DP44/enriched-qwen3-coder-next/Common/DTS.CommonCore/Interface/SystemSettings/ISOSettings.md

---
source_files:
  - Common/DTS.CommonCore/Interface/SystemSettings/ISOSettings/IisoSettingsView.cs
  - Common/DTS.CommonCore/Interface/SystemSettings/ISOSettings/IISOSettingsModel.cs
  - Common/DTS.CommonCore/Interface/SystemSettings/ISOSettings/IISOSettingsViewModel.cs
  - Common/DTS.CommonCore/Interface/SystemSettings/ISOSettings/IISOSettingsData.cs
generated_at: "2026-04-16T02:31:37.120937+00:00"
model: "Qwen/Qwen3-Coder-Next-FP8"
schema_version: 1
sha256: "7b8cfe6060429ed5"
---

# ISOSettings

## Documentation Page: ISO Settings Module

### 1. Purpose  
This module defines the core interfaces for managing ISO (International Organization for Standardization) code settings within the system’s settings infrastructure. It implements a standard Model-View-ViewModel (MVVM) pattern to decouple configuration data (`IISOSettingsData`), business logic/data persistence (`IISOSettingsModel`), and UI presentation (`IISOSettingsView` and `IISOSettingsViewModel`). Its role is to provide a structured, testable abstraction layer for storing, loading, and exposing user-configurable ISO-related display and validation preferences—such as whether ISO codes must be unique, which view modes are active, and which helper UI elements (e.g., code builder, channel lookup) are visible.

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### 2. Public Interface  

#### `IISOSettingsView`  
- **Signature**: `interface IISOSettingsView : IBaseView`  
- **Behavior**: Represents the view layer contract for ISO settings UI. Inherits from `IBaseView`, implying standard view lifecycle/interaction capabilities (e.g., data binding, initialization hooks). No additional members defined—implementation responsibility lies in concrete view classes.

#### `IISOSettingsModel`  
- **Signature**: `interface IISOSettingsModel : IBaseModel`  
- **Behavior**: Manages persistence of ISO settings.  
  - `void SaveData(IISOSettingsData data)`: Persists the provided `IISOSettingsData` instance.  
  - `IISOSettingsData LoadData()`: Retrieves and returns the current persisted ISO settings data.  
  Inherits from `IBaseModel`, implying standard model responsibilities (e.g., state management, validation hooks).

#### `IISOSettingsViewModel`  
- **Signature**: `interface IISOSettingsViewModel : IBaseViewModel`  
- **Behavior**: Orchestrates interaction between view, model, and data.  
  - `IISOSettingsView View { get; set; }`: Gets or sets the associated view instance.  
  - `IISOSettingsData ISOData { get; set; }`: Gets or sets the current ISO settings data model.  
  - `IISOSettingsModel Model { get; set; }`: Gets or sets the associated data persistence model.  
  Inherits from `IBaseViewModel`, implying standard MVVM behaviors (e.g., command binding, property change notification).

#### `IISOSettingsData`  
- **Signature**: `interface IISOSettingsData : IBaseClass`  
- **Behavior**: Encapsulates configurable ISO settings properties.  
  - `bool UniqueISOCodesRequired { get; set; }`: Controls whether duplicate ISO codes are disallowed.  
  - `IsoViewMode ISOViewMode { get; set; }`: Sets the current display mode for ISO codes (enum value from `DTS.Common.Enums`).  
  - `bool ShowISOStringBuilder { get; set; }`: Toggles visibility of the ISO code builder UI helper.  
  - `bool ShowChannelCodeLookupHelper { get; set; }`: Toggles visibility of the channel code lookup helper.  
  - `bool UseISOCodeFilterMapping { get; set; }`: Enables/disables filtering logic based on ISO code mappings.  
  - `bool ShowISOCodes { get; }`: *Read-only* flag indicating whether ISO codes should be displayed.  
  - `bool ShowUserCodes { get; }`: *Read-only* flag indicating whether user-defined codes should be displayed.  
  - `bool ChannelNamesOnly { get; }`: *Read-only* flag indicating whether only channel names (not codes) should be shown.  
  Inherits from `IBaseClass`, implying base functionality (e.g., equality, cloning—exact behavior depends on `IBaseClass` implementation).

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### 3. Invariants  
- **Data Integrity**: `SaveData` and `LoadData` must ensure data consistency—`LoadData()` should return a valid `IISOSettingsData` instance (non-null) representing the persisted state.  
- **Read-Only Properties**: `ShowISOCodes`, `ShowUserCodes`, and `ChannelNamesOnly` are read-only; their values must be determined internally (e.g., derived from `ISOViewMode` or other settings) and not settable directly.  
- **MVVM Coupling**: `IISOSettingsViewModel` requires all three dependencies (`View`, `Model`, `ISOData`) to be non-null for correct operation (enforced by implementation, not interface).  
- **Enum Dependency**: `ISOViewMode` is defined in `DTS.Common.Enums`; its valid values and semantics must be consistent with the behavior of `ShowISOCodes`, `ShowUserCodes`, and `ChannelNamesOnly`.

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### 4. Dependencies  

#### Dependencies *of* this module:  
- `DTS.Common.Base`: Provides base contracts (`IBaseView`, `IBaseModel`, `IBaseViewModel`, `IBaseClass`).  
- `DTS.Common.Enums`: Defines the `IsoViewMode` enum used in `IISOSettingsData`.  

#### Dependencies *on* this module:  
- Any module implementing or consuming ISO settings (e.g., UI components, persistence layers, configuration services) must depend on these interfaces.  
- Concrete implementations of `IISOSettingsView`, `IISOSettingsModel`, `IISOSettingsViewModel`, and `IISOSettingsData` are expected elsewhere in the codebase (not specified here).  

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### 5. Gotchas  
- **Read-Only Properties**: `ShowISOCodes`, `ShowUserCodes`, and `ChannelNamesOnly` are read-only but may be computed from `ISOViewMode` or other settings. Modifying `ISOViewMode` could indirectly change these values.  
- **No Validation Logic**: The interfaces define *what* data is stored and how it’s persisted but contain no validation rules (e.g., `UniqueISOCodesRequired` is a flag, but enforcement logic must reside in implementation).  
- **Null Safety**: The `ViewModel` interface allows setting `View`, `Model`, or `ISOData` to `null`; implementations must handle null references gracefully (e.g., via guards or default instances).  
- **No Explicit Error Handling**: `SaveData`/`LoadData` signatures do not declare exceptions—implementation may throw (e.g., on I/O failure), but callers must infer error paths.  
- **Namespace Overlap**: All interfaces reside in `DTS.Common.Interface`, suggesting this is part of a shared core library; changes may impact multiple consumers.  

None identified beyond the above.