maraphon-app/plans/initial-implementation/phase-1-solution-and-domain.md

Phase 1: Solution Skeleton + Domain Model

Status: ⬜ Not Started Parent plan: PLAN.md Domain: backend

Objective

Create the .NET 8 solution structure (5 source projects + 4 test projects) and implement the core domain model — entities, value objects, enums, and invariants — with no external dependencies. This establishes the foundation that all later phases reference.

Tasks

• Create Marathon.sln with these projects:
  • src/Marathon.Domain/Marathon.Domain.csproj (classlib, .NET 8, no deps)
  • src/Marathon.Application/Marathon.Application.csproj (classlib, refs Domain)
  • src/Marathon.Infrastructure/Marathon.Infrastructure.csproj (classlib, refs Domain + Application)
  • src/Marathon.UI/Marathon.UI.csproj (Razor Class Library, refs Domain + Application)
  • src/Marathon.Hosts.WpfBlazor/Marathon.Hosts.WpfBlazor.csproj (WPF + BlazorWebView, refs Marathon.UI + Marathon.Infrastructure + Marathon.Application)
  • tests/Marathon.Domain.Tests/Marathon.Domain.Tests.csproj (xUnit)
  • tests/Marathon.Application.Tests/Marathon.Application.Tests.csproj (xUnit)
  • tests/Marathon.Infrastructure.Tests/Marathon.Infrastructure.Tests.csproj (xUnit)
  • tests/Marathon.UI.Tests/Marathon.UI.Tests.csproj (bUnit + xUnit)
• Add Directory.Build.props at repo root with shared settings:

  <Project>
    <PropertyGroup>
      <TargetFramework>net8.0</TargetFramework>
      <Nullable>enable</Nullable>
      <ImplicitUsings>enable</ImplicitUsings>
      <LangVersion>12</LangVersion>
      <TreatWarningsAsErrors Condition="'$(Configuration)'=='Release'">true</TreatWarningsAsErrors>
      <AnalysisLevel>latest</AnalysisLevel>
    </PropertyGroup>
  </Project>
  

• Add Directory.Packages.props for centralized NuGet versions (mark <ManagePackageVersionsCentrally>true</ManagePackageVersionsCentrally>).
• Add .editorconfig at repo root with C# formatting rules consistent with CLAUDE.md conventions (file-scoped namespaces, 4-space indent, etc.).
• Implement Marathon.Domain types:
  • Value objects (records):
    • SportCode(int Value) — must be > 0
    • EventId(string Value) — bookmaker's event identifier (string, not int)
    • Side enum: Side1, Side2, Draw, Less, More
    • BetScope discriminated union: Match | Period(int Number) (use record hierarchy)
    • BetType enum: Win, Draw, WinFora, Total
    • OddsRate(decimal Value) — must be > 1.0
    • OddsValue(decimal Value) — handicap or total threshold (e.g., -5.5, 220.5)
  • Entities (use records or classes with private setters as appropriate):
    • Sport(SportCode Code, string NameRu, string NameEn)
    • Country(string Code, string NameRu, string NameEn)
    • League(string Id, SportCode Sport, string Country, string NameRu, string NameEn, string Category)
    • Event(EventId Id, SportCode Sport, string CountryCode, string LeagueId, string Category, DateTimeOffset ScheduledAt, string Side1Name, string Side2Name)
    • Bet(BetScope Scope, BetType Type, Side Side, OddsValue? Value, OddsRate Rate)
    • OddsSnapshot(EventId EventId, DateTimeOffset CapturedAt, OddsSource Source, IReadOnlyList<Bet> Bets) where OddsSource = PreMatch | Live
    • EventResult(EventId EventId, int Side1Score, int Side2Score, Side WinnerSide, DateTimeOffset CompletedAt)
    • Anomaly(Guid Id, EventId EventId, DateTimeOffset DetectedAt, AnomalyKind Kind, decimal Score, string EvidenceJson) where AnomalyKind = SuspensionFlip
• Implement domain invariants in record constructors / static factory methods.
• Implement Marathon.Domain.Tests — TDD tests for invariants:
  • OddsRate rejects ≤ 1.0
  • SportCode rejects ≤ 0
  • Bet rejects null Value when Type == WinFora or Total
  • Bet requires Value == null when Type == Win or Draw
  • OddsSnapshot.Bets is non-empty
  • Event.ScheduledAt is UTC (Offset == TimeSpan.Zero)
  • Domain types are immutable (no settable public properties)

Files to Modify/Create

• Marathon.sln
• Directory.Build.props
• Directory.Packages.props
• .editorconfig
• src/Marathon.Domain/** — entities, VOs, enums, invariants
• src/Marathon.Application/Marathon.Application.csproj — empty stub csproj
• src/Marathon.Infrastructure/Marathon.Infrastructure.csproj — empty stub
• src/Marathon.UI/Marathon.UI.csproj — empty RCL stub
• src/Marathon.Hosts.WpfBlazor/Marathon.Hosts.WpfBlazor.csproj — empty stub
• tests/Marathon.Domain.Tests/** — invariant tests
• tests/Marathon.{Application,Infrastructure,UI}.Tests/*.csproj — empty xUnit stubs

Acceptance Criteria

• dotnet build Marathon.sln succeeds (compile-only smoke check, allowed in Big Bang).
• All domain tests pass (dotnet test tests/Marathon.Domain.Tests is allowed even in Big Bang since this is the foundation phase and the test project is self-contained).
• Domain types are public, immutable records with invariants enforced in constructors.
• No EF Core, scraping, or UI code in this phase.

Notes

• Use file-scoped namespaces and one type per file (except small enum + record groups).
• Domain types must NOT reference System.Net.Http, EF Core, or any infrastructure.
• For the discriminated union BetScope, use a record hierarchy:

  public abstract record BetScope { /* private ctor */ }
  public sealed record MatchScope : BetScope;
  public sealed record PeriodScope(int Number) : BetScope;
  

  Or a single record with a nullable PeriodNumber — implementer's choice, document it.
• Test framework: xUnit with FluentAssertions. Don't add Mockito/NSubstitute yet (no abstractions to mock in Domain).

Review Checklist

• Solution builds (dotnet build)
• Domain tests all pass
• No external deps in Marathon.Domain.csproj except framework packages
• Public API surface is minimal — only what later phases need
• All types follow CLAUDE.md naming/style conventions

Handoff to Next Phase