calendar/integration_plan.md

RFC 5545 Integration Plan

Phase 1: Core Structure Replacement (High Impact, Low Risk)

1.1 Replace Event Models

Files to Update:

• backend/src/calendar.rs - Replace CalendarEvent with VEvent
• src/services/calendar_service.rs - Replace CalendarEvent with VEvent
• Remove duplicate structures, use single source of truth

Benefits:

• ✅ Eliminate duplicate event definitions
• ✅ Add missing DTSTAMP (RFC required)
• ✅ Add SEQUENCE for proper versioning
• ✅ Standardize on DateTime instead of string parsing

1.2 Simplify Request/Response Models

Files to Update:

• backend/src/models.rs - Replace string-based fields

Current (Complex):

pub start_date: String,        // YYYY-MM-DD format
pub start_time: String,        // HH:MM format  
pub categories: String,        // comma-separated
pub attendees: String,         // comma-separated

New (Simple):

pub dtstart: DateTime<Utc>,
pub categories: Vec<String>,
pub attendees: Vec<Attendee>,

Benefits:

• ✅ Remove ~50 lines of manual string parsing in handlers
• ✅ Better type safety
• ✅ Automatic validation

Phase 2: Enhanced Functionality (Medium Impact, Medium Risk)

2.1 Add Rich Attendee Support

Current: Vec<String> (just emails) New: Vec<Attendee> with roles, status, RSVP

Benefits:

• ✅ Proper meeting invitations
• ✅ RSVP tracking
• ✅ Role-based permissions (Chair, Required, Optional)

2.2 Structured Reminders/Alarms

Current: Simple reminder minutes New: Full VAlarm component with actions, triggers

Benefits:

• ✅ Multiple reminder types (email, display, audio)
• ✅ Complex trigger patterns
• ✅ Better CalDAV compatibility

2.3 Geographic Location Support

New Addition: GEO property for latitude/longitude

Benefits:

• ✅ Map integration possibilities
• ✅ Location-based reminders
• ✅ Travel time calculations

Phase 3: Advanced Components (High Impact, Higher Risk)

3.1 Add VTODO Support

New Component: Task/To-Do management

Benefits:

• ✅ Unified calendar + task system
• ✅ Due dates, completion tracking
• ✅ Priority management

3.2 Add VJOURNAL Support

New Component: Journal/diary entries

Benefits:

• ✅ Meeting notes integration
• ✅ Daily journaling
• ✅ Full calendar suite

3.3 Add VFREEBUSY Support

New Component: Availability tracking

Benefits:

• ✅ Meeting scheduling optimization
• ✅ Conflict detection
• ✅ Resource booking

Implementation Strategy

Immediate Actions (Can Start Now)

1. Add compatibility layer in existing CalendarEvent to support new fields
2. Implement conversion functions between old/new structures
3. Update backend models to use DateTime instead of string parsing

Quick Wins (1-2 hours each)

1. Replace string date parsing in backend/src/handlers.rs
2. Add missing DTSTAMP to all events (RFC compliance)
3. Convert categories/attendees from comma-separated strings to vectors

Medium Effort (3-5 hours each)

1. Unified event structure across frontend/backend
2. Rich attendee management with roles and status
3. Structured alarm system

Long Term (Future enhancements)

1. Full VTODO implementation
2. VJOURNAL support
3. VFREEBUSY and scheduling

Risk Mitigation

Backward Compatibility

• Keep existing API endpoints working
• Add conversion functions between old/new formats
• Gradual migration, not big-bang replacement

Testing Strategy

• Add tests for RFC 5545 compliance
• Test CalDAV interoperability
• Validate against multiple calendar clients

Rollback Plan

• Keep old structures as fallback
• Feature flags for new functionality
• Incremental deployment

Expected Benefits

Developer Experience

• 50% reduction in date/time parsing code
• Elimination of string-based field parsing
• Type safety for all calendar operations
• Standards compliance reduces debugging

User Experience

• Better CalDAV compatibility with all clients
• Rich attendee management for meetings
• Proper timezone handling
• Future-proof for advanced features

Maintenance

• Single source of truth for event data
• RFC 5545 compliance eliminates compatibility issues
• Cleaner codebase with less duplication
• Easier testing with structured data

File Impact Analysis

High Impact Files (Need Updates)

backend/src/models.rs       - Replace request/response structs
backend/src/handlers.rs     - Remove string parsing logic
backend/src/calendar.rs     - Replace CalendarEvent
src/services/calendar_service.rs - Use unified structures

Medium Impact Files (Minor Changes)

src/components/create_event_modal.rs - Update form handling
src/components/event_modal.rs        - Display enhancements
backend/src/lib.rs                   - Add new modules

Low Impact Files (Minimal/No Changes)

src/components/week_view.rs   - Just use new event structure
src/components/month_view.rs  - Just use new event structure
styles.css                   - No changes needed

Next Steps

1. Review this plan with team/stakeholders
2. Create branch for RFC 5545 integration
3. Start with Phase 1.1 - Core structure replacement
4. Implement conversion functions for compatibility
5. Update one handler at a time to reduce risk

The integration will significantly simplify the codebase while adding professional-grade calendar functionality!