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

using PkmnLib.Dynamic.Models;
using PkmnLib.Dynamic.Models.Choices;
using PkmnLib.Dynamic.ScriptHandling;
using PkmnLib.Dynamic.ScriptHandling.Registry;
using PkmnLib.Plugin.Gen7.Scripts.Battle;
using PkmnLib.Plugin.Gen7.Scripts.Moves;
using PkmnLib.Static;
using PkmnLib.Static.Utils;

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

/// <summary>
/// Tests for the <see cref="FairyLock"/> move script and its attached <see cref="FairyLockEffect"/>.
/// Gen VII Bulbapedia behavior: "Fairy Lock prevents all Pokémon (except Ghost types) on the field from
/// switching out or fleeing during their next turn."
/// </summary>
public class FairyLockTests
{
    /// <summary>
    /// Creates a fully mocked test setup where the battle has a real <see cref="ScriptSet"/> as its volatile
    /// script set.
    /// </summary>
    private static (FairyLock script, IExecutingMove move, IBattlePokemon target, IBattle battle, IScriptSet
        battleVolatile) CreateTestSetup()
    {
        var script = new FairyLock();
        var move = Substitute.For<IExecutingMove>();
        var target = Substitute.For<IBattlePokemon>();

        var battle = Substitute.For<IBattle>();
        battle.GetScripts().Returns(_ => new ScriptIterator(Array.Empty<IEnumerable<ScriptContainer>>()));
        IScriptSet battleVolatile = new ScriptSet(battle);
        battle.Volatile.Returns(battleVolatile);

        target.Battle.Returns(battle);

        return (script, move, target, battle, battleVolatile);
    }

    /// <summary>
    /// Creates a mocked Pokémon with the given type names as its <see cref="IBattlePokemon.Types"/>.
    /// </summary>
    private static IBattlePokemon CreatePokemonWithTypes(params string[] types)
    {
        var pokemon = Substitute.For<IBattlePokemon>();
        pokemon.Types.Returns(types.Select((name, index) => new TypeIdentifier((byte)(index + 1), new StringKey(name)))
            .ToList());
        return pokemon;
    }

    /// <summary>
    /// Bulbapedia: "Fairy Lock prevents all Pokémon (except Ghost types) on the field from switching out or
    /// fleeing during their next turn." Using the move puts the <see cref="FairyLockEffect"/> on the battle's
    /// volatile scripts so it affects the whole field.
    /// </summary>
    [Test]
    public async Task OnSecondaryEffect_AddsFairyLockEffectToBattleVolatile()
    {
        // Arrange
        var (script, move, target, _, battleVolatile) = CreateTestSetup();

        // Act
        script.OnSecondaryEffect(move, target, 0);

        // Assert
        await Assert.That(battleVolatile.Contains(ScriptUtils.ResolveName<FairyLockEffect>())).IsTrue();
    }

    /// <summary>
    /// Bulbapedia: "Fairy Lock prevents all Pokémon (except Ghost types) on the field from switching out".
    /// A non-Ghost Pokémon is prevented from switching.
    /// </summary>
    [Test]
    public async Task PreventSelfSwitch_NonGhostPokemon_SwitchPrevented()
    {
        // Arrange
        var effect = new FairyLockEffect();
        var user = CreatePokemonWithTypes("normal");
        var choice = Substitute.For<ISwitchChoice>();
        choice.User.Returns(user);
        var prevent = false;

        // Act
        effect.PreventSelfSwitch(choice, ref prevent);

        // Assert
        await Assert.That(prevent).IsTrue();
    }

    /// <summary>
    /// Bulbapedia: Fairy Lock prevents all Pokémon "(except Ghost types)" from switching out — a Ghost-type
    /// Pokémon can still switch out.
    /// </summary>
    [Test]
    public async Task PreventSelfSwitch_GhostTypePokemon_SwitchNotPrevented()
    {
        // Arrange
        var effect = new FairyLockEffect();
        var user = CreatePokemonWithTypes("ghost");
        var choice = Substitute.For<ISwitchChoice>();
        choice.User.Returns(user);
        var prevent = false;

        // Act
        effect.PreventSelfSwitch(choice, ref prevent);

        // Assert
        await Assert.That(prevent).IsFalse();
    }

    /// <summary>
    /// Bulbapedia: "Fairy Lock prevents all Pokémon (except Ghost types) on the field from switching out or
    /// fleeing during their next turn." A non-Ghost Pokémon is prevented from fleeing.
    /// </summary>
    [Test]
    public async Task PreventSelfRunAway_NonGhostPokemon_FleeingPrevented()
    {
        // Arrange
        var effect = new FairyLockEffect();
        var user = CreatePokemonWithTypes("normal");
        var choice = Substitute.For<IFleeChoice>();
        choice.User.Returns(user);
        var prevent = false;

        // Act
        effect.PreventSelfRunAway(choice, ref prevent);

        // Assert
        await Assert.That(prevent).IsTrue();
    }

    /// <summary>
    /// Bulbapedia: Fairy Lock prevents all Pokémon "(except Ghost types)" from fleeing — a Ghost-type
    /// Pokémon can still flee.
    /// </summary>
    [Test]
    public async Task PreventSelfRunAway_GhostTypePokemon_FleeingNotPrevented()
    {
        // Arrange
        var effect = new FairyLockEffect();
        var user = CreatePokemonWithTypes("ghost");
        var choice = Substitute.For<IFleeChoice>();
        choice.User.Returns(user);
        var prevent = false;

        // Act
        effect.PreventSelfRunAway(choice, ref prevent);

        // Assert
        await Assert.That(prevent).IsFalse();
    }

    /// <summary>
    /// Bulbapedia: the lock applies "during their next turn" — at the end of the turn Fairy Lock was used,
    /// the <see cref="FairyLockEffect"/> stays on the battle so the following turn is still locked.
    /// </summary>
    [Test]
    public async Task OnEndTurn_FirstEndOfTurn_EffectRemains()
    {
        // Arrange
        var (script, move, target, battle, battleVolatile) = CreateTestSetup();
        script.OnSecondaryEffect(move, target, 0);
        var effect = battleVolatile.Get<FairyLockEffect>()!;

        // Act - end of the turn Fairy Lock was used
        effect.OnEndTurn(battle, battle);

        // Assert
        await Assert.That(battleVolatile.Contains(ScriptUtils.ResolveName<FairyLockEffect>())).IsTrue();
    }

    /// <summary>
    /// Bulbapedia: the lock only lasts "during their next turn" — at the end of the turn after Fairy Lock
    /// was used, the <see cref="FairyLockEffect"/> removes itself.
    /// </summary>
    [Test]
    public async Task OnEndTurn_SecondEndOfTurn_EffectRemovesItself()
    {
        // Arrange
        var (script, move, target, battle, battleVolatile) = CreateTestSetup();
        script.OnSecondaryEffect(move, target, 0);
        var effect = battleVolatile.Get<FairyLockEffect>()!;

        // Act - end of the turn Fairy Lock was used, then end of the locked turn
        effect.OnEndTurn(battle, battle);
        effect.OnEndTurn(battle, battle);

        // Assert
        await Assert.That(battleVolatile.Contains(ScriptUtils.ResolveName<FairyLockEffect>())).IsFalse();
    }
}