# TimeSafari Notification System — Strategic Plan

**Status:** 🚀 Active plan
**Date:** 2025-09-05T05:09Z (UTC)
**Author:** Matthew Raymer
**Scope:** v1 (in‑app orchestrator) now; path to v2 (native plugin) next
**Goal:** We **will deliver** 1..M local notifications/day with content
**prefetched** so messages **will display offline**. We **will support**
online‑first (API→DB→Schedule) with offline‑first fallback. The system
**will enhance** TimeSafari's community-building mission by keeping users
connected to gratitude, gifts, and collaborative projects through timely,
relevant notifications.

> **Implementation Details:** See `notification-system-implementation.md` for
 detailed code, database schemas, and integration specifics.
> **Canonical Ownership:** This document owns Goals, Tenets, Platform
> behaviors, Acceptance criteria, and Test cases.

---

## 1) Versioning & Intent

- **v1 (In‑App Orchestrator):** We **will implement** multi‑daily local
  notifications, online/offline flows, templating, SQLite persistence, and
  eventing **inside the app** using Capacitor Local Notifications.
- **v2 (Plugin):** We **will extract** adapters to a Capacitor/Native plugin
  to gain native schedulers (WorkManager/AlarmManager;
  BGTask+UNUserNotificationCenter), native HTTP, and native SQLite **with the
  same TypeScript API**.

> We **will retain** the existing web push + Service Worker foundation; the
> system **will add** reliable local scheduling on mobile and a unified API
> across platforms.

---

## 2) Design Tenets

- **Reliability:** OS‑level delivery once scheduled; no reliance on JS being alive
at fire time.
- **Freshness:** Prefer online‑first within a short prefetch window; degrade
gracefully to cached content with TTL.
- **Extractable:** Clean interfaces (Scheduler, DataStore, Callbacks) so v2
**will swap** adapters without API changes.
- **Simplicity:** One‑shot notifications per slot; rolling window scheduling to
respect platform caps.
- **Observability:** Persist deliveries and errors; surface minimal metrics;
enable ACKs.
- **Privacy-First:** Follow TimeSafari's privacy-preserving architecture;
user-controlled visibility and data sovereignty.
- **Community-Focused:** Enhance TimeSafari's mission of connecting people through
gratitude, gifts, and collaborative projects.

---

## 3) Architecture Overview

```
Application (Vue/TS)
 ├─ NotificationOrchestrator (core state)
 │   ├─ Scheduler (adapter)
 │   ├─ DataStore (adapter)
 │   └─ Callbacks (adapter)
 └─ UI (settings, status)

Adapters
 ├─ V1: SchedulerCapacitor, DataStoreSqlite, CallbacksHttp
 └─ V2: SchedulerNative, DataStoreNativeSqlite, CallbacksNativeHttp

**Scheduler Adapter:** All notification arming must go through the Scheduler adapter to honor platform timing semantics (exact alarms vs. windowed fallback).

Platform
 ├─ iOS/Android: LocalNotifications (+ native bridges later)
 ├─ Web: Service Worker + Push (kept)
 └─ Electron: OS notifications (thin adapter)
```

**Execution modes (concise):**

- **Online‑First:** wake near slot → fetch (ETag, timeout) → persist → schedule;
on failure → Offline‑First.
- **Offline‑First:** read last good payload from SQLite; if beyond TTL → skip
notification (no retry).

---

## 4) Public API (Shared by v1 & v2)

**Core Types & Interface:** See Implementation document for complete API 
definitions, type interfaces, and design decisions.

> **Storage semantics:** `'shared'` = app DB; `'private'` = plugin-owned/native
> DB (v2). (No functional difference in v1.)
> **Slot Identity & Scheduling Policy**
> • **SlotId** uses canonical `HHmm` and remains stable across timezone
> changes.
> • **Lead window:** default `prefetchLeadMinutes = 20`; no retries once inside
 the lead.
> • **TTL policy:** When offline and content is beyond TTL, **we will skip** the
notification (no "(cached)" suffix).
> • **Idempotency:** Duplicate "scheduled" deliveries are prevented by a unique
index on `(slot_id, fire_at, status='scheduled')`.
> • **Time handling:** Slots will follow **local wall-clock** time across TZ/DST;
`slotId=HHmm` stays constant and we will **recompute fire times** on offset change.

---

## 5) Data Model & Retention (SQLite)

**Tables:** `notif_contents`, `notif_deliveries`, `notif_config` (see 
Implementation document for complete schema)

**Retention:** We **will keep** ~14 days of contents/deliveries (configurable) 
and **will prune** via a simple daily job that runs on app start/resume. We 
**will prune** daily but **will not** VACUUM by default on mobile; disk 
compaction is deferred.

**Payload handling:** We **will template** `{title, body}` **before** scheduling; 
we **will not** mutate at delivery time.

---

## 6) Scheduling Policy & Slot Math

- **One‑shot per slot** per day (non‑repeating).
- **Rolling window:** today's remaining slots; seed tomorrow where platform 
limits allow.
- **TZ/DST safe:** We **will recompute** local wall‑times on app resume and 
whenever timezone/offset changes; then **reschedule**.
- **Android exactness:** If exact alarms are unavailable or denied, we 
**will use** `setWindow` semantics via the scheduler adapter.
- **iOS pending cap:** We **will keep** pending locals within typical caps (~64) 
by limiting the window and canceling/re‑arming as needed.
- **Electron rolling window:** On Electron we **will schedule** the **next 
occurrence per slot** by default; depth (today+tomorrow) **will be** enabled only 
when auto-launch is on, to avoid drift while the app is closed.

---

## 7) Timing & Network Requirements

**Summary:** The notification system uses lightweight, ETag-aware content 
fetching with single attempts inside lead windows. All timing constants and 
detailed network policies are defined in the Implementation document.

**Key Policies:**

- **Lead policy:** The lead window governs **online-first fetch attempts**, not 
arming. We **will arm** locals **whenever the app runs**, using the freshest 
available payload.
- **TTL policy:** If offline and content is beyond TTL, we will **skip** the 
notification (no "cached" suffix).
- **Idempotency:** Duplicate "scheduled" rows are prevented by a unique index on 
`(slot_id, fire_at, status='scheduled')`.
- **Wall-clock rule:** Slots will follow **local wall-clock** across TZ/DST; 
`slotId=HHmm` stays constant and we will **recompute fire times** on offset change.
- **Resume debounce:** On app resume/open we will **debounce** pipeline 
entry points by **30s** per app session to avoid burst fetches.
- **No scheduled background network in v1 (mobile):** Local notifications 
**will deliver offline once armed**, but **we will not** run timed network jobs 
when the app is terminated. **Network prefetch will occur only while the app is 
running** (launch/resume/inside lead). Server-driven push (Web SW) and OS 
background schedulers are a **v2** capability.

**Platform-Specific Network Access:**

- **iOS:** Foreground/recently backgrounded only; no JS wake when app is killed
- **Android:** Exact alarms vs. windowed triggers based on permissions
- **Web:** Service Worker for push notifications only
- **Electron:** App-running only; no background network access

**Optional Background Prefetch (v1):**

- **Background Runner (optional, v1):** We **will integrate** Capacitor's
Background Runner to **opportunistically prefetch** content on iOS/Android when
the OS grants background time. This **will not** provide clock-precise execution
and **will not** run after user-terminate on iOS. It **will not** be treated as
a scheduler. We **will continue** to *arm* local notifications via our rolling
window regardless of Runner availability. When Runner fires near a slot (inside
`prefetchLeadMinutes`), it **will** refresh content (ETag, 12s timeout) and,
behind a flag, **may** cancel & re-arm that slot with the fresh template if within
TTL. If no budget or failure, the previously armed local **will** still deliver.

**Implementation Details:** See Implementation document for complete timing 
constants table, network request profiles, and platform-specific enforcement.

---

## 8) Platform Essentials

**iOS**

- Local notifications **will** fire without background runtime once scheduled.
NSE **will not** mutate locals; delivery-time enrichment requires remote push (future).
- **Category ID**: `TS_DAILY` with default `OPEN` action
- **Background budget** is short and OS‑managed; any prefetch work
**will complete** promptly.
- **Mobile local notifications will route via action listeners (not the service worker)**.
- Background Runner **will** offer **opportunistic** network wake (no guarantees;
short runtime; iOS will not run after force-quit). Locals **will** still deliver
offline once armed.

**Android**

- Exact alarms on **API 31+** may require `SCHEDULE_EXACT_ALARM`. If exact access
is missing on API 31+, we will use a **windowed trigger (default ±10m)** and
surface a settings deep-link.
- **We will deep-link users to the exact-alarm settings when we detect denials.**
- **Channel defaults**: ID `timesafari.daily`, name "TimeSafari Daily",
importance=high (IDs never change)
- Receivers for reboot/time change **will be handled** by v2 (plugin); in v1,
re‑arming **will occur** on app start/resume.
- **Mobile local notifications will route via action listeners (not the service worker)**.
- Background Runner **will** offer **opportunistic** network wake (no guarantees;
short runtime; iOS will not run after force-quit). Locals **will** still deliver
offline once armed.

**Web**

- Requires registered Service Worker + permission; can deliver with browser closed.
**Web will not offline-schedule**.
- Service Worker click handlers are for **web push only**;
**mobile locals bypass the SW**.
- SW examples use `/sw.js` as a placeholder; **wire this to your actual build
output path** (e.g., `sw_scripts/notification-click.js` or your combined bundle).
- **Note**: Service workers are **intentionally disabled** in Electron
(`src/main.electron.ts`) and web uses VitePWA plugin for minimal implementation.

**Electron**

- We **will use** native OS notifications with **best-effort scheduling while the
app is running**; true background scheduling will be addressed in v2 (native bridges).

**Electron delivery strategy (v1 reality + v2 path)**
We **will deliver** desktop notifications while the Electron app is running. True
**background scheduling when the app is closed** is **out of scope for v1** and
**will be addressed** in v2 via native bridges. We **will adopt** one of the
following options (in order of fit to our codebase):

**In-app scheduler + auto-launch (recommended now):** Keep the orchestrator in
the main process, **start on login** (tray app, hidden window), and use the
**Electron `Notification` API** for delivery. This requires no new OS services
and aligns with our PlatformServiceFactory/mixin patterns.

**Policy (v1):** If the app is **not running**, Electron will **not** deliver
scheduled locals. With **auto-launch enabled**, we **will achieve** near-mobile
parity while respecting OS sleep/idle behavior.

**UX notes:** On Windows we **will set** `appUserModelId` so toasts are
attributed correctly; on macOS we **will request** notification permission on
first use.

**Prerequisites:** We **will require** Node 18+ (global `fetch`) or we
**will polyfill** via `undici` for content fetching in the main process.

---

## 8) Template Engine Contract

**Supported tokens:** `{{headline}}`, `{{summary}}`, `{{date}}` (YYYY-MM-DD),
`{{time}}` (HH:MM).
**Escaping:** HTML-escape all injected values.
**Limits:** Title ≤ 50 chars; Body ≤ 200 chars; truncate with ellipsis.
**Fallback:** Missing token → `"[Content]"`.
**Mutation:** We **will** render templates **before** scheduling; no mutation at
delivery time on iOS locals.

## 9) Integration with Existing TimeSafari Infrastructure

**Database:** We **will integrate** with existing migration system in
`src/db-sql/migration.ts` following the established `MIGRATIONS` array pattern
**Settings:** We **will extend** existing Settings type in
`src/db/tables/settings.ts` following the established type extension pattern
**Platform Service:** We **will leverage** existing PlatformServiceMixin database
utilities following the established mixin pattern
**Service Factory:** We **will follow** the existing `PlatformServiceFactory`
singleton pattern for notification service creation
**Capacitor:** We **will integrate** with existing deep link system in
`src/main.capacitor.ts` following the established initialization pattern
**Service Worker:** We **will extend** existing service worker infrastructure
following the established `sw_scripts/` pattern (Note: Service workers are
intentionally disabled in Electron and have minimal web implementation via
VitePWA plugin)
**API:** We **will use** existing error handling from `src/services/api.ts`
following the established `handleApiError` pattern
**Logging:** We **will use** existing logger from `src/utils/logger` following
the established logging patterns
**Platform Detection:** We **will use** existing `process.env.VITE_PLATFORM`
patterns (`web`, `capacitor`, `electron`)
**Vue Architecture:** We **will follow** Vue 3 + vue-facing-decorator patterns
for component integration (Note: The existing `useNotifications` composable in
`src/composables/useNotifications.ts` is currently stub functions with
eslint-disable comments and needs implementation)
**State Management:** We **will integrate** with existing settings system via
`PlatformServiceMixin.$saveSettings()` for notification preferences (Note:
TimeSafari uses PlatformServiceMixin for all state management, not Pinia stores)
**Identity System:** We **will integrate** with existing `did:ethr:`
(Ethereum-based DID) system for user context
**Testing:** We **will follow** Playwright E2E testing patterns established in TimeSafari
**Database Architecture:** We **will support** platform-specific database backends:

- **Web**: Absurd SQL (SQLite via IndexedDB) via `WebPlatformService` with worker pattern
- **Capacitor**: Native SQLite via `CapacitorPlatformService`
- **Electron**: Native SQLite via `ElectronPlatformService` (extends CapacitorPlatformService)

---

## 10) Error Taxonomy & Telemetry

**Error Codes:** `FETCH_TIMEOUT`, `ETAG_NOT_MODIFIED`, `SCHEDULE_DENIED`,
`EXACT_ALARM_MISSING`, `STORAGE_BUSY`, `TEMPLATE_MISSING_TOKEN`, `PERMISSION_DENIED`.

**Event Envelope:** `code, slotId, whenMs, attempt, networkState, tzOffset,
appState, timestamp`.

---

## 11) Permission UX & Channels/Categories

- We **will request** notification permission **after** user intent (e.g.,
settings screen), not on first render.
- **Android:** We **will create** a stable channel ID (e.g., `timesafari.daily`)
and **will set** importance appropriately.
- **iOS:** We **will register** categories for optional actions; grouping may
use `threadIdentifier` per slot/day.

---

## 12) Eventing & Telemetry

**Error Codes:** `FETCH_TIMEOUT`, `ETAG_NOT_MODIFIED`, `SCHEDULE_DENIED`,
`EXACT_ALARM_MISSING`, `STORAGE_BUSY`, `TEMPLATE_MISSING_TOKEN`, `PERMISSION_DENIED`.

**Event Envelope:** `code, slotId, whenMs, attempt, networkState, tzOffset,
appState, timestamp`.

**Implementation:** See Implementation document for complete error taxonomy,
event logging envelope, ACK payload format, and telemetry events.

---

## 13) Feature Flags & Config

**Key Flags:** `scheduler`, `mode`, `prefetchLeadMinutes`, `ttlSeconds`,
`iosCategoryIdentifier`, `androidChannelId`, `prefetchRunner`, `runnerRearm`.

**Storage:** Feature flags **will reside** in `notif_config` table as key-value
pairs, separate from user settings.

**Implementation:** See Implementation document for complete feature flags table
 with defaults and descriptions.

---

## 14) Acceptance (Definition of Done) → Test Cases

### Explicit Test Checks

- **App killed → locals fire**: Configure slots at 8:00, 12:00, 18:00; kill
app; verify notifications fire at each slot on iOS/Android
- **ETag 304 path**: Server returns 304 → keep previous content; locals fire
with cached payload
- **ETag 200 path**: Server returns 200 → update content and re-arm locals with
fresh payload
- **Offline + beyond TTL**: When offline and content > 24h old → skip notification
(no "(cached)" suffix)
- **iOS pending cap**: Respect ~64 pending limit; cancel/re-arm as needed within
rolling window
- **Exact-alarm denied**: Android permission absent → windowed schedule (±10m)
activates; UI shows fallback hint
- **Permissions disabled** → we will record `SCHEDULE_DENIED` and refrain from
queuing locals.
- **Window fallback** → when exact alarm is absent on Android, verify target
fires within **±10m** of slot time (document as an E2E expectation).
- **Timezone change**: On TZ/DST change → recompute wall-clock times; cancel &
re-arm all slots
- **Lead window respect**: No retries attempted once inside 20min lead window
- **Idempotency**: Multiple `runFullPipelineNow()` calls don't create duplicate
scheduled deliveries
- **Cooldown guard**: `deliverStoredNow()` has 60s cooldown to prevent double-firing

### Electron-Specific Test Checks

- **Electron running (tray or window) → notifications fire** at configured slots
using Electron `Notification`
- **Electron not running →** no delivery (documented limitation for v1)
- **Start on Login enabled →** after reboot + login, orchestrator **will re-arm**
slots and deliver
- **Template limits honored** (Title ≤ 50, Body ≤ 200) on Electron notifications
- **SW scope** not used for Electron (click handlers are **web only**)
- **Windows appUserModelId** set correctly for toast attribution
- **macOS notification permission** requested on first use

### Timing-Verifiable Test Checks

- **iOS/Android (app killed):** locals will fire at their slots; no network
activity at delivery time.
- **iOS/Android (resume inside lead):** exactly **one** online-first attempt
occurs; if fetch completes within **12s** → content updated; otherwise offline
policy applies.
- **Android (no exact access):** observed delivery is within **±10 min** of slot
time.
- **Web push:** SW push event fetch runs once with **12s** timeout; if it times
out, the push still displays (from payload).
- **Electron (app running):** timer-based locals fire on time; on reboot with
**Start on Login**, orchestrator re-arms on first run.
- **TTL behavior:** offline & stale → **skip** (no notification posted).
- **ETag path:** with `304`, last payload remains; no duplicate scheduling rows
(unique index enforced).
- **Cooldown:** calling `deliverStoredNow` twice within **60s** for same slot
doesn't produce two notifications.
- **Closed app, armed earlier** → locals fire at slot; title/body match last
rendered content (proves "render at schedule time" + adapter API).
- **Closed app, timezone change before slot** → on next resume, app recomputes
and re-arms; already armed notifications will still fire on original wall-time
- **Mobile closed-app, no background network:** Arm at T–hours; kill app; verify
locals fire with last rendered text; confirm **no** network egress at delivery.
- **Web push as network scheduler:** Send push with empty payload → SW fetches
within 12s timeout → shows correct text; confirm behavior with browser closed.
- **Electron app not running:** No delivery; with **Start on Login**, after
reboot first run fetches and re-arms; subsequent slots fire.
- **Runner fires in background (Android/iOS):** With Runner enabled and app
backgrounded for ≥30 min, at least one prefetch **will** occur; content cache
**will** update; already-armed locals **will** still fire on time.
- **Runner re-arm (flagged):** If `runnerRearm=true` and Runner fires inside lead
with fresh content + within TTL, the system **will** cancel & re-arm the next
slot; delivered text **will** match fresh template.

---

## 15) Test Matrix (Essentials)

- **Android:** exact vs inexact branch, Doze/App Standby behavior, reboot/time
change, permission denial path, deep‑link to exact‑alarm settings.
- **iOS:** BG fetch budget limits, pending cap windowing, local notification
delivery with app terminated, category actions.
- **Web:** SW lifecycle, push delivery with app closed, click handling, no
offline scheduling.
- **Cross‑cutting:** ETag/304 behavior, TTL policy, templating correctness, event
 queue drain, SQLite retention job.

---

## 16) Migration & Rollout Notes

- We **will keep** existing web push flows intact.
- We **will introduce** the orchestrator behind a feature flag, initially with
a small number of slots.
- We **will migrate** settings to accept multiple times per day.
- We **will document** platform caveats inside user‑visible settings (e.g.,
Android exact alarms, iOS cap).

---

## 17) Security & Privacy

- Tokens **will reside** in Keystore/Keychain (mobile) and **will be injected**
at request time; they **will not** be stored in SQLite.
- Optionally, SQLCipher at rest for mobile; redaction of PII in logs; payload
size caps.
- Content **will be** minimal (title/body); sensitive data **will not be** embedded.

---

## 18) Non‑Goals (Now)

- Complex action sets and rich media on locals (kept minimal).
- Delivery‑time mutation of local notifications on iOS (NSE is for remote).
- Full analytics pipeline (future enhancement).

---

## 19) Cross-Doc Sync Hygiene

### Canonical Ownership

- **This document (Plan)**: Canonical for Goals, Tenets, Platform behaviors,
Acceptance criteria, Test cases
- **Implementation document**: Canonical for API definitions, Database schemas,
Adapter implementations, Code examples

### PR Checklist

When changing notification system behavior, update both documents:

- [ ] **API changes**: Update types/interfaces in both Plan §4 and Implementation §3
- [ ] **Schema changes**: Update Plan §5 and Implementation §2
- [ ] **Slot/TTL changes**: Update Plan §4 semantics and Implementation §6 logic
- [ ] **Template changes**: Update Plan §9 contract and Implementation examples
- [ ] **Error codes**: Update Plan §11 taxonomy and Implementation error handling

- **API code blocks**: Must be identical between Plan §4 and Implementation §3
(Public API (Shared))
- **Feature flags**: Must match between Plan §12 table and Implementation defaults
- **Test cases**: Plan §13 acceptance criteria must align with Implementation
test examples
- **Slot/TTL/Lead policies**: Must be identical between Plan §4 policy and
Implementation §3 policy

---

## Sync Checklist

| Sync item                      | Plan                  | Impl                  | Status |
| ------------------------------ | --------------------- | --------------------- | ------ |
| Public API block identical     | §4                    | §3                    | ✅     |
| `getState()` fields present    | §4                    | §8 Orchestrator       | ✅     |
| Capacitor action handlers      | §7 (iOS/Android note) | §9 Bootstrap          | ✅     |
| Electron fetch prereq/polyfill | §7                    | §9 Electron           | ✅     |
| Android ±10m fallback          | §7                    | §7 SchedulerCapacitor | ✅     |
| Retention (no VACUUM v1)       | §5                    | `$pruneNotifData`     | ✅     |
| Runner described as **opportunistic prefetch**, not scheduler | §7       | §9                       | ✅     |
| Feature flag `prefetchRunner` (default `'none'`)              | §13      | §15                      | ✅     |
| Capabilities `networkWake: 'opportunistic' | 'none'` | §7                       | Scheduler.capabilities | ✅     |
| Runner tick handler bounded to ≤12s                           | §7       | BackgroundRunnerPrefetch | ✅     |
| Optional `runnerRearm` flag & behavior                        | §7       | Orchestrator + Runner    | ✅     |

---

## Sync Checklist

| Sync item                      | Plan                  | Impl                  | Status |
| ------------------------------ | --------------------- | --------------------- | ------ |
| Public API block identical     | §4                    | §3                    | ✅     |
| `getState()` fields present    | §4                    | §8 Orchestrator       | ✅     |
| Capacitor action handlers      | §7 (iOS/Android note) | §9 Bootstrap          | ✅     |
| Electron fetch prereq/polyfill | §7                    | §9 Electron           | ✅     |
| Android ±10m fallback          | §7                    | §7 SchedulerCapacitor | ✅     |
| Retention (no VACUUM v1)       | §5                    | `$pruneNotifData`     | ✅     |
| Runner described as **opportunistic prefetch**, not scheduler | §7       | §9                       | ✅     |
| Feature flag `prefetchRunner` (default `'none'`)              | §13      | §15                      | ✅     |
| Capabilities `networkWake: 'opportunistic' | 'none'` | §7                       | Scheduler.capabilities | ✅     |
| Runner tick handler bounded to ≤12s                           | §7       | BackgroundRunnerPrefetch | ✅     |
| Optional `runnerRearm` flag & behavior                        | §7       | Orchestrator + Runner    | ✅     |

---

*This strategic plan focuses on features and future‑tense deliverables, avoids implementation details, and preserves a clear path from the in‑app orchestrator (v1) to native plugin (v2). For executive overview, see `notification-system-executive-summary.md`. For complete implementation details, see `notification-system-implementation.md`.*