fete/specs/009-list-events/data-model.md

Data Model: Event List on Home Page

Feature: 009-list-events | Date: 2026-03-08

Entities

StoredEvent (existing — no changes)

The StoredEvent interface in frontend/src/composables/useEventStorage.ts already contains all fields needed for the event list feature.

interface StoredEvent {
  eventToken: string        // Required — UUID, used for navigation
  organizerToken?: string   // Present if user created this event
  title: string             // Required — displayed on card
  dateTime: string          // Required — ISO 8601, used for sorting + relative time
  expiryDate: string        // Stored but not displayed in list view
  rsvpToken?: string        // Present if user RSVP'd to this event
  rsvpName?: string         // User's name at RSVP time
}

Validation Rules

An event entry is considered valid for display if all of:

• eventToken is a non-empty string
• title is a non-empty string
• dateTime is a non-empty string that parses to a valid Date

Invalid entries are silently excluded from the list (FR-010).

Derived Properties (computed at render time)

Property	Derivation
isPast	new Date(dateTime) < new Date()
isOrganizer	organizerToken !== undefined
isAttendee	rsvpToken !== undefined && organizerToken === undefined
relativeTime	Intl.RelativeTimeFormat applied to dateTime vs now
detailRoute	/events/${eventToken}

Sorting Order

1. Upcoming events (dateTime >= now): ascending by dateTime (soonest first)
2. Past events (dateTime < now): descending by dateTime (most recently passed first)

Composable Extension

The useEventStorage composable needs one new function:

function removeEvent(eventToken: string): void {
  const events = readEvents().filter((e) => e.eventToken !== eventToken)
  writeEvents(events)
}

Returned alongside existing functions from useEventStorage().

State Transitions

localStorage read
       │
       ▼
  Parse JSON ──(error)──► empty array
       │
       ▼
  Validate entries ──(invalid)──► silently excluded
       │
       ▼
  Split: upcoming / past
       │
       ▼
  Sort each group
       │
       ▼
  Concatenate ──► rendered list

Remove Event Flow

User taps delete icon / swipes left
       │
       ▼
  ConfirmDialog opens
       │
  ┌────┴────┐
  │ Cancel  │  Confirm
  │         │     │
  │         ▼     ▼
  │    removeEvent(token)
  │         │
  │         ▼
  │    Event removed from localStorage
  │    List re-renders (event disappears)
  └────────────────────────────────┘