#include "stdafx.h"
#include "mmsystem.h"
#include "math.h"
#include "makewave.h"
#include "realfft.h"

int cbhrecord::isnoise(unsigned char * buf, DWORD size)
{
static double pr[4096];
	int i;
	for(i=0; i<4096; i++)
	{
		pr[i]=(double)(buf[i]-128);
	}
	realfftm(pr,4096);

	double s,smax;
	
	smax=0;
	for(i=15; i<100; i++)
	{
		if(smax<pr[i])
			smax=pr[i];
	}
	s=0;
	for(i=2000;i<2048;i++)
		s+=pr[i];
	s/=48;
	if(s<=0.00000001)
		noiselevel = 0;
	else
	noiselevel = smax/s;
	if(noiselevel<150)
		return 1;
	return 0;
}

int cbhrecord::start(HWND hWnd)
{
//	if(state)
//		return 0;
	if(!hWnd)
		return 0;
	DWORD i;
	rsize = 0;
	i=waveInOpen(&hwavein,WAVE_MAPPER,&waveformat,(WORD)hWnd,0,CALLBACK_WINDOW);
	i=waveInPrepareHeader(hwavein,&pwh1,sizeof(pwh1));
	i=waveInAddBuffer(hwavein,&pwh1, sizeof(pwh1));
	i=waveInPrepareHeader(hwavein,&pwh2,sizeof(pwh2));
	i=waveInAddBuffer(hwavein,&pwh2, sizeof(pwh2));
	i=waveInStart(hwavein);
	state = 1;
	rsize = 0;
	return 1;
}

int cbhrecord::stop()
{
	if(!state) return 1;
	DWORD i;
	i=waveInStop(hwavein);
	i=waveInReset(hwavein);
	i=waveInUnprepareHeader(hwavein, &pwh1, sizeof(pwh1));
	i=waveInUnprepareHeader(hwavein, &pwh2, sizeof(pwh2));
	i=waveInClose(hwavein);
	state = 0;
	return 1;
}

int cbhrecord::resycle(DWORD p)
{
	if(!p) return 1;
	if(rsize == tbsize) return 1;
	LPWAVEHDR pwh = (LPWAVEHDR)p;
	DWORD i;
	i=waveInUnprepareHeader(hwavein, pwh, sizeof(WAVEHDR));
	if(rsize+(pwh->dwBytesRecorded)>tbsize)
	{
		stop();
		return 1;
	}
	int j;
	j = isnoise((unsigned char*)pwh->lpData,pwh->dwBytesRecorded);
	if(j && (state==1)) {
		i=waveInPrepareHeader(hwavein,pwh,sizeof(WAVEHDR));
		i=waveInAddBuffer(hwavein,pwh, sizeof(WAVEHDR));
		return 0;
	}
	if(state==1)state=2;
	memcpy(tbuffer+rsize,pwh->lpData,pwh->dwBytesRecorded);
	rsize += pwh->dwBytesRecorded;
	if(j)
		state++;
	else
		state=2;
	i=waveInPrepareHeader(hwavein,pwh,sizeof(WAVEHDR));
	i=waveInAddBuffer(hwavein,pwh, sizeof(WAVEHDR));
	if((rsize >= tbsize) || (state>7)){
		if(state>7) {
			state -=4;
			if((double)rsize-state*bsize>0)
				rsize-=state*bsize;
		}
		stop();
		return 1;
	}
	return 0;
}