# GoodGo Platform Frontend Exploration Report
## apps/web (Next.js 15 with App Router)

**Date:** April 9, 2026  
**Status:** Pre-i18n (No existing i18n setup detected)  
**Next.js Version:** 15.5.14 | **React:** 18.3.0  
**Primary Language:** Vietnamese (vi_VN)

---

## 📁 Directory Structure Overview

```
apps/web/
├── app/                          # Next.js App Router (main application)
│   ├── layout.tsx               # Root layout with metadata & providers
│   ├── globals.css              # Global Tailwind styles & theme variables
│   ├── middleware.ts            # Already exists (auth routing middleware)
│   ├── loading.tsx              # Root loading state
│   ├── error.tsx                # Root error boundary
│   ├── not-found.tsx            # 404 page
│   │
│   ├── (public)/                # Public route group
│   │   ├── layout.tsx           # Public layout with header/footer
│   │   ├── page.tsx             # Landing page (hero + featured listings)
│   │   ├── search/              # Search results page
│   │   │   ├── page.tsx
│   │   │   ├── layout.tsx
│   │   │   ├── error.tsx
│   │   │   ├── loading.tsx
│   │   │   └── __tests__/
│   │   └── listings/[id]/       # Listing detail page
│   │       └── page.tsx
│   │
│   ├── (auth)/                  # Auth route group
│   │   ├── layout.tsx
│   │   ├── login/page.tsx       # Login form
│   │   ├── register/page.tsx    # Registration form
│   │   ├── error.tsx
│   │   ├── loading.tsx
│   │   └── __tests__/
│   │
│   ├── (dashboard)/             # Protected dashboard route group
│   │   ├── layout.tsx           # Dashboard layout with sidebar nav
│   │   ├── dashboard/page.tsx   # Main dashboard
│   │   ├── listings/
│   │   │   ├── page.tsx         # User listings list
│   │   │   ├── new/page.tsx     # Create listing (multi-step form)
│   │   │   └── [id]/edit/page.tsx
│   │   ├── analytics/page.tsx
│   │   ├── profile/page.tsx     # User profile settings
│   │   ├── subscription/page.tsx # Subscription plans
│   │   ├── payments/page.tsx    # Payment history
│   │   ├── valuation/page.tsx   # AI property valuation
│   │   ├── error.tsx
│   │   ├── loading.tsx
│   │   └── __tests__/
│   │
│   ├── (admin)/                 # Admin route group
│   │   ├── layout.tsx
│   │   ├── admin/page.tsx       # Admin dashboard
│   │   ├── admin/users/page.tsx
│   │   ├── admin/kyc/page.tsx
│   │   ├── admin/moderation/page.tsx
│   │   ├── error.tsx
│   │   └── loading.tsx
│   │
│   ├── auth/                    # Auth callbacks
│   │   └── callback/
│   │       ├── google/page.tsx
│   │       └── zalo/page.tsx
│   │
│   ├── api/                     # API routes
│   │   └── health/route.ts
│   │
│   ├── robots.ts
│   └── sitemap.ts
│
├── components/                   # Reusable React components
│   ├── providers/               # Context providers
│   │   ├── auth-provider.tsx    # Auth context & store wrapper
│   │   ├── query-provider.tsx   # TanStack React Query provider
│   │   └── theme-provider.tsx   # Dark/light mode provider
│   │
│   ├── ui/                      # Unstyled base UI components
│   │   ├── button.tsx           # CVA-based button variants
│   │   ├── input.tsx
│   │   ├── label.tsx
│   │   ├── card.tsx
│   │   ├── dialog.tsx           # Modal dialog
│   │   ├── tabs.tsx
│   │   ├── select.tsx           # Custom select component
│   │   ├── badge.tsx
│   │   ├── textarea.tsx
│   │   ├── table.tsx
│   │   └── __tests__/           # Component tests
│   │
│   ├── auth/
│   │   └── oauth-buttons.tsx    # Google & Zalo OAuth buttons
│   │
│   ├── search/
│   │   ├── filter-bar.tsx       # Search filters (transaction, property, price range)
│   │   ├── property-card.tsx    # Property listing card
│   │   └── search-results.tsx   # Results container
│   │
│   ├── listings/
│   │   ├── listing-form-steps.tsx      # Multi-step create/edit form
│   │   ├── image-upload.tsx            # Image upload component
│   │   ├── image-gallery.tsx           # Image gallery viewer
│   │   └── listing-status-badge.tsx    # Status display badge
│   │
│   ├── map/
│   │   └── listing-map.tsx      # Mapbox GL integration
│   │
│   ├── valuation/
│   │   ├── valuation-form.tsx
│   │   ├── valuation-results.tsx
│   │   ├── valuation-history.tsx
│   │   └── ai-estimate-button.tsx
│   │
│   └── charts/
│       ├── price-trend-chart.tsx
│       ├── agent-performance.tsx
│       └── district-heatmap.tsx
│
├── lib/                         # Utilities and hooks
│   ├── utils.ts                # cn() - clsx + tailwind-merge
│   ├── auth-store.ts           # Zustand auth state management
│   ├── api-client.ts           # Axios/fetch wrapper
│   ├── query-client.ts         # TanStack React Query config
│   │
│   ├── hooks/
│   │   ├── use-listings.ts
│   │   ├── use-analytics.ts
│   │   ├── use-valuation.ts
│   │   ├── use-payments.ts
│   │   └── use-subscription.ts
│   │
│   ├── validations/            # Zod schemas
│   │   ├── auth.ts            # Login/register schemas
│   │   ├── listings.ts        # Multi-step listing schemas
│   │   └── valuation.ts
│   │
│   ├── *-api.ts               # API clients
│   │   ├── auth-api.ts
│   │   ├── listings-api.ts
│   │   ├── profile-api.ts
│   │   ├── payment-api.ts
│   │   ├── subscription-api.ts
│   │   ├── analytics-api.ts
│   │   ├── valuation-api.ts
│   │   └── admin-api.ts
│   │
│   └── __tests__/            # Unit tests (Vitest + React Testing Library)
│       ├── auth-store.spec.ts
│       ├── auth-validations.spec.ts
│       ├── listing-validations.spec.ts
│       └── utils.spec.ts
│
├── public/                     # Static assets
│   └── [images, icons, etc.]
│
├── .next/                      # Build output (generated)
├── node_modules/
│
└── Configuration Files:
    ├── package.json            # Dependencies & scripts
    ├── next.config.js          # Next.js config (Sentry, CSP, headers)
    ├── tailwind.config.ts      # Tailwind CSS config
    ├── postcss.config.js       # PostCSS config (Tailwind + Autoprefixer)
    ├── tsconfig.json           # TypeScript config (extends base)
    ├── vitest.config.ts        # Testing framework config
    ├── vitest.setup.ts         # Test setup
    ├── middleware.ts           # Auth routing middleware
    ├── sentry.*.config.ts      # Sentry error tracking (3 files)
    ├── instrumentation.ts      # Server instrumentation
    └── global.d.ts             # Global TypeScript definitions
```

---

## 📦 Package.json Dependencies

### Production Dependencies:
```json
{
  "@hookform/resolvers": "^5.2.2",      // Form validation resolver
  "@sentry/nextjs": "^10.47.0",         // Error tracking
  "@tanstack/react-query": "^5.96.2",   // Data fetching & caching
  "class-variance-authority": "^0.7.1", // Component variant utilities
  "clsx": "^2.1.1",                     // Class name utility
  "lucide-react": "^1.7.0",             // Icon library
  "mapbox-gl": "^3.21.0",               // Map library
  "next": "^14.2.0",                    // Framework
  "react": "^18.3.0",
  "react-dom": "^18.3.0",
  "react-hook-form": "^7.72.1",         // Form state management
  "recharts": "^3.8.1",                 // Chart library
  "tailwind-merge": "^3.5.0",           // Merge Tailwind conflicts
  "zod": "^4.3.6",                      // Schema validation
  "zustand": "^5.0.12"                  // Lightweight state management
}
```

### Dev Dependencies (including testing):
```json
{
  "@testing-library/jest-dom": "^6.9.1",
  "@testing-library/react": "^16.3.2",
  "@testing-library/user-event": "^14.6.1",
  "@vitejs/plugin-react": "^4.7.0",
  "vitest": "^4.1.3",
  "tailwindcss": "^3.4.0",
  "tailwindcss-animate": "^1.0.7",
  "msw": "^2.13.2",                     // Mock Service Worker
  "typescript": "^6.0.2"
}
```

---

## 🎯 Root Layout (app/layout.tsx)

### Current Implementation:
- **HTML language:** `lang="vi"` (Vietnamese hardcoded)
- **Metadata structure:** Vietnamese title & description
- **OpenGraph:** Locale set to `vi_VN`
- **Providers stacked:** `ThemeProvider → QueryProvider → AuthProvider`
- **Accessibility:** Includes skip-to-main-content link (already A11y compliant)
- **Theme color:** `#15803d` (primary green)

### Current Metadata:
```javascript
title: 'GoodGo — Nền tảng Bất động sản Việt Nam'
description: 'GoodGo — nền tảng bất động sản thông minh tại Việt Nam...'
openGraph: { locale: 'vi_VN', ... }
```

---

## 🔐 Middleware (middleware.ts)

### Current Auth Routing:
```typescript
- Public paths: /login, /register, /search, /auth/callback, / (root)
- Protected paths: Anything else requires 'goodgo_authenticated' cookie
- Auth-only paths: /login, /register (redirects to /dashboard if authenticated)
- Redirect param: Adds ?redirect=[original-path] on unauthorized access
```

**Key Entry Points to Update for i18n:**
- Locale prefix detection needed (e.g., `/en/dashboard`, `/vi/dashboard`)
- Cookie/header locale detection

---

## 🎨 Tailwind Configuration

### Theme Setup (tailwind.config.ts):
```typescript
- Dark mode: 'class' based
- Content paths: ./app/**, ./components/**, ./lib/**
- Colors: HSL-based CSS variables (--primary, --secondary, etc.)
- Border radius: Customizable via --radius CSS variable
- Animation plugin: tailwindcss-animate
```

### Global Styles (app/globals.css):
- **CSS Variables:** Light mode + dark mode color schemes
- **Primary color:** HSL(142.1, 76.2%, 36.3%) — green
- **All components:** Use @apply border-border for consistency
- **Root background:** HSL variables applied

---

## 🗣️ Text Content & i18n Points

### Hardcoded Vietnamese Text Locations:

#### Layout & Navigation:
- `app/(public)/layout.tsx` — Header nav: "Trang chủ", "Tìm kiếm", "Đăng nhập", "Đăng ký"
- `app/(dashboard)/layout.tsx` — Dashboard nav items (8 items + theme toggle label)
- Footer in public layout — Section headings, links

#### Pages:
- `app/(public)/page.tsx` — Landing page (hero, search bar, districts, stats, CTA)
- `app/(auth)/login/page.tsx` — Form labels, error messages (OAUTH_ERROR_MESSAGES object)
- `app/(auth)/register/page.tsx` — Similar form structure

#### Components:
- `components/search/filter-bar.tsx` — Filter labels (PRICE_RANGES), city names
- `components/search/property-card.tsx` — Property info badges, direction labels
- `components/listings/listing-form-steps.tsx` — Form labels, validation messages
- `components/ui/label.tsx` — Form labels across app

#### API Error Messages & Zod Validation:
- `lib/validations/listings.ts` — Zod error messages (Vietnamese)
- `lib/validations/auth.ts` — Auth validation messages
- `components/auth/oauth-buttons.tsx` — Button text ("Google", "Zalo")

---

## 🧩 Key Components Requiring Translation

### Forms (Form validation + labels):
1. **Login Form** (`app/(auth)/login/page.tsx`)
   - Phone input label, password label, errors
   - OAuth button labels
   - Link text: "Chưa có tài khoản? Đăng ký"

2. **Register Form** (`app/(auth)/register/page.tsx`)
   - Similar structure to login

3. **Listing Creation** (`components/listings/listing-form-steps.tsx`)
   - Multi-step form with labels for:
     - Transaction type (Bán/Cho thuê)
     - Property type (Căn hộ/Nhà riêng/etc)
     - Location (address, ward, district, city)
     - Details (area, bedrooms, bathrooms, direction)
     - Pricing

4. **Search Filter** (`components/search/filter-bar.tsx`)
   - Transaction/Property/Price/Area selects
   - City options (13 Vietnamese cities)

### UI Components:
- **Buttons:** Text labels ("Đăng nhập", "Tìm kiếm", "Gửi", etc.)
- **Badge:** Labels for property types, statuses, directions
- **Input labels:** Across all forms
- **Error messages:** Alert text

### Navigation:
- **Public header:** 4 main nav items + user menu
- **Dashboard nav:** 8 main sections + theme toggle
- **Footer:** 4 columns of links + copyright

---

## ♿ Accessibility (Current State - WCAG 2.1 AA)

### Already Implemented ✅:
- Skip-to-main-content link (hidden, appears on focus)
- Semantic HTML: `<header>`, `<nav>`, `<main>`, `<footer>`
- `aria-label` on navigation items
- `aria-label` on property cards (for screen readers)
- `role="alert"` on error messages
- `aria-invalid` on form inputs
- Form labels linked with `htmlFor`
- Image alt text on property images
- `aria-hidden="true"` on decorative elements

### Accessibility Gaps to Fix 🔧:
1. **Color contrast:** Need to verify against WCAG AA standards
2. **Focus indicators:** Ensure visible focus states on all interactive elements
3. **Dialog/Modal:** Need proper focus management in dialogs
4. **Forms:** Ensure field grouping with `<fieldset>` where applicable
5. **Error handling:** Some error messages lack clear labels
6. **Loading states:** Spinner needs `aria-busy` or `aria-label`
7. **Tables:** Data tables need proper headers (`<th>`, `scope`)
8. **Links:** "Xem tất cả" links should have context or aria-labels
9. **Icon-only buttons:** Need proper `aria-label`
10. **Text alternatives:** Ensure all meaningful icons have descriptive labels

### ARIA Implementation Points:
- Dropdown navigation (if complex)
- Tab interfaces (recharts/charts)
- File upload components
- Date/time inputs (if added)

---

## 🔗 Current Locale Setup

### Status: **NO EXISTING i18n**
- No `next-intl` package
- No translation files (JSON/YAML)
- No locale routes (`/en/*`, `/vi/*`)
- No i18n middleware
- **Language is hardcoded to Vietnamese everywhere**

### Where i18n Will Be Integrated:
1. **Middleware:** Detect locale from URL, cookie, or `Accept-Language` header
2. **Layout wrapper:** `[locale]/layout.tsx` folder structure
3. **Message providers:** `next-intl` Provider in root layout
4. **API responses:** May need to internationalize error messages from backend

---

## 🔒 Security Configuration

### Next.js Config Security Headers:
- `X-Content-Type-Options: nosniff`
- `X-Frame-Options: DENY`
- `X-XSS-Protection: 1; mode=block`
- `Content-Security-Policy` with Mapbox domains whitelisted
- `Permissions-Policy` restricting camera/microphone/geolocation

### Auth Middleware:
- Cookie-based auth check (`goodgo_authenticated`)
- Protected routes redirect to `/login?redirect=...`
- Public route protection in middleware

---

## 📊 Key Data Structures & Enums

### Transaction Types:
```typescript
const TRANSACTION_TYPES = [
  { value: 'SALE', label: 'Bán' },
  { value: 'RENT', label: 'Cho thuê' },
];
```

### Property Types:
```typescript
const PROPERTY_TYPES = [
  { value: 'APARTMENT', label: 'Căn hộ' },
  { value: 'HOUSE', label: 'Nhà riêng' },
  { value: 'VILLA', label: 'Biệt thự' },
  { value: 'LAND', label: 'Đất nền' },
  { value: 'OFFICE', label: 'Văn phòng' },
  { value: 'SHOPHOUSE', label: 'Shophouse' },
];
```

### Listing Statuses:
```typescript
const LISTING_STATUSES = {
  DRAFT, PENDING_REVIEW, ACTIVE, RESERVED, SOLD, RENTED, EXPIRED, REJECTED
};
```

### Directions:
```typescript
const DIRECTIONS = [
  { value: 'NORTH', label: 'Bắc' },
  { value: 'SOUTH', label: 'Nam' },
  { value: 'EAST', label: 'Đông' },
  { value: 'WEST', label: 'Tây' },
  // ... and diagonal combinations
];
```

### Cities (13 total):
```typescript
Hồ Chí Minh, Hà Nội, Đà Nẵng, Nha Trang, Cần Thơ, Hải Phòng,
Bình Dương, Đồng Nai, Long An, Bà Rịa - Vũng Tàu, [+ more]
```

---

## 🧪 Testing Setup

### Test Framework: Vitest + React Testing Library
- **Config file:** `vitest.config.ts`
- **Setup file:** `vitest.setup.ts`
- **Test files:** Located alongside source (`__tests__` folders)

### Current Test Coverage:
- Component tests for UI library
- Auth store tests
- Validation schema tests
- Utility function tests

### Testing Best Practices for i18n:
- Mock i18n provider in test setup
- Test both locale variants
- Verify translations render correctly

---

## 🚀 Implementation Readiness

### Ready for i18n Implementation:
✅ Centralized validation messages (Zod schemas)  
✅ Enum/constant-based UI text (TRANSACTION_TYPES, PROPERTY_TYPES, etc.)  
✅ Component library with consistent patterns  
✅ TypeScript for type safety  
✅ Middleware support for locale routing  

### Minor Refactoring Needed:
⚠️ Extract some hardcoded strings from components  
⚠️ Move form error messages to message files  
⚠️ Centralize page metadata for i18n  

---

## 📝 Summary: i18n & A11y Implementation Points

| Area | Current State | Needs Work |
|------|---------------|-----------|
| **Locale Support** | Hardcoded to Vietnamese | Implement next-intl with routing |
| **Translation Keys** | Scattered throughout code | Centralize in message files |
| **Validation Messages** | In Zod schemas (Vietnamese) | Extract to i18n messages |
| **Component Text** | Hardcoded strings | Use i18n hook |
| **Metadata/SEO** | Hardcoded Vietnamese | Generate for each locale |
| **Color Contrast** | Likely AA compliant | Audit and verify |
| **Focus Management** | Partial (buttons/links ok) | Add to modals & dropdowns |
| **ARIA Labels** | Good coverage | Complete missing labels |
| **Error Messages** | Most have aria-invalid | Add more context to some |
| **Loading States** | Spinner exists | Add aria-busy, better labels |
| **Tables** | Basic structure | Add proper header semantics |

---

## 🗂️ File Count Summary

- **App routes:** ~15 page files
- **Components:** ~35 component files
- **Lib utilities:** ~20 files (hooks, APIs, validations)
- **Tests:** ~15 test files
- **Config files:** ~8 configuration files
- **Total TypeScript/TSX files:** ~90+

---

## Next Steps for Implementation

1. **Install i18n:** Add `next-intl` to dependencies
2. **Create message files:** Set up `messages/en.json` and `messages/vi.json`
3. **Refactor middleware:** Add locale detection & routing
4. **Update root layout:** Wrap with i18n provider
5. **Update all components:** Replace hardcoded strings with `useTranslations()`
6. **Test both locales:** Ensure all pages render correctly
7. **A11y audit:** Use axe DevTools to identify remaining issues
8. **Focus management:** Add focus trapping in modals
9. **Testing:** Update test setup for i18n mocking

---

**Report Generated:** April 9, 2026  
**Exploration Scope:** Thorough  
**Confidence:** High