using Domain;
using System.Reflection;

namespace Db.Tests;

/// <summary>The domain stayed clean: Client/Order do NOT derive from <see cref="DbBase"/> and expose no <see cref="DbContext"/>-typed member; asserted from the persistence side, where both are visible.</summary>
public class DomainStaysPlainTests
{
    private const BindingFlags AllMembers =
        BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance | BindingFlags.Static;

    // The leak is gone: no DbBase in the base chain, no DbContext-typed member (reflection).
    [Theory]
    [InlineData(typeof(Client))]
    [InlineData(typeof(Order))]
    public void Domain_objects_are_plain__no_DbBase_no_DbContext_member(Type type)
    {
        // Not DbBase, and not a derived type either (walk the base chain):
        for (var t = type; t is not null && t != typeof(object); t = t.BaseType)
            Assert.NotSame(typeof(DbBase), t);

        // No DbContext-typed member, public or private:
        foreach (var p in type.GetProperties(AllMembers))
            Assert.True(p.PropertyType != typeof(DbContext),
                $"{type.Name}.{p.Name} leaks a DbContext-typed property");
        foreach (var f in type.GetFields(AllMembers))
            Assert.True(f.FieldType != typeof(DbContext),
                $"{type.Name}.{f.Name} leaks a DbContext-typed field");
    }
}