/*
 * Audio.h
 *
 *  Created on: Oct 28,2018
 *  Updated on: Nov 22,2022
 *      Author: Wolle (schreibfaul1)
 */

//#define SDFATFS_USED  // activate for SdFat


#pragma once
#pragma GCC optimize ("Ofast")
#include <vector>
#include <Arduino.h>
#include <libb64/cencode.h>
#include <esp32-hal-log.h>

#include <WiFi.h>
#include <WiFiClientSecure.h>
#include <vector>
#include <driver/i2s.h>

#ifndef AUDIO_NO_SD_FS
#include <SPI.h>
#ifdef SDFATFS_USED
#include <SdFat.h>  // https://github.com/greiman/SdFat
#else
#include <SD.h>
#include <SD_MMC.h>
#include <SPIFFS.h>
#include <FS.h>
#include <FFat.h>
#endif // SDFATFS_USED


#ifdef SDFATFS_USED
//typedef File32 File;
typedef FsFile File;

namespace fs {
    class FS : public SdFat {
    public:
        bool begin(SdCsPin_t csPin = SS, uint32_t maxSck = SD_SCK_MHZ(25)) { return SdFat::begin(csPin, maxSck); }
    };

    class SDFATFS : public fs::FS {
    public:
        // sdcard_type_t cardType();
        uint64_t cardSize() {
            return totalBytes();
        }
        uint64_t usedBytes() {
            // set SdFatConfig MAINTAIN_FREE_CLUSTER_COUNT non-zero. Then only the first call will take time.
            return (uint64_t)(clusterCount() - freeClusterCount()) * (uint64_t)bytesPerCluster();
        }
        uint64_t totalBytes() {
            return (uint64_t)clusterCount() * (uint64_t)bytesPerCluster();
        }
    };
}

extern fs::SDFATFS SD_SDFAT;

using namespace fs;
#define SD SD_SDFAT
#endif //SDFATFS_USED
#endif // AUDIO_NO_SD_FS

using namespace std;

extern __attribute__((weak)) void audio_info(const char *);
extern __attribute__((weak)) void audio_id3data(const char *); // ID3 metadata
#ifndef AUDIO_NO_SD_FS
extern __attribute__((weak)) void audio_id3image(File& file, const size_t pos, const size_t size); // ID3 metadata image
#endif
extern __attribute__((weak)) void audio_eof_mp3(const char*); //end of mp3 file
extern __attribute__((weak)) void audio_showstreamtitle(const char*);
extern __attribute__((weak)) void audio_showstation(const char *);
extern __attribute__((weak)) void audio_bitrate(const char*);
extern __attribute__((weak)) void audio_commercial(const char*);
extern __attribute__((weak)) void audio_icyurl(const char*);
extern __attribute__((weak)) void audio_icydescription(const char*);
extern __attribute__((weak)) void audio_lasthost(const char*);
extern __attribute__((weak)) void audio_eof_speech(const char*);
extern __attribute__((weak)) void audio_eof_stream(const char*); // The webstream comes to an end
extern __attribute__((weak)) void audio_process_extern(int16_t* buff, uint16_t len, bool *continueI2S); // record audiodata or send via BT
extern __attribute__((weak)) void audio_process_i2s(uint32_t* sample, bool *continueI2S); // record audiodata or send via BT

#define AUDIO_INFO(...) {char buff[512 + 64]; sprintf(buff,__VA_ARGS__); if(audio_info) audio_info(buff);}

//----------------------------------------------------------------------------------------------------------------------

class AudioBuffer {
// AudioBuffer will be allocated in PSRAM, If PSRAM not available or has not enough space AudioBuffer will be
// allocated in FlashRAM with reduced size
//
//  m_buffer            m_readPtr                 m_writePtr                 m_endPtr
//   |                       |<------dataLength------->|<------ writeSpace ----->|
//   ▼                       ▼                         ▼                         ▼
//   ---------------------------------------------------------------------------------------------------------------
//   |                     <--m_buffSize-->                                      |      <--m_resBuffSize -->     |
//   ---------------------------------------------------------------------------------------------------------------
//   |<-----freeSpace------->|                         |<------freeSpace-------->|
//
//
//
//   if the space between m_readPtr and buffend < m_resBuffSize copy data from the beginning to resBuff
//   so that the mp3/aac/flac frame is always completed
//
//  m_buffer                      m_writePtr                 m_readPtr        m_endPtr
//   |                                 |<-------writeSpace------>|<--dataLength-->|
//   ▼                                 ▼                         ▼                ▼
//   ---------------------------------------------------------------------------------------------------------------
//   |                        <--m_buffSize-->                                    |      <--m_resBuffSize -->     |
//   ---------------------------------------------------------------------------------------------------------------
//   |<---  ------dataLength--  ------>|<-------freeSpace------->|
//
//

public:
    AudioBuffer(size_t maxBlockSize = 0);       // constructor
    ~AudioBuffer();                             // frees the buffer
    size_t   init();                            // set default values
    bool     isInitialized() { return m_f_init; };
    void     setBufsize(int ram, int psram);
    void     changeMaxBlockSize(uint16_t mbs);  // is default 1600 for mp3 and aac, set 16384 for FLAC
    uint16_t getMaxBlockSize();                 // returns maxBlockSize
    size_t   freeSpace();                       // number of free bytes to overwrite
    size_t   writeSpace();                      // space fom writepointer to bufferend
    size_t   bufferFilled();                    // returns the number of filled bytes
    void     bytesWritten(size_t bw);           // update writepointer
    void     bytesWasRead(size_t br);           // update readpointer
    uint8_t* getWritePtr();                     // returns the current writepointer
    uint8_t* getReadPtr();                      // returns the current readpointer
    uint32_t getWritePos();                     // write position relative to the beginning
    uint32_t getReadPos();                      // read position relative to the beginning
    void     resetBuffer();                     // restore defaults
    bool     havePSRAM() { return m_f_psram; };

protected:
    size_t   m_buffSizePSRAM    = 300000;   // most webstreams limit the advance to 100...300Kbytes
    size_t   m_buffSizeRAM      = 1600 * 5;
    size_t   m_buffSize         = 0;
    size_t   m_freeSpace        = 0;
    size_t   m_writeSpace       = 0;
    size_t   m_dataLength       = 0;
    size_t   m_resBuffSizeRAM   = 1600;     // reserved buffspace, >= one mp3  frame
    size_t   m_resBuffSizePSRAM = 4096 * 4; // reserved buffspace, >= one flac frame
    size_t   m_maxBlockSize     = 1600;
    uint8_t* m_buffer           = NULL;
    uint8_t* m_writePtr         = NULL;
    uint8_t* m_readPtr          = NULL;
    uint8_t* m_endPtr           = NULL;
    bool     m_f_start          = true;
    bool     m_f_init           = false;
    bool     m_f_psram          = false;    // PSRAM is available (and used...)
};
//----------------------------------------------------------------------------------------------------------------------

class Audio : private AudioBuffer{

    AudioBuffer InBuff; // instance of input buffer

public:
    Audio(bool internalDAC = false, uint8_t channelEnabled = 3, uint8_t i2sPort = I2S_NUM_0); // #99
    ~Audio();
    void setBufsize(int rambuf_sz, int psrambuf_sz);
    bool connecttohost(const char* host, const char* user = "", const char* pwd = "");

    bool connecttospeech(const char* speech, const char* lang);
    bool connecttomarytts(const char* speech, const char* lang, const char* voice);
#ifndef AUDIO_NO_SD_FS
    bool connecttoFS(fs::FS &fs, const char* path, uint32_t resumeFilePos = 0);
    bool connecttoSD(const char* path, uint32_t resumeFilePos = 0);
#endif                           // AUDIO_NO_SD_FS
    bool setFileLoop(bool input);//TEST loop
    void setConnectionTimeout(uint16_t timeout_ms, uint16_t timeout_ms_ssl);
    bool setAudioPlayPosition(uint16_t sec);
    bool setFilePos(uint32_t pos);
    bool audioFileSeek(const float speed);
    bool setTimeOffset(int sec);
    bool setPinout(uint8_t BCLK, uint8_t LRC, uint8_t DOUT, int8_t DIN = I2S_PIN_NO_CHANGE, int8_t MCK = I2S_PIN_NO_CHANGE);
    bool pauseResume();
    bool isRunning() {return m_f_running;}
    void loop();
    uint32_t stopSong();
    void forceMono(bool m);
    void setBalance(int8_t bal = 0);
    void setVolume(uint8_t vol);
    uint8_t getVolume();
    uint8_t getI2sPort();

    uint32_t getAudioDataStartPos();
    uint32_t getFileSize();
    uint32_t getFilePos();
    uint32_t getSampleRate();
    uint8_t  getBitsPerSample();
    uint8_t  getChannels();
    uint32_t getBitRate(bool avg = false);
    uint32_t getAudioFileDuration();
    uint32_t getAudioCurrentTime();
    uint32_t getTotalPlayingTime();

    esp_err_t i2s_mclk_pin_select(const uint8_t pin);
    uint32_t inBufferFilled(); // returns the number of stored bytes in the inputbuffer
    uint32_t inBufferFree();   // returns the number of free bytes in the inputbuffer
    void setTone(int8_t gainLowPass, int8_t gainBandPass, int8_t gainHighPass);
    void setI2SCommFMT_LSB(bool commFMT);
    int getCodec() {return m_codec;}
    const char *getCodecname() {return codecname[m_codec];}

private:

    #ifndef ESP_ARDUINO_VERSION_VAL
        #define ESP_ARDUINO_VERSION_MAJOR 0
        #define ESP_ARDUINO_VERSION_MINOR 0
        #define ESP_ARDUINO_VERSION_PATCH 0
    #endif

    void UTF8toASCII(char* str);
    bool latinToUTF8(char* buff, size_t bufflen);
    void setDefaults(); // free buffers and set defaults
    void initInBuff();
    bool httpPrint(const char* host);
#ifndef AUDIO_NO_SD_FS
    void processLocalFile();
#endif // AUDIO_NO_SD_FS
    void processWebStream();
    void processWebFile();
    void processWebStreamTS();
    void processWebStreamHLS();
    void playAudioData();
    bool readPlayListData();
    const char* parsePlaylist_M3U();
    const char* parsePlaylist_PLS();
    const char* parsePlaylist_ASX();
    const char* parsePlaylist_M3U8();
    bool STfromEXTINF(char* str);
    void showCodecParams();
    int  findNextSync(uint8_t* data, size_t len);
    int  sendBytes(uint8_t* data, size_t len);
    void compute_audioCurrentTime(int bd);
    void printDecodeError(int r);
    void showID3Tag(const char* tag, const char* val);
    void unicode2utf8(char* buff, uint32_t len);
    size_t readAudioHeader(uint32_t bytes);
    int  read_WAV_Header(uint8_t* data, size_t len);
    int  read_FLAC_Header(uint8_t *data, size_t len);
    int  read_ID3_Header(uint8_t* data, size_t len);
    int  read_M4A_Header(uint8_t* data, size_t len);
    int  read_OGG_Header(uint8_t *data, size_t len);
    size_t process_m3u8_ID3_Header(uint8_t* packet);
    bool setSampleRate(uint32_t hz);
    bool setBitsPerSample(int bits);
    bool setChannels(int channels);
    bool setBitrate(int br);
    bool playChunk();
    bool playSample(int16_t sample[2]) ;
    void playI2Sremains();
    int32_t Gain(int16_t s[2]);
    bool fill_InputBuf();
    void showstreamtitle(const char* ml);
    bool parseContentType(char* ct);
    bool parseHttpResponseHeader();
    bool initializeDecoder();
    esp_err_t I2Sstart(uint8_t i2s_num);
    esp_err_t I2Sstop(uint8_t i2s_num);
    void urlencode(char* buff, uint16_t buffLen, bool spacesOnly = false);
    int16_t* IIR_filterChain0(int16_t iir_in[2], bool clear = false);
    int16_t* IIR_filterChain1(int16_t* iir_in, bool clear = false);
    int16_t* IIR_filterChain2(int16_t* iir_in, bool clear = false);
    inline void setDatamode(uint8_t dm){m_datamode=dm;}
    inline uint8_t getDatamode(){return m_datamode;}
    inline uint32_t streamavail(){ return _client ? _client->available() : 0;}
    void IIR_calculateCoefficients(int8_t G1, int8_t G2, int8_t G3);
    bool ts_parsePacket(uint8_t* packet, uint8_t* packetStart, uint8_t* packetLength);

//+++ W E B S T R E A M  -  H E L P   F U N C T I O N S +++
    uint16_t readMetadata(uint16_t b, bool first = false);
    size_t   chunkedDataTransfer(uint8_t* bytes);
    bool     readID3V1Tag();
    void     slowStreamDetection(uint32_t inBuffFilled, uint32_t maxFrameSize);
    void     lostStreamDetection(uint32_t bytesAvail);
#ifndef AUDIO_NO_SD_FS
    void     seek_m4a_stsz();
    uint32_t m4a_correctResumeFilePos(uint32_t resumeFilePos);
    uint32_t flac_correctResumeFilePos(uint32_t resumeFilePos);
    uint32_t mp3_correctResumeFilePos(uint32_t resumeFilePos);
#endif // AUDIO_NO_SD_FS

    //++++ implement several function with respect to the index of string ++++
    void trim(char *s) {
    //fb   trim in place
        char *pe;
        char *p = s;
        while ( isspace(*p) ) p++; //left
        pe = p; //right
        while ( *pe != '\0' ) pe++;
        do {
            pe--;
        } while ( (pe > p) && isspace(*pe) );
        if (p == s) {
            *++pe = '\0';
        } else {  //move
            while ( p <= pe ) *s++ = *p++;
            *s = '\0';
        }
    }

    bool startsWith (const char* base, const char* str) {
    //fb
        char c;
        while ( (c = *str++) != '\0' )
          if (c != *base++) return false;
        return true;
    }

    bool endsWith (const char* base, const char* str) {
    //fb
        int slen = strlen(str) - 1;
        const char *p = base + strlen(base) - 1;
        while(p > base && isspace(*p)) p--;  // rtrim
        p -= slen;
        if (p < base) return false;
        return (strncmp(p, str, slen) == 0);
    }

    int indexOf (const char* base, const char* str, int startIndex = 0) {
    //fb
        const char *p = base;
        for (; startIndex > 0; startIndex--)
            if (*p++ == '\0') return -1;
        char* pos = strstr(p, str);
        if (pos == nullptr) return -1;
        return pos - base;
    }

    int indexOf (const char* base, char ch, int startIndex = 0) {
    //fb
        const char *p = base;
        for (; startIndex > 0; startIndex--)
            if (*p++ == '\0') return -1;
        char *pos = strchr(p, ch);
        if (pos == nullptr) return -1;
        return pos - base;
    }

    int lastIndexOf(const char* haystack, const char* needle) {
    //fb
        int nlen = strlen(needle);
        if (nlen == 0) return -1;
        const char *p = haystack - nlen + strlen(haystack);
        while (p >= haystack) {
          int i = 0;
          while (needle[i] == p[i])
            if (++i == nlen) return p - haystack;
          p--;
        }
        return -1;
    }

    int lastIndexOf(const char* haystack, const char needle) {
    //fb
        const char *p = strrchr(haystack, needle);
        return (p ? p - haystack : -1);
    }

    int specialIndexOf (uint8_t* base, const char* str, int baselen, bool exact = false){
        int result;  // seek for str in buffer or in header up to baselen, not nullterninated
        if (strlen(str) > baselen) return -1; // if exact == true seekstr in buffer must have "\0" at the end
        for (int i = 0; i < baselen - strlen(str); i++){
            result = i;
            for (int j = 0; j < strlen(str) + exact; j++){
                if (*(base + i + j) != *(str + j)){
                    result = -1;
                    break;
                }
            }
            if (result >= 0) break;
        }
        return result;
    }

    // some other functions
    size_t bigEndian(uint8_t* base, uint8_t numBytes, uint8_t shiftLeft = 8){
        uint64_t result = 0;
        if(numBytes < 1 || numBytes > 8) return 0;
        for (int i = 0; i < numBytes; i++) {
                result += *(base + i) << (numBytes -i - 1) * shiftLeft;
        }
        if(result > SIZE_MAX) {log_e("range overflow"); result = 0;} // overflow
        return (size_t)result;
    }

    bool b64encode(const char* source, uint16_t sourceLength, char* dest){
        size_t size = base64_encode_expected_len(sourceLength) + 1;
        char * buffer = (char *) malloc(size);
        if(buffer) {
            base64_encodestate _state;
            base64_init_encodestate(&_state);
            int len = base64_encode_block(&source[0], sourceLength, &buffer[0], &_state);
            len = base64_encode_blockend((buffer + len), &_state);
            memcpy(dest, buffer, strlen(buffer));
            dest[strlen(buffer)] = '\0';
            free(buffer);
            return true;
        }
        return false;
    }
    size_t urlencode_expected_len(const char* source){
        size_t expectedLen = strlen(source);
        for(int i = 0; i < strlen(source); i++) {
            if(isalnum(source[i])){;}
            else expectedLen += 2;
        }
        return expectedLen;
    }
    void vector_clear_and_shrink(vector<char*>&vec){
        uint size = vec.size();
        for (int i = 0; i < size; i++) {
            if(vec[i]){
                free(vec[i]);
                vec[i] = NULL;
            }
        }
        vec.clear();
        vec.shrink_to_fit();
    }
    uint32_t simpleHash(const char* str){
        if(str == NULL) return 0;
        uint32_t hash = 0;
        for(int i=0; i<strlen(str); i++){
		    if(str[i] < 32) continue; // ignore control sign
		    hash += (str[i] - 31) * i * 32;
        }
        return hash;
	}

private:
    const char *codecname[9] = {"unknown", "WAV", "MP3", "AAC", "M4A", "FLAC", "OGG", "OGG FLAC", "OPUS"};
    enum : int { APLL_AUTO = -1, APLL_ENABLE = 1, APLL_DISABLE = 0 };
    enum : int { EXTERNAL_I2S = 0, INTERNAL_DAC = 1, INTERNAL_PDM = 2 };
    enum : int { FORMAT_NONE = 0, FORMAT_M3U = 1, FORMAT_PLS = 2, FORMAT_ASX = 3, FORMAT_M3U8 = 4};
    enum : int { AUDIO_NONE, HTTP_RESPONSE_HEADER, AUDIO_DATA, AUDIO_LOCALFILE,
                 AUDIO_PLAYLISTINIT, AUDIO_PLAYLISTHEADER,  AUDIO_PLAYLISTDATA};
    enum : int { FLAC_BEGIN = 0, FLAC_MAGIC = 1, FLAC_MBH =2, FLAC_SINFO = 3, FLAC_PADDING = 4, FLAC_APP = 5,
                 FLAC_SEEK = 6, FLAC_VORBIS = 7, FLAC_CUESHEET = 8, FLAC_PICTURE = 9, FLAC_OKAY = 100};
    enum : int { M4A_BEGIN = 0, M4A_FTYP = 1, M4A_CHK = 2, M4A_MOOV = 3, M4A_FREE = 4, M4A_TRAK = 5, M4A_MDAT = 6,
                 M4A_ILST = 7, M4A_MP4A = 8, M4A_AMRDY = 99, M4A_OKAY = 100};
    enum : int { OGG_BEGIN = 0, OGG_MAGIC = 1, OGG_HEADER = 2, OGG_FIRST = 3, OGG_AMRDY = 99, OGG_OKAY = 100};
    enum : int { CODEC_NONE = 0, CODEC_WAV = 1, CODEC_MP3 = 2, CODEC_AAC = 3, CODEC_M4A = 4, CODEC_FLAC = 5,
                 CODEC_OGG = 6, CODEC_OGG_FLAC = 7, CODEC_OGG_OPUS = 8, CODEC_AACP = 9};
    enum : int { ST_NONE = 0, ST_WEBFILE = 1, ST_WEBSTREAM = 2};
    typedef enum { LEFTCHANNEL=0, RIGHTCHANNEL=1 } SampleIndex;
    typedef enum { LOWSHELF = 0, PEAKEQ = 1, HIFGSHELF =2 } FilterType;

    const uint8_t volumetable[22]={   0,  1,  2,  3,  4 , 6 , 8, 10, 12, 14, 17,
                                     20, 23, 27, 30 ,34, 38, 43 ,48, 52, 58, 64}; //22 elements

    typedef struct _filter{
        float a0;
        float a1;
        float a2;
        float b1;
        float b2;
    } filter_t;

    typedef struct _pis_array{
        int number;
        int pids[4];
    } pid_array;

#ifndef AUDIO_NO_SD_FS
    File                  audiofile;    // @suppress("Abstract class cannot be instantiated")
#endif  // AUDIO_NO_SD_FS
    WiFiClient            client;       // @suppress("Abstract class cannot be instantiated")
    WiFiClientSecure      clientsecure; // @suppress("Abstract class cannot be instantiated")
    WiFiClient*           _client = nullptr;
    i2s_config_t          m_i2s_config = {}; // stores values for I2S driver
    i2s_pin_config_t      m_pin_config = {};
    std::vector<char*>    m_playlistContent; // m3u8 playlist buffer
    std::vector<char*>    m_playlistURL;     // m3u8 streamURLs buffer
    std::vector<uint32_t> m_hashQueue;

    const size_t    m_frameSizeWav  = 1024;
    const size_t    m_frameSizeMP3  = 1600;
    const size_t    m_frameSizeAAC  = 1600;
    const size_t    m_frameSizeFLAC = 4096 * 4;

    static const uint8_t m_tsPacketSize  = 188;
    static const uint8_t m_tsHeaderSize  = 4;

    char*           m_chbuf = NULL;
    uint16_t        m_chbufSize = 0;                // will set in constructor (depending on PSRAM)
    char            m_lastHost[512];                // Store the last URL to a webstream
    char*           m_playlistBuff = NULL;          // stores playlistdata
    const uint16_t  m_plsBuffEntryLen = 256;        // length of each entry in playlistBuff
    filter_t        m_filter[3];                    // digital filters
    int             m_LFcount = 0;                  // Detection of end of header
    uint32_t        m_sampleRate=16000;
    uint32_t        m_bitRate=0;                    // current bitrate given fom decoder
    uint32_t        m_avr_bitrate = 0;              // average bitrate, median computed by VBR
    int             m_readbytes = 0;                // bytes read
    uint32_t        m_metacount = 0;                // counts down bytes between metadata
    int             m_controlCounter = 0;           // Status within readID3data() and readWaveHeader()
    int8_t          m_balance = 0;                  // -16 (mute left) ... +16 (mute right)
    uint8_t         m_vol=64;                       // volume
    uint8_t         m_bitsPerSample = 16;           // bitsPerSample
    uint8_t         m_channels = 2;
    uint8_t         m_i2s_num = I2S_NUM_0;          // I2S_NUM_0 or I2S_NUM_1
    uint8_t         m_playlistFormat = 0;           // M3U, PLS, ASX
    uint8_t         m_codec = CODEC_NONE;           //
    uint8_t         m_expectedCodec = CODEC_NONE;   // set in connecttohost (e.g. http://url.mp3 -> CODEC_MP3)
    uint8_t         m_expectedPlsFmt = FORMAT_NONE; // set in connecttohost (e.g. streaming01.m3u) -> FORMAT_M3U)
    uint8_t         m_filterType[2];                // lowpass, highpass
    uint8_t         m_streamType = ST_NONE;
    uint8_t         m_ID3Size = 0;                  // lengt of ID3frame - ID3header
    int16_t         m_outBuff[2048*2];              // Interleaved L/R
    int16_t         m_validSamples = 0;
    int16_t         m_curSample = 0;
    uint16_t        m_datamode = 0;                 // Statemaschine
    uint16_t        m_streamTitleHash = 0;          // remember streamtitle, ignore multiple occurence in metadata
    uint16_t        m_timeout_ms = 250;
    uint16_t        m_timeout_ms_ssl = 2700;
    uint8_t         m_flacBitsPerSample = 0;        // bps should be 16
    uint8_t         m_flacNumChannels = 0;          // can be read out in the FLAC file header
    uint32_t        m_flacSampleRate = 0;           // can be read out in the FLAC file header
    uint16_t        m_flacMaxFrameSize = 0;         // can be read out in the FLAC file header
    uint16_t        m_flacMaxBlockSize = 0;         // can be read out in the FLAC file header
    uint32_t        m_flacTotalSamplesInStream = 0; // can be read out in the FLAC file header
    uint32_t        m_metaint = 0;                  // Number of databytes between metadata
    uint32_t        m_chunkcount = 0 ;              // Counter for chunked transfer
    uint32_t        m_t0 = 0;                       // store millis(), is needed for a small delay
    uint32_t        m_contentlength = 0;            // Stores the length if the stream comes from fileserver
    uint32_t        m_bytesNotDecoded = 0;          // pictures or something else that comes with the stream
    uint32_t        m_PlayingStartTime = 0;         // Stores the milliseconds after the start of the audio
    uint32_t        m_resumeFilePos = 0;            // the return value from stopSong() can be entered here
    uint16_t        m_m3u8_targetDuration = 10;     //
    uint32_t        m_stsz_numEntries = 0;          // num of entries inside stsz atom (uint32_t)
    uint32_t        m_stsz_position = 0;            // pos of stsz atom within file
    bool            m_f_metadata = false;           // assume stream without metadata
    bool            m_f_unsync = false;             // set within ID3 tag but not used
    bool            m_f_exthdr = false;             // ID3 extended header
    bool            m_f_ssl = false;
    bool            m_f_running = false;
    bool            m_f_firstCall = false;          // InitSequence for processWebstream and processLokalFile
    bool            m_f_chunked = false ;           // Station provides chunked transfer
    bool            m_f_firstmetabyte = false;      // True if first metabyte (counter)
    bool            m_f_playing = false;            // valid mp3 stream recognized
    bool            m_f_tts = false;                // text to speech
    bool            m_f_loop = false;               // Set if audio file should loop
    bool            m_f_forceMono = false;          // if true stereo -> mono
    bool            m_f_internalDAC = false;        // false: output vis I2S, true output via internal DAC
    bool            m_f_rtsp = false;               // set if RTSP is used (m3u8 stream)
    bool            m_f_m3u8data = false;           // used in processM3U8entries
    bool            m_f_Log = false;                // set in platformio.ini  -DAUDIO_LOG and -DCORE_DEBUG_LEVEL=3 or 4
    bool            m_f_continue = false;           // next m3u8 chunk is available
    bool            m_f_ts = true;                  // transport stream
    uint8_t         m_f_channelEnabled = 3;         // internal DAC, both channels
    uint32_t        m_audioFileDuration = 0;
    float           m_audioCurrentTime = 0;
    uint32_t        m_audioDataStart = 0;           // in bytes
    size_t          m_audioDataSize = 0;            //
    float           m_filterBuff[3][2][2][2];       // IIR filters memory for Audio DSP
    size_t          m_i2s_bytesWritten = 0;         // set in i2s_write() but not used
    size_t          m_file_size = 0;                // size of the file
    uint16_t        m_filterFrequency[2];
    int8_t          m_gain0 = 0;                    // cut or boost filters (EQ)
    int8_t          m_gain1 = 0;
    int8_t          m_gain2 = 0;

    pid_array       m_pidsOfPMT;
    int16_t         m_pidOfAAC;
    uint8_t         m_packetBuff[m_tsPacketSize];
    int16_t         m_pesDataLength = 0;
};

//----------------------------------------------------------------------------------------------------------------------
