using PkmnLib.Dynamic.Models;
using PkmnLib.Dynamic.Models.Choices;
using PkmnLib.Static;
using PkmnLib.Static.Utils;

namespace PkmnLib.Dynamic.AI;

/// <summary>
/// HighestDamageAI is an AI that selects the move that it expects to deal the highest damage.
/// </summary>
public class HighestDamageAI : PokemonAI
{
    /// <inheritdoc />
    public HighestDamageAI() : base("highest_damage")
    {
    }

    /// <inheritdoc />
    public override ITurnChoice GetChoice(IBattle battle, IPokemon pokemon)
    {
        var opponentSide = pokemon.BattleData!.SideIndex == 0 ? (byte)1 : (byte)0;
        var opponent = battle.Sides[opponentSide].Pokemon.WhereNotNull().FirstOrDefault(x => x.IsUsable);
        var moves = pokemon.Moves.WhereNotNull().Where(x => battle.CanUse(new MoveChoice(pokemon, x, opponentSide, 0)))
            .ToList();
        if (opponent == null)
        {
            var move = moves.FirstOrDefault();
            return move != null
                ? new MoveChoice(pokemon, move, opponentSide, 0)
                : battle.Library.MiscLibrary.ReplacementChoice(pokemon, opponentSide, 0);
        }

        var movesWithDamage = moves.Select(move =>
        {
            var hitData = new CustomHitData
            {
                BasePower = move.MoveData.BasePower,
                Effectiveness =
                    battle.Library.StaticLibrary.Types.GetEffectiveness(move.MoveData.MoveType, opponent.Types),
                Type = move.MoveData.MoveType,
            };
            return new
            {
                Move = move,
                Damage = battle.Library.DamageCalculator.GetDamage(null, move.MoveData.Category, pokemon, opponent, 1,
                    0, hitData),
            };
        }).OrderByDescending(x => x.Damage).FirstOrDefault();
        if (movesWithDamage is null)
        {
            return battle.Library.MiscLibrary.ReplacementChoice(pokemon, opponentSide, 0);
        }
        var bestMove = movesWithDamage.Move;
        return new MoveChoice(pokemon, bestMove, opponentSide, 0);
    }

    private class CustomHitData : IHitData
    {
        /// <inheritdoc />
        public bool IsCritical => false;

        /// <inheritdoc />
        public ushort BasePower { get; init; }

        /// <inheritdoc />
        public float Effectiveness { get; init; }

        /// <inheritdoc />
        public uint Damage => 0;

        /// <inheritdoc />
        public TypeIdentifier? Type { get; init; }

        /// <inheritdoc />
        public bool IsContact => false;

        /// <inheritdoc />
        public bool HasFailed => false;

        /// <inheritdoc />
        public void Fail()
        {
        }

        /// <inheritdoc />
        public void SetFlag(StringKey flag)
        {
        }

        /// <inheritdoc />
        public bool HasFlag(StringKey flag) => false;
    }
}