---
source_files:
  - Common/DTS.CommonCore/Interface/Database/IDatabaseCopyView.cs
  - Common/DTS.CommonCore/Interface/Database/IDatabaseSwitchView.cs
  - Common/DTS.CommonCore/Interface/Database/IDatabaseStatusBarView.cs
  - Common/DTS.CommonCore/Interface/Database/IDatabaseSwitchViewModel.cs
  - Common/DTS.CommonCore/Interface/Database/IUserDbRecord.cs
  - Common/DTS.CommonCore/Interface/Database/IDatabaseCopyViewModel.cs
  - Common/DTS.CommonCore/Interface/Database/IDatabaseStatusBarViewModel.cs
generated_at: "2026-04-16T02:17:57.680551+00:00"
model: "Qwen/Qwen3-Coder-Next-FP8"
schema_version: 1
sha256: "142a1b67b74ee9e9"
---

# Database

## Documentation: Database View/ViewModel Interfaces

### 1. Purpose  
This module defines a set of interfaces for database-related UI components in a Model-View-ViewModel (MVVM) architecture. It provides contracts for views and viewmodels that manage database connection status, database switching (local ↔ remote), and database copying operations. These interfaces decouple UI presentation logic from implementation details, enabling modular UI development and testability. The interfaces are part of the `DTS.Common.Interface.Database` namespace and extend base contracts (`IBaseView`, `IBaseViewModel`) to integrate with the broader DTS framework.

---

### 2. Public Interface  

#### **Interfaces (View Contracts)**  
- **`IDatabaseCopyView : IBaseView`**  
  Marker interface for the view associated with `IDatabaseCopyViewModel`. Represents the UI layer for database copy operations.

- **`IDatabaseSwitchView : IBaseView`**  
  Marker interface for the view associated with `IDatabaseSwitchViewModel`. Represents the UI layer for switching between local and remote databases.

- **`IDatabaseStatusBarView : IBaseView`**  
  Marker interface for the view associated with `IDatabaseStatusBarViewModel`. Represents the UI layer for displaying database connection status (e.g., active database name, connection state).

#### **Interfaces (ViewModel Contracts)**  
- **`IDatabaseSwitchViewModel : IBaseViewModel`**  
  Manages state and logic for switching between local and remote databases.  
  - `IDatabaseSwitchView View { get; set; }`  
    Gets/sets the associated view.  
  - `void Unset()`  
    Releases resources (e.g., event handlers, view references).  
  - `bool RemoteIsActive { get; }`  
    Indicates whether the remote database is currently active.  
  - `string DefaultDbName { get; }`  
    Gets the default database name.  
  - `void InitializeDbSettings(string defaultDbName, string dbHost, bool ntlmAuthentication, string dbUser, string dbPassword)`  
    Initializes database connection settings (note: `SetDefaultDbName` is commented out and unused).  
  - `void SwitchRemote()` / `void SwitchLocal()`  
    Initiates switching to the remote or local database, respectively.  
  - `string DbHost { get; }`, `bool NTLMAuthentication { get; }`, `string DbUser { get; }`, `string DbPassword { get; }`  
    Exposes current database connection configuration.

- **`IDatabaseCopyViewModel : IBaseViewModel`**  
  Manages state and logic for copying data from a remote database to a local database.  
  - `IDatabaseCopyView View { get; set; }`  
    Gets/sets the associated view.  
  - `void Unset()`  
    Releases resources.  
  - `void CopyDatabase()`  
    Performs the copy operation (clears local DB, populates from remote). Uses `DTS.Common.Storage` to resolve local/remote locations.  
  - `void InitializeState(DbType dbType, string dbName)`  
    Initializes viewmodel state with database type and name.  
  - `string DbName { get; }`  
    Gets the target database name.  
  - `IStatusAndProgressBarView OverallProgressBarView { get; }`  
    Gets progress view for the overall copy operation.  
  - `IStatusAndProgressBarView CurrentTaskProgressBarView { get; }`  
    Gets progress view for the current subtask.  
  - `DbType DatabaseType { get; }`  
    Gets the type of database being copied.  
  - `bool CopyEnabled { get; }`  
    Indicates whether the copy operation is enabled.  
  - `bool IsCopyVisible { get; set; }`  
    Controls visibility of the copy UI.

- **`IDatabaseStatusBarViewModel : IBaseViewModel`**  
  Manages state and logic for displaying database connection status in the UI.  
  - `IDatabaseStatusBarView View { get; set; }`  
    Gets/sets the associated view.  
  - `void Unset()`  
    Releases resources.  
  - `DbType DatabaseType { get; }`  
    Gets the database type (e.g., local, remote).  
  - `bool RemoteConnected { get; }`  
    Indicates whether the remote database is connected.  
  - `string ServerName { get; }`  
    Gets the server name (not database name).  
  - `void InitializeValues(DbType dbType, string serverName, bool remoteConnected)`  
    Sets initial values for status display.  
  - `string ActiveDbName { get; }`  
    Gets the currently active database name (e.g., local or remote, depending on state).  
  - `Brush BackgroundBrush { get; }`  
    Gets the background color brush for the active database name display.

#### **Data Interface**  
- **`IUserDbRecord`**  
  Represents a user record in the database.  
  - `int ID { get; set; }`  
    Database ID of the user.  
  - `string UserName { get; set; }`  
    Unique username.  
  - `string DisplayName { get; set; }`  
    User-friendly display name.  
  - `string Password { get; set; }`  
    Hashed and salted password (never stored in plaintext).  
  - `short Role { get; set; }`  
    User role (numeric code).  
  - `DateTime LastModified { get; set; }`  
    Timestamp of last modification.  
  - `string LastModifiedBy { get; set; }`  
    Username of the modifier.  
  - `bool LocalOnly { get; set; }`  
    *Deprecated* flag indicating whether the user should be local-only (not synchronized).

---

### 3. Invariants  
- All view interfaces (`IDatabaseCopyView`, `IDatabaseSwitchView`, `IDatabaseStatusBarView`) extend `IBaseView`, implying they are part of a consistent UI abstraction layer.  
- All viewmodel interfaces (`IDatabaseSwitchViewModel`, `IDatabaseCopyViewModel`, `IDatabaseStatusBarViewModel`) extend `IBaseViewModel`, implying they follow the MVVM pattern and require `Unset()` for resource cleanup.  
- `IDatabaseSwitchViewModel` and `IDatabaseCopyViewModel` share overlapping functionality (e.g., clearing and repopulating local DB), but `IDatabaseCopyViewModel` includes progress tracking via `IStatusAndProgressBarView`.  
- `IUserDbRecord.Password` is explicitly documented as *hashed and salted*; implementations must never store plaintext passwords.  
- `IUserDbRecord.LocalOnly` is marked *deprecated*; its usage should be avoided.  
- `IDatabaseStatusBarViewModel.ActiveDbName` dynamically reflects the active database (local/remote) based on `DatabaseType` and `RemoteConnected` state.  

---

### 4. Dependencies  
- **Internal Dependencies**:  
  - `DTS.Common.Base`: All interfaces inherit from `IBaseView` or `IBaseViewModel`.  
  - `DTS.Common.Enums.Database`: `IDatabaseCopyViewModel` and `IDatabaseStatusBarViewModel` use `DbType` (enum not shown; assumed to define database types like `Local`, `Remote`).  
  - `System.Windows.Media`: `IDatabaseStatusBarViewModel` uses `Brush` (WPF-specific), indicating this module targets WPF UI.  
  - `DTS.Common.Storage`: Referenced in `IDatabaseCopyViewModel.CopyDatabase()` documentation as the source for resolving local/remote database locations.  

- **External Dependencies**:  
  - WPF (`System.Windows.Media`) for `Brush` type.  
  - `System` (via `DateTime`, `string`).  

- **Depended Upon**:  
  - Concrete implementations of these interfaces are expected in UI-layer projects (e.g., WPF views/viewmodels).  
  - Likely consumed by UI controllers or services that manage database operations (e.g., a main window or database manager module).  

---

### 5. Gotchas  
- **`SetDefaultDbName` is commented out** in `IDatabaseSwitchViewModel`; the property `DefaultDbName` is read-only, and initialization relies solely on `InitializeDbSettings`.  
- **`LocalOnly` is deprecated** in `IUserDbRecord` but not removed; implementations should ignore this property.  
- **`IDatabaseStatusBarViewModel.BackgroundBrush`** has no documentation on how it is computed (e.g., based on connection state). Its value is implementation-defined.  
- **`CopyDatabase()` assumes pre-existing schema**: Both `IDatabaseSwitchViewModel` and `IDatabaseCopyViewModel` require the local database to have tables and stored procedures already created.  
- **`IStatusAndProgressBarView` is used but not defined here**: Its contract is assumed to be defined elsewhere (likely in `DTS.Common.Base` or a related module).  
- **No async methods**: All operations (`SwitchRemote`, `CopyDatabase`) are synchronous; implementations may need to offload work to background threads to avoid UI blocking.  
- **`DbPassword` is exposed directly**: The `IDatabaseSwitchViewModel` exposes the plaintext password via `DbPassword { get; }`, which may be a security risk if not handled carefully.