1 files changed, 95 insertions, 0 deletions
diff --git a/apps/web/server/encrypt.ts b/apps/web/server/encrypt.ts
new file mode 100644
index 00000000..bb2f5050
--- /dev/null
+++ b/apps/web/server/encrypt.ts
@@ -0,0 +1,95 @@
+function convertStringToFixedNumber(input: string): number {
+  let hash = 0;
+  for (let i = 0; i < input.length; i++) {
+    const char = input.charCodeAt(i);
+    hash = (hash * 31 + char) % 1000000007; // Hashing by a large prime number
+  }
+  return hash;
+}
+
+const chars = `abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ-1234567890`;
+const shuffled = shuffle(
+  chars.split(""),
+  convertStringToFixedNumber(process.env.BACKEND_SECURITY_KEY),
+);
+
+function random(seed: number) {
+  const x = Math.sin(seed++) * 10000;
+  return x - Math.floor(x);
+}
+
+function shuffle(array: string[], seed: number) {
+  let m = array.length,
+    t,
+    i;
+
+  while (m) {
+    i = Math.floor(random(seed) * m--);
+
+    t = array[m];
+    array[m] = array[i]!;
+    array[i] = t!;
+    ++seed;
+  }
+
+  return array;
+}
+
+export const cipher = (text: string) => {
+  let returned_text = "";
+
+  for (let i = 0; i < text.length; i++) {
+    returned_text += shuffled[chars.indexOf(text[i]!)];
+  }
+
+  return extend(returned_text);
+};
+
+export const decipher = (text: string) => {
+  let returned_text = "";
+  const index = Math.floor(
+    random(convertStringToFixedNumber(process.env.BACKEND_SECURITY_KEY)) *
+      (text.length / 2),
+  );
+
+  for (let i = 0; i < text.length; i++) {
+    returned_text += chars[shuffled.indexOf(text[i]!)];
+  }
+  const total = parseInt(text[index]!);
+  const str = parseInt(text.slice(index + 1, index + total + 1));
+  return returned_text.slice(text.length - str);
+};
+
+const extend = (text: string, length = 60) => {
+  const extra = length - text.length;
+
+  if (extra < 0) {
+    return text;
+  }
+
+  // Random index to store the length of the string
+  const index = Math.floor(
+    random(convertStringToFixedNumber(process.env.BACKEND_SECURITY_KEY)) *
+      (length / 2),
+  );
+
+  const storage_string =
+    text.length.toString().length.toString() + text.length.toString();
+  let returned = "";
+  let total = storage_string.length + text.length;
+
+  for (let i = 0; i < extra; i++) {
+    if (i == index) {
+      returned += storage_string;
+    } else {
+      if (total >= length) {
+        break;
+      }
+      // Add a random character
+      returned += shuffled[Math.floor(random(Math.random()) * shuffled.length)];
+      total++;
+    }
+  }
+  returned += text;
+  return returned;
+};