Resolve "WIP: UTXO Selection and Storage"

packages/stack/src/utils/uuid.ts

@@ -0,0 +1,31 @@
+export function generateUUIDV7(customTimestamp?: bigint) {
+  // Step 1: Get the current timestamp in milliseconds
+  const timestamp = customTimestamp ?? BigInt(Date.now()); // Use BigInt to handle 48-bit values
+
+  // Step 2: Convert the timestamp to a 48-bit hexadecimal string
+  const timestampHex = timestamp.toString(16).padStart(12, '0'); // Ensure 12 hex characters
+
+  // Step 3: Generate 74 bits (19 hex characters) of random data
+  const randomHex = crypto
+    .getRandomValues(new Uint8Array(10))
+    .map((b) => Number(b.toString(16).padStart(2, '0')))
+    .join(''); // 10 bytes = 20 hex characters
+
+  // Step 4: Combine fields to form the UUID
+  const version = '7'; // Version 7 (0111)
+  const variant = '8'; // Variant 1 (10xx) is "8", "9", "a", or "b"
+
+  return (
+    `${timestampHex.substring(0, 8)}-${timestampHex.substring(8, 12)}` + // Timestamp (48 bits)
+    `-${version}${randomHex.substring(0, 3)}` + // Version (4 bits) + 12 random bits
+    `-${variant}${randomHex.substring(3, 6)}` + // Variant (2 bits) + 14 random bits
+    `-${randomHex.substring(6)}` // Remaining 48 random bits
+  );
+}
+
+/**
+ * Extract the timestamp from a UUID v7
+ */
+export function getTimestampFromUUID(uuid: string): bigint {
+  return BigInt(parseInt(uuid.slice(0, 8), 16));
+}