#include "RtAudio.h"
#include <math.h>
#include <stdio.h>
#include <iostream>
using namespace std;

#define SAMPLE double
#define MY_PIE 3.14159265358979
#define MY_SRATE 44100

// delay buffer
SAMPLE * g_delay = NULL;
// max delay length
long g_delayMax = 200000;
// delay length
long g_delayLen = MY_SRATE;
// read and write indices
long g_reader = 0;
long g_writer = 0;

// callback
int callme( char * buffer, int buffer_size, void * user_data )
{
    fprintf( stderr, "THOR" );
    SAMPLE * buffy = (SAMPLE *)buffer;

    for( int i = 0; i < buffer_size; i++ )
    {
        // write into the delay
        g_delay[g_writer] = buffy[i];
        
        // read out of the buffer
        buffy[i] = g_delay[g_reader];
        
        // increment
        g_writer++;
        g_reader++;
        // warp
        g_writer %= g_delayMax;
        g_reader %= g_delayMax;
    }
    
    return 0;
}

// entry point
int main( int argc, char ** argv )
{
    // RtAudio pointer
    RtAudio * audio = NULL;
    // buffer size
    int buffer_size = 512;
    
    // create the RtAudio
    try {
        audio = new RtAudio(
            0, // device number of output
            1, // number of output channels
            0, // device number for input
            1, // number of input channels
            RTAUDIO_FLOAT64, // format
            MY_SRATE, // sample rate
            &buffer_size, // buffer size
            8 // number of buffers
        );
    } catch( RtError & err ) {
        err.printMessage();
        exit(1);
    }

    // allocate delay
    g_delay = new SAMPLE[g_delayMax];
    // zero out
    memset( g_delay, 0, sizeof(SAMPLE)*g_delayMax );
    // sanity check
    assert( g_delayLen <= g_delayMax );
    // set indices
    g_reader = g_writer - g_delayLen;
    // wrap
    if( g_reader < 0 ) g_reader += g_delayMax;
    
    
    // set the callback
    try {
        audio->setStreamCallback( &callme, NULL );
        audio->startStream();
    } catch( RtError & err ) {
        // do stuff
        err.printMessage();
        goto cleanup;
    }
    
    // something needs to happen here
    while( true )
    {
        usleep( 10000 );
    }
    
    // if we get here, then stop!
    try {
        audio->stopStream();
    } catch( RtError & err ) {
        // do stuff
        err.printMessage();
    }

cleanup:
    audio->closeStream();
    delete audio;
    
    return 0;
}