BookMyShow — Low-Level Design

A TypeScript implementation of the BookMyShow online movie ticket booking system, built as a Low-Level Design (LLD) exercise. Focuses on OOP principles, design patterns, and clean class modeling.

Design

Core Classes

Class	Responsibility
BookMyShow	App entry point — manages theatres, movie-to-show index, and ticket booking
Theatre	Holds shows and seat capacity, tied to a Location
Movie	Movie entity with language, genre, and rating
Show	A specific screening — links a Movie to a Theatre at a given time, tracks available seats
Ticket	Booking record — owner, show, seat count, payment method, cancellation state
RegisteredUser	Authenticated user with booking history
GuestUser	Unauthenticated user

Interfaces & Patterns

• IUser — shared interface for registered and guest users
• IPaymentMethod — payment abstraction (card, cash, etc.)
• IPaymentMethodFactory — Factory pattern for creating payment method instances at booking time

Enums

• Genre — action, thriller, romance, etc.
• Language — English, Bangla, etc.
• PaymentMethods — available payment types

Features

• Search shows by movie name across all theatres
• Book tickets with seat count validation and real-time seat availability tracking
• Multiple payment methods via the Factory pattern
• Ticket cancellation
• Per-user booking history
• Registered user and guest user flows

Prerequisites

• Node.js
• TypeScript / ts-node

Setup

git clone https://github.com/adnansabbir/bookMyShow.git
cd bookMyShow
npm install

Run

npm start

Runs the demo in src/index.ts — sets up theatres, movies, shows, and users, then books and cancels tickets, printing the booking history to the console.

Project Structure

src/
├── classes/
│   ├── BookMyShow.ts
│   ├── Theatre.ts
│   ├── Location.ts
│   ├── Movie.ts
│   ├── Show.ts
│   ├── Ticket.ts
│   ├── RegisteredUser.ts
│   ├── GuestUser.ts
│   ├── IUser.ts
│   ├── IPaymentMethod.ts
│   └── IPaymentMethodFactory.ts
├── enums/
│   ├── Genre.enum.ts
│   ├── Language.enum.ts
│   └── PaymentMethods.enum.ts
└── index.ts

License

MIT