# AGENTS.md - AI Coding Agent Guidelines

Guidelines for AI agents working in this Bun monorepo.

## Project Overview

- **Monorepo**: Bun workspaces + Turborepo orchestration
- **Runtime**: Bun (see `mise.toml` for version)
- **Apps**:
  - `apps/server` - TanStack Start fullstack web app (see `apps/server/AGENTS.md`)
  - `apps/desktop` - Tauri v2 desktop shell, loads server via sidecar (see `apps/desktop/AGENTS.md`)
- **Packages**: `packages/utils`, `packages/tsconfig` (shared configs)

## Build / Lint / Test Commands

### Root Commands (via Turbo)
```bash
bun dev            # Start all apps in dev mode
bun build          # Build all apps
bun fix            # Lint + format (Biome auto-fix)
bun typecheck      # TypeScript check across monorepo
```

### Server App (`apps/server`)
```bash
bun dev                   # Vite dev server (localhost:3000)
bun build                 # Production build → .output/
bun fix                   # Biome auto-fix
bun typecheck             # TypeScript check

# Database (Drizzle)
bun db:generate           # Generate migrations from schema
bun db:migrate            # Run migrations
bun db:push               # Push schema (dev only)
bun db:studio             # Open Drizzle Studio
```

### Desktop App (`apps/desktop`)
```bash
bun dev                   # Copy sidecar + start Tauri dev
bun build                 # Copy sidecar + build installer

# Rust (from apps/desktop/src-tauri/)
cargo check               # Compile check
cargo clippy              # Linter
cargo fmt                 # Formatter
```

### Testing
No test framework configured yet. When adding tests:
```bash
bun test path/to/test.ts              # Run single test file
bun test -t "pattern"                 # Run tests matching pattern
cargo test test_name -- --nocapture   # Rust single test with output
```

## Code Style (TypeScript)

### Formatting (Biome)
- **Indent**: 2 spaces
- **Line endings**: LF
- **Quotes**: Single `'`
- **Semicolons**: Omit (ASI)
- **Arrow parentheses**: Always `(x) => x`

### Imports
Biome auto-organizes. Order:
1. External packages
2. Internal `@/*` aliases
3. Type imports (`import type { ... }`)

```typescript
import { createFileRoute } from '@tanstack/react-router'
import { z } from 'zod'
import { db } from '@/server/db'
import type { ReactNode } from 'react'
```

### TypeScript Strictness
- `strict: true`
- `noUncheckedIndexedAccess: true` - array/object access returns `T | undefined`
- `noImplicitOverride: true`
- `verbatimModuleSyntax: true`
- Use `@/*` path aliases (maps to `src/*`)

### Naming Conventions
| Type | Convention | Example |
|------|------------|---------|
| Files (utils) | kebab-case | `auth-utils.ts` |
| Files (components) | PascalCase | `UserProfile.tsx` |
| Components | PascalCase arrow | `const Button = () => {}` |
| Functions | camelCase | `getUserById` |
| Constants | UPPER_SNAKE | `MAX_RETRIES` |
| Types/Interfaces | PascalCase | `UserProfile` |

### React Patterns
```typescript
// Components: arrow functions (enforced by Biome)
const MyComponent = ({ title }: { title: string }) => {
  return <div>{title}</div>
}

// Routes: TanStack Router file conventions
export const Route = createFileRoute('/')({
  component: Home,
})

// Data fetching: TanStack Query
const { data } = useSuspenseQuery(orpc.todo.list.queryOptions())
```

### Error Handling
- Use `try-catch` for async operations
- Throw descriptive errors
- ORPC: Use `ORPCError` with proper codes (`NOT_FOUND`, `INPUT_VALIDATION_FAILED`)
- Never use empty catch blocks

## Code Style (Rust - Tauri)

- **Indent**: 4 spaces
- **Naming**: snake_case (functions), PascalCase (types), SCREAMING_SNAKE (consts)
- Use `expect("中文消息")` over `unwrap()`
- Async: `tokio` runtime, `tauri::async_runtime::spawn`
- Run `cargo fmt` and `cargo clippy` before commit

## Database (Drizzle ORM)

```typescript
import { pgTable, text, timestamp, uuid } from 'drizzle-orm/pg-core'
import { sql } from 'drizzle-orm'

export const myTable = pgTable('my_table', {
  id: uuid().primaryKey().default(sql`uuidv7()`),
  name: text().notNull(),
  createdAt: timestamp({ withTimezone: true }).notNull().defaultNow(),
  updatedAt: timestamp({ withTimezone: true }).notNull().defaultNow().$onUpdateFn(() => new Date()),
})
```

## Environment Variables

- Use `@t3-oss/env-core` with Zod validation in `src/env.ts`
- Server vars: no prefix
- Client vars: `VITE_` prefix required
- Never commit `.env` files

## Critical Rules

**DO:**
- Run `bun fix` before committing
- Use `@/*` path aliases (not relative imports)
- Let React Compiler handle memoization (no manual `useMemo`/`useCallback`)
- Include `createdAt`/`updatedAt` on all tables

**DON'T:**
- Edit `src/routeTree.gen.ts` (auto-generated)
- Use `as any`, `@ts-ignore`, `@ts-expect-error`
- Commit `.env` files
- Use empty catch blocks `catch(e) {}`
- Use `unwrap()` in Rust without `expect()`

## Git Workflow

1. Make changes following style guide
2. `bun fix` - auto-format and lint
3. `bun typecheck` - verify types
4. `bun dev` - test locally
5. Commit with descriptive message

## Directory Structure

```
.
├── apps/
│   ├── server/           # TanStack Start fullstack app
│   │   ├── src/
│   │   │   ├── client/   # ORPC client, Query client
│   │   │   ├── components/
│   │   │   ├── routes/   # File-based routing
│   │   │   └── server/   # API layer + database
│   │   │       ├── api/  # ORPC contracts, routers, middlewares
│   │   │       └── db/   # Drizzle schema
│   │   └── AGENTS.md
│   └── desktop/          # Tauri v2 shell (no frontend src)
│       ├── src-tauri/    # Rust Tauri code
│       │   ├── src/      # Rust source
│       │   └── binaries/ # Sidecar binaries
│       └── AGENTS.md
├── packages/
│   ├── tsconfig/         # Shared TS configs
│   └── utils/            # Shared utilities
├── biome.json            # Linting/formatting config
├── turbo.json            # Turbo task orchestration
└── package.json          # Workspace root
```

## See Also

- `apps/server/AGENTS.md` - Detailed TanStack Start / ORPC patterns
- `apps/desktop/AGENTS.md` - Rust / Tauri development guide