/************************** BEGIN Soundfile.h **************************
 FAUST Architecture File
 Copyright (C) 2003-2022 GRAME, Centre National de Creation Musicale
 ---------------------------------------------------------------------
 This program is free software; you can redistribute it and/or modify
 it under the terms of the GNU Lesser General Public License as published by
 the Free Software Foundation; either version 2.1 of the License, or
 (at your option) any later version.
 
 This program is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 GNU Lesser General Public License for more details.
 
 You should have received a copy of the GNU Lesser General Public License
 along with this program; if not, write to the Free Software
 Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 
 EXCEPTION : As a special exception, you may create a larger work
 that contains this FAUST architecture section and distribute
 that work under terms of your choice, so long as this FAUST
 architecture section is not modified.
 ********************************************************************/

#ifndef __Soundfile__
#define __Soundfile__

#include <string.h>
#include <string>
#include <vector>

#ifndef FAUSTFLOAT
#define FAUSTFLOAT float
#endif

#define BUFFER_SIZE 1024
#define SAMPLE_RATE 44100
#define MAX_CHAN 64
#define MAX_SOUNDFILE_PARTS 256

#ifdef _MSC_VER
#define PRE_PACKED_STRUCTURE __pragma(pack(push, 1))
#define POST_PACKED_STRUCTURE \
    ;                         \
    __pragma(pack(pop))
#else
#define PRE_PACKED_STRUCTURE
#define POST_PACKED_STRUCTURE __attribute__((__packed__))
#endif

/*
 The soundfile structure to be used by the DSP code. Soundfile has a MAX_SOUNDFILE_PARTS parts 
 (even a single soundfile or an empty soundfile). 
 The fLength, fOffset and fSR fields are filled accordingly by repeating the actual parts if needed.
 The fBuffers contains MAX_CHAN non-interleaved arrays of samples.
 
 It has to be 'packed' to that the LLVM backend can correctly access it.

 Index computation:
    - p is the current part number [0..MAX_SOUNDFILE_PARTS-1] (must be proved by the type system)
    - i is the current position in the part. It will be constrained between [0..length]
    - idx(p,i) = fOffset[p] + max(0, min(i, fLength[p]));
*/

PRE_PACKED_STRUCTURE
struct Soundfile {
    void* fBuffers; // will correspond to a double** or float** pointer chosen at runtime
    int* fLength;   // length of each part (so fLength[P] contains the length in frames of part P)
    int* fSR;       // sample rate of each part (so fSR[P] contains the SR of part P)
    int* fOffset;   // offset of each part in the global buffer (so fOffset[P] contains the offset in frames of part P)
    int fChannels;  // max number of channels of all concatenated files
    int fParts;     // the total number of loaded parts
    bool fIsDouble; // keep the sample format (float or double)

    Soundfile(int cur_chan, int length, int max_chan, int total_parts, bool is_double)
    {
        fLength   = new int[MAX_SOUNDFILE_PARTS];
        fSR       = new int[MAX_SOUNDFILE_PARTS];
        fOffset   = new int[MAX_SOUNDFILE_PARTS];
        fIsDouble = is_double;
        fChannels = cur_chan;
        fParts    = total_parts;
        if (fIsDouble) {
            fBuffers = allocBufferReal<double>(cur_chan, length, max_chan);
        } else {
            fBuffers = allocBufferReal<float>(cur_chan, length, max_chan);
        }
    }
    
    template <typename REAL>
    void* allocBufferReal(int cur_chan, int length, int max_chan)
    {
        REAL** buffers = new REAL*[max_chan];
        for (int chan = 0; chan < cur_chan; chan++) {
            buffers[chan] = new REAL[length];
            memset(buffers[chan], 0, sizeof(REAL) * length);
        }
        return buffers;
    }
    
    void copyToOut(int size, int channels, int max_channels, int offset, void* buffer)
    {
        if (fIsDouble) {
            copyToOutReal<double>(size, channels, max_channels, offset, buffer);
       } else {
            copyToOutReal<float>(size, channels, max_channels, offset, buffer);
        }
    }
    
    void shareBuffers(int cur_chan, int max_chan)
    {
        // Share the same buffers for all other channels so that we have max_chan channels available
        if (fIsDouble) {
            for (int chan = cur_chan; chan < max_chan; chan++) {
                static_cast<double**>(fBuffers)[chan] = static_cast<double**>(fBuffers)[chan % cur_chan];
            }
        } else {
            for (int chan = cur_chan; chan < max_chan; chan++) {
                static_cast<float**>(fBuffers)[chan] = static_cast<float**>(fBuffers)[chan % cur_chan];
            }
        }
    }
    
    template <typename REAL>
    void copyToOutReal(int size, int channels, int max_channels, int offset, void* buffer)
    {
        for (int sample = 0; sample < size; sample++) {
            for (int chan = 0; chan < channels; chan++) {
                static_cast<REAL**>(fBuffers)[chan][offset + sample] = static_cast<REAL*>(buffer)[sample * max_channels + chan];
            }
        }
    }
    
    template <typename REAL>
    void getBuffersOffsetReal(void* buffers, int offset)
    {
        for (int chan = 0; chan < fChannels; chan++) {
            static_cast<REAL**>(buffers)[chan] = &(static_cast<REAL**>(fBuffers))[chan][offset];
        }
    }
    
    void emptyFile(int part, int& offset)
    {
        fLength[part] = BUFFER_SIZE;
        fSR[part] = SAMPLE_RATE;
        fOffset[part] = offset;
        // Update offset
        offset += fLength[part];
    }
 
    ~Soundfile()
    {
        // Free the real channels only
        if (fIsDouble) {
            for (int chan = 0; chan < fChannels; chan++) {
                delete[] static_cast<double**>(fBuffers)[chan];
            }
            delete[] static_cast<double**>(fBuffers);
        } else {
            for (int chan = 0; chan < fChannels; chan++) {
                delete[] static_cast<float**>(fBuffers)[chan];
            }
            delete[] static_cast<float**>(fBuffers);
        }
        delete[] fLength;
        delete[] fSR;
        delete[] fOffset;
    }

    typedef std::vector<std::string> Directories;
    
} POST_PACKED_STRUCTURE;

/*
 The generic soundfile reader.
 */

class SoundfileReader {
    
   protected:
    
    int fDriverSR;
   
    // Check if a soundfile exists and return its real path_name
    std::string checkFile(const Soundfile::Directories& sound_directories, const std::string& file_name)
    {
        if (checkFile(file_name)) {
            return file_name;
        } else {
            for (size_t i = 0; i < sound_directories.size(); i++) {
                std::string path_name = sound_directories[i] + "/" + file_name;
                if (checkFile(path_name)) { return path_name; }
            }
            return "";
        }
    }
    
    bool isResampling(int sample_rate) { return (fDriverSR > 0 && fDriverSR != sample_rate); }
 
    // To be implemented by subclasses

    /**
     * Check the availability of a sound resource.
     *
     * @param path_name - the name of the file, or sound resource identified this way
     *
     * @return true if the sound resource is available, false otherwise.
     */
    virtual bool checkFile(const std::string& path_name) = 0;
    
    /**
     * Check the availability of a sound resource.
     *
     * @param buffer - the sound buffer
     * @param size - the sound buffer length
     *
     * @return true if the sound resource is available, false otherwise.
     */

    virtual bool checkFile(unsigned char* buffer, size_t size) { return true; }

    /**
     * Get the channels and length values of the given sound resource.
     *
     * @param path_name - the name of the file, or sound resource identified this way
     * @param channels - the channels value to be filled with the sound resource number of channels
     * @param length - the length value to be filled with the sound resource length in frames
     *
     */
    virtual void getParamsFile(const std::string& path_name, int& channels, int& length) = 0;
    
    /**
     * Get the channels and length values of the given sound resource.
     *
     * @param buffer - the sound buffer
     * @param size - the sound buffer length
     * @param channels - the channels value to be filled with the sound resource number of channels
     * @param length - the length value to be filled with the sound resource length in frames
     *
     */
    virtual void getParamsFile(unsigned char* buffer, size_t size, int& channels, int& length) {}

    /**
     * Read one sound resource and fill the 'soundfile' structure accordingly
     *
     * @param soundfile - the soundfile to be filled
     * @param path_name - the name of the file, or sound resource identified this way
     * @param part - the part number to be filled in the soundfile
     * @param offset - the offset value to be incremented with the actual sound resource length in frames
     * @param max_chan - the maximum number of mono channels to fill
     *
     */
    virtual void readFile(Soundfile* soundfile, const std::string& path_name, int part, int& offset, int max_chan) = 0;
    
    /**
     * Read one sound resource and fill the 'soundfile' structure accordingly
     *
     * @param soundfile - the soundfile to be filled
     * @param buffer - the sound buffer
     * @param size - the sound buffer length
     * @param part - the part number to be filled in the soundfile
     * @param offset - the offset value to be incremented with the actual sound resource length in frames
     * @param max_chan - the maximum number of mono channels to fill
     *
     */
    virtual void readFile(Soundfile* soundfile, unsigned char* buffer, size_t size, int part, int& offset, int max_chan) {}

  public:
    
    SoundfileReader() {}
    virtual ~SoundfileReader() {}
    
    void setSampleRate(int sample_rate) { fDriverSR = sample_rate; }
   
    Soundfile* createSoundfile(const std::vector<std::string>& path_name_list, int max_chan, bool is_double)
    {
        try {
            int cur_chan = 1; // At least one channel
            int total_length = 0;
            
            // Compute total length and channels max of all files
            for (size_t i = 0; i < path_name_list.size(); i++) {
                int chan, length;
                if (path_name_list[i] == "__empty_sound__") {
                    length = BUFFER_SIZE;
                    chan = 1;
                } else {
                    getParamsFile(path_name_list[i], chan, length);
                }
                cur_chan = std::max<int>(cur_chan, chan);
                total_length += length;
            }
           
            // Complete with empty parts
            total_length += (MAX_SOUNDFILE_PARTS - path_name_list.size()) * BUFFER_SIZE;
            
            // Create the soundfile
            Soundfile* soundfile = new Soundfile(cur_chan, total_length, max_chan, path_name_list.size(), is_double);
            
            // Init offset
            int offset = 0;
            
            // Read all files
            for (size_t i = 0; i < path_name_list.size(); i++) {
                if (path_name_list[i] == "__empty_sound__") {
                    soundfile->emptyFile(i, offset);
                } else {
                    readFile(soundfile, path_name_list[i], i, offset, max_chan);
                }
            }
            
            // Complete with empty parts
            for (size_t i = path_name_list.size(); i < MAX_SOUNDFILE_PARTS; i++) {
                soundfile->emptyFile(i, offset);
            }
            
            // Share the same buffers for all other channels so that we have max_chan channels available
            soundfile->shareBuffers(cur_chan, max_chan);
            return soundfile;
            
        } catch (...) {
            return nullptr;
        }
    }

    // Check if all soundfiles exist and return their real path_name
    std::vector<std::string> checkFiles(const Soundfile::Directories& sound_directories,
                                        const std::vector<std::string>& file_name_list)
    {
        std::vector<std::string> path_name_list;
        for (size_t i = 0; i < file_name_list.size(); i++) {
            std::string path_name = checkFile(sound_directories, file_name_list[i]);
            // If 'path_name' is not found, it is replaced by an empty sound (= silence)
            path_name_list.push_back((path_name == "") ? "__empty_sound__" : path_name);
        }
        return path_name_list;
    }

};

#endif
/**************************  END  Soundfile.h **************************/
