# Module: Azaion.Common.Entities.User

## Purpose
Domain entity representing a system user, plus related value objects `UserConfig` and `UserQueueOffsets`.

## Public Interface

### User
| Property | Type | Description |
|----------|------|-------------|
| `Id` | `Guid` | Primary key |
| `Email` | `string` | Unique user email |
| `PasswordHash` | `string` | SHA-384 hash of plaintext password |
| `Hardware` | `string?` | Raw hardware fingerprint string (set on first resource access) |
| `Role` | `RoleEnum` | Authorization role |
| `CreatedAt` | `DateTime` | Account creation timestamp |
| `LastLogin` | `DateTime?` | Last successful resource-check/hardware-check timestamp |
| `UserConfig` | `UserConfig?` | JSON-serialized user configuration |
| `IsEnabled` | `bool` | Account active flag |

| Method | Signature | Description |
|--------|-----------|-------------|
| `GetCacheKey` | `static string GetCacheKey(string email)` | Returns cache key `"User.{email}"` |

### UserConfig
| Property | Type | Description |
|----------|------|-------------|
| `QueueOffsets` | `UserQueueOffsets?` | Annotation queue offset tracking |

### UserQueueOffsets
| Property | Type | Description |
|----------|------|-------------|
| `AnnotationsOffset` | `ulong` | Offset for annotations queue |
| `AnnotationsConfirmOffset` | `ulong` | Offset for annotation confirmations |
| `AnnotationsCommandsOffset` | `ulong` | Offset for annotation commands |

## Internal Logic
`GetCacheKey` returns empty string for null/empty email to avoid cache key collisions.

## Dependencies
- `RoleEnum`

## Consumers
- All services (`UserService`, `AuthService`, `ResourcesService`) work with `User`
- `AzaionDb` exposes `ITable<User>`
- `AzaionDbSchemaHolder` maps `User` to the `users` PostgreSQL table
- `SetUserQueueOffsetsRequest` uses `UserQueueOffsets`

## Data Models
Maps to PostgreSQL table `users` with columns: `id`, `email`, `password_hash`, `hardware`, `role`, `user_config` (JSON text), `created_at`, `last_login`, `is_enabled`.

## Configuration
None.

## External Integrations
None.

## Security
`PasswordHash` stores SHA-384 hash. `Hardware` stores raw hardware fingerprint (hashed for comparison via `Security.GetHWHash`).

## Tests
Indirectly tested via `UserServiceTest` and `SecurityTest`.