l6 dsp

function [V] = flanger(inputPath, outputPath, maxSize, minSize, val, step)

if(val > maxSize || val < minSize)
    disp('val has to be between minSize and maxSize!');
    val = randi(minSize, maxSize, 1);
end


[Y, FS] = audioread(inputPath);

%rd = uint32(1);
%wr = uint32(1);

rd = 1;
wr = val - 1;

Z = Y;

buf = Y(1:val) / 2;

for i = 1:length(Y)
    if((mod(i, val) == 0 )|| (mod(i, val) > val))
        val = val + step;

        if (val < minSize)
            val = maxSize;
        end
        if (val > maxSize)
            val = minSize;
        end

        rd = 1;
        wr = val - 1;

        if ((i + val) < length(Y))
            buf = Y(i : i + val) / 2;
        end
    end

    Z(i) = Y(i) / 2;

    %disp('i == ');
    %disp(i);

    buf(wr) = Z(i);
    wr = mod((wr + 1), (val)) + 1;

    %disp('rd == ');
    %disp(rd);
    %disp('val == ');
    %disp(val);

    Z(i) = Z(i) + buf(rd);
    rd = mod((rd + 1), (val)) + 1;

end

audiowrite(outputPath, Z, FS);

end