/*
 * flac_decoder.h
 *
 * Created on: Jul 03,2020
 * Updated on: Mar 28,2024
 *
 *      Author: wolle
 *
 *  Restrictions:
 *  blocksize must not exceed 16342 bytes
 *  bits per sample must be 8 or 16
 *  num Channels must be 1 or 2
 *
 *
 */
#pragma once
#pragma GCC optimize ("Ofast")

#include "Arduino.h"
#include <vector>
using namespace std;

#define MAX_CHANNELS 2
#define MAX_BLOCKSIZE 8192

enum : uint8_t {FLACDECODER_INIT, FLACDECODER_READ_IN, FLACDECODER_WRITE_OUT};
enum : uint8_t {DECODE_FRAME, DECODE_SUBFRAMES, OUT_SAMPLES};
enum : int8_t  {FLAC_PARSE_OGG_DONE = 100,
                FLAC_DECODE_FRAMES_LOOP = 100,
                GIVE_NEXT_LOOP = +1,
                ERR_FLAC_NONE = 0,
                ERR_FLAC_BLOCKSIZE_TOO_BIG = -1,
                ERR_FLAC_RESERVED_BLOCKSIZE_UNSUPPORTED = -2,
                ERR_FLAC_SYNC_CODE_NOT_FOUND = -3,
                ERR_FLAC_UNKNOWN_CHANNEL_ASSIGNMENT = -4,
                ERR_FLAC_RESERVED_CHANNEL_ASSIGNMENT = -5,
                ERR_FLAC_RESERVED_SUB_TYPE = -6,
                ERR_FLAC_PREORDER_TOO_BIG = -7,
                ERR_FLAC_RESERVED_RESIDUAL_CODING = -8,
                ERR_FLAC_WRONG_RICE_PARTITION_NR = -9,
                ERR_FLAC_BITS_PER_SAMPLE_TOO_BIG = -10,
                ERR_FLAG_BITS_PER_SAMPLE_UNKNOWN = -11,
                ERR_FLAC_DECODER_ASYNC = -12,
                ERR_FLAC_UNIMPLEMENTED = -13};

typedef struct FLACMetadataBlock_t{
                              // METADATA_BLOCK_STREAMINFO
    uint16_t minblocksize;    // The minimum block size (in samples) used in the stream.
                              //----------------------------------------------------------------------------------------
                              // The maximum block size (in samples) used in the stream.
    uint16_t maxblocksize;    // (Minimum blocksize == maximum blocksize) implies a fixed-blocksize stream.
                              //----------------------------------------------------------------------------------------
                              // The minimum frame size (in bytes) used in the stream.
    uint32_t minframesize;    // May be 0 to imply the value is not known.
                              //----------------------------------------------------------------------------------------
                              // The maximum frame size (in bytes) used in the stream.
    uint32_t maxframesize;    // May be 0 to imply the value is not known.
                              //----------------------------------------------------------------------------------------
                              // Sample rate in Hz. Though 20 bits are available,
                              // the maximum sample rate is limited by the structure of frame headers to 655350Hz.
    uint32_t sampleRate;      // Also, a value of 0 is invalid.
                              //----------------------------------------------------------------------------------------
                              // Number of channels FLAC supports from 1 to 8 channels
    uint8_t  numChannels;     // 000 : 1 channel .... 111 : 8 channels
                              //----------------------------------------------------------------------------------------
                              // Sample size in bits:
                              // 000 : get from STREAMINFO metadata block
                              // 001 : 8 bits per sample
                              // 010 : 12 bits per sample
                              // 011 : reserved
                              // 100 : 16 bits per sample
                              // 101 : 20 bits per sample
                              // 110 : 24 bits per sample
     uint8_t  bitsPerSample;  // 111 : reserved
                              //----------------------------------------------------------------------------------------
                              // Total samples in stream. 'Samples' means inter-channel sample,
                              // i.e. one second of 44.1Khz audio will have 44100 samples regardless of the number
     uint64_t totalSamples;   // of channels. A value of zero here means the number of total samples is unknown.
                              //----------------------------------------------------------------------------------------
     uint32_t audioDataLength;// is not the filelength, is only the length of the audio datablock in bytes



}FLACMetadataBlock_t;


typedef struct FLACFrameHeader_t {
                              // 0 : fixed-blocksize stream; frame header encodes the frame number
    uint8_t blockingStrategy; // 1 : variable-blocksize stream; frame header encodes the sample number
                              //----------------------------------------------------------------------------------------
                              // Block size in inter-channel samples:
                              // 0000 : reserved
                              // 0001 : 192 samples
                              // 0010-0101 : 576 * (2^(n-2)) samples, i.e. 576/1152/2304/4608
                              // 0110 : get 8 bit (blocksize-1) from end of header
                              // 0111 : get 16 bit (blocksize-1) from end of header
    uint8_t blockSizeCode;    // 1000-1111 : 256 * (2^(n-8)) samples, i.e. 256/512/1024/2048/4096/8192/16384/32768
                              //----------------------------------------------------------------------------------------
                              // 0000 : get from STREAMINFO metadata block
                              // 0001 : 88.2kHz
                              // 0010 : 176.4kHz
                              // 0011 : 192kHz
                              // 0100 : 8kHz
                              // 0101 : 16kHz
                              // 0110 : 22.05kHz
                              // 0111 : 24kHz
                              // 1000 : 32kHz
                              // 1001 : 44.1kHz
                              // 1010 : 48kHz
                              // 1011 : 96kHz
                              // 1100 : get 8 bit sample rate (in kHz) from end of header
                              // 1101 : get 16 bit sample rate (in Hz) from end of header
                              // 1110 : get 16 bit sample rate (in tens of Hz) from end of header
    uint8_t sampleRateCode;   // 1111 : invalid, to prevent sync-fooling string of 1s
                              //----------------------------------------------------------------------------------------
                              // Channel assignment
                              // 0000 1 channel: mono
                              // 0001 2 channels: left, right
                              // 0010 3 channels
                              // 0011 4 channels
                              // 0100 5 channels
                              // 0101 6 channels
                              // 0110 7 channels
                              // 0111 8 channels
                              // 1000 : left/side stereo: channel 0 is the left channel, channel 1 is the side(difference) channel
                              // 1001 : right/side stereo: channel 0 is the side(difference) channel, channel 1 is the right channel
                              // 1010 : mid/side stereo: channel 0 is the mid(average) channel, channel 1 is the side(difference) channel
    uint8_t chanAsgn;         // 1011-1111 : reserved
                              //----------------------------------------------------------------------------------------
                              // Sample size in bits:
                              // 000 : get from STREAMINFO metadata block
                              // 001 : 8 bits per sample
                              // 010 : 12 bits per sample
                              // 011 : reserved
                              // 100 : 16 bits per sample
                              // 101 : 20 bits per sample
                              // 110 : 24 bits per sample
    uint8_t sampleSizeCode;   // 111 : reserved
                              //----------------------------------------------------------------------------------------
    uint32_t totalSamples;    // totalSamplesInStream
                              //----------------------------------------------------------------------------------------
    uint32_t bitrate;         // bitrate


}FLACFrameHeader_t;

int              FLACFindSyncWord(unsigned char* buf, int nBytes);
boolean          FLACFindMagicWord(unsigned char* buf, int nBytes);
char*            FLACgetStreamTitle();
int              FLACparseOGG(uint8_t* inbuf, int* bytesLeft);
vector<uint32_t> FLACgetMetadataBlockPicture();
int              parseFlacFirstPacket(uint8_t* inbuf, int16_t nBytes);
int              parseMetaDataBlockHeader(uint8_t* inbuf, int16_t nBytes);
bool             FLACDecoder_AllocateBuffers(void);
void             FLACDecoder_setDefaults();
void             FLACDecoder_ClearBuffer();
void             FLACDecoder_FreeBuffers();
void             FLACSetRawBlockParams(uint8_t Chans, uint32_t SampRate, uint8_t BPS, uint32_t tsis, uint32_t AuDaLength);
void             FLACDecoderReset();
int8_t           FLACDecode(uint8_t* inbuf, int* bytesLeft, short* outbuf);
int8_t           FLACDecodeNative(uint8_t* inbuf, int* bytesLeft, short* outbuf);
int8_t           flacDecodeFrame(uint8_t* inbuf, int* bytesLeft);
uint16_t         FLACGetOutputSamps();
uint64_t         FLACGetTotoalSamplesInStream();
uint8_t          FLACGetBitsPerSample();
uint8_t          FLACGetChannels();
uint32_t         FLACGetSampRate();
uint32_t         FLACGetBitRate();
uint32_t         FLACGetAudioFileDuration();
uint32_t         readUint(uint8_t nBits, int* bytesLeft);
int32_t          readSignedInt(int nBits, int* bytesLeft);
int64_t          readRiceSignedInt(uint8_t param, int* bytesLeft);
void             alignToByte();
int8_t           decodeSubframes(int* bytesLeft);
int8_t           decodeSubframe(uint8_t sampleDepth, uint8_t ch, int* bytesLeft);
int8_t           decodeFixedPredictionSubframe(uint8_t predOrder, uint8_t sampleDepth, uint8_t ch, int* bytesLeft);
int8_t           decodeLinearPredictiveCodingSubframe(int lpcOrder, int sampleDepth, uint8_t ch, int* bytesLeft);
int8_t           decodeResiduals(uint8_t warmup, uint8_t ch, int* bytesLeft);
void             restoreLinearPrediction(uint8_t ch, uint8_t shift);
int              FLAC_specialIndexOf(uint8_t* base, const char* str, int baselen, bool exact = false);
char*            flac_x_ps_malloc(uint16_t len);
char*            flac_x_ps_calloc(uint16_t len, uint8_t size);
char*            flac_x_ps_strdup(const char* str);
char*            flac_x_ps_strndup(const char* str, uint16_t n);
