harb/web-app/AGENTS.md

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# Web App - Agent Guide

Vue 3 + TypeScript staking interface for KRAIKEN, enabling users to stake tokens, manage positions, and interact with Harberger-tax mechanics.

## Technology Snapshot
- Vue 3 (Composition API) with TypeScript and Vite toolchain
- Wagmi/Viem for wallet connection and blockchain interaction
- Vue Router for navigation
- Axios for GraphQL queries to Ponder indexer
- Sass-based component styling

## Architecture

### Chain Configuration
`src/services/chainConfig.ts` centralizes endpoint resolution. All composables accept `chainId` as a parameter and resolve endpoints via `chainConfigService.getEndpoint(chainId, type)`. Supported chains: 31337 (Anvil), 84532 (Base Sepolia), 8453 (Base Mainnet).

### Wagmi Integration
`src/wagmi.ts` manages wallet connection. Wagmi is the source of truth for which chain the wallet is on. Composables don't import wallet state directly — they accept `chainId` for testability.

### Key Composables
- `useWallet()` — Wallet connection, balance, account state
- `usePositions(chainId)` — Loads staking positions from Ponder GraphQL
- `useStatCollection(chainId)` — Protocol-wide statistics
- `useSnatchSelection(demo, taxRateIndex, chainId)` — Calculates snatchable positions
- `useStake()` — Executes staking transactions
- `useAdjustTaxRate()` — Tax rate adjustment
- `useUnstake()` — Position exit transactions

### Key Components
- `StakeView.vue` — Main staking dashboard (route: `/dashboard`)
- `StakeHolder.vue` — Staking form with accessibility-focused UI
- `ConnectWallet.vue` — Wallet connection modal
- `ChartComplete.vue` — Position visualization
- `CollapseActive.vue` — Expandable position card with actions

## Development Workflow
- Boot full stack: `./scripts/dev.sh start` (see root AGENTS.md)
- Targeted: `npm run dev` (assumes Ponder/Anvil already running)
- Build: `npm run build`
- E2E tests: `npm run test:e2e` from repo root (Playwright)

## Testing
- E2E tests in `tests/e2e/` (repo root) cover complete user journeys
- Uses mocked wallet provider with Anvil accounts
- Relies on semantic HTML and ARIA attributes for selectors
- StakeHolder test hooks: `page.getByRole('slider', { name: 'Token Amount' })`, `page.getByLabel('Tax')`

## Analytics

The web app uses `@harb/analytics` (self-hosted Umami wrapper) for funnel event tracking. `initAnalytics(VITE_UMAMI_URL, VITE_UMAMI_WEBSITE_ID)` is called in `main.ts`. Tracked events:

| Event | Where | Helper |
|-------|-------|--------|
| `wallet_connect` | `useWallet.ts` — on first address set | `trackWalletConnect()` |
| `swap_initiated` | `useSwapKrk.ts` — before buy/sell tx | `trackSwapInitiated('buy'\|'sell')` |
| `stake_created` | `useStake.ts` — after PositionCreated event | `trackStakeCreated()` |

All calls are silent no-ops if Umami is unavailable. Env vars: `VITE_UMAMI_URL`, `VITE_UMAMI_WEBSITE_ID`.

## Quality Guidelines
- Composables accept `chainId` parameter instead of importing wallet state directly
- Each composable maintains its own `watchChainId()` listener for independence
- Always expose `xxxError` and `loading` refs for UI feedback
- Use strongly typed interfaces for Position, StatsRecord, etc.
- Use semantic HTML, ARIA attributes, and keyboard navigation
- Clear watchers and retry timers in `onUnmounted()`