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+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+This is an HRMS (Human Resource Management System) check-in/check-out web application built for the Bangkok Metropolitan Administration (BMA). The application allows employees to record their work attendance using geolocation verification and camera features.
+
+**Tech Stack:**
+- Vue 3 with Composition API and TypeScript
+- Vite for build tooling
+- Quasar Framework for UI components
+- Pinia for state management
+- Vue Router for routing
+- Keycloak for authentication
+- ArcGIS API and Google Maps for location features
+- PWA capabilities with offline support
+- Docker deployment with nginx
+
+**Development Server:** Runs on port 3008
+
+## Common Commands
+
+```bash
+# Development
+npm run dev                    # Start dev server on port 3008
+
+# Building
+npm run build                  # Build for production
+npm run preview                # Preview production build on port 3008
+
+# Testing
+npm run test:unit              # Run unit tests with vitest
+npm run test:e2e               # Run e2e tests with cypress
+npm run test:e2e:dev           # Run cypress in dev mode
+
+# Code Quality
+npm run lint                   # Lint and auto-fix code
+npm run format                 # Format code with prettier
+npm run type-check             # TypeScript type checking
+
+# Docker
+docker buildx build --platform=linux/amd64 -f docker/Dockerfile . -t hrms-checkin:0.1
+```
+
+## Architecture
+
+### Directory Structure
+
+```
+src/
+├── api/               # API layer modules (checkin, history, message)
+├── components/        # Reusable Vue components
+├── composables/       # Vue composables (e.g., usePermissions)
+├── interface/         # TypeScript type definitions
+│   └── response/      # API response types
+├── plugins/           # Vue plugins (auth, http, keycloak)
+├── router/            # Vue Router configuration
+├── stores/            # Pinia stores for state management
+├── style/             # Global styles and Quasar variables
+├── utils/             # Utility functions
+└── views/             # Page-level Vue components
+```
+
+### Key Architecture Patterns
+
+**Authentication Flow:**
+- Uses Keycloak for SSO authentication
+- Tokens stored in cookies with `BMAHRISCKI_KEYCLOAK_IDENTITY` key
+- Auth state managed in `src/plugins/auth.ts`
+- Router guards enforce authentication on protected routes
+- 401 responses trigger automatic logout via axios interceptor
+
+**State Management:**
+- `stores/mixin.ts` - Global utilities (Thai date formatting, dialogs, loaders, error handling)
+- `stores/chekin.ts` - Check-in history and status management
+- `stores/privacy.ts` - Privacy consent management
+- `stores/positionKeycloak.ts` - User position/role data
+
+**API Layer:**
+- Base axios instance in `src/plugins/http.ts` with automatic token injection
+- API endpoints organized by feature in `src/api/`
+- Environment-specific API URLs configured in `src/api/index.ts`
+- Production API URL set via `VITE_API_URI_CONFIG` env variable
+
+**Routing:**
+- Main layout (`MainView`) wraps authenticated routes
+- Protected routes require `meta.Auth: true`
+- Auth check runs in router beforeEach guard
+- Public routes: `/login`, `/auth`, `/reset-password`, `/history`
+
+**Geolocation & Maps:**
+- ArcGIS JS API for advanced mapping features
+- Google Maps integration for location services
+- Camera integration for check-in photo verification
+- Privacy consent required before accessing camera/location
+
+**Date/Time Handling:**
+- Thai Buddhist calendar (BE) conversion (+543 years)
+- Thai month names (full and abbreviated)
+- `date-fns-tz` for timezone handling (Asia/Bangkok)
+- Fiscal year calculation (October start)
+
+### Component Conventions
+
+- Components use Quasar UI components (`q-btn`, `q-dialog`, etc.)
+- Thai language throughout the UI
+- Custom dialogs use `CustomDialog.vue` component
+- Loading states use Quasar's `QSpinnerCube`
+- Error dialogs prevent overlap with `activeErrorDialog` tracking
+
+### Localization
+
+- Quasar configured with Thai language (`quasar/lang/th`)
+- All UI text in Thai
+- Date formatting uses `date2Thai()` and `monthYear2Thai()` from mixin store
+- Status labels translated: ABSENT→'ขาดราชการ', NORMAL→'ปกติ', LATE→'สาย'
+
+### Environment Variables
+
+Required in `.env.production`:
+- `VITE_API_URI_CONFIG` - Production API base URL
+- `VITE_URL_SSO` - Keycloak SSO logout URL
+- `VITE_URL_USER` - User service URL for redirects
+
+### PWA Configuration
+
+- Auto-update registration with `vite-plugin-pwa`
+- Manifest: "HRMS-Checkin" / "HRMS Checkin"
+- Icons: 192x192 and 512x512 PNG
+- Service worker registered in `src/registerServiceWorker.ts`
+
+## Development Notes
+
+**When adding new features:**
+1. Create API functions in `src/api/`
+2. Define TypeScript interfaces in `src/interface/response/`
+3. Use Pinia stores for complex state, composables for reusable logic
+4. Follow Thai localization patterns for user-facing text
+5. Ensure privacy consent flow for camera/location features
+
+**When working with dates:**
+- Always use `date2Thai()` or `convertDateToAPI()` from mixin store
+- Dates stored in BE format (year + 543)
+- API expects `yyyy-MM-dd` or `yyyy-MM-dd HH:mm:ss` format
+
+**When handling errors:**
+- Use `messageError()` from mixin store for consistent error dialogs
+- 401 errors trigger automatic logout
+- Dialog overlap prevention built into error handling
+
+**When running tests:**
+- Unit tests use Vitest with jsdom environment
+- E2E tests use Cypress with baseUrl: `http://localhost:4173`
+- Test files follow pattern: `*.cy.{js,ts}` or `*.spec.{js,ts}`