#include <windows.h>
#include "Peaks_R.h"


void __cdecl cPeaksMZ(long double* data, int* startMZ, int* endMZ, int* firstMZ, int* lastMZ, int* length, long double* span, int* ret)
{

	long double MZStep = (*lastMZ - *firstMZ) / ((long double)(*length) - 1);
	int leftEdge, rightEdge, curSpan;
	long double curValue;

	for (int curPos = (int)( (long double)(*startMZ - *firstMZ) / MZStep ); curPos < (int)( (long double)(*endMZ - *firstMZ) / MZStep ); curPos++)
	{
		curValue = data[curPos];
		curSpan  = (int)( ( (long double)curPos + ((long double)*firstMZ /  MZStep) ) * *span );

		// Calculate the edges
		leftEdge = curPos - curSpan;
		if (leftEdge < 0) { leftEdge = 0; }

		rightEdge = curPos + curSpan;
		if (rightEdge >= *length) { rightEdge = *length - 1; }

		// Check if this position has a higher value than anything within the span
		ret[curPos] = 1;
		for (int compPos = leftEdge; compPos <= rightEdge; compPos++)
		{
			if (data[compPos] >= curValue) { if (compPos != curPos) {ret[curPos] = 0; compPos = *length;} }
		}
	}

}


void __cdecl cPeakAreaMZ(long double* data, int* startMZ, int* endMZ, int* firstMZ, int* lastMZ, int* length, long double* span, long double* ret)
{

	long double MZStep = (*lastMZ - *firstMZ) / ((long double)(*length) - 1);
	
	long double negFactor, posFactor, sum, localSum;
	int left, right, sumPos;
	int curSpan, negSpan;


	for (int curPos = (int)( (long double)(*startMZ - *firstMZ) / MZStep ); curPos < (int)( (long double)(*endMZ - *firstMZ) / MZStep ); curPos++)
	{
		curSpan = (int)( ( (long double)curPos + ((long double)*firstMZ /  MZStep) ) * *span );

		negSpan = (int)((long double)curSpan * (long double)0.2);
		if (negSpan < 1) { negSpan = 1; }

		negFactor = -(long double)0.5 / (long double)negSpan;
		posFactor = 1 / (long double)(2 * curSpan + 1 - 2 * negSpan);

		left  = curPos - curSpan;
		right = curPos + curSpan;

		sum = 0;

		// Only continue if the span does not fall of an edge
		if ( (left >= 0) && (right < *length) ) {
			// Sum the left negative lobe
			localSum = 0;
			for (sumPos = left; sumPos < left + negSpan; sumPos++) {
				localSum += data[sumPos];
			}
			sum += (localSum * negFactor);

			// Sum the positive region
			localSum = 0;
			for (sumPos = left + negSpan; sumPos <= right - negSpan; sumPos++) {
				localSum += data[sumPos];
			}
			sum += (localSum * posFactor);

			// Sum the right negative lobe
			localSum = 0;
			for (sumPos = right - negSpan + 1; sumPos <= right; sumPos++) {
				localSum += data[sumPos];
			}
			sum += (localSum * negFactor);
		}

		ret[curPos] = sum;
	}
}