feat: ibc-hooks add derive function

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@terra-money/feather.js",
-  "version": "2.0.0-beta.12",
+  "version": "2.0.0-beta.13",
   "description": "The JavaScript SDK for Terra and Feather chains",
   "license": "MIT",
   "author": "Terraform Labs, PTE.",

src/core/ibc-hooks/helpers/derive-sender.spec.ts

@@ -0,0 +1,51 @@
+import { deriveIbcHooksSender } from './derive-sender';
+
+describe('Must use DeriveIbcHooksSender to derive', () => {
+  it('a terra address successfully for channel-0 and prefix terra', () => {
+    const derived = deriveIbcHooksSender(
+      'channel-0',
+      'terra18qq9svm5tjywcysd549tzkk3ax04f43zml9xay',
+      'terra'
+    );
+
+    expect(derived).toStrictEqual(
+      'terra1qxyr66gyd6fjlr0826cce8fj4jg96hd5jdkg4e3e2hc3gl0r9zps9sc93t'
+    );
+  });
+
+  it('a terra address successfully for channel-1 and prefix terra', () => {
+    const derived = deriveIbcHooksSender(
+      'channel-1',
+      'terra18qq9svm5tjywcysd549tzkk3ax04f43zml9xay',
+      'terra'
+    );
+
+    expect(derived).toStrictEqual(
+      'terra1tdx2llx7dxp245p32rl5xf85qtfhnsn477fs6man34lthdcmr6wsxntykd'
+    );
+  });
+
+  it('a terra address successfully for channel-1 and prefix juno', () => {
+    const derived = deriveIbcHooksSender(
+      'channel-0',
+      'terra18qq9svm5tjywcysd549tzkk3ax04f43zml9xay',
+      'juno'
+    );
+
+    expect(derived).toStrictEqual(
+      'juno1qxyr66gyd6fjlr0826cce8fj4jg96hd5jdkg4e3e2hc3gl0r9zpsrpuvys'
+    );
+  });
+
+  it('a juno address successfully for channel-0 and prefix terra', () => {
+    const derived = deriveIbcHooksSender(
+      'channel-0',
+      'juno1yd8m9u8gexcjectscrduxmtw60psndqhcd87jt',
+      'terra'
+    );
+
+    expect(derived).toStrictEqual(
+      'terra1njxpjzu233h4ctlsyvqq4nuxl5y5cu9lxuprnqmv574ddqkqu7zqxg6u3k'
+    );
+  });
+});

src/core/ibc-hooks/helpers/derive-sender.ts

@@ -0,0 +1,43 @@
+import { AccAddress } from '../../../core/bech32';
+import { bech32 } from 'bech32';
+import { createHash } from 'crypto';
+
+const senderPrefix = 'ibc-wasm-hook-intermediary';
+
+// Function used to derive the counterparty chain address from the
+// ibc channel, originSender and bech32prefix, for ibc-hooks.
+//
+// This function is ported to JS from the following Go code:
+// https://github.com/cosmos/ibc-apps/blob/main/modules/ibc-hooks/keeper/keeper.go#L57-L62
+export const deriveIbcHooksSender = (
+  channel: string,
+  originSender: AccAddress,
+  bech32Prefix: string
+): AccAddress => {
+  const concatedAddress = `${channel}/${originSender}`;
+  const senderSHA256 = hash(senderPrefix, Buffer.from(concatedAddress));
+  const words = bech32.toWords(senderSHA256);
+
+  return bech32.encode(bech32Prefix, words).toString();
+};
+
+// private function to derive the string hash,
+// bassed on the following Go code:
+// https://github.com/cosmos/cosmos-sdk/blob/release/v0.47.x/types/address/hash.go#L26-L39
+const hash = (typ: string, key: Buffer): Buffer => {
+  let hasher = createHash('sha256');
+
+  // Convert the string to a Buffer
+  const typeBuffer = Buffer.from(typ, 'utf-8');
+
+  // First hash
+  hasher.update(typeBuffer);
+  const th = hasher.digest();
+  hasher = createHash('sha256');
+
+  // Reset the hasher and do the second hash
+  hasher.update(th);
+  hasher.update(key);
+
+  return hasher.digest();
+};

src/core/ibc-hooks/index.ts

@@ -0,0 +1 @@
+export * from './helpers/derive-sender';