clear;
%cyclic (7,4)
n = 7;
k = 4;
gen=[1     0     1     1];  %wielomian generujacy dla n = 7 k =4  x^3 + x + 1
msg=[1 1 0 1;
     1 1 1 1;
     1 0 1 1;
     1 1 1 0];
mul = [ 1 0 0 0];    % x^(n-k)
disp('Pakiety');
disp(msg);

%%KODOWANIE PAKIETOW
encodedPcks =zeros(size(msg,1),n);
for i=1:size(msg)
    temp = msg(i,:);
    w = conv(temp,mul);
    [~,r] = deconv(w,gen);
    remAbs = mod(abs(r),2);
    encoded = mod(w+remAbs,2);
    encodedPcks(i,:) = encoded;
end

disp('Zakodowane pakiety:');
disp(encodedPcks);

encodedPcks(1,3) = ~encodedPcks(1,3); % blad na 3 pozycji, TODO generowanie bledów
%%DECODING



disp('Dekodowanie:');

decodedPcks = zeros(size(msg,1),n);
for l=1:size(encodedPcks)
    toDecode = encodedPcks(l,:);
    i = 1;
    while(1)     %% petla while zostaje przerwana, gdy waga syndromu <=1
        [q,r] = deconv(toDecode,gen);
        remAbs = mod(abs(r),2);
        weight = 0;
        for j=1:length(remAbs)
            if(remAbs(1,j) == 1)
                weight = weight +1;
            end
        end
        if(weight<= 1)
            toDecode = toDecode + remAbs;
            toDecode = circshift(mod(abs(toDecode),2), [0,-i+1]);
            decodedPcks(l,:) = toDecode;
            break;
        else
            if(i-1 == k)
                disp("Blad, nie mozna naprawic wiecej niz 1 bledu");
                break
            end
            i = i+1;
            toDecode = circshift(toDecode, [0, 1]);
        end
    end
end

disp(decodedPcks);