# Domain Models Specification - Change Delta

This document captures modifications to the base `domain-models` specification for the `implement-domain-models` change.

## Base Specification

Reference: `openspec/specs/domain-models/spec.md`

## ADDED Requirements

### Requirement: JdeDateConverter helper class
The system SHALL provide a static helper class for converting JDE date/time formats to .NET DateTime.

#### Methods

| Method | Signature | Description |
|--------|-----------|-------------|
| ToDateTime | `DateTime? ToDateTime(int jdeDate, int jdeTime = 0)` | Converts JDE CYYDDD date and HHMMSS time to DateTime |

#### Business Rules

- Returns `null` for zero or invalid date values (not `1900-01-01`)
- CYYDDD format: C = century (0=1900s, 1=2000s), YY = year, DDD = day of year
- HHMMSS format: HH = hours (0-23), MM = minutes (0-59), SS = seconds (0-59)
- Invalid time values are ignored (date portion still returned)
- Parse errors return `null` rather than throwing exceptions

#### Scenario: Convert valid JDE date
- **WHEN** JdeDateConverter.ToDateTime(124365, 143052) is called
- **THEN** returns DateTime 2024-12-30 14:30:52

#### Scenario: Handle zero date
- **WHEN** JdeDateConverter.ToDateTime(0, 0) is called
- **THEN** returns null

#### Scenario: Handle invalid day of year
- **WHEN** JdeDateConverter.ToDateTime(124400, 0) is called (day 400 is invalid)
- **THEN** returns null

---

### Requirement: Extension method file organization
The system SHALL organize ToViewModel extension methods in separate files by entity type.

#### File Structure

| File | Extension Methods |
|------|-------------------|
| WorkOrderExtensions.cs | WorkOrder.ToViewModel() |
| LotExtensions.cs | Lot.ToViewModel() |
| ItemExtensions.cs | Item.ToViewModel() |
| WorkCenterExtensions.cs | WorkCenter.ToViewModel() |
| ProfitCenterExtensions.cs | ProfitCenter.ToViewModel() |
| JdeUserExtensions.cs | JdeUser.ToViewModel() |

#### Business Rules

- Extension methods in `JdeScoping.Core.Extensions` namespace
- Each file contains a single static class with extension methods for one entity type
- Extension methods are the only way entities project to ViewModels (no methods on entities)

#### Scenario: Use extension method for projection
- **WHEN** a WorkOrder entity calls ToViewModel() extension method
- **THEN** a WorkOrderViewModel is returned with WorkOrderNumber and ItemNumber

---

### Requirement: ViewModel file organization
The system SHALL organize ViewModel classes in a dedicated ViewModels folder.

#### File Structure

| File | ViewModel Class |
|------|-----------------|
| WorkOrderViewModel.cs | WorkOrderViewModel record |
| LotViewModel.cs | LotViewModel record |
| ItemViewModel.cs | ItemViewModel record |
| WorkCenterViewModel.cs | WorkCenterViewModel record |
| ProfitCenterViewModel.cs | ProfitCenterViewModel record |
| JdeUserViewModel.cs | JdeUserViewModel record |
| PartOperationViewModel.cs | PartOperationViewModel record |

#### Business Rules

- ViewModels in `JdeScoping.Core.ViewModels` namespace
- ViewModels are immutable DTOs (prefer `record` type)
- ViewModels contain only serializable properties (no computed properties)

#### Scenario: ViewModel serialization
- **WHEN** a WorkOrderViewModel is serialized to JSON
- **THEN** all properties are included in the output

---

### Requirement: Enum file organization
The system SHALL organize enum types in a dedicated Enums folder.

#### File Structure

| File | Enum Type |
|------|-----------|
| SearchStatus.cs | SearchStatus enum |
| UpdateTypes.cs | UpdateTypes enum |

#### Business Rules

- Enums in `JdeScoping.Core.Models.Enums` namespace
- All enums that may be serialized MUST have `[JsonConverter(typeof(JsonStringEnumConverter))]`

#### Scenario: Enum JSON serialization
- **WHEN** SearchStatus.Ended is serialized to JSON
- **THEN** the output is "Ended" (string), not 3 (integer)

---

## MODIFIED Requirements

### Requirement: Search entity
The system SHALL store user search requests containing filter criteria and resulting Excel output, with lazy deserialization of criteria from JSON.

#### Properties

| Property | Type | Description |
|----------|------|-------------|
| ID | int | Primary key identifier |
| UserName | string | Username of user who created search |
| Name | string | User-friendly name for the search |
| Status | SearchStatus | Current search status (enum) |
| SubmitDT | DateTime? | Timestamp when search was submitted |
| StartDT | DateTime? | Timestamp when search processing started |
| EndDT | DateTime? | Timestamp when search completed |
| CriteriaJSON | string | JSON-serialized search criteria |
| Criteria | SearchCriteria | Deserialized search criteria object |
| Results | byte[]? | Excel file output (VARBINARY), nullable when not yet generated |

#### Business Rules

- Status MUST be serialized as string using `[JsonConverter(typeof(JsonStringEnumConverter))]`
- Criteria is stored as JSON in `CriteriaJSON` for database persistence
- `Criteria` property getter deserializes from `CriteriaJSON` using System.Text.Json
- Setter serializes to `CriteriaJSON`
- If `CriteriaJSON` is null or empty, `Criteria` returns a new empty `SearchCriteria`
- Deserialization errors return empty `SearchCriteria` (fail gracefully)
- Results contains binary Excel file data only when Status = Ended
- Results property MUST be annotated as `byte[]?` since it is null until processing completes

#### Scenario: Lazy deserialization of Criteria
- **WHEN** Search.CriteriaJSON = '{"MinimumDT":"2024-01-01"}' and Criteria is accessed
- **THEN** Criteria.MinimumDT = 2024-01-01

#### Scenario: Handle empty CriteriaJSON
- **WHEN** Search.CriteriaJSON = null and Criteria is accessed
- **THEN** Criteria returns new SearchCriteria() with all empty lists

---

### Requirement: SearchUpdate entity
The system SHALL provide a real-time status update message for ASP.NET Core SignalR broadcast with factory method construction.

#### Properties

| Property | Type | Description |
|----------|------|-------------|
| ID | int | Search primary key |
| UserName | string | Username of search submitter |
| Name | string | Search name |
| Status | SearchStatus | Current status |
| SubmitDT | DateTime? | Submit timestamp |
| StartDT | DateTime? | Start timestamp |
| EndDT | DateTime? | End timestamp |
| Timestamp | DateTime | When update was generated |
| HasResults | bool | Indicates if search has Results |

#### Business Rules

- Primary constructor: `SearchUpdate(Search search)` copies all fields and sets Timestamp
- Timestamp MUST be set to `DateTime.UtcNow` when update is created
- Status MUST be serialized as string for JSON via `[JsonConverter(typeof(JsonStringEnumConverter))]`
- `HasResults` is computed: `Status == SearchStatus.Ended && search.Results != null`

#### Scenario: Create SearchUpdate from Search
- **WHEN** SearchUpdate is created from a Search with ID=1, Status=Ended
- **THEN** SearchUpdate.ID = 1, SearchUpdate.Status = Ended, SearchUpdate.Timestamp = current UTC time

#### Scenario: HasResults computation
- **WHEN** SearchUpdate is created from Search with Status=Ended and Results is not null
- **THEN** HasResults = true

---

### Requirement: UserInfo entity
The system SHALL provide authenticated user information with computed display name for ASP.NET Core Identity integration.

#### Properties

| Property | Type | Description |
|----------|------|-------------|
| Username | string | User's login identifier |
| FirstName | string? | User's first name (nullable) |
| LastName | string? | User's last name (nullable) |
| DisplayName | string | Computed display name |
| Title | string? | Organization title (nullable) |
| EmailAddress | string? | Email address (nullable) |

#### Business Rules

- DisplayName computation:
  1. If FirstName and LastName both have values: `$"{FirstName} {LastName}".Trim()`
  2. If only FirstName has value: `FirstName.Trim()`
  3. If only LastName has value: `LastName.Trim()`
  4. Otherwise: `Username`
- "Has value" means not null and not whitespace-only
- Used for authentication context, populated from ASP.NET Core Identity claims or LDAP provider
- DN (Distinguished Name) property removed; use ClaimsPrincipal for identity information

#### Scenario: Compute display name from both names
- **WHEN** UserInfo has FirstName = "John", LastName = "Doe" and DisplayName is accessed
- **THEN** DisplayName = "John Doe"

#### Scenario: Compute display name from first name only
- **WHEN** UserInfo has FirstName = "John", LastName = null and DisplayName is accessed
- **THEN** DisplayName = "John"

#### Scenario: Fallback to username when names empty
- **WHEN** UserInfo has FirstName = null, LastName = null, Username = "jdoe" and DisplayName is accessed
- **THEN** DisplayName = "jdoe"

---

## CLARIFICATIONS

### Private JDE Date Fields

Entities with JDE date fields use this pattern:

```csharp
public class SomeEntity
{
    // These are mapped by Dapper from database columns
    // but not exposed publicly
    private int LastUpdateDate { get; set; }
    private int LastUpdateTime { get; set; }

    // Public computed property
    public DateTime? LastUpdateDT => JdeDateConverter.ToDateTime(LastUpdateDate, LastUpdateTime);
}
```

The private setters allow Dapper to populate the values during query mapping, while the computed property provides the converted DateTime.

### Collection Initialization

All collection properties use C# 12 collection expression syntax:

```csharp
public List<string> Items { get; set; } = [];
```

This ensures collections are never null and always initialized to empty.

### Namespace Organization

| Folder | Namespace |
|--------|-----------|
| Models/ | JdeScoping.Core.Models |
| Models/Enums/ | JdeScoping.Core.Models.Enums |
| ViewModels/ | JdeScoping.Core.ViewModels |
| Extensions/ | JdeScoping.Core.Extensions |
| Interfaces/ | JdeScoping.Core.Interfaces |
| Helpers/ | JdeScoping.Core.Helpers |