"""
Security audit results and recommendations for Church Music Database

Date: December 15, 2025
Audit Type: Full-stack security and code quality review

## CRITICAL ISSUES FIXED

### Backend (Python/Flask)

✅ 1. Database Session Leaks - FIXED

- Added try-finally blocks to all endpoints
- Implemented proper session cleanup
- Fixed get_db() function to prevent premature closure

✅ 2. Input Validation - FIXED

- Added length limits on all string inputs (title, artist, name: 500 chars)
- Added file size validation (10MB max)
- Added filename validation to prevent path traversal
- Added query parameter length limits (500 chars)
- Added ID validation for all endpoints

✅ 3. SQL Injection Protection - ENHANCED

- Already using SQLAlchemy ORM (parameterized queries)
- Added input sanitization
- Added validation on filter types in search

✅ 4. Security Headers - ADDED

- X-Content-Type-Options: nosniff
- X-Frame-Options: DENY
- X-XSS-Protection: 1; mode=block
- Strict-Transport-Security (HSTS)
- Server header removal

✅ 5. Request Size Limits - ADDED

- MAX_CONTENT_LENGTH: 16MB
- File upload: 10MB limit
- Prevents DoS attacks

✅ 6. Session Security - ENHANCED

- Secure cookie flags in production
- HTTPOnly flag set
- SameSite=Lax
- Session timeout: 1 hour

✅ 7. Environment Variables - VALIDATED

- Added production checks for SECRET_KEY and POSTGRESQL_URI
- Created .env.example template
- Added warning for default passwords

### Database (PostgreSQL)

✅ 8. Indexes Added for Performance

- idx_profile_name on profiles(name)
- idx_song_title, idx_song_artist, idx_song_band on songs
- idx_plan_date, idx_plan_profile on plans
- Composite indexes on junction tables

✅ 9. Unique Constraints Added

- uq_plan_song (prevents duplicate songs in plans)
- uq_profile_song (prevents duplicate profile-song associations)
- uq_profile_song_key (one key per profile-song)

✅ 10. Cascade Deletes Configured

- ON DELETE CASCADE for ProfileSong, ProfileSongKey, PlanSong
- ON DELETE SET NULL for Plan.profile_id
- Prevents orphaned records

✅ 11. Password Validation - ADDED

- Checks for default password in production
- Raises error if 'your_password' found in POSTGRESQL_URI

### Frontend (React)

✅ 12. Error Handling - IMPROVED

- Better error logging in API settings parsing
- Automatic corrupted settings cleanup
- Graceful fallbacks throughout

## REMAINING RECOMMENDATIONS

### High Priority

⚠️ 1. Authentication Enhancement

- Current: Client-side password hash (easily bypassed)
- Recommended: JWT tokens with backend authentication
- Recommended: OAuth2 or SAML for enterprise

⚠️ 2. Rate Limiting

- Install flask-limiter: pip install flask-limiter
- Add rate limits to prevent brute force attacks
- Suggested: 100 requests per minute per IP

⚠️ 3. HTTPS/TLS Configuration

- Currently using HTTP
- Production MUST use HTTPS
- Configure reverse proxy (nginx) with Let's Encrypt certificates

⚠️ 4. Content Security Policy (CSP)

- Add CSP headers to prevent XSS attacks
- Restrict script sources to same-origin

### Medium Priority

⚠️ 5. Code Organization

- App.js is 7579 lines (too large)
- Recommended: Split into smaller components
- Implement proper component structure

⚠️ 6. API Versioning

- Add /api/v1/ prefix to all endpoints
- Allows backward compatibility during updates

⚠️ 7. Logging Enhancement

- Implement structured logging (JSON format)
- Add request ID tracking
- Log security events (failed auth, suspicious activity)

⚠️ 8. Database Backup Strategy

- Implement automated daily backups
- Test restore procedures
- Store backups offsite

### Low Priority

⚠️ 9. Performance Optimization

- Add Redis caching for frequently accessed data
- Implement pagination for large result sets
- Add database query caching

⚠️ 10. Monitoring

- Add application monitoring (Sentry, New Relic)
- Database performance monitoring
- Uptime monitoring

## DEPLOYMENT CHECKLIST

Before deploying to production:
□ Change all default passwords
□ Set SECRET_KEY environment variable
□ Enable HTTPS/TLS
□ Configure firewall rules
□ Set up database backups
□ Run migrate_database.py to add indexes
□ Test all endpoints
□ Review logs for errors
□ Set FLASK_ENV=production
□ Disable debug mode
□ Configure reverse proxy (nginx/Apache)

## MAINTENANCE TASKS

Weekly:

- Review application logs
- Check database size
- Monitor failed login attempts

Monthly:

- Update dependencies (pip, npm)
- Review and rotate secrets
- Test backup restore procedure

Quarterly:

- Security audit
- Performance review
- Dependency vulnerability scan

## FILES CREATED/MODIFIED

✅ Modified:

- backend/app.py (security fixes, session management)
- backend/postgresql_models.py (indexes, constraints)
- frontend/src/api.js (error handling)

✅ Created:

- .env.example (environment template)
- backend/migrate_database.py (database migration script)
- SECURITY_AUDIT.md (this file)

## TESTING COMMANDS

# Test backend endpoints

curl <http://localhost:8080/api/health>

# Check database connections

python -c "from backend.postgresql_models import engine; print(engine.connect())"

# Run migration

cd backend && python migrate_database.py

# Install updated dependencies

cd backend && pip install -r requirements.txt
cd frontend && npm install

## SUPPORT

For questions or issues, refer to:

- CONFIGURATION_GUIDE.md
- POSTGRESQL_SETUP_COMPLETE.md
- QUICK_REFERENCE.md
"""