Taxi Fare Calculator

A TypeScript-based taxi fare calculator that allows for flexible fare calculation algorithms, detailed logging, and easy integration with different input methods.

Table of Contents

• Features
• Installation
• Running in Dev Mode
• Running in Production Mode
• Running Tests
• Usage
• Logs
• Test Case

Features

• Separation of Concerns: Core logic is decoupled from auxiliary services like logging.
• Modular Components: Each component handles a specific responsibility, making the code maintainable and extensible.
• Flexible Fare Calculation: You can set custom fare calculation algorithms without modifying the core class.
• Optional Logger: The system functions normally even if no logger is provided.
• Detailed Error Handling: Specific error messages and logging make debugging easier.
• Data Validation and Parsing: Ensures input data is correctly formatted and logically coherent.
• Type Safety: Uses TypeScript for compile-time type safety.
• Record Management: Handles the addition, validation, and sorting of records efficiently.

Installation

1. Clone the repository:

   git clone https://github.com/mirzaakhena/taxi-fare-calculator.git
   cd taxi-fare-calculator

2. Install dependencies:

   npm install

Running in dev mode

npm run dev

Running in production mode

First you need to build it

npm run build

Then you can run it directly from /dist directory

npm run start

Running test

npm test

Usage

1. Manual Direct Input. See sample_input_manual.ts
2. Manual Direct Input with Custom Algorithm sample_input_change_fare_algorithm.ts
3. Receive Input Line by Line sample_input_line_by_line.ts

You may enable it by comment / uncomment it in index.ts then run it in dev mode.

import { receiveInputLineByLine } from "./sample_input_line_by_line.js";
import { manualDirectInput } from "./sample_input_manual.js";
import { manualDirectInputWithChangingAlgorithm } from "./sample_input_change_fare_algorithm.js";

receiveInputLineByLine();
// manualDirectInput();
// manualDirectInputWithChangingAlgorithm();

Logs

When using the sample from receiveInputLineByLine, it uses winston library that store all the log in logs/app.log.

Test Case

Adding Records:

• Valid Records: Test that valid records are added without errors.

• Invalid Format: Test that an error is thrown for invalid record format.

• Blank Line: Test that an error is thrown for a blank line.

• Past Time: Test that an error is thrown when a record with past time is added.

• Interval More Than 5 Minutes: Test that an error is thrown when the interval between records exceeds 5 minutes.

• Smaller Distance: Test that an error is thrown when a new record has a smaller distance than the previous record.

Fare Calculation:

• Fewer Than 2 Records: Test that an error is thrown if there are fewer than two records.

• One Record: Test that an error is thrown if there is only one record.

• No Movement: Test that an error is thrown if there is no movement (total mileage is 0.0 m).

• Edge Case (Up to 1 km): Test that the fare is correctly calculated for distances just over 1 km.

• Up to 1 km: Test that the fare is 400 yen for distances up to 1 km.

• Up to 10 km: Test that the fare is correctly calculated for distances up to 10 km.

• Over 10 km: Test that the fare is correctly calculated for distances over 10 km.

• Changing Fare Algorithm: Test that the fare calculation algorithm can be changed and applied correctly.

Sorted Records:

• Sorted by Distance Difference: Test that records are correctly sorted by distance difference.

Base Fare:

• Up to 1 km: Test that the base fare is 400 yen for distances up to 1 km.

• 1 km to 10 km: Test that the fare is correctly calculated for distances between 1 km and 10 km.

• Over 10 km: Test that the fare is correctly calculated for distances over 10 km.