Task Manager - OOP & File Management

A comprehensive command-line task management application built with Object-Oriented Programming principles and persistent file storage.

Team Members

• Belinda Belange Larose
• Grace Munezero
• Kevine Umutoni
• Plamedi Mayala

Video Walkthrough

🎥 Watch the complete application demo: Task Manager Walkthrough

This video demonstrates all features and functionality of the Task Manager application.

Table of Contents

• Project Overview
• Features
• Prerequisites
• Installation
• Usage
• Project Structure
• Object-Oriented Design
• Data Storage
• Testing
• Contributing
• License

Project Overview

This Task Manager application demonstrates advanced Object-Oriented Programming concepts while providing a practical solution for personal productivity and task organization. Users can create, manage, and track tasks through an intuitive command-line interface with persistent data storage.

Features

Core Functionality

• ✅ CRUD Operations: Create, Read, Update, Delete tasks
• 📋 Task Properties: Title, description, priority, due date, category, completion status
• 🎯 Task Types: Regular tasks, Work tasks, Personal tasks
• 💾 Data Persistence: JSON file-based storage with automatic backup
• 🔍 Search & Filter: Find tasks by keywords, category, priority, or status
• 📊 Sorting: Sort by creation date, due date, priority, or title
• 📈 Statistics: Track completion rates and task analytics

Advanced Features

• ⚠️ Overdue Detection: Automatic identification of overdue tasks
• 📅 Due Date Tracking: Monitor tasks approaching their due dates
• 🏷️ Categorization: Organize tasks by custom categories
• 📤 Export/Import: Backup and restore task data
• 🔒 Data Validation: Comprehensive input validation and error handling
• 🔄 Auto-backup: Automatic backup system prevents data loss

Prerequisites

Before running this application, ensure you have:

• Node.js (version 14.0.0 or higher)
• npm (Node Package Manager)

You can check your versions by running:

node --version
npm --version

Installation

1. Clone the repository

   git clone <repository-url>
   cd task-manager

2. Install dependencies

   npm install

3. Run the application

   npm start

Development Setup

For development work, you can use these additional commands:

# Install development dependencies
npm install --dev

# Run with auto-restart during development
npm run dev

# Run tests
npm test

# Code linting
npm run lint

# Code formatting
npm run format

Usage

Getting Started

1. Launch the application:

   npm start

2. You'll see the main menu with numbered options. Enter the number corresponding to your desired action.

📺 For a complete visual guide, watch our video walkthrough showing all features in action.

Main Menu Options

Option	Description
1	Add Task - Create a new task with full details
2	View All Tasks - Display all tasks in your list
3	View Tasks by Filter - Filter tasks by various criteria
4	Update Task - Modify existing task properties
5	Delete Task - Remove tasks from your list
6	Toggle Task Completion - Mark tasks as complete/incomplete
7	Search Tasks - Find tasks using keywords
8	Task Statistics - View productivity analytics
9	Export/Import - Backup or restore task data
0	Exit - Close the application

Creating Tasks

When adding a new task, you'll be prompted to enter:

• Title (required): A brief name for your task
• Description (optional): Detailed information about the task
• Priority (optional): High, Medium, or Low (default: Medium)
• Due Date (optional): Deadline in YYYY-MM-DD format
• Category (optional): Custom category for organization (default: General)
• Task Type: Choose between Regular, Work, or Personal tasks

Filtering Tasks

You can filter tasks by:

• Category: Show tasks from specific categories
• Priority: Filter by High, Medium, or Low priority
• Status: Show completed or incomplete tasks
• Overdue Tasks: Display tasks past their due date
• Due Soon: Show tasks due within the next 7 days

Searching Tasks

Use the search function to find tasks by entering keywords that match:

• Task titles
• Task descriptions
• Categories

Project Structure

task-manager/
├── index.js              # Main application entry point
├── src/                  # Source code directory
│   ├── Task.js          # Task class and specialized classes
│   ├── TaskManager.js   # Main task management logic
│   ├── FileHandler.js   # File I/O operations
│   ├── Validator.js     # Data validation utilities
│   └── CLI.js           # Command-line interface
├── package.json          # Project configuration and dependencies
├── README.md            # This documentation file
├── tasks.json           # Task data storage (auto-generated)
├── tasks_backup.json    # Automatic backup file (auto-generated)
├── tests/               # Test files directory
│   ├── task.test.js     # Task class tests
│   ├── taskManager.test.js # TaskManager tests
│   ├── fileHandler.test.js # File operations tests
│   └── validator.test.js # Validation tests
├── docs/                # Additional documentation
└── exports/             # Directory for exported task files

Object-Oriented Design

This application demonstrates key OOP principles through its class structure:

Core Classes

Task Class

The base class for all tasks with encapsulation using private fields:

class Task {
    // Private fields for data protection
    #id; #title; #description; #priority; #dueDate; 
    #category; #completed; #createdAt;
    
    // Public methods for controlled access
    markComplete()
    markIncomplete()
    isOverdue()
    getDaysUntilDue()
    // ... getters and setters
}

Specialized Task Classes

Inheritance is demonstrated through specialized task types:

class WorkTask extends Task {
    // Work-specific properties and methods
}

class PersonalTask extends Task {
    // Personal task specific features
}

TaskManager Class

Handles all task management operations:

class TaskManager {
    addTask(taskData)
    updateTask(id, updates)
    deleteTask(id)
    searchTasks(keyword)
    filterTasks(criteria)
    sortTasks(sortBy)
    getTaskStats()
    exportTasks(filename)
    importTasks(filename)
}

FileHandler Class

Manages all file operations:

class FileHandler {
    loadTasks()
    saveTasks(tasks)
    createBackup()
    exportTasks(tasks, filename)
    importTasks(filename)
}

Validator Class

Handles data validation and sanitization:

class Validator {
    validateTaskData(data)
    validateId(id)
    sanitizeInput(input)
    isValidDate(dateString)
}

CLI Class

Manages the command-line interface:

class CLI {
    showMainMenu()
    handleMenuChoice(choice)
    addTaskFlow()
    updateTaskFlow()
    deleteTaskFlow()
}

OOP Principles Demonstrated

Encapsulation: Private fields protect data integrity, with controlled access through public methods.

Inheritance: Specialized task classes inherit from the base Task class, promoting code reuse.

Polymorphism: Different task types can be handled uniformly through the same interface.

Abstraction: Complex operations are hidden behind simple, intuitive method calls.

Data Storage

File Format

Tasks are stored in JSON format in the tasks.json file:

[
  {
    "id": "task_1234567890_abc123",
    "title": "Complete project documentation",
    "description": "Write comprehensive README and setup guide",
    "priority": "High",
    "dueDate": "2024-12-15T00:00:00.000Z",
    "category": "Work",
    "completed": false,
    "createdAt": "2024-12-01T10:30:00.000Z"
  }
]

Backup System

• Automatic backup creation before each save operation
• Backup stored in tasks_backup.json
• Automatic recovery if main file becomes corrupted
• Manual export/import for additional backups

Error Handling

The application includes comprehensive error handling for:

• File operation failures
• Invalid user input
• Data corruption
• Network issues (future cloud integration)
• Date format validation

Testing

Running Tests

Execute the test suite with:

npm test

Test Coverage

Tests cover:

• Task class methods and properties
• TaskManager CRUD operations
• File handling and backup systems
• Search and filter functionality
• Data validation and sanitization
• Error handling scenarios

Writing New Tests

When adding new features, ensure you:

1. Write unit tests for new methods
2. Test error conditions
3. Verify data persistence
4. Test user input validation

Performance Considerations

• Efficient Search: Optimized algorithms for filtering and searching large task lists
• Memory Management: Proper cleanup of objects and resources
• File I/O: Minimized disk operations through intelligent caching
• Error Recovery: Graceful handling of failures without data loss

Security Features

• Input Sanitization: All user inputs are validated and sanitized
• File Path Validation: Safe file operations prevent path traversal attacks
• Data Integrity: Validation ensures data consistency
• Error Messages: Secure error reporting without exposing sensitive information

Contributing

We welcome contributions! Please follow these steps:

1. Fork the repository
2. Create a feature branch

   git checkout -b feature/your-feature-name

3. Make your changes
4. Write or update tests
5. Ensure all tests pass

   npm test

6. Commit your changes

   git commit -m "Add: brief description of changes"

7. Push to your fork

   git push origin feature/your-feature-name

8. Create a Pull Request

Code Style Guidelines

• Use meaningful variable and function names
• Follow existing code formatting
• Add comments for complex logic
• Write tests for new features
• Update documentation as needed

Future Enhancements

Planned features for upcoming versions:

• 📱 Web-based interface
• 🔄 Real-time collaboration
• 📊 Advanced analytics dashboard
• 🔔 Due date notifications
• ☁️ Cloud storage integration
• 📱 Mobile companion app
• 🔗 Third-party integrations (Google Calendar, Slack)

Troubleshooting

Common Issues

Application won't start

• Ensure Node.js is installed and updated
• Run npm install to install dependencies
• Check for error messages in the console

Tasks not saving

• Verify write permissions in the application directory
• Check available disk space
• Look for backup files if main storage fails

Invalid date formats

• Use YYYY-MM-DD format for dates
• Ensure dates are realistic (not in the past for due dates)

Search not working

• Check for typos in search terms
• Try broader search terms
• Ensure tasks exist in the specified category

License

This project is licensed under the MIT License. See the LICENSE file for details.

Support

For questions, bug reports, or feature requests:

• 📧 Contact the development team through your course platform
• 🐛 Create an issue on the project repository
• 📖 Check the documentation in the docs/ directory
• 🎥 Watch the video walkthrough for visual guidance

Acknowledgments

• Course instructors for guidance on OOP principles and best practices
• Node.js community for excellent documentation and tools
• Team members for collaborative development and peer review
• Beta testers for valuable feedback and suggestions

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Task Manager v1.0.0 - Built with ❤️ by Team Task Masters