refactor(multichain): add getMultichainTypeFromAddress + use it for j…

…azzicon namespace logic

shared/lib/multichain.test.ts

@@ -1,4 +1,9 @@
-import { isBtcMainnetAddress, isBtcTestnetAddress } from './multichain';
+import {
+  MultichainType,
+  getMultichainTypeFromAddress,
+  isBtcMainnetAddress,
+  isBtcTestnetAddress,
+} from './multichain';
 
 const BTC_MAINNET_ADDRESSES = [
   // P2WPKH
@@ -55,4 +60,36 @@ describe('multichain', () => {
       },
     );
   });
+
+  describe('getChainTypeFromAddress', () => {
+    // @ts-expect-error This is missing from the Mocha type definitions
+    it.each([...BTC_MAINNET_ADDRESSES, ...BTC_TESTNET_ADDRESSES])(
+      'returns ChainType.Bitcoin for bitcoin address: %s',
+      (address: string) => {
+        expect(getMultichainTypeFromAddress(address)).toBe(
+          MultichainType.Bip122,
+        );
+      },
+    );
+
+    // @ts-expect-error This is missing from the Mocha type definitions
+    it.each(ETH_ADDRESSES)(
+      'returns ChainType.Ethereum for ethereum address: %s',
+      (address: string) => {
+        expect(getMultichainTypeFromAddress(address)).toBe(
+          MultichainType.Eip155,
+        );
+      },
+    );
+
+    // @ts-expect-error This is missing from the Mocha type definitions
+    it.each(SOL_ADDRESSES)(
+      'returns ChainType.Ethereum for non-supported address: %s',
+      (address: string) => {
+        expect(getMultichainTypeFromAddress(address)).toBe(
+          MultichainType.Eip155,
+        );
+      },
+    );
+  });
 });

shared/lib/multichain.ts

@@ -1,5 +1,15 @@
 import { validate, Network } from 'bitcoin-address-validation';
 
+/**
+ * Multi-chain family type.
+ */
+export enum MultichainType {
+  // Bitcoin-like:
+  Bip122 = 'bip122',
+  // Ethereum:
+  Eip155 = 'eip155',
+}
+
 /**
  * Returns whether an address is on the Bitcoin mainnet.
  *
@@ -26,3 +36,17 @@ export function isBtcMainnetAddress(address: string): boolean {
 export function isBtcTestnetAddress(address: string): boolean {
   return validate(address, Network.testnet);
 }
+
+/**
+ * Returns the associated chain's type for the given address.
+ *
+ * @param address - The address to check.
+ * @returns The chain's type for that address.
+ */
+export function getMultichainTypeFromAddress(address: string): MultichainType {
+  if (isBtcMainnetAddress(address) || isBtcTestnetAddress(address)) {
+    return MultichainType.Bip122;
+  }
+  // Defaults to "Ethereum" for all other cases for now.
+  return MultichainType.Eip155;
+}

ui/components/component-library/avatar-account/avatar-account.tsx

@@ -7,8 +7,8 @@ import type { PolymorphicRef } from '../box';
 
 import { AvatarBase, AvatarBaseProps } from '../avatar-base';
 import {
-  isBtcMainnetAddress,
-  isBtcTestnetAddress,
+  MultichainType,
+  getMultichainTypeFromAddress,
 } from '../../../../shared/lib/multichain';
 import {
   AvatarAccountDiameter,
@@ -18,19 +18,15 @@ import {
   AvatarAccountProps,
 } from './avatar-account.types';
 
-// TODO: This might not scale well with our new multichain initiative since it would require
-// future account's type to be added here too. The best approach might be to use
-// `InternalAccount` type rather than plain addresses. This way we could use the account's
-// type to "infer" the namespace.
-// For now, keep keep this simple.
 function getJazziconNamespace(address: string): string | undefined {
-  if (isBtcMainnetAddress(address) || isBtcTestnetAddress(address)) {
-    // TODO: Add this to @metamask/utils `KnownCaipNamespaces` and use it here:
-    return 'bip122';
+  switch (getMultichainTypeFromAddress(address)) {
+    case MultichainType.Bip122:
+      return 'bip122';
+    case MultichainType.Eip155:
+      return undefined; // Falls back to default Jazzicon behavior
+    default:
+      return undefined;
   }
-  // We leave it `undefined` to fallback to the default jazzicon behavior (even for
-  // ethereum).
-  return undefined;
 }
 
 export const AvatarAccount: AvatarAccountComponent = React.forwardRef(