---
phase: 04-inventory-expenses-and-financial-reports
plan: 02
subsystem: inventory
tags: [asset-management, serialized-tracking, disposal, write-off, journal-entry, location-history]

# Dependency graph
requires:
  - phase: 04-01
    provides: InventoryService.recordMovement, InventoryItem/StockMovement models, COA accounts 1200/2010
  - phase: 02-02
    provides: JournalEntryService.createEntry for disposal write-off JE
provides:
  - AssetService with assignToSubscriber, assignToTechnician, returnAsset, disposeAsset, getAssetHistory
  - API routes for assign, return, dispose, and history
  - Admin-only disposal with write-off JE (DR 5030, CR 1200)
  - Chronological location history with resolved names
affects: []

# Tech tracking
tech-stack:
  added: []
  patterns:
    - "Asset lifecycle builds on immutable movement ledger (no new models)"
    - "Role-based authorization at service layer (userRoles parameter)"
    - "Location name resolution via batch query + map lookup"

key-files:
  created:
    - src/lib/services/asset-service.ts
    - src/lib/__tests__/asset-service.test.ts
    - src/app/api/inventory/items/[id]/assign/route.ts
    - src/app/api/inventory/items/[id]/return/route.ts
    - src/app/api/inventory/items/[id]/dispose/route.ts
    - src/app/api/inventory/items/[id]/history/route.ts
  modified: []

key-decisions:
  - "AssetService delegates all movement recording to InventoryService.recordMovement — no direct StockMovement writes"
  - "Disposal JE created separately before movement record — InventoryService only auto-creates JEs for RECEIVED"
  - "getCurrentLocation derives from latest movement's to-fields (null for DISPOSED)"
  - "returnAsset always returns to main-warehouse — single warehouse model sufficient for ISP scale"
  - "History name resolution uses batch queries (subscribers + users) then Map lookup — avoids N+1"

patterns-established:
  - "Service-layer role check via userRoles array parameter (not CASL) for admin-only operations"

# Metrics
duration: 8min
completed: 2026-03-05
---

# Phase 4 Plan 2: Asset Management Summary

**Asset lifecycle on immutable movement ledger — assign to subscriber/technician, return with condition, admin-only disposal with write-off JE (DR 5030, CR 1200), chronological location history**

## Performance

- **Duration:** 8 min
- **Started:** 2026-03-05T05:03:22Z
- **Completed:** 2026-03-05T05:11:00Z
- **Tasks:** 2
- **Files created:** 6

## Accomplishments
- AssetService with full lifecycle: assign, return, dispose, history
- Admin-only disposal creates write-off JE (DR 5030 Equipment Expense, CR 1200 Equipment Inventory)
- Chronological location history with resolved subscriber/technician/warehouse names
- 11 integration tests all passing covering assignment, return, disposal auth, history, and full lifecycle

## Task Commits

Each task was committed atomically:

1. **Task 1: AssetService and API routes** - `eb29d6e` (feat)
2. **Task 2: Asset service tests** - `0f73362` (test)

## Files Created/Modified
- `src/lib/services/asset-service.ts` - AssetService: assignToSubscriber, assignToTechnician, returnAsset, disposeAsset, getAssetHistory, getCurrentLocation
- `src/app/api/inventory/items/[id]/assign/route.ts` - POST assign (SUBSCRIBER or TECHNICIAN)
- `src/app/api/inventory/items/[id]/return/route.ts` - POST return with condition
- `src/app/api/inventory/items/[id]/dispose/route.ts` - POST dispose (admin only, 403 for non-admin)
- `src/app/api/inventory/items/[id]/history/route.ts` - GET chronological timeline
- `src/lib/__tests__/asset-service.test.ts` - 11 integration tests

## Decisions Made
- AssetService delegates all movement recording to InventoryService.recordMovement — no direct StockMovement writes
- Disposal JE created separately before movement record — InventoryService only auto-creates JEs for RECEIVED movements
- getCurrentLocation derives from latest movement's toLocationType/toLocationId (null for DISPOSED)
- returnAsset always returns to "main-warehouse" — single warehouse model sufficient for ISP scale
- History name resolution uses batch queries then Map lookup — avoids N+1 query pattern

## Deviations from Plan

None - plan executed exactly as written.

## Issues Encountered
None.

## User Setup Required
None - no external service configuration required.

## Next Phase Readiness
- Phase 4 now complete (all 5 plans: 04-01 Inventory, 04-02 Asset Management, 04-03 Expenses, 04-05 Financial Reports)
- Ready for Phase 5

---
*Phase: 04-inventory-expenses-and-financial-reports*
*Completed: 2026-03-05*