#if defined (__USE_LPCOPEN)
#if defined(NO_BOARD_LIB)
#include "chip.h"
#else
#include "board.h"
#endif
#endif
#include <cr_section_macros.h>
#include <math.h>
#include "arm_math.h"
#include "oled.h"
#define _LPC_ADC_ID LPC_ADC
#define FS 32000
#define FFT_N 256
#define FFT_2N (FFT_N*2)
#define FFT_N2 (FFT_N/2)
arm_cfft_radix4_instance_f32 fftInstance;
float32_t x_buff[FFT_2N]={0};
float32_t x_buff_point[FFT_2N]={0};
float32_t win[FFT_N];
float32_t in_buff[FFT_N];
uint32_t wr=0;
uint16_t dataADC;
volatile bool f1=false;

void SysTick_Handler(void)
{
	for(int i=0; i<FFT_2N; i++){
		if(x_buff_point[i]>0){
			x_buff_point[i]--;
		}
	}
}

/*--------------------------------------------------------------------------------*/
void Spectrum_Line_f32(float32_t *pSrc, uint32_t numSamples)
{
	uint16_t y=0, y1=63;
	for(int i=1; i<numSamples; i++){
		y=63-pSrc[i];
		OLED_Draw_Line(i-1, y1,i, y);
		y1=y;
	}
}
/*--------------------------------------------------------------------------------*/
void Spectrum_Log_Line_f32(float32_t *pSrc, uint32_t numSamples)
{
	uint16_t y=0, y1=63;
	for(int i=1; i<numSamples; i++){
		y=40*log10(1/((pSrc[i]/(float32_t)FFT_N2)+0.026)); // -32 dB
		OLED_Draw_Line(i-1, y1,i, y);
		y1=y;
	}
}
/*--------------------------------------------------------------------------------*/

void Spectrum_Bar_f32(float32_t *pSrc, uint32_t numSamples, bool peak)
{
	for(int i=1; i<numSamples; i=i+4){
		uint16_t y=pSrc[i]; // -32 dB
		OLED_Draw_Line(i, 0,i, y);
		if(pSrc[i]>x_buff_point[i]){
			x_buff_point[i]=pSrc[i];
		}

		OLED_Draw_Point(i,1+x_buff_point[i],1);

	}

}
/*--------------------------------------------------------------------------------*/
void ADC_IRQHandler(void){
	Chip_ADC_ReadValue(_LPC_ADC_ID, ADC_CH0, &dataADC);
	if(f1==false){
		in_buff[wr++]=(dataADC-2048)/2048.0;
		if(wr==FFT_N){
			f1=true;
			wr=0;
		}
	}
}


/*--------------------------------------------------------------------------------*/
int main(void) {
	arm_cfft_radix4_init_f32(&fftInstance, FFT_N, 0, 1);
	static ADC_CLOCK_SETUP_T ADCSetup;
	uint32_t timerFreq;
#if defined (__USE_LPCOPEN)
	// Read clock settings and update SystemCoreClock variable
	SystemCoreClockUpdate();
#if !defined(NO_BOARD_LIB)
	// Set up and initialize all required blocks and
	// functions related to the board hardware
	Board_Init();
	// Set the LED to the state of "On"
	Board_LED_Set(0, true);
#endif
#endif
	// TODO: insert code here
	/*--------------------- OLED Init -----------------------*/
	OLED_Init();
	SysTick_Config(SystemCoreClock / 64);
	/*--------------------- ADC Init ------------------------*/
	Chip_ADC_Init(_LPC_ADC_ID, &ADCSetup);
	Chip_ADC_Int_SetChannelCmd(_LPC_ADC_ID, ADC_CH0, ENABLE);
	Chip_ADC_EnableChannel(_LPC_ADC_ID, ADC_CH0, ENABLE);
	NVIC_ClearPendingIRQ(ADC_IRQn);
	NVIC_EnableIRQ(ADC_IRQn);
	Chip_ADC_SetStartMode(_LPC_ADC_ID, ADC_START_ON_ADCTRIG0, ADC_TRIGGERMODE_RISING);
	/*-------------------- Timer32_0 Init --------------------*/
	Chip_TIMER_Init(LPC_TIMER32_0);
	timerFreq = Chip_Clock_GetSystemClockRate();
	Chip_TIMER_Reset(LPC_TIMER32_0);
	Chip_TIMER_MatchEnableInt(LPC_TIMER32_0, 0);
	Chip_TIMER_SetMatch(LPC_TIMER32_0, 0, (timerFreq / (2*FS)));
	Chip_TIMER_ResetOnMatchEnable(LPC_TIMER32_0, 0);
	Chip_TIMER_ExtMatchControlSet(LPC_TIMER32_0, 0, TIMER_EXTMATCH_TOGGLE, 0);
	Chip_TIMER_Enable(LPC_TIMER32_0);
	/*-------------------- End of Init ----------------------*/
	// Time Window
	for(int n=0; n<FFT_N;n++){
		//win[n]=1; // Rect
		win[n]=(0.5*(1-arm_cos_f32(2*PI*n/(FFT_N-1)))); // Hann
	}
	while(1) {
		if(f1){
			for(int i=0; i<FFT_N;i++){
				x_buff[i*2]=win[i]*in_buff[i];
				x_buff[i*2+1]=0;
			}
			arm_cfft_radix4_f32(&fftInstance, x_buff);
			arm_cmplx_mag_f32(x_buff, x_buff, FFT_N);
			OLED_Clear_Screen(0);
			OLED_Puts(0, 0 ,"Real-Time FFT Radix-4");
			for(int i=0; i<FFT_N;i++)
				x_buff[i]*=(0.25*i);// emphase
			//Spectrum_Log_Line_f32(x_buff, FFT_N2);
			Spectrum_Bar_f32(x_buff, FFT_N2, 1);
			OLED_Refresh_Gram();
			f1=false;
		}
	}
	return 0 ;
}