From 642b19bd1b14c5f683df6a18e12bf71d5a86eb89 Mon Sep 17 00:00:00 2001
From: Abhijit Roy <dalvath3700@gmail.com>
Date: Mon, 10 Jun 2024 13:43:10 +0530
Subject: [PATCH] Add blake2_256 function and its tests to auto-utils

---
 packages/auto-utils/__test__/crypto.test.ts | 16 +++++++++++
 packages/auto-utils/src/crypto.ts           | 31 +++++++++++++++++++++
 packages/auto-utils/src/index.ts            |  1 +
 3 files changed, 48 insertions(+)
 create mode 100644 packages/auto-utils/__test__/crypto.test.ts
 create mode 100644 packages/auto-utils/src/crypto.ts

diff --git a/packages/auto-utils/__test__/crypto.test.ts b/packages/auto-utils/__test__/crypto.test.ts
new file mode 100644
index 00000000..8fff6ba9
--- /dev/null
+++ b/packages/auto-utils/__test__/crypto.test.ts
@@ -0,0 +1,16 @@
+import { blake2b_256, stringToUint8Array } from '../src/crypto'
+
+describe('Verify crypto functions', () => {
+  test('Check blake2b_256 return the hash of the data', async () => {
+    const message = 'Alice transfer money to Bob'
+    const data = stringToUint8Array(message)
+    const hash = blake2b_256(data)
+    expect(hash).toMatch('0x')
+  })
+
+  test('Check stringToUint8Array return the byte array of the string', async () => {
+    const message = 'Hello, world!'
+    const byteArray = stringToUint8Array(message)
+    expect(byteArray).toBeInstanceOf(Uint8Array)
+  })
+})
diff --git a/packages/auto-utils/src/crypto.ts b/packages/auto-utils/src/crypto.ts
new file mode 100644
index 00000000..1dce5c74
--- /dev/null
+++ b/packages/auto-utils/src/crypto.ts
@@ -0,0 +1,31 @@
+import { blake2AsHex } from '@polkadot/util-crypto'
+
+/**
+ * Hashes the given data using BLAKE2b-256.
+ *
+ * @param data Uint8Array - The data to be hashed.
+ * @returns string - The BLAKE2b-256 hash of the data as a hex string.
+ */
+export function blake2b_256(data: Uint8Array): string {
+  return blake2AsHex(data, 256)
+}
+
+/**
+ * Converts a string to a Uint8Array using UTF-8 encoding.
+ *
+ * This function uses the TextEncoder API to convert a plain string into its equivalent byte array
+ * representation in UTF-8 format. It is useful for scenarios where string data needs to be processed
+ * in a binary format, such as hashing or cryptographic operations.
+ *
+ * @param text The string to be converted into a byte array.
+ * @returns Uint8Array - The UTF-8 encoded byte array representation of the input string.
+ *
+ * @example
+ * const text = "Hello, world!";
+ * const byteArray = stringToUint8Array(text);
+ * console.log(byteArray); // Outputs the byte array of the string
+ */
+export function stringToUint8Array(text: string): Uint8Array {
+  const encoder = new TextEncoder() // Create a new TextEncoder instance
+  return encoder.encode(text) // Encode the string to a Uint8Array using UTF-8 encoding
+}
diff --git a/packages/auto-utils/src/index.ts b/packages/auto-utils/src/index.ts
index d38eecfc..520949a3 100644
--- a/packages/auto-utils/src/index.ts
+++ b/packages/auto-utils/src/index.ts
@@ -1,4 +1,5 @@
 export * from './api'
+export * from './crypto'
 export * from './network'
 export * from './read'
 export * from './save'