# UpdateOutboundShipment

## Permission Scope

outboundShipmentOperation

## Overview

updateOutboundShipment updates a DRAFT OutboundShipment via `headerPatch` and revises its OutboundShipmentLine set via `addLines`, `updateLines`, and `removeLineIds`.

## Business Rules

- The target OutboundShipment must exist and be in DRAFT status
- Posted outbound shipments cannot be updated
- effectiveDate can be updated independently
- `updateLines` and `removeLineIds` must target a line that exists on the shipment
- `updateLines` patches the existing line in place, so its id and createdAt are preserved
- At least one line must remain after the changes
- Added and updated lines follow the same validation rules as createOutboundShipment
- Added and updated lines must provide both source-unit quantity/unitId and converted primaryQuantity/unitConversionRate snapshots
- Added and updated line primaryUnitId must equal Item.unitId
- Added line source references are required and must use SALES_ORDER
- Outbound valuation derives cost from the active inventory valuation policy during posting; unit cost is not accepted as command input
- No stock or ledger changes occur during update

## Process Flow

```mermaid
flowchart TD
    A[Update outbound shipment request] --> B[Lock OutboundShipment]
    B --> C{DRAFT?}
    C -->|No| D[Return error: INVALID_STATUS]
    C -->|Yes| E{Target lines exist?}
    E -->|No| F[Return error: SHIPMENT_LINE_NOT_FOUND]
    E -->|Yes| H{At least one line remains?}
    H -->|No| I[Return error: EMPTY_SHIPMENT_LINES]
    H -->|Yes| J[Validate added and updated lines]
    J --> K[Apply header updates and line changes]
    K --> M[Return updated shipment id]
```

## External Dependencies

- [item-management::Item](../../../item-management/docs/model/Item.md) - Validates referenced items
- [outbound-shipment::OutboundShipment](../model/OutboundShipment.md) - Updates the shipment header and revises outbound shipment lines

## Error Scenarios

- **INVALID_STATUS**: Target entity is not in a valid status for this operation
- **SHIPMENT_LINE_NOT_FOUND**: Referenced outbound shipment line does not exist on the target shipment
- **EMPTY_SHIPMENT_LINES**: No outbound shipment lines were provided
- **INVALID_QUANTITY**: Quantity is zero or negative
- **PRIMARY_UNIT_MISMATCH**: primaryUnitId differs from Item.unitId
- **INVALID_UNIT_CONVERSION_RATE**: Unit conversion rate is zero or negative
- **ITEM_NOT_FOUND**: Referenced item does not exist
- **STORAGE_LOCATION_NOT_FOUND**: Referenced storage location does not exist

## Test Cases

- updates header metadata on a draft outbound shipment
- updates a line in place so its id survives the edit
- updates the source references on an existing line
- adds an outbound shipment line via addLines
- removes an outbound shipment line via removeLineIds
- returns error when the outbound shipment does not exist
- returns error when outbound shipment is not draft
- returns error when an update targets a missing line
- returns error when a removal would leave the shipment without lines
- returns error when an added line primary quantity is zero or negative
- returns error when an added line unit conversion rate is zero or negative
- returns error when an added line primary unit differs from item primary unit
- revalidates the item when only the primary unit changes on an existing line