COVID-19 Health Declaration System

Enterprise-grade web application for COVID-19 health record management with comprehensive analytics, security hardening, and freemium model

🖼️ Screenshots

🏠 Landing Page

Modern, accessible landing page with clear call-to-action and guest usage tracking

🔐 Authentication

Secure authentication with rate limiting and session management

📊 Analytics Dashboard

Comprehensive health analytics with real-time KPIs, time-range filtering, and trend analysis

📋 Records Management

Advanced table interface with search, filtering, and bulk operations

✨ Key Features

🏢 Enterprise Security

• SQL Injection Protection - All queries use prepared statements
• CSRF Protection - Comprehensive token validation
• XSS Prevention - Input sanitization and output encoding
• Session Security - Secure configuration with timeout and regeneration
• Rate Limiting - Protection against brute force attacks
• Security Logging - Comprehensive audit trail

💎 Freemium Model

• Guest Access - 3 submissions/day with IP-based tracking
• Premium Users - Unlimited access for authenticated users
• Usage Analytics - Real-time tracking and upgrade prompts
• Daily Reset - Automated via Windows Task Scheduler

📊 Advanced Analytics

• Real-time KPIs - Total records, encounters, vaccinations, temperatures
• Time-based Filtering - Today, 7 days, 30 days, all time
• Trend Analysis - Period-over-period comparisons
• Export Capabilities - CSV export with current filters
• Quick Filters - Vaccinated, encountered, fever, today

🎨 Modern UX/UI

• Dark Theme - Professional healthcare-focused design
• Mobile-First - Responsive design with touch-friendly interactions
• Accessibility - WCAG 2.1 AA compliance with keyboard navigation
• Loading States - Smooth transitions and feedback
• Dynamic Navigation - Scroll-based transparency and blur effects

🚀 Quick Start

Prerequisites

• XAMPP (Apache, MySQL, PHP 7.4+)
• Git

Installation

# Clone the repository
git clone https://github.com/transcenddev/covid-health-declaration.git

# Move to XAMPP directory
mv covid-health-declaration C:/xampp/htdocs/

# Import database schema
mysql -u root -p < database/covid19recordsdb.sql
mysql -u root -p < database/add_created_at_column.sql
mysql -u root -p < database/freemium_migration.sql

# Optional: Add performance indexes
mysql -u root -p < database/performance_indexes.sql

Access Application

• URL: http://localhost/covid-health-declaration/
• Admin Login: Username: Admin, Password: Admin
• Guest Access: Use incognito/private browsing to test freemium limits

🏗️ Architecture

Core Components

• Frontend: HTML5, CSS3 (Grid/Flexbox), ES6 JavaScript classes
• Backend: PHP with MySQLi prepared statements
• Database: MySQL with optimized indexes and relationships
• Security: Custom security layer with comprehensive protection
• Freemium: IP-based usage tracking with automated reset

File Structure

covid-health-declaration/
├── includes/           # Core PHP modules
│   ├── security.inc.php    # Security functions
│   ├── freemium.inc.php    # Usage tracking
│   └── dbconn.inc.php      # Database connection
├── database/          # SQL schema and migrations
├── styles/           # Modular CSS architecture
├── scripts/          # ES6 JavaScript modules
├── logs/            # Security and error logs
└── .github/         # AI coding instructions

🔧 Development

Security-First Development

All code follows strict security patterns:

• Prepared statements for all database queries
• CSRF tokens in all forms
• Input sanitization and validation
• Secure session configuration
• Comprehensive error logging

Debugging

• Error Logs: logs/php_errors.log
• Security Events: logs/security.log
• Freemium Tracking: logs/freemium.log

🚀 Production Deployment

Daily Maintenance

Set up Windows Task Scheduler:

Program: C:\xampp\php\php.exe
Arguments: C:\xampp\htdocs\covid-health-declaration\reset_daily_limits.php
Schedule: Daily at 00:01

Security Monitoring

• Monitor logs/security.log for suspicious activity
• Regular database backups
• Keep PHP and MySQL updated

🤝 Contributing

1. Fork the repository
2. Create a feature branch (git checkout -b feature/amazing-feature)
3. Follow security-first development patterns
4. Commit changes (git commit -m 'Add amazing feature')
5. Push to branch (git push origin feature/amazing-feature)
6. Open a Pull Request

Development Guidelines

• Always use prepared statements for database queries
• Include CSRF protection in forms
• Follow the existing code architecture
• Add comprehensive error logging
• Test freemium functionality with multiple IP addresses

📄 License

MIT License - see LICENSE file for details

🙏 Acknowledgments

• Built with security-first principles
• Designed for healthcare environments
• Optimized for accessibility and mobile use

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