feat: STAKE-822 build your balance component (#11261)

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## **Description**

Added:
- "Staked Ethereum" balance row item to the ETH asset page. This PR is
using mock data until it is connected to the backend. This component
will be hidden via feature flag until it's ready.

<!--
Write a short description of the changes included in this pull request,
also include relevant motivation and context. Have in mind the following
questions:
1. What is the reason for the change?
2. What is the improvement/solution?
-->

## **Related issues**

[STAKE-822: [FE] Build "Your Balance" component
](https://consensyssoftware.atlassian.net/browse/STAKE-822)
## **Manual testing steps**

1. Enable the feature flag by adding `export
MM_POOLED_STAKING_UI_ENABLED=true` to your local `.js.env` file
2. Select Ethereum from the token list
3. You should see the "Staked Ethereum" balance row item, 2 "unstaking
in progress" banners, 1 claim ETH banner, 1 "Unstake", and 1 "Stake
more" button.
4. Clicking the "Stake more" button should open the StakeInputView that
was recently added in a previous PR.

## **Screenshots/Recordings**

<!-- If applicable, add screenshots and/or recordings to visualize the
before and after of your change. -->

### **Before**

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https://github.com/user-attachments/assets/7186c486-d9e1-4005-8467-c3aa72d6d890


### **After**

<!-- [screenshots/recordings] -->

https://github.com/user-attachments/assets/61e91eac-f1b4-40f0-a3ff-26b051ae858f

## **Pre-merge author checklist**

- [x] I’ve followed [MetaMask Contributor
Docs](https://github.com/MetaMask/contributor-docs) and [MetaMask Mobile
Coding
Standards](https://github.com/MetaMask/metamask-mobile/blob/main/.github/guidelines/CODING_GUIDELINES.md).
- [x] I've completed the PR template to the best of my ability
- [x] I’ve included tests if applicable
- [ ] I’ve documented my code using [JSDoc](https://jsdoc.app/) format
if applicable
- [x] I’ve applied the right labels on the PR (see [labeling
guidelines](https://github.com/MetaMask/metamask-mobile/blob/main/.github/guidelines/LABELING_GUIDELINES.md)).
Not required for external contributors.

## **Pre-merge reviewer checklist**

- [ ] I've manually tested the PR (e.g. pull and build branch, run the
app, test code being changed).
- [ ] I confirm that this PR addresses all acceptance criteria described
in the ticket it closes and includes the necessary testing evidence such
as recordings and or screenshots.

app/components/UI/AssetOverview/Balance/Balance.tsx

@@ -26,6 +26,9 @@ import Text, {
 } from '../../../../component-library/components/Texts/Text';
 import { TokenI } from '../../Tokens/types';
 import { useNavigation } from '@react-navigation/native';
+import { isPooledStakingFeatureEnabled } from '../../Stake/constants';
+import StakingBalance from '../../Stake/components/StakingBalance/StakingBalance';
+
 interface BalanceProps {
   asset: TokenI;
   mainBalance: string;
@@ -86,6 +89,7 @@ const Balance = ({ asset, mainBalance, secondaryBalance }: BalanceProps) => {
           {asset.name || asset.symbol}
         </Text>
       </AssetElement>
+      {isPooledStakingFeatureEnabled() && asset?.isETH && <StakingBalance />}
     </View>
   );
 };

app/components/UI/Stake/components/StakingBalance/StakingBalance.styles.ts

@@ -0,0 +1,31 @@
+import { StyleSheet } from 'react-native';
+
+const styleSheet = () =>
+  StyleSheet.create({
+    container: {
+      paddingHorizontal: 16,
+    },
+    badgeWrapper: {
+      alignSelf: 'center',
+    },
+    balances: {
+      flex: 1,
+      justifyContent: 'center',
+      marginLeft: 20,
+      alignSelf: 'center',
+    },
+    ethLogo: {
+      width: 32,
+      height: 32,
+      borderRadius: 16,
+      overflow: 'hidden',
+    },
+    bannerStyles: {
+      marginVertical: 8,
+    },
+    buttonsContainer: {
+      paddingTop: 8,
+    },
+  });
+
+export default styleSheet;

app/components/UI/Stake/components/StakingBalance/StakingBalance.test.tsx

@@ -0,0 +1,50 @@
+import React from 'react';
+import { fireEvent, screen } from '@testing-library/react-native';
+import { renderScreen } from '../../../../../util/test/renderWithProvider';
+import { backgroundState } from '../../../../../util/test/initial-root-state';
+import StakingBalance from './StakingBalance';
+import { strings } from '../../../../../../locales/i18n';
+import Routes from '../../../../../constants/navigation/Routes';
+
+function render(Component: React.ComponentType) {
+  return renderScreen(
+    Component,
+    {
+      name: 'Asset',
+    },
+    {
+      state: {
+        engine: {
+          backgroundState,
+        },
+      },
+    },
+  );
+}
+
+const mockNavigate = jest.fn();
+
+jest.mock('@react-navigation/native', () => {
+  const actualReactNavigation = jest.requireActual('@react-navigation/native');
+  return {
+    ...actualReactNavigation,
+    useNavigation: () => ({
+      navigate: mockNavigate,
+    }),
+  };
+});
+describe('StakingBalance', () => {
+  it('render matches snapshot', () => {
+    render(StakingBalance);
+    expect(screen.toJSON()).toMatchSnapshot();
+  });
+
+  it('redirects to StakeInputView on stake button click', () => {
+    render(StakingBalance);
+
+    fireEvent.press(screen.getByText(strings('stake.stake_more')));
+
+    expect(mockNavigate).toHaveBeenCalledTimes(1);
+    expect(mockNavigate).toHaveBeenCalledWith(Routes.STAKE.STAKE);
+  });
+});

app/components/UI/Stake/components/StakingBalance/StakingBalance.tsx

@@ -0,0 +1,189 @@
+import React, { useMemo, useState } from 'react';
+import Badge, {
+  BadgeVariant,
+} from '../../../../../component-library/components/Badges/Badge';
+import BadgeWrapper from '../../../../../component-library/components/Badges/BadgeWrapper';
+import Text, {
+  TextVariant,
+} from '../../../../../component-library/components/Texts/Text';
+import { useStyles } from '../../../../../component-library/hooks';
+import AssetElement from '../../../AssetElement';
+import NetworkMainAssetLogo from '../../../NetworkMainAssetLogo';
+import { selectNetworkName } from '../../../../../selectors/networkInfos';
+import { useSelector } from 'react-redux';
+import images from '../../../../../images/image-icons';
+import styleSheet from './StakingBalance.styles';
+import { View } from 'react-native';
+import StakingButtons from './StakingButtons/StakingButtons';
+import ClaimBanner from './StakingBanners/ClaimBanner/ClaimBanner';
+import UnstakingBanner from './StakingBanners/UnstakeBanner/UnstakeBanner';
+import Banner, {
+  BannerAlertSeverity,
+  BannerVariant,
+} from '../../../../../component-library/components/Banners/Banner';
+import { strings } from '../../../../../../locales/i18n';
+import { renderFromWei } from '../../../../../util/number';
+import { GetStakesApiResponse } from './StakingBalance.types';
+import { TokenI } from '../../../../UI/Tokens/types';
+import { getTimeDifferenceFromNow } from '../../../../../util/date';
+import { filterExitRequests } from './utils';
+import { BN } from 'ethereumjs-util';
+import bn from 'bignumber.js';
+import { fixDisplayAmount } from '../../utils/value';
+import { multiplyValueByPowerOfTen } from '../../utils/bignumber';
+
+// TODO: Replace mock data when connecting to backend.
+const MOCK_STAKED_ETH_ASSET = {
+  balance: '4.9999 ETH',
+  balanceFiat: '$13,292.20',
+  name: 'Staked Ethereum',
+  symbol: 'ETH',
+} as TokenI;
+
+// TODO: Replace mock data when connecting to backend.
+const MOCK_UNSTAKING_REQUESTS: GetStakesApiResponse = {
+  accounts: [
+    {
+      account: '0x0123456789abcdef0123456789abcdef01234567',
+      lifetimeRewards: '43927049303048',
+      assets: '17913326707142320',
+      exitRequests: [
+        {
+          // Unstaking
+          positionTicket: '2153260738145148336740',
+          timestamp: '1727110415000',
+          totalShares: '989278156820374',
+          withdrawalTimestamp: null,
+          exitQueueIndex: '-1',
+          claimedAssets: null,
+          leftShares: null,
+        },
+        // Requests below are claimable.
+        {
+          positionTicket: '515964521392314631201',
+          timestamp: '1720539311000',
+          totalShares: '99473618267007',
+          withdrawalTimestamp: '0',
+          exitQueueIndex: '57',
+          claimedAssets: '100006626507361',
+          leftShares: '0',
+        },
+        {
+          positionTicket: '515964620865932898208',
+          timestamp: '1720541495000',
+          totalShares: '99473618267007',
+          withdrawalTimestamp: '0',
+          exitQueueIndex: '57',
+          claimedAssets: '100006626507361',
+          leftShares: '0',
+        },
+        {
+          positionTicket: '516604671289934191921',
+          timestamp: '1720607327000',
+          totalShares: '1929478758729790',
+          withdrawalTimestamp: '0',
+          exitQueueIndex: '58',
+          claimedAssets: '1939870510970987',
+          leftShares: '0',
+        },
+      ],
+    },
+  ],
+  exchangeRate: '1.010906701603882254',
+};
+
+const StakingBalance = () => {
+  const { styles } = useStyles(styleSheet, {});
+
+  const networkName = useSelector(selectNetworkName);
+
+  const [isGeoBlocked] = useState(true);
+
+  const { unstakingRequests, claimableRequests } = useMemo(
+    () =>
+      filterExitRequests(
+        MOCK_UNSTAKING_REQUESTS.accounts[0].exitRequests,
+        MOCK_UNSTAKING_REQUESTS.exchangeRate,
+      ),
+    [],
+  );
+
+  const claimableEth = useMemo(
+    () =>
+      renderFromWei(
+        claimableRequests.reduce(
+          (acc, { claimedAssets }) =>
+            claimedAssets ? acc.add(new BN(claimedAssets)) : acc,
+          new BN(0),
+        ),
+      ),
+    [claimableRequests],
+  );
+
+  const hasClaimableEth = !!Number(claimableEth);
+
+  return (
+    <View>
+      <AssetElement
+        asset={MOCK_STAKED_ETH_ASSET}
+        mainBalance={MOCK_STAKED_ETH_ASSET.balance}
+        balance={MOCK_STAKED_ETH_ASSET.balanceFiat}
+      >
+        <BadgeWrapper
+          style={styles.badgeWrapper}
+          badgeElement={
+            <Badge
+              variant={BadgeVariant.Network}
+              imageSource={images.ETHEREUM}
+              name={networkName}
+            />
+          }
+        >
+          <NetworkMainAssetLogo style={styles.ethLogo} />
+        </BadgeWrapper>
+        <Text style={styles.balances} variant={TextVariant.BodyLGMedium}>
+          {MOCK_STAKED_ETH_ASSET.name || MOCK_STAKED_ETH_ASSET.symbol}
+        </Text>
+      </AssetElement>
+      <View style={styles.container}>
+        {unstakingRequests.map(
+          ({ positionTicket, withdrawalTimestamp, assetsToDisplay }) =>
+            assetsToDisplay && (
+              <UnstakingBanner
+                key={positionTicket}
+                amountEth={fixDisplayAmount(
+                  multiplyValueByPowerOfTen(new bn(assetsToDisplay), -18),
+                  4,
+                )}
+                timeRemaining={
+                  !Number(withdrawalTimestamp)
+                    ? { days: 11, hours: 0, minutes: 0 } // default to 11 days.
+                    : getTimeDifferenceFromNow(Number(withdrawalTimestamp))
+                }
+                style={styles.bannerStyles}
+              />
+            ),
+        )}
+        {hasClaimableEth && (
+          <ClaimBanner
+            claimableAmount={claimableEth}
+            style={styles.bannerStyles}
+          />
+        )}
+        {isGeoBlocked && (
+          <Banner
+            variant={BannerVariant.Alert}
+            severity={BannerAlertSeverity.Warning}
+            description={strings('stake.banner_text.geo_blocked')}
+            style={styles.bannerStyles}
+          />
+        )}
+        <View style={styles.buttonsContainer}>
+          <StakingButtons />
+        </View>
+      </View>
+    </View>
+  );
+};
+
+export default StakingBalance;

app/components/UI/Stake/components/StakingBalance/StakingBalance.types.ts

@@ -0,0 +1,38 @@
+export interface ExitRequest {
+  positionTicket: string; // BigInt!
+  timestamp: string; // BigInt!
+  totalShares: string; // BigInt!
+  receiver: string; // Bytes!
+  /**
+   * If `withdrawalTimestamp` is null, it means the request hasn't been processed yet.
+   * If `withdrawalTimestamp` is "0", funds are withdrawable.
+   * Else, `withdrawalTimestamp` shows an approximate UTC timestamp of when funds will be withdrawable.
+   * `withdrawalTimestamp` is updated every 6 hours.
+   */
+  withdrawalTimestamp: string | null; // BigInt
+}
+
+export type ExitRequestWithClaimedAssetInfo = Pick<
+  ExitRequest,
+  'positionTicket' | 'timestamp' | 'totalShares' | 'withdrawalTimestamp'
+> & {
+  exitQueueIndex: string;
+  claimedAssets: string | null;
+  leftShares: string | null;
+};
+
+interface StakeByAccount {
+  account: string;
+  lifetimeRewards: string;
+  assets: string;
+  exitRequests: ExitRequestWithClaimedAssetInfo[];
+}
+
+export interface GetStakesApiResponse {
+  accounts: StakeByAccount[];
+  exchangeRate: string;
+}
+
+export interface UnstakingRequest extends ExitRequestWithClaimedAssetInfo {
+  assetsToDisplay: string;
+}

app/components/UI/Stake/components/StakingBalance/StakingBanners/ClaimBanner/ClaimBanner.styles.ts

@@ -0,0 +1,10 @@
+import { StyleSheet } from 'react-native';
+
+const styleSheet = () =>
+  StyleSheet.create({
+    claimButton: {
+      alignSelf: 'flex-start',
+    },
+  });
+
+export default styleSheet;