using System;
using System.Collections.Generic;
using static PKHeX.Core.RibbonIndex;
using static System.Buffers.Binary.BinaryPrimitives;

namespace PKHeX.Core
{
    /// <summary>
    /// Generation 8 Mystery Gift Template File
    /// </summary>
    public sealed class WC8 : DataMysteryGift, ILangNick, INature, IGigantamax, IDynamaxLevel, IRibbonIndex, IMemoryOT, ILangNicknamedTemplate,
        IRibbonSetEvent3, IRibbonSetEvent4, IRibbonSetCommon3, IRibbonSetCommon4, IRibbonSetCommon6, IRibbonSetCommon7, IRibbonSetCommon8, IRibbonSetMark8
    {
        public const int Size = 0x2D0;
        public const int CardStart = 0x0;

        public override int Generation => 8;

        public enum GiftType : byte
        {
            None = 0,
            Pokemon = 1,
            Item = 2,
            BP = 3,
            Clothing = 4,
        }

        public WC8() : this(new byte[Size]) { }
        public WC8(byte[] data) : base(data) { }

        // TODO: public byte RestrictVersion?

        public bool CanBeReceivedByVersion(int v) => v is (int) GameVersion.SW or (int) GameVersion.SH;

        // General Card Properties
        public override int CardID
        {
            get => ReadUInt16LittleEndian(Data.AsSpan(CardStart + 0x8));
            set => WriteUInt16LittleEndian(Data.AsSpan(CardStart + 0x8), (ushort)value);
        }

        public byte CardFlags { get => Data[CardStart + 0x10]; set => Data[CardStart + 0x10] = value; }
        public GiftType CardType { get => (GiftType)Data[CardStart + 0x11]; set => Data[CardStart + 0x11] = (byte)value; }
        public bool GiftRepeatable { get => (CardFlags & 1) == 0; set => CardFlags = (byte)((CardFlags & ~1) | (value ? 0 : 1)); }
        public override bool GiftUsed { get => false; set { }  }

        public int CardTitleIndex
        {
            get => Data[CardStart + 0x15];
            set => Data[CardStart + 0x15] = (byte) value;
        }

        public override string CardTitle
        {
            get => "Mystery Gift"; // TODO: Use text string from CardTitleIndex
            set => throw new Exception();
        }

        // Item Properties
        public override bool IsItem { get => CardType == GiftType.Item; set { if (value) CardType = GiftType.Item; } }

        public override int ItemID
        {
            get => GetItem(0);
            set => SetItem(0, (ushort)value);
        }

        public override int Quantity
        {
            get => GetQuantity(0);
            set => SetQuantity(0, (ushort)value);
        }

        public int GetItem(int index) => ReadUInt16LittleEndian(Data.AsSpan(CardStart + 0x20 + (0x4 * index)));
        public void SetItem(int index, ushort item) => WriteUInt16LittleEndian(Data.AsSpan(CardStart + 0x20 + (4 * index)), item);
        public int GetQuantity(int index) => ReadUInt16LittleEndian(Data.AsSpan(CardStart + 0x22 + (0x4 * index)));
        public void SetQuantity(int index, ushort quantity) => WriteUInt16LittleEndian(Data.AsSpan(CardStart + 0x22 + (4 * index)), quantity);

        // Pokémon Properties
        public override bool IsPokémon { get => CardType == GiftType.Pokemon; set { if (value) CardType = GiftType.Pokemon; } }

        public override bool IsShiny => Shiny.IsShiny();

        public override Shiny Shiny
        {
            get
            {
                var type = PIDType;
                if (type is not Shiny.FixedValue)
                    return type;
                if (IsHOMEGift && IsHOMEShinyPossible())
                    return Shiny.Random;
                return GetShinyXor() switch
                {
                    0 => Shiny.AlwaysSquare,
                    <= 15 => Shiny.AlwaysStar,
                    _ => Shiny.Never,
                };
            }
        }

        private int GetShinyXor()
        {
            // Player owned anti-shiny fixed PID
            if (TID == 0 && SID == 0)
                return int.MaxValue;

            var pid = PID;
            var psv = (int)(pid >> 16 ^ (pid & 0xFFFF));
            var tsv = (TID ^ SID);
            return psv ^ tsv;
        }

        public override int TID
        {
            get => ReadUInt16LittleEndian(Data.AsSpan(CardStart + 0x20));
            set => WriteUInt16LittleEndian(Data.AsSpan(CardStart + 0x20), (ushort)value);
        }

        public override int SID {
            get => ReadUInt16LittleEndian(Data.AsSpan(CardStart + 0x22));
            set => WriteUInt16LittleEndian(Data.AsSpan(CardStart + 0x22), (ushort)value);
        }

        public int OriginGame
        {
            get => ReadInt32LittleEndian(Data.AsSpan(CardStart + 0x24));
            set => WriteInt32LittleEndian(Data.AsSpan(CardStart + 0x24), value);
        }

        public uint EncryptionConstant
        {
            get => ReadUInt32LittleEndian(Data.AsSpan(CardStart + 0x28));
            set => WriteUInt32LittleEndian(Data.AsSpan(CardStart + 0x28), value);
        }

        public uint PID
        {
            get => ReadUInt32LittleEndian(Data.AsSpan(CardStart + 0x2C));
            set => WriteUInt32LittleEndian(Data.AsSpan(CardStart + 0x2C), value);
        }

        // Nicknames, OT Names 0x30 - 0x228
        public override int EggLocation { get => ReadUInt16LittleEndian(Data.AsSpan(CardStart + 0x228)); set => WriteUInt16LittleEndian(Data.AsSpan(CardStart + 0x228), (ushort)value); }
        public int MetLocation { get => ReadUInt16LittleEndian(Data.AsSpan(CardStart + 0x22A)); set => WriteUInt16LittleEndian(Data.AsSpan(CardStart + 0x22A), (ushort)value); }

        public override int Ball
        {
            get => ReadUInt16LittleEndian(Data.AsSpan(CardStart + 0x22C));
            set => WriteUInt16LittleEndian(Data.AsSpan(CardStart + 0x22C), (ushort)value);
        }

        public override int HeldItem
        {
            get => ReadUInt16LittleEndian(Data.AsSpan(CardStart + 0x22E));
            set => WriteUInt16LittleEndian(Data.AsSpan(CardStart + 0x22E), (ushort)value);
        }

        public int Move1 { get => ReadUInt16LittleEndian(Data.AsSpan(CardStart + 0x230)); set => WriteUInt16LittleEndian(Data.AsSpan(CardStart + 0x230), (ushort)value); }
        public int Move2 { get => ReadUInt16LittleEndian(Data.AsSpan(CardStart + 0x232)); set => WriteUInt16LittleEndian(Data.AsSpan(CardStart + 0x232), (ushort)value); }
        public int Move3 { get => ReadUInt16LittleEndian(Data.AsSpan(CardStart + 0x234)); set => WriteUInt16LittleEndian(Data.AsSpan(CardStart + 0x234), (ushort)value); }
        public int Move4 { get => ReadUInt16LittleEndian(Data.AsSpan(CardStart + 0x236)); set => WriteUInt16LittleEndian(Data.AsSpan(CardStart + 0x236), (ushort)value); }
        public int RelearnMove1 { get => ReadUInt16LittleEndian(Data.AsSpan(CardStart + 0x238)); set => WriteUInt16LittleEndian(Data.AsSpan(CardStart + 0x238), (ushort)value); }
        public int RelearnMove2 { get => ReadUInt16LittleEndian(Data.AsSpan(CardStart + 0x23A)); set => WriteUInt16LittleEndian(Data.AsSpan(CardStart + 0x23A), (ushort)value); }
        public int RelearnMove3 { get => ReadUInt16LittleEndian(Data.AsSpan(CardStart + 0x23C)); set => WriteUInt16LittleEndian(Data.AsSpan(CardStart + 0x23C), (ushort)value); }
        public int RelearnMove4 { get => ReadUInt16LittleEndian(Data.AsSpan(CardStart + 0x23E)); set => WriteUInt16LittleEndian(Data.AsSpan(CardStart + 0x23E), (ushort)value); }

        public override int Species { get => ReadUInt16LittleEndian(Data.AsSpan(CardStart + 0x240)); set => WriteUInt16LittleEndian(Data.AsSpan(CardStart + 0x240), (ushort)value); }
        public override int Form { get => Data[CardStart + 0x242]; set => Data[CardStart + 0x242] = (byte)value; }
        public override int Gender { get => Data[CardStart + 0x243]; set => Data[CardStart + 0x243] = (byte)value; }
        public override int Level { get => Data[CardStart + 0x244]; set => Data[CardStart + 0x244] = (byte)value; }
        public override bool IsEgg { get => Data[CardStart + 0x245] == 1; set => Data[CardStart + 0x245] = value ? (byte)1 : (byte)0; }
        public int Nature { get => (sbyte)Data[CardStart + 0x246]; set => Data[CardStart + 0x246] = (byte)value; }
        public override int AbilityType { get => Data[CardStart + 0x247]; set => Data[CardStart + 0x247] = (byte)value; }

        private byte PIDTypeValue => Data[CardStart + 0x248];

        public Shiny PIDType => PIDTypeValue switch
        {
            0 => Shiny.Never,
            1 => Shiny.Random,
            2 => Shiny.AlwaysStar,
            3 => Shiny.AlwaysSquare,
            4 => Shiny.FixedValue,
            _ => throw new ArgumentOutOfRangeException(nameof(PIDType)),
        };

        public int MetLevel { get => Data[CardStart + 0x249]; set => Data[CardStart + 0x249] = (byte)value; }
        public byte DynamaxLevel { get => Data[CardStart + 0x24A]; set => Data[CardStart + 0x24A] = value; }
        public bool CanGigantamax { get => Data[CardStart + 0x24B] != 0; set => Data[CardStart + 0x24B] = value ? (byte)1 : (byte)0; }

        // Ribbons 0x24C-0x26C
        private const int RibbonBytesOffset = 0x24C;
        private const int RibbonBytesCount = 0x20;
        private const int RibbonByteNone = 0xFF; // signed -1

        public bool HasMark()
        {
            for (int i = 0; i < RibbonBytesCount; i++)
            {
                var value = Data[RibbonBytesOffset + i];
                if (value == RibbonByteNone)
                    return false;
                if ((RibbonIndex)value is >= MarkLunchtime and <= MarkSlump)
                    return true;
            }
            return false;
        }

        public byte GetRibbonAtIndex(int byteIndex)
        {
            if ((uint)byteIndex >= RibbonBytesCount)
                throw new IndexOutOfRangeException();
            return Data[RibbonBytesOffset + byteIndex];
        }

        public void SetRibbonAtIndex(int byteIndex, byte ribbonIndex)
        {
            if ((uint)byteIndex >= RibbonBytesCount)
                throw new IndexOutOfRangeException();
            Data[RibbonBytesOffset + byteIndex] = ribbonIndex;
        }

        public int IV_HP  { get => Data[CardStart + 0x26C]; set => Data[CardStart + 0x26C] = (byte)value; }
        public int IV_ATK { get => Data[CardStart + 0x26D]; set => Data[CardStart + 0x26D] = (byte)value; }
        public int IV_DEF { get => Data[CardStart + 0x26E]; set => Data[CardStart + 0x26E] = (byte)value; }
        public int IV_SPE { get => Data[CardStart + 0x26F]; set => Data[CardStart + 0x26F] = (byte)value; }
        public int IV_SPA { get => Data[CardStart + 0x270]; set => Data[CardStart + 0x270] = (byte)value; }
        public int IV_SPD { get => Data[CardStart + 0x271]; set => Data[CardStart + 0x271] = (byte)value; }

        public int OTGender { get => Data[CardStart + 0x272]; set => Data[CardStart + 0x272] = (byte)value; }

        public int EV_HP  { get => Data[CardStart + 0x273]; set => Data[CardStart + 0x273] = (byte)value; }
        public int EV_ATK { get => Data[CardStart + 0x274]; set => Data[CardStart + 0x274] = (byte)value; }
        public int EV_DEF { get => Data[CardStart + 0x275]; set => Data[CardStart + 0x275] = (byte)value; }
        public int EV_SPE { get => Data[CardStart + 0x276]; set => Data[CardStart + 0x276] = (byte)value; }
        public int EV_SPA { get => Data[CardStart + 0x277]; set => Data[CardStart + 0x277] = (byte)value; }
        public int EV_SPD { get => Data[CardStart + 0x278]; set => Data[CardStart + 0x278] = (byte)value; }

        public int OT_Intensity { get => Data[CardStart + 0x279]; set => Data[CardStart + 0x279] = (byte)value; }
        public int OT_Memory { get => Data[CardStart + 0x27A]; set => Data[CardStart + 0x27A] = (byte)value; }
        public int OT_Feeling { get => Data[CardStart + 0x27B]; set => Data[CardStart + 0x27B] = (byte)value; }
        public int OT_TextVar { get => ReadUInt16LittleEndian(Data.AsSpan(CardStart + 0x27C)); set => WriteUInt16LittleEndian(Data.AsSpan(CardStart + 0x27C), (ushort)value); }

        // Meta Accessible Properties
        public override int[] IVs
        {
            get => new[] { IV_HP, IV_ATK, IV_DEF, IV_SPE, IV_SPA, IV_SPD };
            set
            {
                if (value.Length != 6) return;
                IV_HP = value[0]; IV_ATK = value[1]; IV_DEF = value[2];
                IV_SPE = value[3]; IV_SPA = value[4]; IV_SPD = value[5];
            }
        }

        public int[] EVs
        {
            get => new[] { EV_HP, EV_ATK, EV_DEF, EV_SPE, EV_SPA, EV_SPD };
            set
            {
                if (value.Length != 6) return;
                EV_HP = value[0]; EV_ATK = value[1]; EV_DEF = value[2];
                EV_SPE = value[3]; EV_SPA = value[4]; EV_SPD = value[5];
            }
        }

        public bool GetIsNicknamed(int language) => ReadUInt16LittleEndian(Data.AsSpan(GetNicknameOffset(language))) != 0;

        public bool CanBeAnyLanguage()
        {
            for (int i = 0; i < 9; i++)
            {
                var ofs = GetLanguageOffset(i);
                var lang = ReadInt16LittleEndian(Data.AsSpan(ofs));
                if (lang != 0)
                    return false;
            }
            return true;
        }

        public bool CanHaveLanguage(int language)
        {
            if (language is < (int)LanguageID.Japanese or > (int)LanguageID.ChineseT)
                return false;

            if (CanBeAnyLanguage())
                return true;

            for (int i = 0; i < 9; i++)
            {
                var ofs = GetLanguageOffset(i);
                var lang = ReadInt16LittleEndian(Data.AsSpan(ofs));
                if (lang == language)
                    return true;
            }
            return false;
        }

        public int GetLanguage(int redeemLanguage) => Data[GetLanguageOffset(GetLanguageIndex(redeemLanguage))];
        private static int GetLanguageOffset(int index) => 0x30 + (index * 0x1C) + 0x1A;

        public bool GetHasOT(int language) => ReadUInt16LittleEndian(Data.AsSpan(GetOTOffset(language))) != 0;

        private static int GetLanguageIndex(int language)
        {
            var lang = (LanguageID) language;
            if (lang is < LanguageID.Japanese or LanguageID.UNUSED_6 or > LanguageID.ChineseT)
                return (int) LanguageID.English; // fallback
            return lang < LanguageID.UNUSED_6 ? language - 1 : language - 2;
        }

        public override int Location { get => MetLocation; set => MetLocation = (ushort)value; }

        public override IReadOnlyList<int> Moves
        {
            get => new[] { Move1, Move2, Move3, Move4 };
            set
            {
                if (value.Count > 0) Move1 = value[0];
                if (value.Count > 1) Move2 = value[1];
                if (value.Count > 2) Move3 = value[2];
                if (value.Count > 3) Move4 = value[3];
            }
        }

        public override IReadOnlyList<int> Relearn
        {
            get => new[] { RelearnMove1, RelearnMove2, RelearnMove3, RelearnMove4 };
            set
            {
                if (value.Count > 0) RelearnMove1 = value[0];
                if (value.Count > 1) RelearnMove2 = value[1];
                if (value.Count > 2) RelearnMove3 = value[2];
                if (value.Count > 3) RelearnMove4 = value[3];
            }
        }

        public override string OT_Name { get; set; } = string.Empty;
        public string Nickname => string.Empty;
        public bool IsNicknamed => false;
        public int Language => 2;

        public string GetNickname(int language) => StringConverter8.GetString(Data.AsSpan(GetNicknameOffset(language), 0x1A));
        public void SetNickname(int language, string value) => StringConverter8.SetString(Data.AsSpan(GetNicknameOffset(language), 0x1A), value.AsSpan(), 12, StringConverterOption.ClearZero);

        public string GetOT(int language) => StringConverter8.GetString(Data.AsSpan(GetOTOffset(language), 0x1A));
        public void SetOT(int language, string value) => StringConverter8.SetString(Data.AsSpan(GetOTOffset(language), 0x1A), value.AsSpan(), 12, StringConverterOption.ClearZero);

        private static int GetNicknameOffset(int language)
        {
            int index = GetLanguageIndex(language);
            return 0x30 + (index * 0x1C);
        }

        private static int GetOTOffset(int language)
        {
            int index = GetLanguageIndex(language);
            return 0x12C + (index * 0x1C);
        }

        public bool IsHOMEGift => CardID >= 9000;

        public bool CanHandleOT(int language) => !GetHasOT(language);

        public override GameVersion Version
        {
            get => OriginGame != 0 ? (GameVersion)OriginGame : GameVersion.SWSH;
            set { }
        }

        public override PKM ConvertToPKM(ITrainerInfo sav, EncounterCriteria criteria)
        {
            if (!IsPokémon)
                throw new ArgumentException(nameof(IsPokémon));

            int currentLevel = Level > 0 ? Level : (1 + Util.Rand.Next(100));
            int metLevel = MetLevel > 0 ? MetLevel : currentLevel;
            var pi = PersonalTable.SWSH.GetFormEntry(Species, Form);
            var language = sav.Language;
            var OT = GetOT(language);
            bool hasOT = GetHasOT(language);

            var pk = new PK8
            {
                EncryptionConstant = EncryptionConstant != 0 || IsHOMEGift ? EncryptionConstant : Util.Rand32(),
                TID = TID,
                SID = SID,
                Species = Species,
                Form = Form,
                CurrentLevel = currentLevel,
                Ball = Ball != 0 ? Ball : 4, // Default is Pokeball
                Met_Level = metLevel,
                HeldItem = HeldItem,

                EXP = Experience.GetEXP(currentLevel, pi.EXPGrowth),

                Move1 = Move1,
                Move2 = Move2,
                Move3 = Move3,
                Move4 = Move4,
                RelearnMove1 = RelearnMove1,
                RelearnMove2 = RelearnMove2,
                RelearnMove3 = RelearnMove3,
                RelearnMove4 = RelearnMove4,

                Version = OriginGame != 0 ? OriginGame : sav.Game,

                OT_Name = OT.Length > 0 ? OT : sav.OT,
                OT_Gender = OTGender < 2 ? OTGender : sav.Gender,
                HT_Name = hasOT ? sav.OT : string.Empty,
                HT_Gender = hasOT ? sav.Gender : 0,
                HT_Language = hasOT ? language : 0,
                CurrentHandler = hasOT ? 1 : 0,
                OT_Friendship = pi.BaseFriendship,

                OT_Intensity = OT_Intensity,
                OT_Memory = OT_Memory,
                OT_TextVar = OT_TextVar,
                OT_Feeling = OT_Feeling,
                FatefulEncounter = true,

                EVs = EVs,

                CanGigantamax = CanGigantamax,
                DynamaxLevel = DynamaxLevel,

                Met_Location = MetLocation,
                Egg_Location = EggLocation,
            };
            pk.SetMaximumPPCurrent();

            if ((sav.Generation > Generation && OriginGame == 0) || !CanBeReceivedByVersion(pk.Version))
            {
                // give random valid game
                var rnd = Util.Rand;
                do { pk.Version = (int)GameVersion.SW + rnd.Next(2); }
                while (!CanBeReceivedByVersion(pk.Version));
            }

            if (OTGender >= 2)
            {
                pk.TID = sav.TID;
                pk.SID = sav.SID;

                if (IsHOMEGift)
                {
                    pk.TrainerSID7 = 0;
                    while (pk.TSV == 0)
                    {
                        pk.TrainerID7 = Util.Rand.Next(16, 999_999 + 1);
                    }
                }
            }

            // Official code explicitly corrects for Meowstic
            if (pk.Species == (int)Core.Species.Meowstic)
                pk.Form = pk.Gender;

            pk.MetDate = IsHOMEGift && EncountersHOME.WC8Gifts.TryGetValue(CardID, out var dt) ? dt : DateTime.Now;

            var nickname_language = GetLanguage(language);
            pk.Language = nickname_language != 0 ? nickname_language : sav.Language;
            pk.IsNicknamed = GetIsNicknamed(language);
            pk.Nickname = pk.IsNicknamed ? GetNickname(language) : SpeciesName.GetSpeciesNameGeneration(Species, pk.Language, Generation);

            for (var i = 0; i < RibbonBytesCount; i++)
            {
                var ribbon = GetRibbonAtIndex(i);
                if (ribbon != RibbonByteNone)
                    pk.SetRibbon(ribbon);
            }

            SetPINGA(pk, criteria);

            if (IsEgg)
                SetEggMetData(pk);
            pk.CurrentFriendship = pk.IsEgg ? pi.HatchCycles : pi.BaseFriendship;

            if (!IsHOMEGift)
            {
                pk.HeightScalar = PokeSizeUtil.GetRandomScalar();
                pk.WeightScalar = PokeSizeUtil.GetRandomScalar();
            }

            pk.ResetPartyStats();
            pk.RefreshChecksum();
            return pk;
        }

        private void SetEggMetData(PKM pk)
        {
            pk.IsEgg = true;
            pk.EggMetDate = DateTime.Now;
            pk.Nickname = SpeciesName.GetSpeciesNameGeneration(0, pk.Language, Generation);
            pk.IsNicknamed = true;
        }

        private void SetPINGA(PKM pk, EncounterCriteria criteria)
        {
            var pi = PersonalTable.SWSH.GetFormEntry(Species, Form);
            pk.Nature = (int)criteria.GetNature(Nature == -1 ? Core.Nature.Random : (Nature)Nature);
            pk.StatNature = pk.Nature;
            pk.Gender = criteria.GetGender(Gender, pi);
            var av = GetAbilityIndex(criteria);
            pk.RefreshAbility(av);
            SetPID(pk);
            SetIVs(pk);
        }

        private int GetAbilityIndex(EncounterCriteria criteria) => AbilityType switch
        {
            00 or 01 or 02 => AbilityType, // Fixed 0/1/2
            03 or 04 => criteria.GetAbilityFromNumber(Ability), // 0/1 or 0/1/H
            _ => throw new ArgumentOutOfRangeException(nameof(AbilityType)),
        };

        public override AbilityPermission Ability => AbilityType switch
        {
            0 => AbilityPermission.OnlyFirst,
            1 => AbilityPermission.OnlySecond,
            2 => AbilityPermission.OnlyHidden,
            3 => AbilityPermission.Any12,
            _ => AbilityPermission.Any12H,
        };

        private uint GetPID(ITrainerID tr, byte type)
        {
            return type switch
            {
                0 => GetAntishiny(tr), // Random, Never Shiny
                1 => Util.Rand32(), // Random, Any
                2 => (uint) (((tr.TID ^ tr.SID ^ (PID & 0xFFFF) ^ 1) << 16) | (PID & 0xFFFF)), // Fixed, Force Star
                3 => (uint) (((tr.TID ^ tr.SID ^ (PID & 0xFFFF) ^ 0) << 16) | (PID & 0xFFFF)), // Fixed, Force Square
                4 => PID, // Fixed, Force Value
                _ => throw new ArgumentOutOfRangeException(nameof(type)),
            };

            static uint GetAntishiny(ITrainerID tr)
            {
                var pid = Util.Rand32();
                if (tr.IsShiny(pid, 8))
                    return pid ^ 0x1000_0000;
                return pid;
            }
        }

        private void SetPID(PKM pk)
        {
            pk.PID = GetPID(pk, PIDTypeValue);
        }

        private void SetIVs(PKM pk)
        {
            Span<int> finalIVs = stackalloc int[6];
            var ivflag = Array.Find(IVs, iv => (byte)(iv - 0xFC) < 3);
            var rng = Util.Rand;
            if (ivflag == 0) // Random IVs
            {
                for (int i = 0; i < 6; i++)
                    finalIVs[i] = IVs[i] > 31 ? rng.Next(32) : IVs[i];
            }
            else // 1/2/3 perfect IVs
            {
                int IVCount = ivflag - 0xFB;
                do { finalIVs[rng.Next(6)] = 31; }
                while (finalIVs.Count(31) < IVCount);
                for (int i = 0; i < 6; i++)
                    finalIVs[i] = finalIVs[i] == 31 ? 31 : rng.Next(32);
            }
            pk.SetIVs(finalIVs);
        }

        public override bool IsMatchExact(PKM pkm, DexLevel evo)
        {
            if (pkm.Egg_Location == 0) // Not Egg
            {
                if (OTGender < 2)
                {
                    if (SID != pkm.SID) return false;
                    if (TID != pkm.TID) return false;
                    if (OTGender != pkm.OT_Gender) return false;
                }

                if (!CanBeAnyLanguage() && !CanHaveLanguage(pkm.Language))
                    return false;

                var OT = GetOT(pkm.Language); // May not be guaranteed to work.
                if (!string.IsNullOrEmpty(OT) && OT != pkm.OT_Name) return false;
                if (OriginGame != 0 && OriginGame != pkm.Version) return false;
                if (EncryptionConstant != 0)
                {
                    if (EncryptionConstant != pkm.EncryptionConstant)
                        return false;
                }
                else if (IsHOMEGift)// 0
                {
                    // HOME gifts -- PID and EC are zeroes...
                    if (EncryptionConstant != pkm.EncryptionConstant)
                        return false;

                    if (pkm.TSV == 0) // HOME doesn't assign TSV=0 to accounts.
                        return false;

                    if (IsShiny)
                    {
                        if (!pkm.IsShiny)
                            return false;
                    }
                    else // Never or Random (HOME ID specific)
                    {
                        if (pkm.IsShiny && !IsHOMEShinyPossible())
                            return false;
                    }
                }
            }

            if (Form != evo.Form && !FormInfo.IsFormChangeable(Species, Form, pkm.Form, pkm.Format))
                return false;

            if (IsEgg)
            {
                if (EggLocation != pkm.Egg_Location) // traded
                {
                    if (pkm.Egg_Location != Locations.LinkTrade6)
                        return false;
                    if (PIDType == Shiny.Random && pkm.IsShiny && pkm.ShinyXor > 1)
                        return false; // shiny traded egg will always have xor0/1.
                }
                if (!PIDType.IsValid(pkm))
                {
                    return false; // can't be traded away for unshiny
                }

                if (pkm.IsEgg && !pkm.IsNative)
                    return false;
            }
            else
            {
                if (!PIDType.IsValid(pkm)) return false;
                if (EggLocation != pkm.Egg_Location) return false;
                if (MetLocation != pkm.Met_Location) return false;
            }

            if (MetLevel != 0 && MetLevel != pkm.Met_Level) return false;
            if ((Ball == 0 ? 4 : Ball) != pkm.Ball) return false;
            if (OTGender < 2 && OTGender != pkm.OT_Gender) return false;
            if (Nature != -1 && pkm.Nature != Nature) return false;
            if (Gender != 3 && Gender != pkm.Gender) return false;

            if (pkm is IGigantamax g && g.CanGigantamax != CanGigantamax && !g.CanToggleGigantamax(pkm.Species, pkm.Form, Species, Form))
                return false;

            if (pkm is not IDynamaxLevel dl || dl.DynamaxLevel < DynamaxLevel)
                return false;

            if (IsHOMEGift && pkm is IScaledSize s)
            {
                if (s.HeightScalar != 0)
                    return false;
                if (s.WeightScalar != 0)
                    return false;
            }

            // Duplicate card; one with Nickname specified and another without.
            if (CardID == 0122 && pkm.IsNicknamed != GetIsNicknamed(pkm.Language))
                return false;

            // PID Types 0 and 1 do not use the fixed PID value.
            // Values 2,3 are specific shiny states, and 4 is fixed value.
            // 2,3,4 can change if it is a traded egg to ensure the same shiny state.
            var type = PIDTypeValue;
            if (type <= 1)
                return true;
            return pkm.PID == GetPID(pkm, type);
        }

        private bool IsHOMEShinyPossible()
        {
            // no defined TID/SID and having a fixed PID can cause the player's TID/SID to match the PID's shiny calc.
            return TID == 0 && SID == 0 && PID != 0;
        }

        protected override bool IsMatchDeferred(PKM pkm) => Species != pkm.Species;
        protected override bool IsMatchPartial(PKM pkm) => false; // no version compatibility checks yet.

        #region Lazy Ribbon Implementation
        public bool RibbonEarth { get => this.GetRibbonIndex(Earth); set => this.SetRibbonIndex(Earth, value); }
        public bool RibbonNational { get => this.GetRibbonIndex(National); set => this.SetRibbonIndex(National, value); }
        public bool RibbonCountry { get => this.GetRibbonIndex(Country); set => this.SetRibbonIndex(Country, value); }
        public bool RibbonChampionBattle { get => this.GetRibbonIndex(ChampionBattle); set => this.SetRibbonIndex(ChampionBattle, value); }
        public bool RibbonChampionRegional { get => this.GetRibbonIndex(ChampionRegional); set => this.SetRibbonIndex(ChampionRegional, value); }
        public bool RibbonChampionNational { get => this.GetRibbonIndex(ChampionNational); set => this.SetRibbonIndex(ChampionNational, value); }
        public bool RibbonClassic { get => this.GetRibbonIndex(Classic); set => this.SetRibbonIndex(Classic, value); }
        public bool RibbonWishing { get => this.GetRibbonIndex(Wishing); set => this.SetRibbonIndex(Wishing, value); }
        public bool RibbonPremier { get => this.GetRibbonIndex(Premier); set => this.SetRibbonIndex(Premier, value); }
        public bool RibbonEvent { get => this.GetRibbonIndex(Event); set => this.SetRibbonIndex(Event, value); }
        public bool RibbonBirthday { get => this.GetRibbonIndex(Birthday); set => this.SetRibbonIndex(Birthday, value); }
        public bool RibbonSpecial { get => this.GetRibbonIndex(Special); set => this.SetRibbonIndex(Special, value); }
        public bool RibbonWorld { get => this.GetRibbonIndex(World); set => this.SetRibbonIndex(World, value); }
        public bool RibbonChampionWorld { get => this.GetRibbonIndex(ChampionWorld); set => this.SetRibbonIndex(ChampionWorld, value); }
        public bool RibbonSouvenir { get => this.GetRibbonIndex(Souvenir); set => this.SetRibbonIndex(Souvenir, value); }
        public bool RibbonChampionG3 { get => this.GetRibbonIndex(ChampionG3); set => this.SetRibbonIndex(ChampionG3, value); }
        public bool RibbonArtist { get => this.GetRibbonIndex(Artist); set => this.SetRibbonIndex(Artist, value); }
        public bool RibbonEffort { get => this.GetRibbonIndex(Effort); set => this.SetRibbonIndex(Effort, value); }
        public bool RibbonChampionSinnoh { get => this.GetRibbonIndex(ChampionSinnoh); set => this.SetRibbonIndex(ChampionSinnoh, value); }
        public bool RibbonAlert { get => this.GetRibbonIndex(Alert); set => this.SetRibbonIndex(Alert, value); }
        public bool RibbonShock { get => this.GetRibbonIndex(Shock); set => this.SetRibbonIndex(Shock, value); }
        public bool RibbonDowncast { get => this.GetRibbonIndex(Downcast); set => this.SetRibbonIndex(Downcast, value); }
        public bool RibbonCareless { get => this.GetRibbonIndex(Careless); set => this.SetRibbonIndex(Careless, value); }
        public bool RibbonRelax { get => this.GetRibbonIndex(Relax); set => this.SetRibbonIndex(Relax, value); }
        public bool RibbonSnooze { get => this.GetRibbonIndex(Snooze); set => this.SetRibbonIndex(Snooze, value); }
        public bool RibbonSmile { get => this.GetRibbonIndex(Smile); set => this.SetRibbonIndex(Smile, value); }
        public bool RibbonGorgeous { get => this.GetRibbonIndex(Gorgeous); set => this.SetRibbonIndex(Gorgeous, value); }
        public bool RibbonRoyal { get => this.GetRibbonIndex(Royal); set => this.SetRibbonIndex(Royal, value); }
        public bool RibbonGorgeousRoyal { get => this.GetRibbonIndex(GorgeousRoyal); set => this.SetRibbonIndex(GorgeousRoyal, value); }
        public bool RibbonFootprint { get => this.GetRibbonIndex(Footprint); set => this.SetRibbonIndex(Footprint, value); }
        public bool RibbonRecord { get => this.GetRibbonIndex(Record); set => this.SetRibbonIndex(Record, value); }
        public bool RibbonLegend { get => this.GetRibbonIndex(Legend); set => this.SetRibbonIndex(Legend, value); }
        public bool RibbonChampionKalos { get => this.GetRibbonIndex(ChampionKalos); set => this.SetRibbonIndex(ChampionKalos, value); }
        public bool RibbonChampionG6Hoenn { get => this.GetRibbonIndex(ChampionG6Hoenn); set => this.SetRibbonIndex(ChampionG6Hoenn, value); }
        public bool RibbonBestFriends { get => this.GetRibbonIndex(BestFriends); set => this.SetRibbonIndex(BestFriends, value); }
        public bool RibbonTraining { get => this.GetRibbonIndex(Training); set => this.SetRibbonIndex(Training, value); }
        public bool RibbonBattlerSkillful { get => this.GetRibbonIndex(BattlerSkillful); set => this.SetRibbonIndex(BattlerSkillful, value); }
        public bool RibbonBattlerExpert { get => this.GetRibbonIndex(BattlerExpert); set => this.SetRibbonIndex(BattlerExpert, value); }
        public bool RibbonContestStar { get => this.GetRibbonIndex(ContestStar); set => this.SetRibbonIndex(ContestStar, value); }
        public bool RibbonMasterCoolness { get => this.GetRibbonIndex(MasterCoolness); set => this.SetRibbonIndex(MasterCoolness, value); }
        public bool RibbonMasterBeauty { get => this.GetRibbonIndex(MasterBeauty); set => this.SetRibbonIndex(MasterBeauty, value); }
        public bool RibbonMasterCuteness { get => this.GetRibbonIndex(MasterCuteness); set => this.SetRibbonIndex(MasterCuteness, value); }
        public bool RibbonMasterCleverness { get => this.GetRibbonIndex(MasterCleverness); set => this.SetRibbonIndex(MasterCleverness, value); }
        public bool RibbonMasterToughness { get => this.GetRibbonIndex(MasterToughness); set => this.SetRibbonIndex(MasterToughness, value); }

        public int RibbonCountMemoryContest { get => 0; set { } }
        public int RibbonCountMemoryBattle { get => 0; set { } }

        public bool RibbonChampionAlola { get => this.GetRibbonIndex(ChampionAlola); set => this.SetRibbonIndex(ChampionAlola, value); }
        public bool RibbonBattleRoyale { get => this.GetRibbonIndex(BattleRoyale); set => this.SetRibbonIndex(BattleRoyale, value); }
        public bool RibbonBattleTreeGreat { get => this.GetRibbonIndex(BattleTreeGreat); set => this.SetRibbonIndex(BattleTreeGreat, value); }
        public bool RibbonBattleTreeMaster { get => this.GetRibbonIndex(BattleTreeMaster); set => this.SetRibbonIndex(BattleTreeMaster, value); }
        public bool RibbonChampionGalar { get => this.GetRibbonIndex(ChampionGalar); set => this.SetRibbonIndex(ChampionGalar, value); }
        public bool RibbonTowerMaster { get => this.GetRibbonIndex(TowerMaster); set => this.SetRibbonIndex(TowerMaster, value); }
        public bool RibbonMasterRank { get => this.GetRibbonIndex(MasterRank); set => this.SetRibbonIndex(MasterRank, value); }
        public bool RibbonMarkLunchtime { get => this.GetRibbonIndex(MarkLunchtime); set => this.SetRibbonIndex(MarkLunchtime, value); }
        public bool RibbonMarkSleepyTime { get => this.GetRibbonIndex(MarkSleepyTime); set => this.SetRibbonIndex(MarkSleepyTime, value); }
        public bool RibbonMarkDusk { get => this.GetRibbonIndex(MarkDusk); set => this.SetRibbonIndex(MarkDusk, value); }
        public bool RibbonMarkDawn { get => this.GetRibbonIndex(MarkDawn); set => this.SetRibbonIndex(MarkDawn, value); }
        public bool RibbonMarkCloudy { get => this.GetRibbonIndex(MarkCloudy); set => this.SetRibbonIndex(MarkCloudy, value); }
        public bool RibbonMarkRainy { get => this.GetRibbonIndex(MarkRainy); set => this.SetRibbonIndex(MarkRainy, value); }
        public bool RibbonMarkStormy { get => this.GetRibbonIndex(MarkStormy); set => this.SetRibbonIndex(MarkStormy, value); }
        public bool RibbonMarkSnowy { get => this.GetRibbonIndex(MarkSnowy); set => this.SetRibbonIndex(MarkSnowy, value); }
        public bool RibbonMarkBlizzard { get => this.GetRibbonIndex(MarkBlizzard); set => this.SetRibbonIndex(MarkBlizzard, value); }
        public bool RibbonMarkDry { get => this.GetRibbonIndex(MarkDry); set => this.SetRibbonIndex(MarkDry, value); }
        public bool RibbonMarkSandstorm { get => this.GetRibbonIndex(MarkSandstorm); set => this.SetRibbonIndex(MarkSandstorm, value); }
        public bool RibbonMarkMisty { get => this.GetRibbonIndex(MarkMisty); set => this.SetRibbonIndex(MarkMisty, value); }
        public bool RibbonMarkDestiny { get => this.GetRibbonIndex(MarkDestiny); set => this.SetRibbonIndex(MarkDestiny, value); }
        public bool RibbonMarkFishing { get => this.GetRibbonIndex(MarkFishing); set => this.SetRibbonIndex(MarkFishing, value); }
        public bool RibbonMarkCurry { get => this.GetRibbonIndex(MarkCurry); set => this.SetRibbonIndex(MarkCurry, value); }
        public bool RibbonMarkUncommon { get => this.GetRibbonIndex(MarkUncommon); set => this.SetRibbonIndex(MarkUncommon, value); }
        public bool RibbonMarkRare { get => this.GetRibbonIndex(MarkRare); set => this.SetRibbonIndex(MarkRare, value); }
        public bool RibbonMarkRowdy { get => this.GetRibbonIndex(MarkRowdy); set => this.SetRibbonIndex(MarkRowdy, value); }
        public bool RibbonMarkAbsentMinded { get => this.GetRibbonIndex(MarkAbsentMinded); set => this.SetRibbonIndex(MarkAbsentMinded, value); }
        public bool RibbonMarkJittery { get => this.GetRibbonIndex(MarkJittery); set => this.SetRibbonIndex(MarkJittery, value); }
        public bool RibbonMarkExcited { get => this.GetRibbonIndex(MarkExcited); set => this.SetRibbonIndex(MarkExcited, value); }
        public bool RibbonMarkCharismatic { get => this.GetRibbonIndex(MarkCharismatic); set => this.SetRibbonIndex(MarkCharismatic, value); }
        public bool RibbonMarkCalmness { get => this.GetRibbonIndex(MarkCalmness); set => this.SetRibbonIndex(MarkCalmness, value); }
        public bool RibbonMarkIntense { get => this.GetRibbonIndex(MarkIntense); set => this.SetRibbonIndex(MarkIntense, value); }
        public bool RibbonMarkZonedOut { get => this.GetRibbonIndex(MarkZonedOut); set => this.SetRibbonIndex(MarkZonedOut, value); }
        public bool RibbonMarkJoyful { get => this.GetRibbonIndex(MarkJoyful); set => this.SetRibbonIndex(MarkJoyful, value); }
        public bool RibbonMarkAngry { get => this.GetRibbonIndex(MarkAngry); set => this.SetRibbonIndex(MarkAngry, value); }
        public bool RibbonMarkSmiley { get => this.GetRibbonIndex(MarkSmiley); set => this.SetRibbonIndex(MarkSmiley, value); }
        public bool RibbonMarkTeary { get => this.GetRibbonIndex(MarkTeary); set => this.SetRibbonIndex(MarkTeary, value); }
        public bool RibbonMarkUpbeat { get => this.GetRibbonIndex(MarkUpbeat); set => this.SetRibbonIndex(MarkUpbeat, value); }
        public bool RibbonMarkPeeved { get => this.GetRibbonIndex(MarkPeeved); set => this.SetRibbonIndex(MarkPeeved, value); }
        public bool RibbonMarkIntellectual { get => this.GetRibbonIndex(MarkIntellectual); set => this.SetRibbonIndex(MarkIntellectual, value); }
        public bool RibbonMarkFerocious { get => this.GetRibbonIndex(MarkFerocious); set => this.SetRibbonIndex(MarkFerocious, value); }
        public bool RibbonMarkCrafty { get => this.GetRibbonIndex(MarkCrafty); set => this.SetRibbonIndex(MarkCrafty, value); }
        public bool RibbonMarkScowling { get => this.GetRibbonIndex(MarkScowling); set => this.SetRibbonIndex(MarkScowling, value); }
        public bool RibbonMarkKindly { get => this.GetRibbonIndex(MarkKindly); set => this.SetRibbonIndex(MarkKindly, value); }
        public bool RibbonMarkFlustered { get => this.GetRibbonIndex(MarkFlustered); set => this.SetRibbonIndex(MarkFlustered, value); }
        public bool RibbonMarkPumpedUp { get => this.GetRibbonIndex(MarkPumpedUp); set => this.SetRibbonIndex(MarkPumpedUp, value); }
        public bool RibbonMarkZeroEnergy { get => this.GetRibbonIndex(MarkZeroEnergy); set => this.SetRibbonIndex(MarkZeroEnergy, value); }
        public bool RibbonMarkPrideful { get => this.GetRibbonIndex(MarkPrideful); set => this.SetRibbonIndex(MarkPrideful, value); }
        public bool RibbonMarkUnsure { get => this.GetRibbonIndex(MarkUnsure); set => this.SetRibbonIndex(MarkUnsure, value); }
        public bool RibbonMarkHumble { get => this.GetRibbonIndex(MarkHumble); set => this.SetRibbonIndex(MarkHumble, value); }
        public bool RibbonMarkThorny { get => this.GetRibbonIndex(MarkThorny); set => this.SetRibbonIndex(MarkThorny, value); }
        public bool RibbonMarkVigor { get => this.GetRibbonIndex(MarkVigor); set => this.SetRibbonIndex(MarkVigor, value); }
        public bool RibbonMarkSlump { get => this.GetRibbonIndex(MarkSlump); set => this.SetRibbonIndex(MarkSlump, value); }
        public bool RibbonTwinklingStar { get => this.GetRibbonIndex(TwinklingStar); set => this.SetRibbonIndex(TwinklingStar, value); }
        public bool RibbonPioneer { get => this.GetRibbonIndex(Pioneer); set => this.SetRibbonIndex(Pioneer, value); }

        public int GetRibbonByte(int index) => Array.FindIndex(Data, RibbonBytesOffset, RibbonBytesCount, z => z == index);
        public bool GetRibbon(int index) => GetRibbonByte(index) >= 0;

        public void SetRibbon(int index, bool value = true)
        {
            if ((uint)index > (uint)MarkSlump)
                throw new ArgumentOutOfRangeException(nameof(index));

            if (value)
            {
                if (GetRibbon(index))
                    return;
                var openIndex = Array.FindIndex(Data, RibbonBytesOffset, RibbonBytesCount, z => z != RibbonByteNone);
                if (openIndex < 0)
                    throw new ArgumentOutOfRangeException(nameof(index));
                SetRibbonAtIndex(openIndex, (byte)index);
            }
            else
            {
                var ofs = GetRibbonByte(index);
                if (ofs < 0)
                    return;
                SetRibbonAtIndex(ofs, RibbonByteNone);
            }
        }
        #endregion
    }
}