PolyTraderSharp/tests/PolyTrader.Tests/DemoModelTests.cs

using PolyTrader.Modules.CopyTrading.Logic;
using Xunit;
using static PolyTrader.Modules.CopyTrading.Logic.DemoModel;

namespace PolyTrader.Tests
{
    /// <summary>
    /// Sicherheitsnetz für den realistischeren Demo-Modus (Phase 4.2): Exit-Slippage + Fees.
    /// </summary>
    public class DemoModelTests
    {
        [Fact]
        public void ExitFillPrice_is_below_signal_by_half_spread()
        {
            Assert.Equal(0.495m, ExitFillPrice(0.50m, 0.005m));
        }

        [Theory]
        [InlineData(0.011, 0.005, 0.01)]  // Clamp Untergrenze
        [InlineData(0.20, 0.30, 0.01)]    // stark negativ -> Untergrenze
        [InlineData(0.90, 0.005, 0.895)]  // normal im Band
        [InlineData(0.999, 0.005, 0.99)]  // Clamp Obergrenze (0.994 -> 0.99)
        public void ExitFillPrice_clamps_to_valid_range(double signal, double half, double expected)
        {
            Assert.Equal((decimal)expected, ExitFillPrice((decimal)signal, (decimal)half));
        }

        [Fact]
        public void CloseWithFees_subtracts_slippage_and_roundtrip_fee()
        {
            // size 100, signal 0.60 -> exit 0.595, exitUsd 59.5
            // fees = 1% von 50 (Entry) + 1% von 59.5 (Exit) = 0.5 + 0.595 = 1.095
            // pnl = 59.5 - 50 - 1.095 = 8.405
            var (exitUsd, pnl, fees) = CloseWithFees(size: 100m, signalPrice: 0.60m, entryAmountUsd: 50m, feeBps: 100, halfSpread: 0.005m);
            Assert.Equal(59.5m, exitUsd);
            Assert.Equal(1.095m, fees);
            Assert.Equal(8.405m, pnl);
        }

        [Fact]
        public void CloseWithFees_zero_fee_only_slippage()
        {
            var (exitUsd, pnl, fees) = CloseWithFees(100m, 0.60m, 50m, feeBps: 0, halfSpread: 0.005m);
            Assert.Equal(0m, fees);
            Assert.Equal(exitUsd - 50m, pnl);
        }
    }
}