PkmnLib.NET/Plugins/PkmnLib.Plugin.Gen7.Tests/Scripts/Moves/ChargeTests.cs

using PkmnLib.Dynamic.Models;
using PkmnLib.Dynamic.ScriptHandling;
using PkmnLib.Dynamic.ScriptHandling.Registry;
using PkmnLib.Plugin.Gen7.Scripts.Moves;
using PkmnLib.Plugin.Gen7.Scripts.Pokemon;
using PkmnLib.Static;
using PkmnLib.Static.Moves;

namespace PkmnLib.Plugin.Gen7.Tests.Scripts.Moves;

/// <summary>
/// Tests for the <see cref="Charge"/> move script and the <see cref="ChargeEffect"/> it applies.
/// Gen VII Bulbapedia behavior: Charge doubles the power of the user's next Electric-type move,
/// and "It also raises the user's Special Defense stat by one stage."
/// </summary>
public class ChargeTests
{
    private static (Charge script, IExecutingMove move, IPokemon user, IScriptSet userVolatile) CreateTestSetup()
    {
        var script = new Charge();
        var move = Substitute.For<IExecutingMove>();
        var user = Substitute.For<IPokemon>();
        // Use a real script set so the volatile script added by Charge can be inspected afterwards.
        var userVolatile = new ScriptSet(user);
        user.Volatile.Returns(userVolatile);
        user.GetScripts().Returns(_ => new ScriptIterator(new List<IEnumerable<ScriptContainer>>()));
        move.User.Returns(user);
        return (script, move, user, userVolatile);
    }

    /// <summary>
    /// Creates an executing move of the given type whose damage modifier can be changed by
    /// <see cref="ChargeEffect.ChangeDamageModifier"/>.
    /// </summary>
    private static (IExecutingMove move, IPokemon target) CreateExecutingMoveOfType(string typeName)
    {
        var library = LibraryHelpers.LoadLibrary();
        var battle = Substitute.For<IBattle>();
        battle.Library.Returns(library);
        var battleData = Substitute.For<IPokemonBattleData>();
        battleData.Battle.Returns(battle);
        var target = Substitute.For<IPokemon>();
        target.BattleData.Returns(battleData);

        library.StaticLibrary.Types.TryGetTypeIdentifier(typeName, out var typeIdentifier);
        var useMove = Substitute.For<IMoveData>();
        useMove.MoveType.Returns(typeIdentifier);
        var move = Substitute.For<IExecutingMove>();
        move.UseMove.Returns(useMove);

        return (move, target);
    }

    /// <summary>
    /// Bulbapedia: "It also raises the user's Special Defense stat by one stage."
    /// </summary>
    [Test]
    public async Task OnSecondaryEffect_Used_RaisesUserSpecialDefenseByOneStage()
    {
        // Arrange
        var (script, move, user, _) = CreateTestSetup();

        // Act
        script.OnSecondaryEffect(move, Substitute.For<IPokemon>(), 0);

        // Assert
        var boost = user.ReceivedCalls().SingleOrDefault(c => c.GetMethodInfo().Name == "ChangeStatBoost");
        await Assert.That(boost).IsNotNull();
        await Assert.That((Statistic)boost!.GetArguments()[0]!).IsEqualTo(Statistic.SpecialDefense);
        await Assert.That((sbyte)boost.GetArguments()[1]!).IsEqualTo((sbyte)1);
        await Assert.That((bool)boost.GetArguments()[2]!).IsTrue();
    }

    /// <summary>
    /// Bulbapedia: Charge doubles the power of the user's next Electric-type move. Using Charge attaches
    /// the <see cref="ChargeEffect"/> volatile script to the user.
    /// </summary>
    [Test]
    public async Task OnSecondaryEffect_Used_AddsChargeEffectToUser()
    {
        // Arrange
        var (script, move, _, userVolatile) = CreateTestSetup();

        // Act
        script.OnSecondaryEffect(move, Substitute.For<IPokemon>(), 0);

        // Assert
        await Assert.That(userVolatile.Contains(ScriptUtils.ResolveName<ChargeEffect>())).IsTrue();
    }

    /// <summary>
    /// Bulbapedia: "If the user's next move is Electric-type", its power is doubled.
    /// </summary>
    [Test]
    public async Task ChargeEffect_ElectricMove_DoublesDamageModifier()
    {
        // Arrange
        var effect = new ChargeEffect();
        var (move, target) = CreateExecutingMoveOfType("electric");
        var modifier = 1.0f;

        // Act
        effect.ChangeDamageModifier(move, target, 0, ref modifier);

        // Assert
        await Assert.That(modifier).IsEqualTo(2.0f);
    }

    /// <summary>
    /// Bulbapedia: only Electric-type moves benefit — a non-Electric move is not boosted by Charge.
    /// </summary>
    [Test]
    public async Task ChargeEffect_NonElectricMove_DoesNotChangeDamageModifier()
    {
        // Arrange
        var effect = new ChargeEffect();
        var (move, target) = CreateExecutingMoveOfType("water");
        var modifier = 1.0f;

        // Act
        effect.ChangeDamageModifier(move, target, 0, ref modifier);

        // Assert
        await Assert.That(modifier).IsEqualTo(1.0f);
    }

    /// <summary>
    /// Bulbapedia: Charge boosts the user's *next* Electric-type move — the effect lasts through the end
    /// of the following turn and then wears off. The effect survives the end of the turn Charge was used
    /// on and removes itself at the end of the next turn.
    /// </summary>
    [Test]
    public async Task ChargeEffect_OnEndTurn_RemovesItselfAfterTheNextTurn()
    {
        // Arrange
        var (script, move, user, userVolatile) = CreateTestSetup();
        script.OnSecondaryEffect(move, Substitute.For<IPokemon>(), 0);
        await Assert.That(userVolatile.TryGet<ChargeEffect>(out var effect)).IsTrue();
        var battle = Substitute.For<IBattle>();

        // Act & Assert - end of the turn of use: effect remains
        effect!.OnEndTurn(user, battle);
        await Assert.That(userVolatile.Contains(ScriptUtils.ResolveName<ChargeEffect>())).IsTrue();

        // Act & Assert - end of the following turn: effect is removed
        effect.OnEndTurn(user, battle);
        await Assert.That(userVolatile.Contains(ScriptUtils.ResolveName<ChargeEffect>())).IsFalse();
    }
}