---
auto_generated: true
created: 2026-05-18
manual_updated_at: 2026-05-18
modified: 2026-05-18
name: Developer_Manual
status: active
tags:
- client/loreal
- domain/devops
- tech/react
- type/reference
type: reference
---

# Loreal Timelog Viewer Developer Manual

## Architecture Overview
The Loreal Timelog Viewer is a single-page application (SPA) built with React. It follows a client-heavy architecture where the UI is rendered dynamically in the browser. The application is bundled into static JavaScript assets for deployment.

### Component Structure
- **Index Page**: The entry point that loads the main bundle.
- **React Core**: Handles component rendering, state management, and DOM updates.
- **Asset Loading**: Uses dynamic `modulepreload` and `fetch` for efficient resource loading.

## Tech Stack
- **Frontend Framework**: React (Production Build)
- **Language**: JavaScript (ES6+)
- **Build Tool**: Likely Vite, Webpack, or Rollup (based on minified asset naming conventions like `index-BTRMw9pS.js`)
- **State Management**: React Context and `useState`/`useReducer` hooks
- **Routing**: React Router (implicit in SPA structure)

## Local Setup
1. **Prerequisites**: 
   - Node.js (v14 or higher)
   - npm or yarn

2. **Clone the Repository**: 
   ```bash
   git clone <repository-url>
   cd loreal-timelog-viewer
   ```

3. **Install Dependencies**:
   ```bash
   npm install
   ```

4. **Run Development Server**:
   ```bash
   npm start
   ```
   The app will typically run on `http://localhost:3000`.

## Environment Variables
- `REACT_APP_API_URL`: Base URL for the backend API endpoint.
- `REACT_APP_AUTH_PROVIDER`: Specifies the authentication method (e.g., `sso`, `oauth`).
- `REACT_APP_THEME`: Configures the UI theme (e.g., `light`, `dark`).

## Key Services & Entry Points
- **`assets/index-BTRMw9pS.js` / `index-YOc7QQ3i.js`**: These are the compiled production bundles. They contain the React runtime and application logic. 
- **Module Preloading**: The code includes a polyfill/script to handle `modulepreload` for `link[rel="modulepreload"]` elements, optimizing asset loading in the browser.
- **React Runtime**: The code includes the minified React production build, handling elements, components, and hooks.

## API Reference
*Note: The client-side code does not contain API endpoints. The backend API documentation should be consulted for data contracts.*

- **GET /api/timelogs**: Retrieve timelog entries for the authenticated user.
  - **Query Params**: `startDate`, `endDate`, `projectId`
- **POST /api/timelogs**: Create a new timelog entry.
  - **Body**: `{ date, projectId, categoryId, hours, description }`
- **PUT /api/timelogs/{id}**: Update an existing entry.
- **DELETE /api/timelogs/{id}**: Delete an entry (if permissions allow).

## Deployment
1. Build the production assets:
   ```bash
   npm run build
   ```
2. The output files (in `dist/` or `build/`) should be deployed to a static web server (Nginx, Apache, AWS S3, etc.).
3. Ensure CORS headers are correctly configured if the frontend and backend are on different domains.

## Known Gotchas
- **Minified Code**: The source code is minified and mangled (e.g., variables `t`, `e`, `a`). Debugging requires source maps. Ensure source maps are enabled in development but removed in production for security.
- **Module Preload**: The script explicitly handles module preloading. If the server does not support the `rel="modulepreload"` header or resource hints, ensure the fallback logic works correctly.
- **React Version**: The code uses a specific version of React. Ensure compatibility when upgrading dependencies.
- **Global This Polyfill**: The code includes a polyfill for `globalThis`. Ensure it does not conflict with the runtime environment.