#include <ap_int.h>
#include <ap_axi_sdata.h>
#include <hls_stream.h>
#include <ap_axi_sdata.h>
#include "hls_math.h"
#define consta 16807

struct data_type{
	float data;
	bool last;
};

static float hist[5] = { 1, 2, 3, 4, 5 };
static float p[5] = { 0.2, 0.2, 0.2, 0.2, 0.2 };
typedef unsigned long long int llint;
typedef unsigned long lint;
static llint seed31 = 10;


void randn(float* randno){
#pragma HLS INLINE off
	lint hi, lo;
	lo = consta * (seed31 & 0xFFFF);
	hi = consta * (seed31 >> 16);
	lo += (hi & 0x7FFF) << 16;
	lo += hi >> 15;
	if (lo > 0x7FFFFFFF) lo -= 0x7FFFFFFF;
	seed31 = (long)lo;
	*randno = seed31 / 2147483647.0f;

}

void las(data_type A[5], data_type B[5], int s, int* index, float* randno)
{
	float minm, maxm, sum;
	float beata, rate, rno;
#pragma HLS INTERFACE axis port=A
#pragma HLS INTERFACE axis port=B
#pragma HLS INTERFACE ap_ctrl_none port=return
#pragma HLS INTERFACE s_axilite port=index
#pragma HLS INTERFACE s_axilite port=s
#pragma HLS INTERFACE s_axilite port=randno

	int i;
	float alpha = 0.9;


	const float a = 0.078;
	const float b = 0.006;
	float cum_p[5] = { 0.2, 0.4, 0.6, 0.8, 1.0 };


	minm = hist[0];
	maxm = hist[4];
	for (i = 0; i<5; i++){
		hist[i] = A[i].data*alpha + hist[i] * (1 - alpha);
		B[i].data = hist[i];
		B[i].last = A[i].last;

		if (hist[i]<minm){
			minm = hist[i];

		}
		if (hist[i]>maxm){
			maxm = hist[i];

		}


	}

	{
		beata = (hist[s] - minm) / (maxm - minm);
		rate = 1.0f - beata;


		for (i = 0; i<5; i++)
		{
			if (i == s)
				p[i] = p[i] + rate*a*(1 - p[i]) - b*beata*p[i];
			else
				p[i] = p[i] - rate*a*p[i] + b*beata*((1.0 / 4.0f) - p[i]);
		}
		sum = 0.0;
		for (i = 0; i<5; i++)
		{
			sum = sum + p[i];
			cum_p[i] = sum;

		}

	}

	randn(randno);

	for (i = 0; i<5; i++)
	{
		if (*(randno)<cum_p[i]){
			*index = i;
			break;
		}
	}

}