/*
  ==============================================================================

   This file is part of the JUCE 6 technical preview.
   Copyright (c) 2020 - Raw Material Software Limited

   You may use this code under the terms of the GPL v3
   (see www.gnu.org/licenses).

   For this technical preview, this file is not subject to commercial licensing.

   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
   DISCLAIMED.

  ==============================================================================
*/

namespace juce
{

#if JUCE_USE_FLAC

}

#if defined _WIN32 && !defined __CYGWIN__
 #include <io.h>
#else
 #include <unistd.h>
#endif

#if defined _MSC_VER || defined __BORLANDC__ || defined __MINGW32__
 #include <sys/types.h> /* for off_t */
#endif

#if HAVE_INTTYPES_H
 #define __STDC_FORMAT_MACROS
 #include <inttypes.h>
#endif

#if defined _MSC_VER || defined __MINGW32__ || defined __CYGWIN__ || defined __EMX__
 #include <io.h> /* for _setmode(), chmod() */
 #include <fcntl.h> /* for _O_BINARY */
#else
 #include <unistd.h> /* for chown(), unlink() */
#endif

#if defined _MSC_VER || defined __BORLANDC__ || defined __MINGW32__
 #if defined __BORLANDC__
  #include <utime.h> /* for utime() */
 #else
  #include <sys/utime.h> /* for utime() */
 #endif
#else
 #include <sys/types.h> /* some flavors of BSD (like OS X) require this to get time_t */
 #include <utime.h> /* for utime() */
#endif

#if defined _MSC_VER
 #if _MSC_VER >= 1600
  #include <stdint.h>
 #else
  #include <limits.h>
 #endif
#endif

#ifdef _WIN32
 #include <stdio.h>
 #include <sys/stat.h>
 #include <stdarg.h>
 #include <windows.h>
#endif

#ifdef DEBUG
 #include <assert.h>
#endif

#include <stdlib.h>
#include <stdio.h>

namespace juce
{

namespace FlacNamespace
{
#if JUCE_INCLUDE_FLAC_CODE || ! defined (JUCE_INCLUDE_FLAC_CODE)

 #undef VERSION
 #define VERSION "1.3.1"

 #define FLAC__NO_DLL 1

 JUCE_BEGIN_IGNORE_WARNINGS_MSVC (4267 4127 4244 4996 4100 4701 4702 4013 4133 4206 4312 4505 4365 4005 4334 181 111)
 #if ! JUCE_MSVC
  #define HAVE_LROUND 1
 #endif

 #if JUCE_MAC
  #define FLAC__SYS_DARWIN 1
 #endif

 #ifndef SIZE_MAX
  #define SIZE_MAX 0xffffffff
 #endif

 JUCE_BEGIN_IGNORE_WARNINGS_GCC_LIKE ("-Wconversion",
                                      "-Wshadow",
                                      "-Wdeprecated-register",
                                      "-Wswitch-enum",
                                      "-Wswitch-default",
                                      "-Wimplicit-fallthrough",
                                      "-Wzero-as-null-pointer-constant",
                                      "-Wsign-conversion",
                                      "-Wredundant-decls")

 #if JUCE_INTEL
  #if JUCE_32BIT
   #define FLAC__CPU_IA32 1
  #endif
  #if JUCE_64BIT
   #define FLAC__CPU_X86_64 1
  #endif
  #define FLAC__HAS_X86INTRIN 1
 #endif

 #undef __STDC_LIMIT_MACROS
 #define __STDC_LIMIT_MACROS 1
 #define flac_max jmax
 #define flac_min jmin
 #undef DEBUG // (some flac code dumps debug trace if the app defines this macro)
 #include "flac/all.h"
 #include "flac/libFLAC/bitmath.c"
 #include "flac/libFLAC/bitreader.c"
 #include "flac/libFLAC/bitwriter.c"
 #include "flac/libFLAC/cpu.c"
 #include "flac/libFLAC/crc.c"
 #include "flac/libFLAC/fixed.c"
 #include "flac/libFLAC/float.c"
 #include "flac/libFLAC/format.c"
 #include "flac/libFLAC/lpc_flac.c"
 #include "flac/libFLAC/md5.c"
 #include "flac/libFLAC/memory.c"
 #include "flac/libFLAC/stream_decoder.c"
 #include "flac/libFLAC/stream_encoder.c"
 #include "flac/libFLAC/stream_encoder_framing.c"
 #include "flac/libFLAC/window_flac.c"
 #undef VERSION
#else
 #include <FLAC/all.h>
#endif

 JUCE_END_IGNORE_WARNINGS_GCC_LIKE
 JUCE_END_IGNORE_WARNINGS_MSVC
}

#undef max
#undef min

//==============================================================================
static const char* const flacFormatName = "FLAC file";


//==============================================================================
class FlacReader  : public AudioFormatReader
{
public:
    FlacReader (InputStream* in)  : AudioFormatReader (in, flacFormatName)
    {
        lengthInSamples = 0;
        decoder = FlacNamespace::FLAC__stream_decoder_new();

        ok = FLAC__stream_decoder_init_stream (decoder,
                                               readCallback_, seekCallback_, tellCallback_, lengthCallback_,
                                               eofCallback_, writeCallback_, metadataCallback_, errorCallback_,
                                               this) == FlacNamespace::FLAC__STREAM_DECODER_INIT_STATUS_OK;

        if (ok)
        {
            FLAC__stream_decoder_process_until_end_of_metadata (decoder);

            if (lengthInSamples == 0 && sampleRate > 0)
            {
                // the length hasn't been stored in the metadata, so we'll need to
                // work it out the length the hard way, by scanning the whole file..
                scanningForLength = true;
                FLAC__stream_decoder_process_until_end_of_stream (decoder);
                scanningForLength = false;
                auto tempLength = lengthInSamples;

                FLAC__stream_decoder_reset (decoder);
                FLAC__stream_decoder_process_until_end_of_metadata (decoder);
                lengthInSamples = tempLength;
            }
        }
    }

    ~FlacReader() override
    {
        FlacNamespace::FLAC__stream_decoder_delete (decoder);
    }

    void useMetadata (const FlacNamespace::FLAC__StreamMetadata_StreamInfo& info)
    {
        sampleRate = info.sample_rate;
        bitsPerSample = info.bits_per_sample;
        lengthInSamples = (unsigned int) info.total_samples;
        numChannels = info.channels;

        reservoir.setSize ((int) numChannels, 2 * (int) info.max_blocksize, false, false, true);
    }

    // returns the number of samples read
    bool readSamples (int** destSamples, int numDestChannels, int startOffsetInDestBuffer,
                      int64 startSampleInFile, int numSamples) override
    {
        if (! ok)
            return false;

        while (numSamples > 0)
        {
            if (startSampleInFile >= reservoirStart
                 && startSampleInFile < reservoirStart + samplesInReservoir)
            {
                auto num = (int) jmin ((int64) numSamples,
                                       reservoirStart + samplesInReservoir - startSampleInFile);

                jassert (num > 0);

                for (int i = jmin (numDestChannels, reservoir.getNumChannels()); --i >= 0;)
                    if (destSamples[i] != nullptr)
                        memcpy (destSamples[i] + startOffsetInDestBuffer,
                                reservoir.getReadPointer (i, (int) (startSampleInFile - reservoirStart)),
                                (size_t) num * sizeof (int));

                startOffsetInDestBuffer += num;
                startSampleInFile += num;
                numSamples -= num;
            }
            else
            {
                if (startSampleInFile >= lengthInSamples)
                {
                    samplesInReservoir = 0;
                }
                else if (startSampleInFile < reservoirStart
                          || startSampleInFile > reservoirStart + jmax (samplesInReservoir, 511))
                {
                    // had some problems with flac crashing if the read pos is aligned more
                    // accurately than this. Probably fixed in newer versions of the library, though.
                    reservoirStart = (int) (startSampleInFile & ~511);
                    samplesInReservoir = 0;
                    FLAC__stream_decoder_seek_absolute (decoder, (FlacNamespace::FLAC__uint64) reservoirStart);
                }
                else
                {
                    reservoirStart += samplesInReservoir;
                    samplesInReservoir = 0;
                    FLAC__stream_decoder_process_single (decoder);
                }

                if (samplesInReservoir == 0)
                    break;
            }
        }

        if (numSamples > 0)
        {
            for (int i = numDestChannels; --i >= 0;)
                if (destSamples[i] != nullptr)
                    zeromem (destSamples[i] + startOffsetInDestBuffer, (size_t) numSamples * sizeof (int));
        }

        return true;
    }

    void useSamples (const FlacNamespace::FLAC__int32* const buffer[], int numSamples)
    {
        if (scanningForLength)
        {
            lengthInSamples += numSamples;
        }
        else
        {
            if (numSamples > reservoir.getNumSamples())
                reservoir.setSize ((int) numChannels, numSamples, false, false, true);

            auto bitsToShift = 32 - bitsPerSample;

            for (int i = 0; i < (int) numChannels; ++i)
            {
                auto* src = buffer[i];
                int n = i;

                while (src == nullptr && n > 0)
                    src = buffer [--n];

                if (src != nullptr)
                {
                    auto* dest = reinterpret_cast<int*> (reservoir.getWritePointer(i));

                    for (int j = 0; j < numSamples; ++j)
                        dest[j] = src[j] << bitsToShift;
                }
            }

            samplesInReservoir = numSamples;
        }
    }

    //==============================================================================
    static FlacNamespace::FLAC__StreamDecoderReadStatus readCallback_ (const FlacNamespace::FLAC__StreamDecoder*, FlacNamespace::FLAC__byte buffer[], size_t* bytes, void* client_data)
    {
        *bytes = (size_t) static_cast<const FlacReader*> (client_data)->input->read (buffer, (int) *bytes);
        return FlacNamespace::FLAC__STREAM_DECODER_READ_STATUS_CONTINUE;
    }

    static FlacNamespace::FLAC__StreamDecoderSeekStatus seekCallback_ (const FlacNamespace::FLAC__StreamDecoder*, FlacNamespace::FLAC__uint64 absolute_byte_offset, void* client_data)
    {
        static_cast<const FlacReader*> (client_data)->input->setPosition ((int) absolute_byte_offset);
        return FlacNamespace::FLAC__STREAM_DECODER_SEEK_STATUS_OK;
    }

    static FlacNamespace::FLAC__StreamDecoderTellStatus tellCallback_ (const FlacNamespace::FLAC__StreamDecoder*, FlacNamespace::FLAC__uint64* absolute_byte_offset, void* client_data)
    {
        *absolute_byte_offset = (uint64) static_cast<const FlacReader*> (client_data)->input->getPosition();
        return FlacNamespace::FLAC__STREAM_DECODER_TELL_STATUS_OK;
    }

    static FlacNamespace::FLAC__StreamDecoderLengthStatus lengthCallback_ (const FlacNamespace::FLAC__StreamDecoder*, FlacNamespace::FLAC__uint64* stream_length, void* client_data)
    {
        *stream_length = (uint64) static_cast<const FlacReader*> (client_data)->input->getTotalLength();
        return FlacNamespace::FLAC__STREAM_DECODER_LENGTH_STATUS_OK;
    }

    static FlacNamespace::FLAC__bool eofCallback_ (const FlacNamespace::FLAC__StreamDecoder*, void* client_data)
    {
        return static_cast<const FlacReader*> (client_data)->input->isExhausted();
    }

    static FlacNamespace::FLAC__StreamDecoderWriteStatus writeCallback_ (const FlacNamespace::FLAC__StreamDecoder*,
                                                                         const FlacNamespace::FLAC__Frame* frame,
                                                                         const FlacNamespace::FLAC__int32* const buffer[],
                                                                         void* client_data)
    {
        static_cast<FlacReader*> (client_data)->useSamples (buffer, (int) frame->header.blocksize);
        return FlacNamespace::FLAC__STREAM_DECODER_WRITE_STATUS_CONTINUE;
    }

    static void metadataCallback_ (const FlacNamespace::FLAC__StreamDecoder*,
                                   const FlacNamespace::FLAC__StreamMetadata* metadata,
                                   void* client_data)
    {
        static_cast<FlacReader*> (client_data)->useMetadata (metadata->data.stream_info);
    }

    static void errorCallback_ (const FlacNamespace::FLAC__StreamDecoder*, FlacNamespace::FLAC__StreamDecoderErrorStatus, void*)
    {
    }

private:
    FlacNamespace::FLAC__StreamDecoder* decoder;
    AudioBuffer<float> reservoir;
    int reservoirStart = 0, samplesInReservoir = 0;
    bool ok = false, scanningForLength = false;

    JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (FlacReader)
};


//==============================================================================
class FlacWriter  : public AudioFormatWriter
{
public:
    FlacWriter (OutputStream* out, double rate, uint32 numChans, uint32 bits, int qualityOptionIndex)
        : AudioFormatWriter (out, flacFormatName, rate, numChans, bits),
          streamStartPos (output != nullptr ? jmax (output->getPosition(), 0ll) : 0ll)
    {
        encoder = FlacNamespace::FLAC__stream_encoder_new();

        if (qualityOptionIndex > 0)
            FLAC__stream_encoder_set_compression_level (encoder, (uint32) jmin (8, qualityOptionIndex));

        FLAC__stream_encoder_set_do_mid_side_stereo (encoder, numChannels == 2);
        FLAC__stream_encoder_set_loose_mid_side_stereo (encoder, numChannels == 2);
        FLAC__stream_encoder_set_channels (encoder, numChannels);
        FLAC__stream_encoder_set_bits_per_sample (encoder, jmin ((unsigned int) 24, bitsPerSample));
        FLAC__stream_encoder_set_sample_rate (encoder, (unsigned int) sampleRate);
        FLAC__stream_encoder_set_blocksize (encoder, 0);
        FLAC__stream_encoder_set_do_escape_coding (encoder, true);

        ok = FLAC__stream_encoder_init_stream (encoder,
                                               encodeWriteCallback, encodeSeekCallback,
                                               encodeTellCallback, encodeMetadataCallback,
                                               this) == FlacNamespace::FLAC__STREAM_ENCODER_INIT_STATUS_OK;
    }

    ~FlacWriter() override
    {
        if (ok)
        {
            FlacNamespace::FLAC__stream_encoder_finish (encoder);
            output->flush();
        }
        else
        {
            output = nullptr; // to stop the base class deleting this, as it needs to be returned
                              // to the caller of createWriter()
        }

        FlacNamespace::FLAC__stream_encoder_delete (encoder);
    }

    //==============================================================================
    bool write (const int** samplesToWrite, int numSamples) override
    {
        if (! ok)
            return false;

        HeapBlock<int*> channels;
        HeapBlock<int> temp;
        auto bitsToShift = 32 - (int) bitsPerSample;

        if (bitsToShift > 0)
        {
            temp.malloc (numChannels * (size_t) numSamples);
            channels.calloc (numChannels + 1);

            for (unsigned int i = 0; i < numChannels; ++i)
            {
                if (samplesToWrite[i] == nullptr)
                    break;

                auto* destData = temp.get() + i * (size_t) numSamples;
                channels[i] = destData;

                for (int j = 0; j < numSamples; ++j)
                    destData[j] = (samplesToWrite[i][j] >> bitsToShift);
            }

            samplesToWrite = const_cast<const int**> (channels.get());
        }

        return FLAC__stream_encoder_process (encoder, (const FlacNamespace::FLAC__int32**) samplesToWrite, (unsigned) numSamples) != 0;
    }

    bool writeData (const void* const data, const int size) const
    {
        return output->write (data, (size_t) size);
    }

    static void packUint32 (FlacNamespace::FLAC__uint32 val, FlacNamespace::FLAC__byte* b, const int bytes)
    {
        b += bytes;

        for (int i = 0; i < bytes; ++i)
        {
            *(--b) = (FlacNamespace::FLAC__byte) (val & 0xff);
            val >>= 8;
        }
    }

    void writeMetaData (const FlacNamespace::FLAC__StreamMetadata* metadata)
    {
        using namespace FlacNamespace;
        auto& info = metadata->data.stream_info;

        unsigned char buffer[FLAC__STREAM_METADATA_STREAMINFO_LENGTH];
        const unsigned int channelsMinus1 = info.channels - 1;
        const unsigned int bitsMinus1 = info.bits_per_sample - 1;

        packUint32 (info.min_blocksize, buffer, 2);
        packUint32 (info.max_blocksize, buffer + 2, 2);
        packUint32 (info.min_framesize, buffer + 4, 3);
        packUint32 (info.max_framesize, buffer + 7, 3);
        buffer[10] = (uint8) ((info.sample_rate >> 12) & 0xff);
        buffer[11] = (uint8) ((info.sample_rate >> 4) & 0xff);
        buffer[12] = (uint8) (((info.sample_rate & 0x0f) << 4) | (channelsMinus1 << 1) | (bitsMinus1 >> 4));
        buffer[13] = (FLAC__byte) (((bitsMinus1 & 0x0f) << 4) | (unsigned int) ((info.total_samples >> 32) & 0x0f));
        packUint32 ((FLAC__uint32) info.total_samples, buffer + 14, 4);
        memcpy (buffer + 18, info.md5sum, 16);

        const bool seekOk = output->setPosition (streamStartPos + 4);
        ignoreUnused (seekOk);

        // if this fails, you've given it an output stream that can't seek! It needs
        // to be able to seek back to write the header
        jassert (seekOk);

        output->writeIntBigEndian (FLAC__STREAM_METADATA_STREAMINFO_LENGTH);
        output->write (buffer, FLAC__STREAM_METADATA_STREAMINFO_LENGTH);
    }

    //==============================================================================
    static FlacNamespace::FLAC__StreamEncoderWriteStatus encodeWriteCallback (const FlacNamespace::FLAC__StreamEncoder*,
                                                                              const FlacNamespace::FLAC__byte buffer[],
                                                                              size_t bytes,
                                                                              unsigned int /*samples*/,
                                                                              unsigned int /*current_frame*/,
                                                                              void* client_data)
    {
        return static_cast<FlacWriter*> (client_data)->writeData (buffer, (int) bytes)
                ? FlacNamespace::FLAC__STREAM_ENCODER_WRITE_STATUS_OK
                : FlacNamespace::FLAC__STREAM_ENCODER_WRITE_STATUS_FATAL_ERROR;
    }

    static FlacNamespace::FLAC__StreamEncoderSeekStatus encodeSeekCallback (const FlacNamespace::FLAC__StreamEncoder*, FlacNamespace::FLAC__uint64, void*)
    {
        return FlacNamespace::FLAC__STREAM_ENCODER_SEEK_STATUS_UNSUPPORTED;
    }

    static FlacNamespace::FLAC__StreamEncoderTellStatus encodeTellCallback (const FlacNamespace::FLAC__StreamEncoder*, FlacNamespace::FLAC__uint64* absolute_byte_offset, void* client_data)
    {
        if (client_data == nullptr)
            return FlacNamespace::FLAC__STREAM_ENCODER_TELL_STATUS_UNSUPPORTED;

        *absolute_byte_offset = (FlacNamespace::FLAC__uint64) static_cast<FlacWriter*> (client_data)->output->getPosition();
        return FlacNamespace::FLAC__STREAM_ENCODER_TELL_STATUS_OK;
    }

    static void encodeMetadataCallback (const FlacNamespace::FLAC__StreamEncoder*, const FlacNamespace::FLAC__StreamMetadata* metadata, void* client_data)
    {
        static_cast<FlacWriter*> (client_data)->writeMetaData (metadata);
    }

    bool ok = false;

private:
    FlacNamespace::FLAC__StreamEncoder* encoder;
    int64 streamStartPos;

    JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (FlacWriter)
};


//==============================================================================
FlacAudioFormat::FlacAudioFormat()  : AudioFormat (flacFormatName, ".flac") {}
FlacAudioFormat::~FlacAudioFormat() {}

Array<int> FlacAudioFormat::getPossibleSampleRates()
{
    return { 8000, 11025, 12000, 16000, 22050, 32000, 44100, 48000,
             88200, 96000, 176400, 192000, 352800, 384000 };
}

Array<int> FlacAudioFormat::getPossibleBitDepths()
{
    return { 16, 24 };
}

bool FlacAudioFormat::canDoStereo()     { return true; }
bool FlacAudioFormat::canDoMono()       { return true; }
bool FlacAudioFormat::isCompressed()    { return true; }

AudioFormatReader* FlacAudioFormat::createReaderFor (InputStream* in, const bool deleteStreamIfOpeningFails)
{
    std::unique_ptr<FlacReader> r (new FlacReader (in));

    if (r->sampleRate > 0)
        return r.release();

    if (! deleteStreamIfOpeningFails)
        r->input = nullptr;

    return nullptr;
}

AudioFormatWriter* FlacAudioFormat::createWriterFor (OutputStream* out,
                                                     double sampleRate,
                                                     unsigned int numberOfChannels,
                                                     int bitsPerSample,
                                                     const StringPairArray& /*metadataValues*/,
                                                     int qualityOptionIndex)
{
    if (out != nullptr && getPossibleBitDepths().contains (bitsPerSample))
    {
        std::unique_ptr<FlacWriter> w (new FlacWriter (out, sampleRate, numberOfChannels,
                                                     (uint32) bitsPerSample, qualityOptionIndex));
        if (w->ok)
            return w.release();
    }

    return nullptr;
}

StringArray FlacAudioFormat::getQualityOptions()
{
    return { "0 (Fastest)", "1", "2", "3", "4", "5 (Default)","6", "7", "8 (Highest quality)" };
}

#endif

} // namespace juce