A modern, full-featured Sudoku game built with Blazor Server and C#, following Clean Architecture and Domain-Driven Design (DDD) principles. The solution is modular, testable, and cloud-ready, featuring a clean interactive UI, multiple difficulty levels, and robust backend logic.

This solution is organized into several projects:

Sudoku.sln
├── Sudoku.Domain/           # Core domain logic and business rules
├── Sudoku.Application/      # Application use cases and orchestration
├── Sudoku.Infrastructure/   # Infrastructure (storage, external APIs)
├── Sudoku.Web.Server/       # Blazor Server web UI
├── Sudoku.Api/              # REST API (optional)
├── Sudoku.Storage.Azure/    # Azure storage implementation
├── Sudoku.AppHost/          # Application orchestration/hosting
└── Tests/                   # Unit and integration tests

• .NET 9.0 throughout
• Blazor Server for real-time, interactive UI
• Domain-Driven Design (DDD): Rich domain models, value objects, domain events
• Clean Architecture: Clear separation of concerns between domain, application, infrastructure, and UI
• CQRS Pattern: Commands and queries are handled separately for scalability and maintainability
• Azure Storage: Cloud persistence for game state
• Dependency Injection: For all services and repositories
• Comprehensive Testing: Unit and integration tests for all layers

1. User Interaction: Browser → Blazor Server → SignalR Hub
2. Game Logic: Web Services → Domain Layer
3. State Management: Game state stored in memory, local storage, or Azure
4. Persistence: Azure Blob Storage with optional caching

• Multiple difficulty levels (Easy, Medium, Hard)
• Real-time, interactive UI
• Game state persistence (local and cloud)
• Undo/redo, pencil mode, and validation
• Modular, extensible architecture

Prerequisites:

• .NET 9.0 SDK
• (Optional) Azure account for cloud storage features

To build the solution:

dotnet build

To run the Blazor Server app locally:

dotnet run --project Sudoku.Web.Server

The app will be available at https://localhost:5001 (or as indicated in the console output).

To run all tests:

dotnet test

For a detailed architecture diagram and explanation, see current-architecture-diagram.md in the root of the repository.