#include "IR_DecoderRaw.h"
#include "IR_Encoder.h"
#include <cstdio>
#include <cstring>

#if IR_GLITCH_REJECT_PHASE_NUDGE
/** Подтяжка опоры фазы после отброса шипа (как irfoxGlitchPhaseNudgeUs в плагине). */
static inline void irGlitchPhaseNudge(uint32_t edgeTime, uint16_t riseSync, volatile uint32_t &prevRise)
{
    if (edgeTime > riseSync)
    {
        const uint32_t nudged = edgeTime - riseSync;
        if (nudged > prevRise && nudged < edgeTime)
            prevRise = nudged;
    }
}
#endif

static inline uint8_t irPulseFilterHoldbackEdges()
{
    uint8_t hb = (uint8_t)IR_INPUT_FILTER_HOLDBACK_EDGES;
    if (hb < 2U)
        hb = 2U;
    if (hb > 4U)
        hb = 4U;
    return hb;
}

IR_DecoderRaw::IR_DecoderRaw(const uint8_t pin, uint16_t addr, IR_Encoder *encPair) : encoder(encPair)
{
    setPin(pin);
    id = addr;
    prevRise = prevFall = prevPrevFall = prevPrevRise = 0;
    if (encPair != nullptr)
    {
        encPair->decPair = this;
    }

#ifdef IRDEBUG
    pinMode(wrHigh, OUTPUT);
    pinMode(wrLow, OUTPUT);
    pinMode(writeOp, OUTPUT);
    pinMode(errOut, OUTPUT);
    pinMode(up, OUTPUT);
    pinMode(down, OUTPUT);
#endif
}

bool IR_DecoderRaw::isSubOverflow()
{
    noInterrupts();
    volatile bool ret = isSubBufferOverflow;
    interrupts();
    return ret;
}

bool IR_DecoderRaw::availableRaw()
    {
        if (isAvailable)
        {
            isAvailable = false;
            return true;
        }
        else
        {
            return false;
        }
    };

void IR_DecoderRaw::pulseFilterResetStats()
{
    pulseFilterDropFilteredOverflow = 0;
    pulseFilterDropHoldOverflow = 0;
    pulseFilterDropGlitchPairs = 0;
}

//////////////////////////////////// isr ///////////////////////////////////////////
volatile uint32_t time_;

void IR_DecoderRaw::isr()
{
    noInterrupts();
    time_ = micros();
    interrupts();
    if (time_ < oldTime)
    {
        time_ += 1000;
    }
    oldTime = time_;

    FrontStorage edge;
    edge.dir = port->IDR & mask;
    edge.time = time_;

#if defined(IR_EDGE_TRACE)
    edgeTracePush(edge.time, edge.dir ? 1u : 0u,
                  isPairSending ? (uint8_t)IR_EDGE_TRACE_F_SKIP_DECODE : 0u);
#endif

    if (isPairSending)
    {
        return;
    }

    subBuffer.push(edge);
}

////////////////////////////////////////////////////////////////////////////////////

void IR_DecoderRaw::firstRX()
{
#if defined(IRDEBUG_SERIAL_PACK)
    packTraceResetFrame();
#endif

    errors.reset();
    packSize = 0;

    isBufferOverflow = false;
    isAvailable = false;
    bufBitPos = 0;
    isData = true;
    i_dataBuffer = 0;
    nextControlBit = bitPerByte;
    i_syncBit = 0;
    isWrongPack = false;

    isPreamb = true;
    riseSyncTime = bitTime /* 1100 */;
#ifdef IRDEBUG
    wrCounter = 0;
#endif
    memset(dataBuffer, 0x00, dataByteSizeMax);
    pulseFilterReset();
    preambleResetToIdle();
}

void IR_DecoderRaw::listenStart()
{
    if (isReciveRaw && ((micros() - lastEdgeTime) > IR_timeout * 2U))
    {
#if defined(IRDEBUG_SERIAL_PACK)
        packTraceOnTimeoutOrAbort(true);
#endif
        isReciveRaw = false;
        firstRX();
    }
}


// ---- быстрая проверка конца пакета ---------------------------------
inline void IR_DecoderRaw::checkTimeout()
{
    if (!isRecive) return;     // уже не принимаем – нечего проверять

    if (micros() - lastEdgeTime > IR_timeout * 2U)
    {
#if defined(IRDEBUG_SERIAL_PACK)
        packTraceOnTimeoutOrAbort(false);
#endif
        isRecive = false;      // приём завершён
        msgTypeReceive = 0;
        // firstRX();             // подготовка к новому пакету
        lastEdgeTime = micros(); // защита от повторного срабатывания
    }
}
// ====================================================================

void IR_DecoderRaw::tick()
{
    FrontStorage currentFront;
    bool hasCurrentFront = false;
    FrontStorage rawFront;
    bool hasRawFront = false;
    noInterrupts();
    FrontStorage *rawPtr = subBuffer.pop();
    if (rawPtr != nullptr)
    {
        rawFront = *rawPtr;
        hasRawFront = true;
    }
    interrupts();

    if (IR_INPUT_MIN_PULSE_US > 0U)
    {
        if (hasRawFront)
            pulseFilterFeedOneRaw(rawFront);
        else
            pulseFilterFlushTimeout(micros());

        noInterrupts();
        FrontStorage *flt = filteredSubBuffer.pop();
        if (flt != nullptr)
        {
            currentFront = *flt;
            hasCurrentFront = true;
        }
        interrupts();
    }
    else if (hasRawFront)
    {
        currentFront = rawFront;
        hasCurrentFront = true;
    }

    if (!hasCurrentFront)
    {
        isSubBufferOverflow = false;
        bool rawQueueHasPending = false;
        bool filteredQueueHasPending = false;
        noInterrupts();
        rawQueueHasPending = !subBuffer.isEmpty();
        if (IR_INPUT_MIN_PULSE_US > 0U)
            filteredQueueHasPending = !filteredSubBuffer.isEmpty();
        interrupts();
        const bool filterHoldHasPending = (IR_INPUT_MIN_PULSE_US > 0U) && (pulseFilterHoldCount > 0U);
        const bool hasPendingEdges = hasRawFront || rawQueueHasPending || filteredQueueHasPending || filterHoldHasPending;

        if (!hasPendingEdges)
        {
            listenStart();
            checkTimeout();
        }
#if defined(IR_EDGE_TRACE)
        while (edgeTraceFlushChunk(Serial, 48) > 0) {}
#endif
        return;
    } // Если данных нет - ничего не делаем

    if (preambleProcessEdge(currentFront))
    {
        lastEdgeTime = currentFront.time;
        goto END;
    }

    lastEdgeTime = currentFront.time;     // запоминаем любой фронт

    ////////////////////////////////////////////////////////////////////////////////////////////////////////////

    if (currentFront.dir)
    { // Если __/``` ↑
        const uint32_t candRp = currentFront.time - prevRise;
        const uint32_t candHt = currentFront.time - prevFall;
        const uint32_t candLt = prevFall - prevRise;

#if IR_SHORT_LOW_GLITCH_REJECT
        const bool short_low_glitch =
            isRecive && !isPreamb && candHt < (riseTimeMin / 8U) && candLt >= riseTimeMin &&
            candRp >= riseTimeMin && candRp <= IR_timeout;
        if (short_low_glitch)
        {
            errors.other++;
#if IR_GLITCH_REJECT_PHASE_NUDGE
            irGlitchPhaseNudge(currentFront.time, riseSyncTime, prevRise);
#endif
            goto END;
        }
#endif
#if IR_MICRO_GAP_RISE_REJECT
        const bool micro_gap_cand_lt_ok =
            (candLt >= riseTimeMin) || (candLt >= (riseTimeMin / 4U) && candLt < riseTimeMin);
        const bool micro_gap_rise = isRecive && !isPreamb && candHt < (riseTimeMin / 8U) && micro_gap_cand_lt_ok &&
                                    candRp >= (riseTimeMin / 4U) && candRp < riseTimeMin && candRp <= IR_timeout;
        if (micro_gap_rise)
        {
            errors.other++;
#if IR_GLITCH_REJECT_PHASE_NUDGE
            irGlitchPhaseNudge(currentFront.time, riseSyncTime, prevRise);
#endif
            goto END;
        }
#endif
        if (candRp <= riseTimeMax / 4U && !highCount && !lowCount)
        {
            errors.other++;
            goto END;
        }

        if (candRp > riseTimeMax / 4 || highCount || lowCount)
        { // комплексный фикс рваной единицы
            risePeriod = candRp;
            highTime = candHt;
            lowTime = candLt;
            prevRise = currentFront.time;

            if (
                risePeriod > UINT32_MAX - IR_timeout * 10 ||
                highTime > UINT32_MAX - IR_timeout * 10 ||
                lowTime > UINT32_MAX - IR_timeout * 10 ||
                prevRise > UINT32_MAX - IR_timeout * 10)
            {
#ifdef IRDEBUG
                errPulse(down, 50);

                // Serial.print("\n");

                // Serial.print("risePeriod:    ");
                // Serial.println(risePeriod);

                // Serial.print("highTime:           ");
                // Serial.println(highTime);

                // Serial.print("lowTime:            ");
                // Serial.println(lowTime);

                // Serial.print("prevRise:                  ");
                // Serial.println(prevRise);
#endif
            }
        }
        else
        {
            errors.other++;
        }
    }
    else
    { // Если ```\__ ↓

        if (currentFront.time - prevFall > riseTimeMin / 4)
        {
            prevFall = currentFront.time;
        }
        else
        {
            errors.other++;
        }
    }
#ifdef IRDEBUG
    // goto END; //~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
#endif
    //----------------------------------------------------------------------------------
#ifdef IRDEBUG
    digitalWrite(errOut, currentFront.dir);
#endif

    if (risePeriod > IR_timeout || isBufferOverflow || risePeriod < riseTimeMin || isWrongPack)
    // ~Мы в пределах таймаута и буффер не переполнен и fix дроблёных единиц
    {
        goto END;
    }

    // определить направление фронта
    if (currentFront.dir)
    { // Если __/``` ↑
        highCount = 0;
        lowCount = 0;
        allCount = 0;
        bool invertErr = false;
// #ifdef IRDEBUG
//         Serial.print("\n");

//         Serial.print("wrCounter:    ");
//         Serial.println(wrCounter++);

//         Serial.print("risePeriod:           ");
//         Serial.println(risePeriod);

//         Serial.print("highTime:        ");
//         Serial.println(highTime);

//         Serial.print("lowTime:         ");
//         Serial.println(lowTime);
// #endif

        if (aroundRise(risePeriod))
        { // тактирование есть, сигнал хороший - без ошибок(?)

            if (highTime > lowTime)
            { // 1
#ifdef IRDEBUG
                errPulse(wrHigh, 1);
#endif
                writeToBuffer(HIGH);
            }
            else
            { // 0
#ifdef IRDEBUG
                errPulse(wrLow, 1);
#endif
                writeToBuffer(LOW);
            }
        }
        else
        {                                              // пропущены такты! сигнал средний // ошибка пропуска
            highCount = ceil_div(highTime, riseTime);  // предполагаемое колличество HIGH битов
            lowCount = ceil_div(lowTime, riseTime);    // предполагаемое колличество LOW битов
            allCount = ceil_div(risePeriod, riseTime); // предполагаемое колличество всего битов

            if (highCount == 0 && highTime > riseTime / 3)
            { // fix короткой единицы (?)после пропуска нулей(?)
                highCount++;
                errors.other++;
#ifdef IRDEBUG
                errPulse(up, 50);
#endif
            }

            if (lowCount + highCount > allCount)
            { // fix ошибочных сдвигов
                if (lowCount > highCount)
                { // Лишние нули
                    lowCount = allCount - highCount;
                    errors.lowSignal += lowCount;
#ifdef IRDEBUG
                    // errPulse(errOut, 3);
                    errPulse(down, 40);
                    errPulse(up, 10);
                    errPulse(down, 40);
#endif
                }
                else if (lowCount < highCount)
                { // Лишние единицы
                    highCount = allCount - lowCount;
                    errors.highSignal += highCount;
#ifdef IRDEBUG
                    errPulse(down, 10);
                    errPulse(up, 40);
                    errPulse(down, 10);
// errPulse(errOut, 4);
#endif
                    // неизвестный случай Инверсит след бит или соседние
                    // Очень редко
                    // TODO: Отловить проверить
                }
                else if (lowCount == highCount)
                {
#ifdef IRDEBUG
                    errPulse(down, 40);
                    errPulse(up, 40);
                    errPulse(down, 40);
#endif
                    invertErr = true;
                    // Serial.print("...");
                    errors.other += allCount;
                }
                // errorCounter += allCount;
            }

            // errorCounter += allCount;
            // errors.other+=allCount;
            if (lowCount < highCount)
            {
                errors.highSignal += highCount;
            }
            else
            {
                errors.lowSignal += lowCount;
            }

            // errPulse(errOut, 1);

            for (int8_t i = 0; i < lowCount && 8 - i; i++)
            { // отправка LOW битов, если есть
                if (i == lowCount - 1 && invertErr)
                {
                    invertErr = false;
                    writeToBuffer(HIGH, true);
#ifdef IRDEBUG
                    errPulse(wrHigh, 1);
#endif
                }
                else
                {
                    writeToBuffer(LOW);
#ifdef IRDEBUG
                    errPulse(wrLow, 1);
#endif
                }
            }

            for (int8_t i = 0; i < highCount && 8 - i; i++)
            { // отправка HIGH битов, если есть
                if (i == highCount - 1 && invertErr)
                {
                    invertErr = false;
                    writeToBuffer(LOW, true);
#ifdef IRDEBUG
                    errPulse(wrLow, 1);
#endif
                }
                else
                {
                    writeToBuffer(HIGH);
#ifdef IRDEBUG
                    errPulse(wrHigh, 1);
#endif
                }
            }
        }
    }
    else
    { // Если ```\__ ↓
    }

////////////////////////////////////////////////////////////////////////////////////////////////////////////
END:;
#if defined(IR_EDGE_TRACE)
    while (edgeTraceFlushChunk(Serial, 48) > 0) {}
#endif
}

void IR_DecoderRaw::writeToBuffer(bool bit, bool packTraceInvertFix)
{
#if !defined(IRDEBUG_SERIAL_PACK)
    (void)packTraceInvertFix;
#endif
    if (i_dataBuffer > dataByteSizeMax * 8)
    { // проверка переполнения
        isBufferOverflow = true;
#if defined(IRDEBUG_SERIAL_PACK)
        if (packTraceOpen)
            packTraceEmitErrorFlash(F("ERROR: buffer overflow"));
#endif
    }
    if (isBufferOverflow || isPreamb || isWrongPack)
    {
        isRecive = false;
        isReciveRaw = false;
        preambleResetToIdle();
        msgTypeReceive = 0;
        return;
    }

    // Переключение флага, data или syncBit
    if (bufBitPos == nextControlBit)
    {
        nextControlBit += (isData ? syncBits : bitPerByte); // маркер следующего переключения
        isData = !isData;
        i_syncBit = 0;   // сброс счетчика битов синхронизации
        err_syncBit = 0; // сброс счетчика ошибок синхронизации
    }

    if (isData)
    { // Запись битов в dataBuffer
        dataBuffer[(i_dataBuffer / 8)] |= bit << (7 - i_dataBuffer % 8); // Запись в буффер
        i_dataBuffer++;
        bufBitPos++;
#if defined(IRDEBUG_SERIAL_PACK)
        if (packTraceInvertFix)
        {
            packTracePushChar('`');
            packTracePushChar(bit ? '1' : '0');
            packTracePushChar('`');
        }
        else
            packTracePushBit(bit);
#endif
    }
    else
    {
        //********************************* Проверка контрольных sync битов *******************************//
        ////////////////////// Исправление лишнего нуля ///////////////////////
        if (i_syncBit == 0)
        { // Первый бит синхронизации
            if (bit != (dataBuffer[((i_dataBuffer - 1) / 8)] >> (7 - (i_dataBuffer - 1) % 8) & 1))
            {
                bufBitPos++;
                i_syncBit++;
#if defined(IRDEBUG_SERIAL_PACK)
                packTracePushBit(bit);
#endif
            }
            else
            {
                i_syncBit = 0;
                errors.other++;
                err_syncBit++;
                const bool fatalSync = (err_syncBit >= syncBits);
                if (fatalSync)
                {
#if defined(IRDEBUG_SERIAL_PACK) && defined(IRDEBUG_SERIAL_SOFT_REJECT)
                    if (packTraceSoftReject())
                    {
                        packTraceHadWrongSync = true;
                        packTraceForceEndSyncPhase();
                        err_syncBit = 0;
                        i_syncBit = 0;
                        isWrongPack = false;
                    }
                    else
#endif
                    {
                        isWrongPack = true;
#if defined(IRDEBUG_SERIAL_PACK)
                        packTraceEmitErrorFlash(F("ERROR: Wrong sync bit"));
#endif
                    }
                }
            }
        }
        else
        { // Последующие биты синхронизации
            bufBitPos++;
            i_syncBit++;
#if defined(IRDEBUG_SERIAL_PACK)
            packTracePushBit(bit);
#endif
        }
        isWrongPack = (err_syncBit >= syncBits);
    } //**************************************************************************************************//

#ifdef IRDEBUG
    bit ? infoPulse(writeOp, 2) : infoPulse(writeOp, 1);
#endif

    if (!isAvailable && isData && !isWrongPack)
    {
        if (i_dataBuffer == 8 * msgBytes)
        { // Ппервый байт
            packSize = dataBuffer[0] & IR_MASK_MSG_INFO;
        }

        // Тип приёма (для isReceive): выставляем сразу после первого байта, ДО проверки «Конец».
        // Иначе при packSize==1 один и тот же шаг i_dataBuffer==8 одновременно «закрывает» кадр (msgTypeReceive=0)
        // и снова выставляет msgTypeReceive ниже — флаг залипает, пока не придёт ошибка/другой кадр.
        if (packSize && (i_dataBuffer == 8))
        {
            msgTypeReceive = (dataBuffer[0] >> 5) | 0b11111000;
        }

        if (packSize && (i_dataBuffer == packSize * bitPerByte))
        { // Конец
            packInfo.buffer = dataBuffer;
            packInfo.crc = crcValue;
            packInfo.err = errors;
            packInfo.packSize = packSize;
            packInfo.rTime = riseSyncTime;

            isRecive = false;
            isReciveRaw = false;
            preambleResetToIdle();
            msgTypeReceive = 0;
            isAvailable = crcCheck(packSize - crcBytes, crcValue);

#ifdef BRUTEFORCE_CHECK
            {
                uint16_t packTraceBfByte = 0;
                uint8_t packTraceBfBit = 0;
                bool packTraceBfMark = false;
                if (!isAvailable) // Исправление первого бита // Очень большая затычка...
                    for (size_t i = 0; i < min(uint16_t(packSize - crcBytes * 2U), uint16_t(dataByteSizeMax)); ++i)
                    {
                        for (int j = 0; j < 8; ++j)
                        {
                            // инвертируем бит
                            dataBuffer[i] ^= 1 << j;

                            isAvailable =
                                crcCheck(min(uint16_t(packSize - crcBytes), uint16_t(dataByteSizeMax - 1U)), crcValue);
                            // обратно инвертируем бит в исходное состояние

                            if (isAvailable)
                            {
                                packTraceBfByte = static_cast<uint16_t>(i);
                                packTraceBfBit = static_cast<uint8_t>(j);
                                packTraceBfMark = true;
                                goto OUT_BRUTEFORCE;
                            }
                            else
                            {
                                dataBuffer[i] ^= 1 << j;
                            }
                        }
                    }
            OUT_BRUTEFORCE:
#if defined(IRDEBUG_SERIAL_PACK)
                if (packTraceBfMark)
                    packTraceWrapDataBitInBackticks(packTraceBfByte, packTraceBfBit);
#endif
            }
#endif
#if defined(IRDEBUG_SERIAL_PACK)
            if (isAvailable)
                packTraceEmitEndOk(static_cast<uint8_t>(packSize));
            else
                packTraceEmitEndBadCrc(static_cast<uint8_t>(packSize));
#endif
            if (!isAvailable && packSize > 0 && packSize <= dataByteSizeMax) {
                memcpy(rejectBuffer, dataBuffer, packSize);
                rejectPackSize = static_cast<uint8_t>(packSize);
                isRejectAvailable = true;
            }
        }
    }

    //////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
}

bool IR_DecoderRaw::crcCheck(uint8_t len, crc_t &crc)
{
    bool crcOK = false;

    crc = 0;
    crc = (crc8(dataBuffer, 0, len, poly1) << 8) & ~((crc_t)0xFF);
    crc |= crc8(dataBuffer, 0, len + 1, poly2) & (crc_t)0xFF;

    if (dataBuffer[len] == (crc >> 8) & 0xFF &&
        dataBuffer[len + 1] == (crc & 0xFF))
    {
        crcOK = true;
    }
    else
    {
        crcOK = false;
    }

    return crcOK;
}

bool IR_DecoderRaw::availableReject()
{
    if (!isRejectAvailable)
        return false;
    isRejectAvailable = false;
    return true;
}

uint16_t IR_DecoderRaw::ceil_div(uint16_t val, uint16_t divider)
{
    int ret = val / divider;
    if ((val << 4) / divider - (ret << 4) >= 8)
        ret++;
    return ret;
}

#if defined(IR_EDGE_TRACE)

void IR_DecoderRaw::edgeTracePush(uint32_t t_us, uint8_t level, uint8_t flags)
{
    const uint16_t cap = static_cast<uint16_t>(IR_EDGE_TRACE_CAPACITY);
    noInterrupts();
    const uint16_t w = edgeTrace_w;
    const uint16_t r = edgeTrace_r;
    const uint16_t next = static_cast<uint16_t>((w + 1u) % cap);
    if (next == r)
    {
        edgeTrace_overflow = true;
        interrupts();
        return;
    }
    edgeTrace_buf[w].t_us = t_us;
    edgeTrace_buf[w].level = level ? 1u : 0u;
    edgeTrace_buf[w].flags = flags;
    edgeTrace_w = next;
    interrupts();
}

void IR_DecoderRaw::edgeTraceClear()
{
    noInterrupts();
    edgeTrace_w = 0;
    edgeTrace_r = 0;
    edgeTrace_overflow = false;
    interrupts();
}

uint16_t IR_DecoderRaw::edgeTracePendingCount() const
{
    noInterrupts();
    const uint16_t w = edgeTrace_w;
    const uint16_t r = edgeTrace_r;
    interrupts();
    const uint16_t cap = static_cast<uint16_t>(IR_EDGE_TRACE_CAPACITY);
    if (w >= r)
        return static_cast<uint16_t>(w - r);
    return static_cast<uint16_t>(cap - r + w);
}

uint16_t IR_DecoderRaw::edgeTraceFlushChunk(Print &out, uint16_t maxRec)
{
    if (maxRec == 0)
        maxRec = 48;
    constexpr uint16_t kStackCap = 64;
    if (maxRec > kStackCap)
        maxRec = kStackCap;

    const uint16_t cap = static_cast<uint16_t>(IR_EDGE_TRACE_CAPACITY);
    noInterrupts();
    const uint16_t w = edgeTrace_w;
    const uint16_t r = edgeTrace_r;
    uint16_t avail = (w >= r) ? static_cast<uint16_t>(w - r) : static_cast<uint16_t>(cap - r + w);
    uint16_t toCopy = (avail > maxRec) ? maxRec : avail;
    const bool truncated = (avail > toCopy);
    if (toCopy == 0)
    {
        interrupts();
        return 0;
    }

    uint8_t tmp[kStackCap * 6];
    for (uint16_t i = 0; i < toCopy; ++i)
    {
        const uint16_t idx = static_cast<uint16_t>((r + i) % cap);
        memcpy(tmp + i * 6u, &edgeTrace_buf[idx], 6u);
    }
    edgeTrace_r = static_cast<uint16_t>((r + toCopy) % cap);
    const bool ovf = edgeTrace_overflow;
    interrupts();

    uint8_t meta = 0;
    if (ovf)
        meta |= 0x01u;
    if (truncated)
        meta |= 0x02u;

    uint8_t line[3 + kStackCap * 6];
    line[0] = meta;
    line[1] = static_cast<uint8_t>(toCopy & 0xFFu);
    line[2] = static_cast<uint8_t>((toCopy >> 8) & 0xFFu);
    memcpy(line + 3, tmp, toCopy * 6u);

    out.print(F("\n@IRF1v1:"));
    static const char hd[] = "0123456789abcdef";
    const uint16_t lineLen = static_cast<uint16_t>(3u + toCopy * 6u);
    for (uint16_t i = 0; i < lineLen; ++i)
    {
        const uint8_t b = line[i];
        out.write(hd[b >> 4]);
        out.write(hd[b & 0x0Fu]);
    }
    out.write('\n');
    return toCopy;
}

#endif // IR_EDGE_TRACE

#if defined(IRDEBUG_SERIAL_PACK)

struct IrPackTraceSeg
{
    uint8_t isSync;
    uint8_t nbits;  // число логических бит (данные) или символов синхры
    uint8_t nchars; // сырых символов в b (данные: 8…24 из‑за `0`/`1`)
    char b[24];
};

namespace {

void ptPrintHexU8(uint8_t v)
{
    static const char hd[] = "0123456789ABCDEF";
    Serial.print(hd[v >> 4]);
    Serial.print(hd[v & 0x0Fu]);
}

/** Тройной пробел перед началом блока: msg→from, from→to, to→data, data→CRC. */
static bool ptRawLeadTriple(uint8_t byteIndex, uint8_t framePs)
{
    if (byteIndex == 1 || byteIndex == 3)
        return true;
    if (framePs > 7 && byteIndex == 5)
        return true;
    if (framePs >= 7 && byteIndex == static_cast<uint8_t>(framePs - 2))
        return true;
    return false;
}

/** В IR raw: только 0/1 из flex-сегмента (без `), takeBits логических бит после skipLogical. */
static void ptEmitRawFlexSliceSerial(const char *s, uint8_t nbytes, uint8_t skipLogical, uint8_t takeBits)
{
    size_t i = 0;
    uint8_t logical = 0;
    uint8_t emitted = 0;
    while (i < nbytes && emitted < takeBits)
    {
        if (s[i] == '`' && i + 2u < nbytes && (s[i + 1] == '0' || s[i + 1] == '1') && s[i + 2] == '`')
        {
            if (logical >= skipLogical)
            {
                Serial.print(s[i + 1]);
                ++emitted;
            }
            i += 3;
            ++logical;
        }
        else if (s[i] == '0' || s[i] == '1')
        {
            if (logical >= skipLogical)
            {
                Serial.print(s[i]);
                ++emitted;
            }
            ++i;
            ++logical;
        }
        else
            break;
    }
}

static bool ptTryConsumeFlexDataBit(const char *buf, uint16_t len, uint16_t &pos, IrPackTraceSeg &d)
{
    if (pos + 2 < len && buf[pos] == '`' && (buf[pos + 1] == '0' || buf[pos + 1] == '1') && buf[pos + 2] == '`')
    {
        if (d.nchars + 3u > sizeof(d.b))
            return false;
        d.b[d.nchars++] = '`';
        d.b[d.nchars++] = buf[pos + 1];
        d.b[d.nchars++] = '`';
        pos = static_cast<uint16_t>(pos + 3u);
        return true;
    }
    if (pos < len && (buf[pos] == '0' || buf[pos] == '1'))
    {
        if (d.nchars + 1u > sizeof(d.b))
            return false;
        d.b[d.nchars++] = buf[pos++];
        return true;
    }
    return false;
}

} // namespace

void IR_DecoderRaw::packTraceResetFrame()
{
    packTraceOpen = false;
    packTraceHadWrongSync = false;
    packTraceLen = 0;
    packTraceBitBuf[0] = '\0';
}

void IR_DecoderRaw::packTracePushChar(char c)
{
    if (packTraceLen + 1u < kPackTraceBufCap)
    {
        packTraceBitBuf[packTraceLen++] = c;
        packTraceBitBuf[packTraceLen] = '\0';
    }
}

void IR_DecoderRaw::packTracePushBit(bool bit) { packTracePushChar(bit ? '1' : '0'); }

void IR_DecoderRaw::packTraceWrapDataBitInBackticks(uint16_t byteIndex, uint8_t bitInByte)
{
    const uint32_t target = uint32_t(byteIndex) * 8u + bitInByte;
    uint32_t dbit = 0;
    uint16_t pos = 0;
    bool inData = true;
    uint16_t len = packTraceLen;
    if (len >= kPackTraceBufCap)
        len = kPackTraceBufCap - 1u;

    while (pos < len)
    {
        if (inData)
        {
            uint8_t bitLen = 0;
            if (pos + 2 < len && packTraceBitBuf[pos] == '`' && packTraceBitBuf[pos + 2] == '`' &&
                (packTraceBitBuf[pos + 1] == '0' || packTraceBitBuf[pos + 1] == '1'))
                bitLen = 3;
            else if (packTraceBitBuf[pos] == '0' || packTraceBitBuf[pos] == '1')
                bitLen = 1;
            else
                return;

            if (dbit == target)
            {
                if (bitLen == 3)
                    return;
                if (packTraceLen + 2u >= kPackTraceBufCap)
                    return;
                const uint8_t finalBit =
                    static_cast<uint8_t>((dataBuffer[byteIndex] >> (7u - bitInByte)) & 1u);
                const char ch = finalBit ? '1' : '0';
                memmove(packTraceBitBuf + pos + 2, packTraceBitBuf + pos, packTraceLen - pos);
                packTraceBitBuf[pos] = '`';
                packTraceBitBuf[pos + 1] = ch;
                packTraceBitBuf[pos + 2] = '`';
                packTraceLen += 2;
                if (packTraceLen < kPackTraceBufCap)
                    packTraceBitBuf[packTraceLen] = '\0';
                return;
            }
            ++dbit;
            pos = static_cast<uint16_t>(pos + bitLen);
            if ((dbit % 8u) == 0u)
                inData = false;
        }
        else
        {
            uint8_t sc = 0;
            while (pos < len && sc < syncBits)
            {
                const char c = packTraceBitBuf[pos];
                if (c == '0' || c == '1' || c == '?')
                {
                    ++pos;
                    ++sc;
                }
                else
                    break;
            }
            inData = true;
        }
    }
}

bool IR_DecoderRaw::packTraceSoftReject() const
{
#if defined(IRDEBUG_SERIAL_SOFT_REJECT)
    return true;
#else
    return false;
#endif
}

void IR_DecoderRaw::packTraceForceEndSyncPhase()
{
    for (uint8_t i = 0; i < syncBits; i++)
        packTracePushChar('?');

    const uint8_t cycLen = bitPerByte + syncBits;
    const uint16_t cyc = uint16_t(bufBitPos / cycLen);
    bufBitPos = uint16_t((cyc + 1u) * cycLen);
    if (bufBitPos == nextControlBit)
    {
        nextControlBit += (isData ? syncBits : bitPerByte);
        isData = !isData;
        i_syncBit = 0;
        err_syncBit = 0;
    }
}

void IR_DecoderRaw::packTraceEmitHex(uint8_t byteCount) const
{
    Serial.print(F("IR hex:"));
    for (uint8_t i = 0; i < byteCount && i < dataByteSizeMax; i++)
    {
        Serial.print(' ');
        ptPrintHexU8(dataBuffer[i]);
    }
    Serial.println();
}

void IR_DecoderRaw::packTraceEmitRawBitsLine(bool endWithNewline) const
{
    Serial.print(F("IR raw: "));
    uint16_t len = packTraceLen;
    if (len >= kPackTraceBufCap)
        len = kPackTraceBufCap - 1u;
    const char *buf = packTraceBitBuf;
    uint16_t pos = 0;
    uint8_t byteIndex = 0;
    bool firstSeg = true;
    const uint8_t framePs =
        (i_dataBuffer >= 8) ? static_cast<uint8_t>(dataBuffer[0] & IR_MASK_MSG_INFO) : 0;

    while (pos < len)
    {
        IrPackTraceSeg d{};
        d.isSync = 0;
        while (pos < len && d.nbits < 8)
        {
            const uint16_t posBefore = pos;
            if (!ptTryConsumeFlexDataBit(buf, len, pos, d))
                break;
            if (pos == posBefore)
                break;
            ++d.nbits;
        }
        if (!d.nbits)
            break;

        if (!firstSeg)
        {
            if (ptRawLeadTriple(byteIndex, framePs))
                Serial.print(F("   "));
            else
                Serial.print(' ');
        }
        firstSeg = false;

        if (d.nbits < 8)
        {
            ptEmitRawFlexSliceSerial(d.b, d.nchars, 0, d.nbits);
            break;
        }

        if (byteIndex == 0u)
        {
            ptEmitRawFlexSliceSerial(d.b, d.nchars, 0, 3);
            Serial.print(' ');
            ptEmitRawFlexSliceSerial(d.b, d.nchars, 3, 5);
        }
        else
            ptEmitRawFlexSliceSerial(d.b, d.nchars, 0, 8);

        ++byteIndex;

        if (pos >= len)
            break;

        IrPackTraceSeg s{};
        s.isSync = 1;
        while (pos < len && s.nbits < syncBits)
        {
            const char c = buf[pos];
            if (c != '0' && c != '1' && c != '?')
                break;
            if (s.nchars >= sizeof(s.b))
                break;
            s.b[s.nchars++] = c;
            ++s.nbits;
            ++pos;
        }
        if (s.nbits)
        {
            Serial.print(' ');
            for (uint8_t i = 0; i < s.nbits; ++i)
                Serial.print(s.b[i]);
        }
    }
    if (endWithNewline)
        Serial.println();
}

void IR_DecoderRaw::packTraceEmitErrorFlash(const __FlashStringHelper *msg)
{
    Serial.println();
    packTraceEmitRawBitsLine(false);
    Serial.print(F(" => "));
    Serial.println(msg);
    {
        uint16_t nb = i_dataBuffer / 8u;
        if (nb > dataByteSizeMax)
            nb = dataByteSizeMax;
        packTraceEmitHex(static_cast<uint8_t>(nb));
    }
    packTraceResetFrame();
}

void IR_DecoderRaw::packTraceEmitEndOk(uint8_t packSize)
{
    Serial.println();
    packTraceEmitRawBitsLine(false);
    Serial.print(F(" => OK: "));
    irPackTracePrintOkCommand(dataBuffer, packSize);
    Serial.println();
    packTraceEmitHex(packSize);
    packTraceResetFrame();
}

void IR_DecoderRaw::packTraceEmitEndBadCrc(uint8_t packSize)
{
    Serial.println();
    packTraceEmitRawBitsLine(false);
    Serial.println(F(" => ERROR: Wrong CRC"));
    packTraceEmitHex(packSize);
    packTraceResetFrame();
}

void IR_DecoderRaw::packTraceOnTimeoutOrAbort(bool fromListenStart)
{
    (void)fromListenStart;
    if (!packTraceOpen)
        return;
    const uint16_t expected = (i_dataBuffer >= 8) ? uint16_t(dataBuffer[0] & IR_MASK_MSG_INFO) : 0;
    uint16_t gotBytes = i_dataBuffer / 8;
    if (gotBytes > dataByteSizeMax)
        gotBytes = dataByteSizeMax;
    Serial.println();
    packTraceEmitRawBitsLine(false);
    Serial.print(F(" => ERROR: TIMEOUT, rx_data_size = "));
    Serial.print(expected);
    Serial.print(F(", but only "));
    Serial.print(gotBytes);
    Serial.println(F(" bytes received"));
    packTraceEmitHex(static_cast<uint8_t>(gotBytes));
    packTraceResetFrame();
}

__attribute__((weak)) void irPackTracePrintOkCommand(const uint8_t *buf, uint8_t packSize)
{
    (void)buf;
    (void)packSize;
}

#endif // IRDEBUG_SERIAL_PACK

uint32_t IR_DecoderRaw::absDiffU32(uint32_t a, uint32_t b)
{
    return (a > b) ? (a - b) : (b - a);
}

void IR_DecoderRaw::pulseFilterShiftLeft(uint8_t n)
{
    if (n == 0 || pulseFilterHoldCount == 0)
        return;
    if (n >= pulseFilterHoldCount)
    {
        pulseFilterHoldCount = 0;
        return;
    }
    const uint8_t newCount = static_cast<uint8_t>(pulseFilterHoldCount - n);
    for (uint8_t i = 0; i < newCount; ++i)
        pulseFilterHoldEdges[i] = pulseFilterHoldEdges[static_cast<uint8_t>(i + n)];
    pulseFilterHoldCount = newCount;
}

bool IR_DecoderRaw::pulseFilterEmit(const FrontStorage &e)
{
    if (filteredSubBuffer.isFull())
    {
        pulseFilterDropFilteredOverflow++;
        return false;
    }
    filteredSubBuffer.push(e);
    return true;
}

void IR_DecoderRaw::pulseFilterReset()
{
    pulseFilterHoldCount = 0;
    pulseFilterLastRawValid = false;
    pulseFilterLastRawTime = 0;
    while (filteredSubBuffer.pop() != nullptr) {}
}

void IR_DecoderRaw::pulseFilterFeedOneRaw(const FrontStorage &e)
{
    const uint32_t minUs = IR_INPUT_MIN_PULSE_US;
    if (minUs == 0U)
    {
        pulseFilterEmit(e);
        return;
    }

    pulseFilterLastRawTime = e.time;
    pulseFilterLastRawValid = true;

    if (pulseFilterHoldCount >= kPulseFilterHoldCap)
    {
        pulseFilterDropHoldOverflow++;
        pulseFilterEmit(pulseFilterHoldEdges[0]);
        pulseFilterShiftLeft(1);
    }

    pulseFilterHoldEdges[pulseFilterHoldCount++] = e;
    const uint8_t holdback = irPulseFilterHoldbackEdges();

    for (;;)
    {
        if (pulseFilterHoldCount < 2)
            return;

        const uint32_t dt = pulseFilterHoldEdges[1].time - pulseFilterHoldEdges[0].time;
        if (dt < minUs)
        {
            pulseFilterDropGlitchPairs++;
            pulseFilterShiftLeft(2);
            continue;
        }

        if (pulseFilterHoldCount <= holdback)
            return;

        pulseFilterEmit(pulseFilterHoldEdges[0]);
        pulseFilterShiftLeft(1);
    }
}

void IR_DecoderRaw::pulseFilterFlushTimeout(uint32_t nowUs)
{
    if (IR_INPUT_MIN_PULSE_US == 0U || !pulseFilterLastRawValid || pulseFilterHoldCount == 0)
        return;
    const uint32_t waitUs = IR_INPUT_MIN_PULSE_US * (uint32_t)IR_INPUT_FILTER_TIMEOUT_MULT;
    if ((uint32_t)(nowUs - pulseFilterLastRawTime) < waitUs)
        return;

    while (pulseFilterHoldCount > 0)
    {
        if (pulseFilterHoldCount >= 2)
        {
            const uint32_t dt = pulseFilterHoldEdges[1].time - pulseFilterHoldEdges[0].time;
            if (dt < IR_INPUT_MIN_PULSE_US)
            {
                pulseFilterDropGlitchPairs++;
                pulseFilterShiftLeft(2);
                continue;
            }
        }
        pulseFilterEmit(pulseFilterHoldEdges[0]);
        pulseFilterShiftLeft(1);
    }
}

uint32_t IR_DecoderRaw::preambleJitterTolUs(uint32_t baselineUs) const
{
    const uint32_t pct = (baselineUs * (uint32_t)IR_PREAMBLE_JITTER_PCT) / 100U;
    return (pct > (uint32_t)IR_PREAMBLE_JITTER_US_MIN) ? pct : (uint32_t)IR_PREAMBLE_JITTER_US_MIN;
}

bool IR_DecoderRaw::preambleRisePeriodCoarseOk(uint32_t periodUs) const
{
    const uint32_t base = (uint32_t)bitTime;
    const uint32_t minP = (base * (uint32_t)IR_PREAMBLE_PERIOD_MIN_FACTOR_PCT) / 100U;
    const uint32_t maxP = (base * (uint32_t)IR_PREAMBLE_PERIOD_MAX_FACTOR_PCT) / 100U;
    return periodUs >= minP && periodUs <= maxP;
}

void IR_DecoderRaw::preambleResetToIdle()
{
    preambleState = PreambleState::Idle;
    preambleGoodPeriods = 0;
    preambleMeanPeriod = 0;
    preambleCandidateLastEdgeTime = 0;
    preambleCandidateFirstRiseTime = 0;
    preambleCandidateFirstRiseValid = false;
    preambFrontCounter = 0;
    isPreamb = false;
    isWrongPack = false;
    isBufferOverflow = false;
}

void IR_DecoderRaw::preambleStartCandidate(const FrontStorage &front)
{
    preambleState = PreambleState::Candidate;
    preambleGoodPeriods = 0;
    preambleMeanPeriod = 0;
    preambleCandidateLastEdgeTime = front.time;
    preambleCandidateFirstRiseTime = front.time;
    preambleCandidateFirstRiseValid = front.dir;
    preambFrontCounter = 0;
    isPreamb = true;
    isRecive = false;
    isReciveRaw = false;
}

bool IR_DecoderRaw::preambleProcessEdge(const FrontStorage &front)
{
    const uint32_t longSilence = IR_timeout * 2U;
    const uint32_t candTimeout = IR_timeout * (uint32_t)IR_PREAMBLE_CANDIDATE_TIMEOUT_MULT;

    if (preambleState == PreambleState::Idle)
    {
        if (isReciveRaw)
            return false;
        if (!isReciveRaw && front.dir && front.time > prevRise && (front.time - prevRise) > longSilence)
            preambleStartCandidate(front);
    }

    if (preambleState == PreambleState::Candidate)
    {
        if ((uint32_t)(front.time - preambleCandidateLastEdgeTime) > candTimeout)
            preambleStartCandidate(front);

        preambleCandidateLastEdgeTime = front.time;
        if (!front.dir)
            return true;

        if (!preambleCandidateFirstRiseValid)
        {
            preambleCandidateFirstRiseValid = true;
            preambleCandidateFirstRiseTime = front.time;
            return true;
        }

        const uint32_t period = front.time - preambleCandidateFirstRiseTime;
        preambleCandidateFirstRiseTime = front.time;
        if (!preambleRisePeriodCoarseOk(period))
        {
            preambleGoodPeriods = 0;
            preambleMeanPeriod = 0;
            return true;
        }

        if (preambleGoodPeriods == 0)
        {
            preambleGoodPeriods = 1;
            preambleMeanPeriod = (uint16_t)period;
        }
        else
        {
            const uint32_t tol = preambleJitterTolUs(preambleMeanPeriod);
            if (absDiffU32(period, preambleMeanPeriod) <= tol)
            {
                if (preambleGoodPeriods < 255U)
                    ++preambleGoodPeriods;
                preambleMeanPeriod =
                    (uint16_t)(((uint32_t)preambleMeanPeriod * 3U + period) / 4U);
            }
            else
            {
                preambleGoodPeriods = 1;
                preambleMeanPeriod = (uint16_t)period;
            }
        }

        if (freeFrec)
            riseSyncTime = (riseSyncTime + period / 2U) / 2U;

        if (preambleGoodPeriods >= kPreambleLockNeed)
        {
            // Новый кадр обязан стартовать с чистого state, иначе возможны CRC/sync срывы
            // при lock без промежуточного listenStart()->firstRX().
            errors.reset();
            packSize = 0;
            isBufferOverflow = false;
            isAvailable = false;
            bufBitPos = 0;
            isData = true;
            i_dataBuffer = 0;
            nextControlBit = bitPerByte;
            i_syncBit = 0;
            err_syncBit = 0;
            isWrongPack = false;
            msgTypeReceive = 0;
            memset(dataBuffer, 0x00, dataByteSizeMax);

            preambleState = PreambleState::Locked;
            isPreamb = false;
            isRecive = true;
            isReciveRaw = true;
            risePeriod = preambleMeanPeriod;
#if defined(IRDEBUG_SERIAL_PACK)
            packTraceResetFrame();
            packTraceOpen = true;
#endif
#ifdef IRDEBUG
            errPulse(up, 50);
            errPulse(down, 50);
#endif
            prevRise = front.time + preambleMeanPeriod / 2U;
            return true;
        }
        return true;
    }

    if (preambleState == PreambleState::Locked)
    {
        if (!isReciveRaw)
            preambleResetToIdle();
        return false;
    }

    return !isReciveRaw;
}

// IRDEBUG FUNC
#ifdef IRDEBUG
inline void IR_DecoderRaw::errPulse(uint8_t pin, uint8_t count)
{
    for (size_t i = 0; i < count; i++)
    {
        digitalWrite(pin, 1);
        digitalWrite(pin, 0);
    }
    digitalWrite(pin, 0);
}

inline void IR_DecoderRaw::infoPulse(uint8_t pin, uint8_t count)
{
    for (size_t i = 0; i < count; i++)
    {
        digitalWrite(pin, 1);
        digitalWrite(pin, 0);
    }
}
#endif