/******************************************/
/*
  playsaw.cpp
  by Gary P. Scavone, 2006

  This program will output sawtooth waveforms
  of different frequencies on each channel.
*/
/******************************************/

#include "RtAudio.h"
#include <iostream>
#include <fstream>
#include <cstdlib>
#include <cstdio>
#include <ctime>
#include <cmath>
#include <string>
using namespace std;

typedef double SAMPLE;
#define FORMAT RTAUDIO_FLOAT64
#define SCALE  1.0

#define BASE_RATE 0.005
#define TIME   1.0

#define CHANNELS 1

#define PI 3.14159265358979
#define SAMPLE_RATE 44100


#define NOT_IMPLEMENTED cout << "Not implemented!\n"; exit(-1)

RtAudio::StreamOptions g_options;
SAMPLE g_freq = 440;
SAMPLE g_t = 0;
double g_pulse_width = .5;
bool g_use_input = false;

ofstream myfile;

void usage_and_exit() {
    cout << "usage:\n\n";
    cout << "sig-gen [type] [input] [frequency] [width]\n";
    cout << "   [type]: --sine | --saw | --pulse | --noise | --impulse\n";
    cout << "   [input]: --input (optional flag to multiply the signal times standard input)\n";
    cout << "   [frequency]: (a number > 0, only applicable to some signal types)\n";
    cout << "   [width]: pulse width (only applicable to some signal types)\n";

    exit(0);
}

int sine_callback(void *outputBuffer, void *inputBuffer, unsigned int nBufferFrames,
         double streamTime, RtAudioStreamStatus status, void* user_data) {

    SAMPLE * obuffy = (SAMPLE *)outputBuffer;
    SAMPLE * ibuffy = (SAMPLE *)inputBuffer;
    
    for( unsigned i = 0; i < nBufferFrames; i++ )
    {
        obuffy[i] = sin( 2 * PI * g_freq * g_t / SAMPLE_RATE );
        g_t += 1.0;

        //if (g_use_input) obuffy[i] *= ibuffy[i];
    }
    
    return 0;
}

int saw_callback(void *outputBuffer, void *inputBuffer, unsigned int nBufferFrames,
         double streamTime, RtAudioStreamStatus status, void* user_data) {

    SAMPLE * obuffy = (SAMPLE *)outputBuffer;
    SAMPLE * ibuffy = (SAMPLE *)inputBuffer;
    
    for( unsigned i = 0; i < nBufferFrames; i++ )
    {
        if (g_t <= SAMPLE_RATE / g_freq * g_pulse_width) {
            SAMPLE interp = g_t / (SAMPLE_RATE / g_freq * g_pulse_width) * 2 - 1;
            obuffy[i] = interp;
        } else {
            SAMPLE interp = - ( g_t - (SAMPLE_RATE / g_freq * g_pulse_width) ) / (SAMPLE_RATE / g_freq * (1 - g_pulse_width)) * 2 + 1;
            obuffy[i] = interp;
        }
        

        if (g_t > SAMPLE_RATE / g_freq) {
            g_t -= SAMPLE_RATE / g_freq;
        }
        g_t += 1.0;

        if (g_use_input) obuffy[i] *= ibuffy[i];
    }
    
    myfile.write ( (char*)outputBuffer, nBufferFrames * sizeof(SAMPLE) );
    return 0;
}

int pulse_callback(void *outputBuffer, void *inputBuffer, unsigned int nBufferFrames,
         double streamTime, RtAudioStreamStatus status, void* user_data) {

    SAMPLE * obuffy = (SAMPLE *)outputBuffer;
    SAMPLE * ibuffy = (SAMPLE *)inputBuffer;
    
    for( unsigned i = 0; i < nBufferFrames; i++ )
    {
        obuffy[i] = -1.0;
        if (g_t > SAMPLE_RATE / g_freq * g_pulse_width) {
            obuffy[i] = 1.0;
        }

        if (g_t > SAMPLE_RATE / g_freq) {
            g_t -= SAMPLE_RATE / g_freq;
        }
        g_t += 1.0;

        if (g_use_input) obuffy[i] *= ibuffy[i];
    }
    
    return 0;
}

int impulse_callback(void *outputBuffer, void *inputBuffer, unsigned int nBufferFrames,
         double streamTime, RtAudioStreamStatus status, void* user_data) {

    SAMPLE * obuffy = (SAMPLE *)outputBuffer;
    SAMPLE * ibuffy = (SAMPLE *)inputBuffer;
    
    for( unsigned i = 0; i < nBufferFrames; i++ )
    {
        obuffy[i] = 0;
        if (g_t > SAMPLE_RATE / g_freq) {
            obuffy[i] = 1.0;
            g_t -= SAMPLE_RATE / g_freq;
        }
        g_t += 1.0;

        if (g_use_input) obuffy[i] *= ibuffy[i];
    }
    
    return 0;
}

int noise_callback(void *outputBuffer, void *inputBuffer, unsigned int nBufferFrames,
         double streamTime, RtAudioStreamStatus status, void* user_data) {

    SAMPLE * obuffy = (SAMPLE *)outputBuffer;
    SAMPLE * ibuffy = (SAMPLE *)inputBuffer;
    
    for( unsigned i = 0; i < nBufferFrames; i++ )
    {
        obuffy[i] = (double)rand() / RAND_MAX * 2 - 1;

        if (g_use_input) obuffy[i] *= ibuffy[i];
    }
    
    return 0;
}

int main( int argc, char* argv[] )
{
    unsigned int buffer_frames, device = 0, offset = 0;
    RtAudio dac;

    int (*audio_callback)(void*, void*, unsigned int, double, RtAudioStreamStatus, void*);
    audio_callback = &sine_callback;

    myfile.open ("rawout", ios::binary);


    cout << "\n=== REALTIME SIGNAL GENERATOR ===\n\n";

    if ( dac.getDeviceCount() < 1 ) {
        std::cout << "No audio devices found!\n";
        exit( 1 );
    }

    // get arguments
    if (argc < 2 || argc > 5) usage_and_exit();

    int param_num = 0;
    for (int i = 1; i < argc; i++) {
        string arg = argv[i];
        if (arg[0] == '-' && arg[1] == '-') {
            if (arg == "--sine") {
                audio_callback = &sine_callback;
                cout << "sine (freq = " << g_freq << ")\n";
            } else if (arg == "--saw") {
                audio_callback = &saw_callback;
                cout << "saw (freq = " << g_freq << ", pulse width = " << g_pulse_width << ")\n";
            } else if (arg == "--pulse") {
                audio_callback = &pulse_callback;
                cout << "pulse (freq = " << g_freq << ", pulse width = " << g_pulse_width << ")\n";
            } else if (arg == "--noise") {
                srand (time(NULL));
                audio_callback = &noise_callback;
                cout << "noise (uniform distribution)\n";
            } else if (arg == "--impulse") {
                audio_callback = &impulse_callback;
                cout << "impulse (freq = " << g_freq << ")\n";
            } else if (arg == "--input") {
                g_use_input = true;
            } else {
                cout << "unrecognized option \"" << arg << "\"\n";
                usage_and_exit();
            }
        } else {

            switch (param_num) {
            case 0:
                g_freq = atof( arg.c_str() );
                if (g_freq <= 0) {
                    cout << "bad frequency \"" << arg << "\"\n";
                    usage_and_exit();
                }
                break;
            case 1:
                g_pulse_width = atof( arg.c_str() );
                if (g_pulse_width < 0 || g_pulse_width > 1) {
                    cout << "bad pulse width \"" << arg << "\"\n";
                    usage_and_exit();
                }
                break;
            }
            param_num++;

        }
    }

    double *data = (double *) calloc( CHANNELS, sizeof( double ) );

    // Let RtAudio print messages to stderr.
    dac.showWarnings( true );

    buffer_frames = 512;
    RtAudio::StreamParameters iParams;
    iParams.deviceId = 0;//dac.getDefaultInputDevice();
    iParams.nChannels = CHANNELS;
    iParams.firstChannel = offset;
    RtAudio::StreamParameters oParams;
    oParams.deviceId = 0;//dac.getDefaultOutputDevice();
    oParams.nChannels = CHANNELS;
    oParams.firstChannel = offset;

    cout << "iparam channels: " << iParams.nChannels << endl;
    cout << "oparam channels: " << oParams.nChannels << endl;

    //g_options.flags |= RTAUDIO_HOG_DEVICE;
    //g_options.flags |= RTAUDIO_SCHEDULE_REALTIME;
    
    

    try {
        //if (g_use_input)
            dac.openStream( &oParams, &iParams, FORMAT, SAMPLE_RATE, &buffer_frames, audio_callback, NULL, &g_options );
        //else
        //  dac.openStream( &oParams, NULL, FORMAT, SAMPLE_RATE, &buffer_frames, audio_callback, NULL, &g_options );

        dac.startStream();
    }
        catch ( RtError& e ) {
        e.printMessage();
        goto cleanup;
    }

    char input;
    //std::cout << "Stream latency = " << dac.getStreamLatency() << "\n" << std::endl;
    cout << "Playing ... press <enter> to quit. (buffer size = " << buffer_frames << ")\n";
    std::cin.get( input );
    myfile.close();

    try {
        // Stop the stream
        dac.stopStream();
    }
    catch ( RtError& e ) {
        e.printMessage();
    }

    cleanup:
    if ( dac.isStreamOpen() ) dac.closeStream();
    free( data );

    return 0;
}