CardsTools

A console deck manager — DI Host, Command pattern, real Memento undo/redo

Русская версия

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A small interactive console application that lets you build, edit, persist and replay decks of playing- or divination-cards. The project started as a sandbox for OOP and grew into a portfolio piece showing how the same domain can be expressed cleanly with DI, Command pattern, Memento and source-generated APIs.

What is showcased

• Generic Host + DI — Host.CreateApplicationBuilder with everything resolved through the container; no Singleton patterns anywhere.
• IHostedService drives the console loop with cooperative shutdown on Ctrl-C.
• Declarative menu DSL — MenuBuilder.Root(...) fluently composes the menu tree on top of the existing IMenu/IMenuItem framework.
• Command pattern — every destructive operation (AddCardCommand, RemoveCardCommand, SortByPowerCommand, …) implements IDeckCommand and goes through a CommandRunner that snapshots a memento before applying.
• Real Undo/Redo via Memento — DeckHistory (two-stack) lets users walk forward and back through their edits; failed commands roll their memento back automatically.
• System.Text.Json source-generated persistence — no reflection at runtime, AOT-friendly serialisation via [JsonSerializable] + JsonSerializerContext.
• [LoggerMessage] source generator for allocation-free structured logs.
• Sealed records (Card, CardsMemento, DeckSnapshot) for invariant-preserving immutable data.
• xUnit + FluentAssertions test suite (21 tests covering deck invariants, history, command runner, manager and menu builder).

Project layout

CardsTools/
├── Program.cs                       Host.CreateApplicationBuilder composition root
├── Hosting/
│   └── ConsoleAppService.cs         BackgroundService driving the console UI
├── Menu/
│   └── MenuBuilder.cs               Fluent DSL on top of the menu framework
├── Commands/
│   ├── IDeckCommand.cs              Command pattern interface + base class
│   ├── DeckCommands.cs              AddCard / RemoveCard / Clear / Sort / Shuffle
│   └── CommandRunner.cs             Saves memento → applies command → rolls back on failure
├── Persistence/
│   ├── IDeckStorage.cs              Save / Load / ListSaved abstraction
│   ├── JsonDeckStorage.cs           Filesystem impl + timestamped backups
│   └── JsonContext.cs               System.Text.Json source-generated context
├── Data/
│   ├── Models/
│   │   ├── Card.cs                  sealed record Card(Id, Name, Description, Power)
│   │   └── DeckOfCards.cs           Domain model + OperationResult struct
│   ├── Managers/
│   │   ├── CardManager.cs           DI-managed; owns decks + per-deck histories
│   │   └── MenuManager/             Hand-rolled console menu framework
│   │       ├── IMenu.cs, IMenuItem.cs, Menu.cs, MenuItem.cs
│   │       ├── Binding.cs           Keyboard → MenuPoint switch expression
│   │       └── MenuPoint.cs, ArgumentActionExecutionEvent.cs
│   └── Tools/
│       ├── CardsMemento.cs          Immutable snapshot record
│       ├── CardCollectionHistory.cs DeckHistory: two-stack Undo/Redo
│       └── ValidationCard.cs        Tiny input helpers
└── tests/
    └── CardsTools.Tests/            xUnit + FluentAssertions

Quick start

dotnet restore
dotnet run

Use ↑/↓ to navigate, Enter to select, Esc to go back, Ctrl+C to quit. Decks are persisted under DeckCardSave/ with timestamped backups under DeckCardSave/Backup/<deck>/.

Development

dotnet format --verify-no-changes        # check style
dotnet build --configuration Release     # build
dotnet test                              # 21 xUnit tests

Tech stack

Layer	Library
Runtime	.NET 10
Hosting / DI	Microsoft.Extensions.Hosting
Logging	Serilog + [LoggerMessage] generators
JSON	System.Text.Json (source-generated context, AOT-friendly)
Tests	xUnit + FluentAssertions

License

MIT.