 2 total samples)
    // Downsample to mono 22050 Hz and accumulate into m_torchMonoAccum
    const int STEP = m_CeltEncoderSettings.SampleRate_Hz; // 22050
    const int DIV  = 48000;
    const int CELT_FRAME_SIZE  = m_CeltEncoderSettings.FrameSize;   // 512
    const int CELT_PACKET_SIZE = m_CeltEncoderSettings.PacketSize;  // 64

    int fromSlot = pClient->GetPlayerSlot();
    int maxClients = iserver->GetClientCount();

    for (int i = 0; i < nSamples; i++)
    {
        if (m_torchMonoAccumLen >= 4096)
            break;

        int32_t mono = ((int32_t)pPCM[i * 2] + (int32_t)pPCM[i * 2 + 1]) / 2;
        if (mono >  32767) mono =  32767;
        if (mono < -32768) mono = -32768;

        m_torchResampleAccum += STEP;
        while (m_torchResampleAccum >= DIV)
        {
            m_torchResampleAccum -= DIV;
            if (m_torchMonoAccumLen < 4096)
                m_torchMonoAccum[m_torchMonoAccumLen++] = (int16_t)mono;
        }
    }

    while (m_torchMonoAccumLen >= CELT_FRAME_SIZE)
    {
        unsigned char celtPacket[CELT_PACKET_SIZE];
        int celtBytes = celt_encode(m_pCeltCodec, m_torchMonoAccum, CELT_FRAME_SIZE,
                                    celtPacket, CELT_PACKET_SIZE);
        if (celtBytes > 0)
        {
            for (int i = 0; i < maxClients; i++)
            {
                IClient *pToClient = iserver->GetClient(i);
                if (!pToClient || !pToClient->IsConnected() || !pToClient->IsActive() || pToClient->IsFakeClient())
                    continue;
                if (!g_bIsNoSteam[i + 1]) //i dont actually understand why the index is one off here.
                    continue;
                if (g_bClientMuted[i + 1][fromSlot])
                    continue;
                //smutils->LogMessage(myself, "right before SendVoiceDataMsg");
                SendVoiceDataMsg(fromSlot, pToClient, celtPacket, celtBytes, 0);
            }
        }
        else
        {
            smutils->LogError(myself, "BroadcastVoiceDataTorchlightCelt: celt_encode failed: %d", celtBytes);
        }

        m_torchMonoAccumLen -= CELT_FRAME_SIZE;
        if (m_torchMonoAccumLen > 0)
            memmove(m_torchMonoAccum, m_torchMonoAccum + CELT_FRAME_SIZE,
                    m_torchMonoAccumLen * sizeof(int16_t));
    }
}

void CVoice::PushPlayerVoiceData(int playerSlot, int nBytes, char *data)
{
    if (playerSlot < 0 || playerSlot >= SM_MAXPLAYERS)
        return;

    if (!m_pCeltCodecPlayer[playerSlot])
    {
        int theError;
        m_pCeltCodecPlayer[playerSlot] = celt_encoder_create_custom(m_pCeltModePlayer, 1, &theError);
        if (!m_pCeltCodecPlayer[playerSlot])
        {
            smutils->LogError(myself, "PushPlayerVoiceData: celt_encoder_create_custom failed: %d", theError);
            return;
        }
        celt_encoder_ctl(m_pCeltCodecPlayer[playerSlot], CELT_RESET_STATE_REQUEST, NULL);
        celt_encoder_ctl(m_pCeltCodecPlayer[playerSlot], CELT_SET_BITRATE(m_CeltEncoderSettings.TargetBitRate_Kbps * 1000));
        celt_encoder_ctl(m_pCeltCodecPlayer[playerSlot], CELT_SET_COMPLEXITY(m_CeltEncoderSettings.Complexity));
    }

    if (!m_PlayerOpusDecoder[playerSlot])
    {
        int err;
        m_PlayerOpusDecoder[playerSlot] = opus_decoder_create(24000, 1, &err);
        if (err < 0)
        {
            smutils->LogError(myself, "PushPlayerVoiceData: opus_decoder_create failed: %s", opus_strerror(err));
            return;
        }
    }

    double now = (double)gpGlobals->curtime;
    double timeSinceLastVoice = now - g_fLastVoiceData[playerSlot + 1];
    if (timeSinceLastVoice > 0.5 && g_fLastVoiceData[playerSlot + 1] != 0.0)
    {
        celt_encoder_ctl(m_pCeltCodecPlayer[playerSlot], CELT_RESET_STATE_REQUEST, NULL);
        opus_decoder_ctl(m_PlayerOpusDecoder[playerSlot], OPUS_RESET_STATE);

        // Clear out any stale, partial remaining samples left over in the queue
        while(m_playerVoiceBuffer[playerSlot].TotalLength() > 0)
        {
            int16_t trash[512];
            size_t toPop = m_playerVoiceBuffer[playerSlot].TotalLength() > 512 ? 512 : m_playerVoiceBuffer[playerSlot].TotalLength();
            m_playerVoiceBuffer[playerSlot].Pop(trash, toPop);
        }

        //smutils->LogMessage(myself, "Voice states flushed cleanly. playerSlot: %d", playerSlot);
    }

    // Update the timestamp to mark this active packet's arrival
    g_fLastVoiceData[playerSlot + 1] = now;

    const unsigned char *p = (const unsigned char *)data;

    /*
    int dumpLen = nBytes < 24 ? nBytes : 24;
    char hexBuf[24 * 3 + 1];
    int pos = 0;
    for (int i = 0; i < dumpLen; i++)
    {
        static const char hex[] = "0123456789ABCDEF";
        hexBuf[pos++] = hex[(p[i] >> 4) & 0xF];
        hexBuf[pos++] = hex[p[i] & 0xF];
        hexBuf[pos++] = ' ';
    }
    hexBuf[pos] = '\0';
    smutils->LogMessage(myself, "[INBOUND STEAM] nBytes=%d, First bytes: %s", nBytes, hexBuf);
    */

    uint16_t totalDataLength;
    memcpy(&totalDataLength, p + 12, sizeof(uint16_t));
    if ((int)(14 + totalDataLength + 4) != nBytes)
        return;

    uint32_t expectedCRC;
    memcpy(&expectedCRC, p + nBytes - 4, sizeof(uint32_t));
    if (UTIL_CRC32(p, nBytes - 4) != expectedCRC)
        return;

    int offset = 14;
    int end    = 14 + (int)totalDataLength;

    if (offset + 4 <= end)
    {
        uint16_t trueAudioPayloadLen;
        memcpy(&trueAudioPayloadLen, p + 12, sizeof(uint16_t)); 

        // Frame 1 always starts exactly at offset 18
        int frame1Start = 18;
        if (frame1Start >= end) return;

        const unsigned char *frame1Ptr = p + frame1Start;
        
        // Find the start of Frame 2 by scanning for the next 0x68 TOC marker
        int frame2Start = -1;
        
        // A standard 24kHz Opus frame will practically never be shorter than 30 bytes
        for (int i = frame1Start + 30; i < end - 4; i++)
        {
            if (p[i] == 0x68) //TOC -> 0x68 
            {
                // Verify if this is the start of Frame 2
                frame2Start = i;
                break;
            }
        }

        int16_t pcmFrameBuffer[960];
        int totalDecodedSamples = 0;

        // Calculate explicit size for Frame 1
        int frame1Size = (frame2Start != -1) ? (frame2Start - frame1Start) : (end - frame1Start);

        if (frame1Size > 0)
        {
            //smutils->LogMessage(myself, "[VOICE-FIX] Frame 1 Determined Size: %d bytes. TOC: 0x%02X", frame1Size, frame1Ptr[0]);
            
            int samples1 = opus_decode(m_PlayerOpusDecoder[playerSlot],
                                       frame1Ptr, frame1Size,
                                       &pcmFrameBuffer[0], 480, 0);
            
            if (samples1 > 0) totalDecodedSamples += samples1;
        }

        // Process Frame 2 if a second TOC marker was identified
        if (frame2Start != -1)
        {
            const unsigned char *frame2Ptr = p + frame2Start;
            int frame2Size = end - frame2Start; // Frame 2 spans to the end of the payload buffer

            if (frame2Size > 0)
            {
                //smutils->LogMessage(myself, "[VOICE-FIX] Frame 2 Determined Size: %d bytes. TOC: 0x%02X", frame2Size, frame2Ptr[0]);
                
                int samples2 = opus_decode(m_PlayerOpusDecoder[playerSlot],
                                           frame2Ptr, frame2Size,
                                           &pcmFrameBuffer[totalDecodedSamples], 480, 0);
                
                if (samples2 > 0) totalDecodedSamples += samples2;
            }
        }

        int16_t resampledFrameBuffer[960];
        int totalResampledSamples = 0;

        if (totalDecodedSamples > 0)
        {
            // The exact conversion ratio factor is 147 / 160
            // 480 samples at 24kHz converts precisely into 441 samples at 22.05kHz
            // 960 samples (2 frames) converts precisely into 882 samples
            totalResampledSamples = (totalDecodedSamples * 147) / 160;

            for (int i = 0; i < totalResampledSamples; i++)
            {
                // Determine where this output sample lands on the input timeline
                double srcPosition = (double)i * 160.0 / 147.0;
                int srcIndex = (int)srcPosition;
                double fraction = srcPosition - (double)srcIndex;

                if (srcIndex + 1 < totalDecodedSamples)
                {
                    // Linear interpolate between the two closest matching input samples
                    int16_t sampleA = pcmFrameBuffer[srcIndex];
                    int16_t sampleB = pcmFrameBuffer[srcIndex + 1];
                    resampledFrameBuffer[i] = (int16_t)(sampleA + fraction * (sampleB - sampleA));
                }
                else
                {
                    // Handle boundary edge case for the final trailing sample
                    resampledFrameBuffer[i] = pcmFrameBuffer[srcIndex];
                }
            }
        }
        // --- PUSH SOUND TIMELINES SEQUENTIALLY ---
        if (totalResampledSamples > 0)
        {
            size_t freeSpace = m_playerVoiceBuffer[playerSlot].CurrentFree();
            if ((size_t)totalResampledSamples <= freeSpace)
            {
                // Push the perfectly timed 22050Hz stream to the CELT ring buffer
                m_playerVoiceBuffer[playerSlot].Push(resampledFrameBuffer, totalResampledSamples);
            }
        }
    }
}

void CVoice::HandlePlayerVoiceData(int playerSlot)
{
    const int CELT_FRAME_SIZE  = m_CeltEncoderSettings.FrameSize;  
    const int CELT_PACKET_SIZE = m_CeltEncoderSettings.PacketSize; 
    int maxClients = iserver->GetClientCount();

    if (!m_pCeltCodecPlayer[playerSlot])
        return;

    size_t currentBufferLength = m_playerVoiceBuffer[playerSlot].TotalLength();
    if (currentBufferLength < (size_t)CELT_FRAME_SIZE)
    {
        return; // Not enough data yet
    }

    // We have a solid block! Extract exactly one frame's worth of samples
    int16_t celtInput[512];
    if (!m_playerVoiceBuffer[playerSlot].Pop(celtInput, CELT_FRAME_SIZE))
    {
        return;
    }

    // Run the encoder pass on our clean block
    unsigned char celtPacket[64];
    int celtBytes = celt_encode(m_pCeltCodecPlayer[playerSlot], celtInput,
                                CELT_FRAME_SIZE, celtPacket, CELT_PACKET_SIZE);

    if (celtBytes > 0)
    {
        for (int i = 0; i < maxClients; i++)
        {
            IClient *pToClient = iserver->GetClient(i);
            if (!pToClient || !pToClient->IsConnected() || !pToClient->IsActive())
                continue;
            if (!g_bIsNoSteam[i + 1])
                continue;
            if (g_bClientMuted[i + 1][playerSlot + 1])
                continue;

            SendVoiceDataMsg(playerSlot, pToClient, celtPacket, celtBytes, 0);
        }
    }
    else
    {
        smutils->LogError(myself, "HandlePlayerVoiceData: celt_encode failed: %d", celtBytes);
    }
}

void CVoice::TranscodeNoSteamToSteam(int playerSlot, int nBytes, char *data)
{
    if (playerSlot < 0 || playerSlot >= SM_MAXPLAYERS)
        return;
    if (!m_pCeltDecoder[playerSlot])
    {
        int err;
        m_pCeltDecoder[playerSlot] = celt_decoder_create_custom(m_pCeltModePlayer, 1, &err);
        if (!m_pCeltDecoder[playerSlot])
        {
            smutils->LogError(myself, "TranscodeNoSteamToSteam: celt_decoder_create_custom failed: %d", err);
            return;
        }
    }

    if (!m_nosteamOpusEncoder[playerSlot])
    {
        int err;
        m_nosteamOpusEncoder[playerSlot] = opus_encoder_create(24000, 1, OPUS_APPLICATION_AUDIO, &err);
        if (err < 0)
        {
            smutils->LogError(myself, "TranscodeNoSteamToSteam: opus_encoder_create failed: %s", opus_strerror(err));
            return;
        }
        /*
            0x68 TOC -> 01101000 -> c bits (6-7): 00 -> s bit (5): 0 (Mono) -> config bits (0-4): 01101 (13)
            Mode: Hybrid (SILK + CELT)
            Bandwidth: SWB
            Frame Size: 20 ms
            BITRATE 640000 changes TOC to 0xD8
        */
        opus_encoder_ctl(m_nosteamOpusEncoder[playerSlot], OPUS_SET_BITRATE(32000));
        opus_encoder_ctl(m_nosteamOpusEncoder[playerSlot], OPUS_SET_SIGNAL(OPUS_SIGNAL_VOICE));
    }

    int16_t pcmBuf[512];
    int decoded = celt_decode(m_pCeltDecoder[playerSlot],
                              (const unsigned char *)data, nBytes,
                              pcmBuf, m_CeltEncoderSettings.FrameSize);
    if (decoded < 0)
    {
        smutils->LogError(myself, "TranscodeNoSteamToSteam: celt_decode failed: %d", decoded);
        return;
    }

    // Resample 22050 -> 24000 and push into ring buffer
    const int STEP = 24000;
    const int DIV  = 22050;

    for (int i = 0; i < decoded; i++)
    {
        m_nosteamResampleAccum[playerSlot] += STEP;
        while (m_nosteamResampleAccum[playerSlot] >= DIV)
        {
            m_nosteamResampleAccum[playerSlot] -= DIV;
            int16_t sample = pcmBuf[i];
            if (m_nosteamOpusPCMBuffer[playerSlot].CurrentFree() > 0)
                m_nosteamOpusPCMBuffer[playerSlot].Push(&sample, 1);
        }
    }
}

void CVoice::HandleNoSteamVoiceData()
{
    int maxClients = iserver->GetClientCount();

    for (int playerSlot = 0; playerSlot < maxClients; playerSlot++)
    {
        if (!m_nosteamOpusEncoder[playerSlot])
            continue;

        if (m_nosteamOpusPCMBuffer[playerSlot].TotalLength() < 480)
            continue;

        float timeAvailable = (float)m_nosteamOpusPCMBuffer[playerSlot].TotalLength() / 24000.0f;

        if (m_nosteamAvailableTime[playerSlot] < getTime() && timeAvailable < 0.1)
            continue;

        if (m_nosteamAvailableTime[playerSlot] > getTime() + 1.0)
            continue;

        int framesEmitted = 0;
        while (m_nosteamOpusPCMBuffer[playerSlot].TotalLength() >= 480)
        {
            if (framesEmitted >= 1)
                break;

            int16_t opusInput[480];
            if (!m_nosteamOpusPCMBuffer[playerSlot].Pop(opusInput, 480))
                break;

            unsigned char opusBuf[512];
            int opusBytes = opus_encode(m_nosteamOpusEncoder[playerSlot], opusInput, 480, opusBuf, sizeof(opusBuf));
            if (opusBytes < 0)
            {
                smutils->LogError(myself, "HandleNoSteamVoiceData: opus_encode failed: %s",
                                  opus_strerror(opusBytes));
                break;
            }

            IClient *pNoSteamClient = iserver->GetClient(playerSlot);
            if (!pNoSteamClient)
                continue;

            const char *networkID = pNoSteamClient->GetNetworkIDString();
            uint32_t accountID = 0;
            // Parse [U:1:XXXXXXXX] format
            const char *numStart = strrchr(networkID, ':');
            if (numStart)
                accountID = (uint32_t)atoi(numStart + 1);

            // Build modern Steam voice packet with working routing blocks
            unsigned char aFinal[8192];
            size_t FinalSize = 0;

            // Build Steam voice packet header
            uint32_t steamID = accountID;
            uint32_t steamCommunity = 0x01100001;
            memcpy(&aFinal[FinalSize], &steamID, sizeof(uint32_t));
            FinalSize += sizeof(uint32_t);
            memcpy(&aFinal[FinalSize], &steamCommunity, sizeof(uint32_t));
            FinalSize += sizeof(uint32_t);

            // 2. Payload Type (1 byte)
            aFinal[FinalSize++] = 0x0B;

            // 3. Sample Rate (2 bytes little-endian)
            uint16_t sampleRate = 24000;
            memcpy(&aFinal[FinalSize], &sampleRate, sizeof(uint16_t));
            FinalSize += sizeof(uint16_t);

            // 4. Codec Type (1 byte) - 0x06 for Opus PLC
            aFinal[FinalSize++] = 0x06;

            // 5. Track where Size 1 lives
            size_t totalDataLengthOffset = FinalSize;
            FinalSize += sizeof(uint16_t); // Reserve 2 bytes

            // 6. Sub-Frame Header size (2 bytes) - MUST be exactly raw opusBytes count
            uint16_t frameSize = (uint16_t)opusBytes;
            memcpy(&aFinal[FinalSize], &frameSize, sizeof(uint16_t));
            FinalSize += sizeof(uint16_t);

            // 7. Sequence Number (2 bytes)
            uint16_t seq = m_nosteamSeqNum[playerSlot]++;
            memcpy(&aFinal[FinalSize], &seq, sizeof(uint16_t));
            FinalSize += sizeof(uint16_t);

            // 8. Raw Opus Audio Payload
            memcpy(&aFinal[FinalSize], opusBuf, opusBytes);
            FinalSize += opusBytes;

            uint16_t totalRemainingBytes = (uint16_t)(sizeof(uint16_t) + sizeof(uint16_t) + opusBytes);
            memcpy(&aFinal[totalDataLengthOffset], &totalRemainingBytes, sizeof(uint16_t));

            // 10. Compute and append CRC32 checksum over the complete array built so far
            uint32_t crc = UTIL_CRC32(aFinal, FinalSize);
            memcpy(&aFinal[FinalSize], &crc, sizeof(uint32_t));
            FinalSize += sizeof(uint32_t);

            for (int i = 0; i < maxClients; i++)
            {
                IClient *pToClient = iserver->GetClient(i);
                if (!pToClient || !pToClient->IsConnected() || !pToClient->IsActive() || pToClient->IsFakeClient())
                    continue;
                if (g_bIsNoSteam[i + 1])
                    continue;
                if (g_bClientMuted[i + 1][playerSlot + 1])
                    continue;
                // debugging voice packets
                /*
                int dumpLen = (int)FinalSize < 32 ? (int)FinalSize : 32;
                char hexBuf[32 * 3 + 1];
                int pos = 0;
                for (int i = 0; i < dumpLen; i++)
                {
                    static const char hex[] = "0123456789ABCDEF";
                    hexBuf[pos++] = hex[(aFinal[i] >> 4) & 0xF];
                    hexBuf[pos++] = hex[aFinal[i] & 0xF];
                    hexBuf[pos++] = ' ';
                }
                hexBuf[pos] = '\0';
                smutils->LogMessage(myself, "CVoice::HandleNoSteamVoiceData packet: FinalSize=%d first %d bytes: %s", (int)FinalSize, dumpLen, hexBuf);
                */
                SendVoiceDataMsg(playerSlot, pToClient, aFinal, (int)FinalSize, 0);
            }
            framesEmitted++;
        }

        if (framesEmitted > 0)
        {
            if (m_nosteamAvailableTime[playerSlot] < getTime())
                m_nosteamAvailableTime[playerSlot] = getTime();
            m_nosteamAvailableTime[playerSlot] += (double)framesEmitted * (480.0 / 24000.0);
        }
    }
}