PKHeX/PKHeX.Core/Legality/Encounters/EncounterSlot/GO/EncounterSlot8GO.cs

using System;

namespace PKHeX.Core
{
    /// <summary>
    /// Encounter Slot representing data transferred to <see cref="GameVersion.Gen8"/> (HOME).
    /// <inheritdoc cref="EncounterSlotGO" />
    /// </summary>
    public sealed record EncounterSlot8GO : EncounterSlotGO, IFixedOTFriendship
    {
        public override int Generation => 8;

        /// <summary>
        /// Encounters need a Parent Game to determine the original moves when transferred to HOME.
        /// </summary>
        /// <remarks>
        /// Future game releases might change this value.
        /// With respect to date legality, new dates might be incompatible with initial <seealso cref="OriginFormat"/> values.
        /// </remarks>
        public PogoImportFormat OriginFormat { get; }

        public EncounterSlot8GO(EncounterArea8g area, int species, int form, int start, int end, Shiny shiny, Gender gender, PogoType type, PogoImportFormat originFormat)
            : base(area, species, form, start, end, shiny, gender, type)
        {
            OriginFormat = originFormat;
        }

        /// <summary>
        /// Checks if the <seealso cref="Ball"/> is compatible with the <seealso cref="PogoType"/>.
        /// </summary>
        public bool IsBallValid(Ball ball, int currentSpecies)
        {
            // GO does not natively produce Shedinja when evolving Nincada, and thus must be evolved in future games.
            if (currentSpecies == (int)Core.Species.Shedinja && currentSpecies != Species)
                return ball == Ball.Poke;
            return Type.IsBallValid(ball);
        }

        protected override PKM GetBlank() => OriginFormat switch
        {
            PogoImportFormat.PK7 => new PK8(),
            PogoImportFormat.PB7 => new PB7(),
            PogoImportFormat.PK8 => new PK8(),
            PogoImportFormat.PA8 => new PA8(),
            _ => throw new ArgumentOutOfRangeException(nameof(OriginFormat)),
        };

        private PersonalInfo GetPersonal() => OriginFormat switch
        {
            PogoImportFormat.PK7 => PersonalTable.USUM.GetFormEntry(Species, Form),
            PogoImportFormat.PB7 => PersonalTable.GG.GetFormEntry(Species, Form),
            PogoImportFormat.PK8 => PersonalTable.SWSH.GetFormEntry(Species, Form),
            PogoImportFormat.PA8 => PersonalTable.LA.GetFormEntry(Species, Form),
            _ => throw new ArgumentOutOfRangeException(nameof(OriginFormat)),
        };

        internal GameVersion OriginGroup => OriginFormat switch
        {
            PogoImportFormat.PK7 => GameVersion.USUM,
            PogoImportFormat.PB7 => GameVersion.GG,
            PogoImportFormat.PK8 => GameVersion.SWSH,
            PogoImportFormat.PA8 => GameVersion.PLA,
            _ => throw new ArgumentOutOfRangeException(nameof(OriginFormat)),
        };

        protected override void ApplyDetails(ITrainerInfo sav, EncounterCriteria criteria, PKM pk)
        {
            pk.HT_Name = "PKHeX";
            pk.CurrentHandler = 1;
            if (pk is IHandlerLanguage l)
                l.HT_Language = 2;

            base.ApplyDetails(sav, criteria, pk);
            var ball = Type.GetValidBall();
            if (ball != Ball.None)
                pk.Ball = (int)ball;

            if (pk is IScaledSize s)
            {
                s.HeightScalar = PokeSizeUtil.GetRandomScalar();
                s.WeightScalar = PokeSizeUtil.GetRandomScalar();
            }

            if (OriginFormat is PogoImportFormat.PA8)
            {
                var pa8 = (PA8)pk;
                pa8.ResetHeight();
                pa8.ResetWeight();
                pa8.HeightScalarCopy = pa8.HeightScalar;
            }

            pk.OT_Friendship = OT_Friendship;

            pk.SetRandomEC();
        }

        protected override void SetPINGA(PKM pk, EncounterCriteria criteria)
        {
            var pi = GetPersonal();
            if (OriginFormat is PogoImportFormat.PK7)
                pk.EXP = Experience.GetEXP(LevelMin, pi.EXPGrowth);
            int gender = criteria.GetGender(-1, pi);
            int nature = (int)criteria.GetNature(Nature.Random);
            var ability = criteria.GetAbilityFromNumber(Ability);

            pk.PID = Util.Rand32();
            pk.Nature = pk.StatNature = nature;
            pk.Gender = gender;

            pk.AbilityNumber = 1 << ability;
            var abilities = pi.Abilities;
            if ((uint)ability < abilities.Count)
                pk.Ability = abilities[ability];

            pk.SetRandomIVsGO();
            base.SetPINGA(pk, criteria);
        }

        protected override void SetEncounterMoves(PKM pk, GameVersion version, int level)
        {
            var moves = MoveLevelUp.GetEncounterMoves(pk, level, OriginGroup);
            pk.SetMoves(moves);
            pk.SetMaximumPPCurrent(moves);
        }

        public override EncounterMatchRating GetMatchRating(PKM pkm)
        {
            if (IsMatchPartial(pkm))
                return EncounterMatchRating.PartialMatch;
            return base.GetMatchRating(pkm) == EncounterMatchRating.PartialMatch ? EncounterMatchRating.PartialMatch : EncounterMatchRating.Match;
        }

        public byte OT_Friendship => Species switch
        {
            (int)Core.Species.Timburr  when Form == 0 => 70,
            (int)Core.Species.Stunfisk when Form == 0 => 70,
            (int)Core.Species.Hoopa    when Form == 1 => 50,
            _ => GetHOMEFriendship(),
        };

        private byte GetHOMEFriendship()
        {
            var fs = (byte)GetPersonal().BaseFriendship;
            if (fs == 70)
                return 50;
            return fs;
        }

        private bool IsMatchPartial(PKM pk)
        {
            var stamp = GetTimeStamp(pk.Met_Year + 2000, pk.Met_Month, pk.Met_Day);
            if (!IsWithinStartEnd(stamp))
                return true;
            if (!GetIVsAboveMinimum(pk))
                return true;
            if (!GetIVsBelowMaximum(pk))
                return true;

            // Eevee & Glaceon have different base friendships. Make sure if it is invalid that we yield the other encounter before.
            if (pk.OT_Friendship != OT_Friendship)
                return true;

            return Species switch
            {
                (int)Core.Species.Yamask when pk.Species != Species && Form == 1 => pk is IFormArgument { FormArgument: 0 },
                (int)Core.Species.Milcery when pk.Species != Species => pk is IFormArgument { FormArgument: 0 },
                (int)Core.Species.Qwilfish when pk.Species != Species && Form == 1 => pk is IFormArgument { FormArgument: 0 },
                (int)Core.Species.Basculin when pk.Species != Species && Form == 2 => pk is IFormArgument { FormArgument: 0 },
                (int)Core.Species.Stantler when pk.Species != Species => pk is IFormArgument { FormArgument: 0 },

                (int)Core.Species.Runerigus => pk is IFormArgument { FormArgument: not 0 },
                (int)Core.Species.Alcremie => pk is IFormArgument { FormArgument: not 0 },
                (int)Core.Species.Wyrdeer => pk is IFormArgument { FormArgument: not 0 },
                (int)Core.Species.Basculegion => pk is IFormArgument { FormArgument: not 0 },
                (int)Core.Species.Overqwil => pk is IFormArgument { FormArgument: not 0 },

                _ => false,
            };
        }
    }

    public enum PogoImportFormat : byte
    {
        PK7 = 0,
        PB7 = 1,
        PK8 = 2,
        PA8 = 3,
    }
}