Doc commit tag conventions

packages/stack/src/wallet/wallet-hd.ts

@@ -29,7 +29,7 @@ import {
   encodeExtendedJson,
 } from '@xocash/primitives';
 
-import { hexToBin } from '@bitauth/libauth';
+import { hash256, binToHex, hexToBin, utf8ToBin } from '@bitauth/libauth';
 
 export const DERIVATION_PATH = "m/44'/145'/0'";
 export const ADDRESS_GAP = 20;
@@ -91,23 +91,6 @@ export class WalletHD<
   // Store child wallets, grouped by chain ("change") path in BIP44 spec.
   public wallets: { [chainPath: number]: Array<WalletType> } = {};
 
-  constructor(
-    public blockchain: BaseBlockchain,
-    public store: BaseStore,
-    public cache: BaseStore,
-    public hdPrivateNode: HDPrivateNode,
-    private walletFactory: WalletP2PKHFactory<WalletType> = useWalletP2PKH,
-  ) {
-    super();
-
-    // Initialize empty arrays for our wallets.
-    this.wallets[CHAIN_EXTERNAL] = [];
-    this.wallets[CHAIN_INTERNAL] = [];
-
-    // Initialize proxies to our stored data.
-    this.genesisData = this.store.proxy('genesis');
-  }
-
   static async from<T extends typeof WalletHD>(
     this: T,
     services: WalletServices,
@@ -166,6 +149,46 @@ export class WalletHD<
     ) as InstanceType<T>;
   }
 
+  constructor(
+    public blockchain: BaseBlockchain,
+    public store: BaseStore,
+    public cache: BaseStore,
+    public hdPrivateNode: HDPrivateNode,
+    private walletFactory: WalletP2PKHFactory<WalletType> = useWalletP2PKH,
+  ) {
+    super();
+
+    // Initialize empty arrays for our wallets.
+    this.wallets[CHAIN_EXTERNAL] = [];
+    this.wallets[CHAIN_INTERNAL] = [];
+
+    // Initialize proxies to our stored data.
+    this.genesisData = this.store.proxy('genesis');
+  }
+
+  async getId() {
+    // NOTE: Use the cache to optimize future calls.
+    return binToHex(
+      await this.cache.getOrSet('walletId', async () =>
+        this.deriveKey('walletId'),
+      ),
+    );
+  }
+
+  async getEncryptionKey() {
+    // NOTE: Use the cache to optimize future calls.
+    return await this.cache.getOrSet('encryptionKey', async () =>
+      this.deriveKey('encryptionKey'),
+    );
+  }
+
+  async getSigningKey() {
+    // NOTE: Use the cache to optimize future calls.
+    return this.cache.getOrSet('signingKey', async () =>
+      this.deriveKey('signingKey'),
+    );
+  }
+
   async start() {
     // Get the genesis data.
     const genesisData = await this.genesisData.getOrFail();
@@ -504,6 +527,19 @@ export class WalletHD<
 
     this.emit('stateUpdated', null);
   }
+
+  protected async deriveKey(keyName: string): Promise<Uint8Array> {
+    // Get the genesis data for this wallet.
+    // TODO: This needs to change!
+    const genesisData = await this.store.getOrFail('genesis');
+
+    // Hash the genesis data using Hash256 and the key ("WalletID") for this derivation using Hash256.
+    const genesisDataHashed = hash256(utf8ToBin(JSON.stringify(genesisData)));
+    const keyHashed = hash256(utf8ToBin(keyName));
+
+    // Combine the hashes and do one final hash for good measure.
+    return hash256(new Uint8Array([...genesisDataHashed, ...keyHashed]));
+  }
 }
 
 //-----------------------------------------------------------------------------