1 files changed, 89 insertions, 0 deletions
diff --git a/kittybox-rs/companion-lite/src/base64.ts b/kittybox-rs/companion-lite/src/base64.ts
new file mode 100644
index 0000000..2429894
--- /dev/null
+++ b/kittybox-rs/companion-lite/src/base64.ts
@@ -0,0 +1,89 @@
+// Array of bytes to Base64 string decoding
+function b64ToUint6(nChr: number) {
+  return nChr > 64 && nChr < 91
+    ? nChr - 65
+    : nChr > 96 && nChr < 123
+    ? nChr - 71
+    : nChr > 47 && nChr < 58
+    ? nChr + 4
+    : nChr === 43
+    ? 62
+    : nChr === 47
+    ? 63
+    : 0;
+}
+
+export function decode(sBase64: string, nBlocksSize?: number) {
+  const sB64Enc = sBase64.replace(/[^A-Za-z0-9+/]/g, "");
+  const nInLen = sB64Enc.length;
+  const nOutLen = nBlocksSize
+    ? Math.ceil(((nInLen * 3 + 1) >> 2) / nBlocksSize) * nBlocksSize
+    : (nInLen * 3 + 1) >> 2;
+  const taBytes = new Uint8Array(nOutLen);
+
+  let nMod3;
+  let nMod4;
+  let nUint24 = 0;
+  let nOutIdx = 0;
+  for (let nInIdx = 0; nInIdx < nInLen; nInIdx++) {
+    nMod4 = nInIdx & 3;
+    nUint24 |= b64ToUint6(sB64Enc.charCodeAt(nInIdx)) << (6 * (3 - nMod4));
+    if (nMod4 === 3 || nInLen - nInIdx === 1) {
+      nMod3 = 0;
+      while (nMod3 < 3 && nOutIdx < nOutLen) {
+        taBytes[nOutIdx] = (nUint24 >>> ((16 >>> nMod3) & 24)) & 255;
+        nMod3++;
+        nOutIdx++;
+      }
+      nUint24 = 0;
+    }
+  }
+
+  return taBytes;
+}
+
+/* Base64 string to array encoding */
+function uint6ToB64(nUint6: number) {
+  return nUint6 < 26
+    ? nUint6 + 65
+    : nUint6 < 52
+    ? nUint6 + 71
+    : nUint6 < 62
+    ? nUint6 - 4
+    : nUint6 === 62
+    ? 43
+    : nUint6 === 63
+    ? 47
+    : 65;
+}
+
+export function encode(aBytes: Uint8Array) {
+  let nMod3 = 2;
+  let sB64Enc = "";
+
+  const nLen = aBytes.length;
+  let nUint24 = 0;
+  for (let nIdx = 0; nIdx < nLen; nIdx++) {
+    nMod3 = nIdx % 3;
+    if (nIdx > 0 && ((nIdx * 4) / 3) % 76 === 0) {
+      sB64Enc += "\r\n";
+    }
+
+    nUint24 |= aBytes[nIdx] << ((16 >>> nMod3) & 24);
+    if (nMod3 === 2 || aBytes.length - nIdx === 1) {
+      sB64Enc += String.fromCodePoint(
+        uint6ToB64((nUint24 >>> 18) & 63),
+        uint6ToB64((nUint24 >>> 12) & 63),
+        uint6ToB64((nUint24 >>> 6) & 63),
+        uint6ToB64(nUint24 & 63)
+      );
+      nUint24 = 0;
+    }
+  }
+  return (
+    sB64Enc.substr(0, sB64Enc.length - 2 + nMod3) +
+      (nMod3 === 2 ? "" : nMod3 === 1 ? "=" : "==")
+  );
+}
+
+export default { encode, decode }