# Online Booking Application

## Cliff Hill's Coding Project

This is a full-stack application simulating an online booking system for conference rooms.

---

## Design Decisions

### React Contexts for State Management

- Global state for rooms, bookings, and users via context providers.
- Real-time updates using SSE in context.

### Modular Component Architecture

- Reusable, focused components (e.g., BookingForm, RoomList, RoomSelect, CalendarView).
- Shared UI logic abstracted into dedicated components.

### TypeScript for Safety and Documentation

- Strong typing for all props, state, and data models.
- Centralized type/interface definitions.

### Unified Color and Style Logic

- Room/event colors assigned by room id modulo, using CSS custom properties.
- Consistent visual theming across lists, dropdowns, and calendar.

### Separation of Concerns

- Business logic and API calls abstracted into helpers and service modules.
- Thin UI components focused on rendering and interaction.

### Robust Error Handling and Validation

- Field-level validation and user-friendly error messages in forms.
- Backend errors formatted for clarity.

### Centralized Logging

- Logging utility used throughout frontend and backend for analytics and debugging.
- Key actions and lifecycle events are logged.

### JSDoc and Docstrings for Documentation

- File-level and component-level documentation in both frontend and backend.
- TypeScript interfaces and Python models are documented.

### React Router for Navigation

- Page routing and programmatic navigation after booking actions.

### Accessibility and User Experience

- Disabled states, error messages, and skeleton loaders for better UX.
- Visual distinction for selected/unavailable rooms.

### FastAPI Backend with SQLAlchemy ORM

- Async API endpoints grouped by resource (rooms, bookings, users).
- Database models with relationships and constraints.

### Pydantic Schemas for Validation

- Separate schemas for create, update, and response objects.

### Service Layer Abstraction in Backend

- Business logic separated from HTTP routing.

### Testing and Code Quality

- Pytest, coverage, pre-commit hooks, and code style enforcement for backend; run `pytest` from the backend folder.
- Jest and React Testing Library, code style enforcement and additional pre-commit hooks for frontend; run `yarn run jest` from the frontend folder.
- All tests can be run from the`nox` command in the root directory, or for tests specific to each part of the project, run `nox` in either `frontend` or `backend` respectively.
  - `nox` frontend tests include: `pre-commit`, `coverage`, `audit`, `storybook`, and `jest`.
  - `nox` backend tests include: `pre-commit`, `safety`, `mypy`, `tests`, `typeguard`, `xdoctest`, and `docs-build`.

`nox` could very easily be integrated into a CICD pipeline for full validation of the code to be done before anything could be merged into `main`.

### Docker Compose for Orchestration

- Multi-service setup: backend (FastAPI), frontend (React), and Postgres database.
- Custom network, healthchecks, and persistent volumes.
- Environment variables managed via .env files.

### Extensibility and Maintainability

- Modular design for easy feature addition and refactoring.
- Generated from Hypermodern Python Cookiecutter for best practices.

### AI Use

I used AI to stub out a couple of files:

- I use primarily copilot inside my VSCode. This was done through conversations I had with the AI about the state of the code, and ways to improve things, or for setting up documentation, etc as I explain below.
- Any use is extremely caveated by me needing to adjust and correct what was conceieved by the AI, as it is a helpful tool, but often gets little details incorrect.
- The Dockerfile.backend and Dockerfile.frontend - to speed up the process of getting docker loaded efficiently for the project.
- The compose.yml file - getting the different images gathered together quickly.
- The compose.dev.yml file - used to get a further understanding of how to hook up an extension to the previous file.
- The mermaid diagrams used in this file.
- I have the CodeGPT plugin in VSCode, and it has helped with docstrings, logging messages, and sometimes reducing the time it takes me to write out the code.
- I used AI to rapidly set up tests for each users component (router, service), then adapted it to the others independently. I believe AI is great for getting reasonable tests written quickly, and then I simply refined it, and replicated the kinds of tests across the different components.
- I was experimenting with some AI edits for debugging the tests.
- My frontend skills are less polished than my backend skills. I've been using AI along the lines of how I would use StackOverflow, answering questions to help me get the code written.
  - AI was very helpful in getting the frontend to do what I wanted quickly.
- I used AI to help clean up and better structure the CSS for the frontend project, as well as get some code documentation in place.
- AI was used to refactor code a few times to make it cleaner and better organized.
- AI was used for debugging the tests to quickly correct them, for frontend and backend.

---

## Documentation & Storybook

### Backend API Documentation

To build and view the backend API documentation:

1. Navigate to the backend directory:

```bash
cd backend
```

2. Run the Nox docs session (live-reloading server):

```bash
nox -s docs
```

This will build and serve the docs with live reloading. Your browser should open automatically to the docs at:
[http://localhost:8000/docs](http://localhost:8000/docs)

**Alternative (static build):**

If you want to build the static HTML docs only:

```bash
cd backend
nox -s docs-build
xdg-open docs/_build/index.html  # Linux
open docs/_build/index.html      # macOS
start docs/_build/index.html     # Windows
```

Or manually open `docs/_build/index.html` in your browser.

### Frontend Storybook

To run Storybook for the frontend using Nox:

1. Navigate to the frontend directory:

```bash
cd frontend
```

2. Run the Nox storybook session:

```bash
nox -s storybook
```

This will start Storybook and open your browser to:
[http://localhost:6006](http://localhost:6006)

**Alternative (static build):**

If you want to build the static Storybook docs only:

```bash
cd frontend
nox -s storybook-build
xdg-open storybook-static/index.html  # Linux
open storybook-static/index.html      # macOS
start storybook-static/index.html     # Windows
```

Or manually open `storybook-static/index.html` in your browser.

---

## Development Environment Setup

Follow these steps to get your local development environment running:

### 1. Clone the repository

You can use either HTTPS or SSH:

**HTTPS:**

```bash
git clone https://github.com/xlorepdarkhelm/numinar-coding-project.git
cd numinar-coding-project
```

**SSH:**

```bash
git clone git@github.com:xlorepdarkhelm/numinar-coding-project.git
cd numinar-coding-project
```

### 2. Copy environment variables

```bash
cp .env.example .env
# Or, if present:
cp .env.sample .env
```

### 3. Install backend dependencies

```bash
cd backend
poetry install
```

### 4. Set up pre-commit hooks (recommended)

```bash
pre-commit install
```

### 5. Install frontend dependencies

```bash
cd ../frontend
yarn install
```

### 6. Start Docker Compose in development mode (in a separate terminal)

From the project root:

```bash
docker compose -f compose.dev.yml up
```

This will start the backend (port 8000), frontend (port 3000), and Postgres (port 5432) with hot-reload enabled for rapid development.

### 7. Run tests (backend & frontend)

#### Backend tests

```bash
cd backend
nox           # Run all tests and checks (also builds API docs)
# or run only unit tests:
nox --session=tests
```

##### API Documentation

- The `nox` command above will also build the backend API documentation.
- **View the API docs in development mode:** Open [http://localhost:8000/docs](http://localhost:8000/docs) in
  your browser (when running dev Docker Compose).
- **Generated static docs (after running nox):** See `backend/docs/build/index.html` relative to the project
  root.

#### Frontend tests

```bash
cd frontend
nox
# or run only nox tests:
nox --session=jest
```

#### All tests

from the project root

```bash
nox
```

Note - you can use any of the sessions from frontend or backend here to isolate just that test.

## Nox and Pre-commit Integration

This project uses [Nox](https://nox.thea.codes/) for orchestrating development, testing, and code quality sessions across both frontend and backend. Pre-commit hooks are managed via [pre-commit](https://pre-commit.com/) and are integrated into the Nox workflow for consistent linting and formatting.

- **Nox sessions** are defined in both the project root and in the `frontend` and `backend` directories. You can run all sessions from the root, or target frontend/backend specifically.
- **Pre-commit** is run as a Nox session (`nox -s pre-commit`) and also as a git hook. Both use pinned tool versions and shared config files for consistency.
- **Typical usage:**
  - Run all checks: `nox` (from root)
  - Run only frontend checks: `cd frontend && nox`
  - Run only backend checks: `cd backend && nox`
  - Run pre-commit manually: `nox -s pre-commit` or `pre-commit run --all-files`

## Troubleshooting & FAQ

**Q: Why does isort or black change files differently in Nox vs pre-commit?**
A: Make sure both Nox and pre-commit are using the same pinned tool versions and config files. See `.isort.cfg` and `.pre-commit-config.yaml` for details.

**Q: Why does Storybook open the browser or not exit when run in CI/Nox?**
A: Use `yarn build-storybook` for static builds (exits automatically). For dev server, use `yarn storybook dev --ci` to prevent browser opening.

**Q: Why do pre-commit hooks modify files after a commit or behave differently in CI?**
A: Pre-commit runs in its own environment. Always run `pre-commit run --all-files` locally to reproduce CI behavior. Ensure your config files are up to date and tool versions are pinned.

**Q: How do I run only frontend or backend tests?**
A: Use Nox in the respective directory (`cd frontend && nox`, `cd backend && nox`).

**Q: How do I fix environment or dependency issues?**
A: Delete `.venv` or `node_modules` and reinstall dependencies (`poetry install` for backend, `yarn install` for frontend). Check for version mismatches in config files.

**Q: Where are config files for formatting and type checking?**
A: See `.isort.cfg`, `.coveragerc`, and `mypy.ini` in the project root. These are derived from backend settings for consistency.

---

## Diagrams

### Docker Compose Components

```mermaid
%% Docker Compose Architecture
graph TD
  subgraph docker_network
    B[Frontend<br/>Port: 3000]
    C[Backend<br/>Port: 8000]
    D[PostgreSQL<br/>Port: 5432]
    C -- "SQL: 5432" --> D
  end
  Client[Client] -- "HTTP: 3000" --> B
  Client -- "HTTP/REST: 8000" --> C
```

---

### Database Schema Diagram

```mermaid
%% Database Schema with Types and Keys
classDiagram
  class User {
    string email [PK]
    string name
  }
  class Room {
    int id [PK]
    string name
    string location
    string equipment
    int capacity
  }
  class Booking {
    int id [PK]
    int room_id [FK]
    datetime start_time
    datetime end_time
    string title
  }
  class Invitee {
    int id [PK]
    int booking_id [FK]
    string user_email [FK]
  }

  User "1" <|-- "*" Invitee : user_email [FK]
  Room "1" <|-- "*" Booking : room_id [FK]
  Booking "1" <|-- "*" Invitee : booking_id [FK]
```

---

### Component Diagram

```mermaid
%% Component Relationships and Data Flow
graph TD
    subgraph Frontend
        F1[Pages] --> F2[Components]
        F2 --> F3[API Calls]
    end
    subgraph Backend
        B1[FastAPI Routers] --> B2[Pydantic Schemas]
        B1 --> B3[Service Layer]
        B3 --> B4[SQLAlchemy Models]
        B4 --> B5[PostgreSQL]
    end
    F3 -- REST --> B1
    B5 -.->|External| PG[PostgreSQL Service]
```

---

### Backend Request Data Path

```mermaid
%% Backend Request Data Path with Error Handling
sequenceDiagram
  participant Frontend
  participant FastAPI_Router as FastAPI Router
  participant API_Endpoint as API Endpoint
  participant Pydantic_Schema as Pydantic Schema
  participant Service_Layer as Service Layer
  participant DB_Model as DB Model
  participant Database

  Frontend->>FastAPI_Router: HTTP Request (REST)
  FastAPI_Router->>API_Endpoint: Route Match
  API_Endpoint->>Pydantic_Schema: Validate & Parse Input
  alt Validation Error
    Pydantic_Schema-->>Frontend: HTTP 422 Unprocessable Entity
  else Validated
    Pydantic_Schema-->>API_Endpoint: Validated Data
    API_Endpoint->>Service_Layer: Pass Data
    Service_Layer->>DB_Model: Business Logic
    DB_Model->>Database: DB Query/Update
    Database-->>DB_Model: Query Result
    DB_Model-->>Service_Layer: Data
    Service_Layer-->>API_Endpoint: Response Data
    API_Endpoint-->>Frontend: HTTP Response (JSON)
  end
```

---

### SSE Update Flow

```mermaid
%% SSE Update Flow with Event Types
sequenceDiagram
  participant Frontend
  participant FastAPI_Router as FastAPI Router
  participant SSE_Endpoint as SSE Endpoint
  participant Event_Generator as Event Generator
  participant Publisher as Publisher

  Frontend->>SSE_Endpoint: Open EventSource /availability/stream
  SSE_Endpoint->>Event_Generator: Start Async Event Loop
  loop While Connected
    Event_Generator->>Publisher: Wait for Event or Timeout
    Publisher-->>Event_Generator: Room Availability Event | Keep-Alive
    Event_Generator-->>Frontend: Send SSE Event (data: {type: "availability" | "keep-alive"})
    note over Publisher,Frontend: Trigger: Booking created/updated/deleted
  end
  Frontend-->>SSE_Endpoint: Disconnect (close EventSource)
  SSE_Endpoint-->>Event_Generator: Cleanup Subscriber
```

---