namespace PkmnLib.Plugin.Gen7.Scripts.Abilities;

/// <summary>
/// Illusion is an ability that disguises the Pokémon as the last non-fainted Pokémon in the party until it takes damage.
///
/// <see href="https://bulbapedia.bulbagarden.net/wiki/Illusion_(Ability)">Bulbapedia - Illusion</see>
/// </summary>
[Script(ScriptCategory.Ability, "illusion")]
public class Illusion : Script, IScriptOnIncomingHit, IScriptOnSwitchIn
{
    private IBattlePokemon? _pokemon;

    /// <inheritdoc />
    public override void OnAddedToParent(IScriptSource source)
    {
        if (source is not IBattlePokemon pokemon)
            throw new InvalidOperationException("Illusion can only be added to a Pokemon script source.");
        _pokemon = pokemon;
    }

    /// <inheritdoc />
    public void OnSwitchIn(IBattlePokemon pokemon, byte position)
    {
        var lastNonFaintedPokemon = pokemon.Battle.Parties.FirstOrDefault(p => p.BattlePokemon.Contains(pokemon))
            ?.BattlePokemon.WhereNotNull().FirstOrDefault(x => x.IsUsable);
        if (lastNonFaintedPokemon is null || lastNonFaintedPokemon == pokemon)
            return;

        pokemon.SetDisplaySpecies(lastNonFaintedPokemon.Species, lastNonFaintedPokemon.Form);
    }

    /// <inheritdoc />
    public override void OnRemove()
    {
        if (_pokemon is null)
            return;

        _pokemon.SetDisplaySpecies(null, null);
        _pokemon.Battle.EventHook.Invoke(new AbilityTriggerEvent(_pokemon));
    }

    /// <inheritdoc />
    public void OnIncomingHit(IExecutingMove move, IBattlePokemon target, byte hit)
    {
        if (_pokemon?.Battle is null)
            return;

        // Remove the illusion when the Pokémon takes damage
        _pokemon.SetDisplaySpecies(null, null);
        _pokemon.Battle.EventHook.Invoke(new AbilityTriggerEvent(_pokemon));
    }
}