wip: big refactor

HammingEncoding.js

@@ -0,0 +1,53 @@
+// Encoding to encode/decode data with Hamming Error Correction
+export const DECODED_SIZE = 4;
+export const ENCODED_SIZE = 7;
+
+export const blockSize = () => ({
+  encoded: ENCODED_SIZE,
+  decoded: DECODED_SIZE
+});
+
+export const encode = (bits) => {
+  const encodedBits = [];
+  for(let i = 0; i < bits.length; i+= DECODED_SIZE) {
+    const block = bits.slice(i, i + DECODED_SIZE);
+    encodedBits.push(...encodeBlock(block));
+  }
+  return encodedBits;
+}
+export const decode = bits => {
+  const decodedBits = [];
+  for(let i = 0; i < bits.length; i += ENCODED_SIZE) {
+    const block = bits.slice(i, i + ENCODED_SIZE);
+    decodedBits.push(...decodeBlock(block));
+  }
+  return decodedBits;
+}
+
+const encodeBlock = bits => {
+  if(bits.length !== DECODED_SIZE) return [];
+  return [
+    bits[0] ^ bits[1] ^ bits[3],
+    bits[0] ^ bits[2] ^ bits[3],
+    bits[0],
+    bits[1] ^ bits[2] ^ bits[3],
+    bits[1],
+    bits[2],
+    bits[3]
+  ]
+}
+
+const decodeBlock = bits => {
+  if(bits.length !== ENCODED_SIZE) return [];
+  const error_1 = bits[0] ^ bits[2] ^ bits[4] ^ bits[6];
+  const error_2 = bits[1] ^ bits[2] ^ bits[5] ^ bits[6];
+  const error_3 = bits[3] ^ bits[4] ^ bits[5] ^ bits[6];
+  let error = (error_3 << 2) | (error_2 << 1) | error_1;
+  if(error !== 0) bits[error - 1] ^= 1;
+  return [
+    bits[2],
+    bits[4],
+    bits[5],
+    bits[6]
+  ];
+}