using System;
using static System.Buffers.Binary.BinaryPrimitives;

namespace pkNX.Structures;

/// <summary>
/// Personal Info class with values from the <see cref="GameVersion.SWSH"/> games.
/// </summary>
public sealed class PersonalInfo8SWSH : IPersonalInfoSWSH
{
    public const int SIZE = 0xB0;
    public const int CountTM = 128;
    public const int CountTR = 128;
    private readonly byte[] Data;

    public bool[] TMHM { get; set; }
    public bool[] TR { get; set; }
    public bool[] TypeTutors { get; set; }
    public bool[] SpecialTutors { get; set; }

    public PersonalInfo8SWSH(ReadOnlySpan<byte> data)
    {
        Data = data.ToArray();
        DexIndexNational = ModelID;

        TMHM = new bool[CountTM];
        TR = new bool[CountTR];
        FlagUtil.GetFlagArray(data[0x28..], TMHM.AsSpan(0, CountTM));
        FlagUtil.GetFlagArray(data[0x3C..], TR.AsSpan(0, CountTR));

        // 0x38-0x3B type tutors, but only 8 bits are valid flags.
        TypeTutors = new bool[32];
        FlagUtil.GetFlagArray(data[0x38..], TypeTutors);

        // 0xA8-0xAC are armor type tutors, one bit for each type
        var armor = new bool[32];
        FlagUtil.GetFlagArray(data[0xA8..], armor);
        SpecialTutors = armor;
    }

    public byte[] Write()
    {
        Span<byte> data = Data;
        FlagUtil.SetFlagArray(data[0x28..], TMHM.AsSpan(0, CountTM));
        FlagUtil.SetFlagArray(data[0x38..], TypeTutors);
        FlagUtil.SetFlagArray(data[0x3C..], TR.AsSpan(0, CountTR));
        FlagUtil.SetFlagArray(data[0xA8..], SpecialTutors);
        return Data;
    }

    public int HP { get => Data[0x00]; set => Data[0x00] = (byte)value; }
    public int ATK { get => Data[0x01]; set => Data[0x01] = (byte)value; }
    public int DEF { get => Data[0x02]; set => Data[0x02] = (byte)value; }
    public int SPE { get => Data[0x03]; set => Data[0x03] = (byte)value; }
    public int SPA { get => Data[0x04]; set => Data[0x04] = (byte)value; }
    public int SPD { get => Data[0x05]; set => Data[0x05] = (byte)value; }
    public Types Type1 { get => (Types)Data[0x06]; set => Data[0x06] = (byte)value; }
    public Types Type2 { get => (Types)Data[0x07]; set => Data[0x07] = (byte)value; }
    public int CatchRate { get => Data[0x08]; set => Data[0x08] = (byte)value; }
    public int EvoStage { get => Data[0x09]; set => Data[0x09] = (byte)value; }
    private int EVYield { get => ReadUInt16LittleEndian(Data.AsSpan(0x0A)); set => WriteUInt16LittleEndian(Data.AsSpan(0x0A), (ushort)value); }
    public int EV_HP { get => (EVYield >> 0) & 0x3; set => EVYield = (EVYield & ~(0x3 << 0)) | ((value & 0x3) << 0); }
    public int EV_ATK { get => (EVYield >> 2) & 0x3; set => EVYield = (EVYield & ~(0x3 << 2)) | ((value & 0x3) << 2); }
    public int EV_DEF { get => (EVYield >> 4) & 0x3; set => EVYield = (EVYield & ~(0x3 << 4)) | ((value & 0x3) << 4); }
    public int EV_SPE { get => (EVYield >> 6) & 0x3; set => EVYield = (EVYield & ~(0x3 << 6)) | ((value & 0x3) << 6); }
    public int EV_SPA { get => (EVYield >> 8) & 0x3; set => EVYield = (EVYield & ~(0x3 << 8)) | ((value & 0x3) << 8); }
    public int EV_SPD { get => (EVYield >> 10) & 0x3; set => EVYield = (EVYield & ~(0x3 << 10)) | ((value & 0x3) << 10); }
    public int Item1 { get => ReadInt16LittleEndian(Data.AsSpan(0x0C)); set => WriteInt16LittleEndian(Data.AsSpan(0x0C), (short)value); }
    public int Item2 { get => ReadInt16LittleEndian(Data.AsSpan(0x0E)); set => WriteInt16LittleEndian(Data.AsSpan(0x0E), (short)value); }
    public int Item3 { get => ReadInt16LittleEndian(Data.AsSpan(0x10)); set => WriteInt16LittleEndian(Data.AsSpan(0x10), (short)value); }
    public int Gender { get => Data[0x12]; set => Data[0x12] = (byte)value; }
    public byte HatchCycles { get => Data[0x13]; set => Data[0x13] = value; }
    public int BaseFriendship { get => Data[0x14]; set => Data[0x14] = (byte)value; }
    public int EXPGrowth { get => Data[0x15]; set => Data[0x15] = (byte)value; }
    public int EggGroup1 { get => Data[0x16]; set => Data[0x16] = (byte)value; }
    public int EggGroup2 { get => Data[0x17]; set => Data[0x17] = (byte)value; }
    public int Ability1 { get => ReadUInt16LittleEndian(Data.AsSpan(0x18)); set => WriteUInt16LittleEndian(Data.AsSpan(0x18), (ushort)value); }
    public int Ability2 { get => ReadUInt16LittleEndian(Data.AsSpan(0x1A)); set => WriteUInt16LittleEndian(Data.AsSpan(0x1A), (ushort)value); }
    public int AbilityH { get => ReadUInt16LittleEndian(Data.AsSpan(0x1C)); set => WriteUInt16LittleEndian(Data.AsSpan(0x1C), (ushort)value); }
    public int EscapeRate { get => 0; set { } } // moved?
    public int FormStatsIndex { get => ReadUInt16LittleEndian(Data.AsSpan(0x1E)); set => WriteUInt16LittleEndian(Data.AsSpan(0x1E), (ushort)value); }
    public int FormSprite { get => FormStatsIndex; set => FormStatsIndex = value; }
    public byte FormCount { get => Data[0x20]; set => Data[0x20] = value; }
    public int Color { get => Data[0x21] & 0x3F; set => Data[0x21] = (byte)((Data[0x21] & 0xC0) | (value & 0x3F)); }
    public bool IsPresentInGame { get => ((Data[0x21] >> 6) & 1) == 1; set => Data[0x21] = (byte)((Data[0x21] & ~0x40) | (value ? 0x40 : 0)); }
    public bool SpriteForm { get => ((Data[0x21] >> 7) & 1) == 1; set => Data[0x21] = (byte)((Data[0x21] & ~0x80) | (value ? 0x80 : 0)); }
    public int BaseEXP { get => ReadUInt16LittleEndian(Data.AsSpan(0x22)); set => WriteUInt16LittleEndian(Data.AsSpan(0x22), (ushort)value); }
    public int Height { get => ReadUInt16LittleEndian(Data.AsSpan(0x24)); set => WriteUInt16LittleEndian(Data.AsSpan(0x24), (ushort)value); }
    public int Weight { get => ReadUInt16LittleEndian(Data.AsSpan(0x26)); set => WriteUInt16LittleEndian(Data.AsSpan(0x26), (ushort)value); }

    // 0x28-0x37 TM
    // 0x38-0x3B type tutors, but only 8 bits are valid flags.
    // 0x3C-0x4B TR

    public ushort ModelID { get => (ushort)ReadUInt32LittleEndian(Data.AsSpan(0x4C)); set => WriteUInt32LittleEndian(Data.AsSpan(0x4C), value); } // Model ID

    public ushort ZItem { get => ReadUInt16LittleEndian(Data.AsSpan(0x50)); set => WriteUInt16LittleEndian(Data.AsSpan(0x50), value); }
    public ushort ZBaseMove { get => ReadUInt16LittleEndian(Data.AsSpan(0x52)); set => WriteUInt16LittleEndian(Data.AsSpan(0x52), value); }
    public ushort ZSpecialMove { get => ReadUInt16LittleEndian(Data.AsSpan(0x54)); set => WriteUInt16LittleEndian(Data.AsSpan(0x54), value); }

    public ushort HatchedSpecies { get => ReadUInt16LittleEndian(Data.AsSpan(0x56)); set => WriteUInt16LittleEndian(Data.AsSpan(0x56), value); }
    public ushort LocalFormIndex { get => ReadUInt16LittleEndian(Data.AsSpan(0x58)); set => WriteUInt16LittleEndian(Data.AsSpan(0x58), value); } // local region base form
    public ushort RegionalFlags { get => ReadUInt16LittleEndian(Data.AsSpan(0x5A)); set => WriteUInt16LittleEndian(Data.AsSpan(0x5A), value); }
    public bool IsRegionalForm { get => (RegionalFlags & 1) == 1; set => RegionalFlags = (ushort)((RegionalFlags & 0xFFFE) | (value ? 1 : 0)); }
    public bool CanNotDynamax { get => ((Data[0x5A] >> 2) & 1) == 1; set => Data[0x5A] = (byte)((Data[0x5A] & ~4) | (value ? 4 : 0)); }
    public ushort DexIndexRegional { get => ReadUInt16LittleEndian(Data.AsSpan(0x5C)); set => WriteUInt16LittleEndian(Data.AsSpan(0x5C), value); }
    public ushort Form { get => (byte)ReadUInt16LittleEndian(Data.AsSpan(0x5E)); set => WriteUInt16LittleEndian(Data.AsSpan(0x5E), value); } // form index of this entry

    public ushort Quantized_floats_0 { get => ReadUInt16LittleEndian(Data.AsSpan(0x60)); set => WriteUInt16LittleEndian(Data.AsSpan(0x60), value); }
    public ushort Quantized_floats_1 { get => ReadUInt16LittleEndian(Data.AsSpan(0x62)); set => WriteUInt16LittleEndian(Data.AsSpan(0x62), value); }
    public ushort Quantized_floats_2 { get => ReadUInt16LittleEndian(Data.AsSpan(0x64)); set => WriteUInt16LittleEndian(Data.AsSpan(0x64), value); }
    public ushort Quantized_floats_3 { get => ReadUInt16LittleEndian(Data.AsSpan(0x66)); set => WriteUInt16LittleEndian(Data.AsSpan(0x66), value); }
    public ushort Quantized_floats_4 { get => ReadUInt16LittleEndian(Data.AsSpan(0x68)); set => WriteUInt16LittleEndian(Data.AsSpan(0x68), value); }

    public Span<byte> GetUnknownByteSet(int index) => index switch
    {
        0 => Data.AsSpan(0x6A, 10),
        1 => Data.AsSpan(0x74, 10),
        2 => Data.AsSpan(0x7E, 5),
        3 => Data.AsSpan(0x83, 5),
        4 => Data.AsSpan(0x88, 5),
        5 => Data.AsSpan(0x8D, 5),
        _ => throw new ArgumentOutOfRangeException(nameof(index)),
    };

    public ushort Shorts_0 { get => ReadUInt16LittleEndian(Data.AsSpan(0x92)); set => WriteUInt16LittleEndian(Data.AsSpan(0x92), value); }
    public ushort Shorts_1 { get => ReadUInt16LittleEndian(Data.AsSpan(0x94)); set => WriteUInt16LittleEndian(Data.AsSpan(0x94), value); }
    public ushort Shorts_2 { get => ReadUInt16LittleEndian(Data.AsSpan(0x96)); set => WriteUInt16LittleEndian(Data.AsSpan(0x96), value); }
    public ushort Shorts_3 { get => ReadUInt16LittleEndian(Data.AsSpan(0x98)); set => WriteUInt16LittleEndian(Data.AsSpan(0x98), value); }
    public ushort Shorts_4 { get => ReadUInt16LittleEndian(Data.AsSpan(0x9A)); set => WriteUInt16LittleEndian(Data.AsSpan(0x9A), value); }
    public ushort Shorts_5 { get => ReadUInt16LittleEndian(Data.AsSpan(0x9C)); set => WriteUInt16LittleEndian(Data.AsSpan(0x9C), value); }
    public ushort Shorts_6 { get => ReadUInt16LittleEndian(Data.AsSpan(0x9E)); set => WriteUInt16LittleEndian(Data.AsSpan(0x9E), value); }
    public ushort Shorts_7 { get => ReadUInt16LittleEndian(Data.AsSpan(0xA0)); set => WriteUInt16LittleEndian(Data.AsSpan(0xA0), value); }
    public ushort Shorts_8 { get => ReadUInt16LittleEndian(Data.AsSpan(0xA2)); set => WriteUInt16LittleEndian(Data.AsSpan(0xA2), value); }
    public ushort Shorts_9 { get => ReadUInt16LittleEndian(Data.AsSpan(0xA4)); set => WriteUInt16LittleEndian(Data.AsSpan(0xA4), value); }

    public ushort Reserved { get => ReadUInt16LittleEndian(Data.AsSpan(0xA6)); set => WriteUInt16LittleEndian(Data.AsSpan(0xA6), value); }

    // 0xA8-0xAB are armor type tutors, one bit for each type
    public ushort ArmorDexIndex { get => ReadUInt16LittleEndian(Data.AsSpan(0xAC)); set => WriteUInt16LittleEndian(Data.AsSpan(0xAC), value); }
    public ushort CrownDexIndex { get => ReadUInt16LittleEndian(Data.AsSpan(0xAE)); set => WriteUInt16LittleEndian(Data.AsSpan(0xAE), value); }

    public ushort DexIndexNational { get; set; }

    /// <summary>
    /// Gets the Form that any offspring will hatch with, assuming it is holding an Everstone.
    /// </summary>
    public byte HatchFormIndexEverstone => IsRegionalForm ? (byte)Form : (byte)LocalFormIndex;

    /// <summary>
    /// Checks if the entry shows up in any of the built-in Pokédex.
    /// </summary>
    public bool IsInDex => DexIndexRegional != 0 || ArmorDexIndex != 0 || CrownDexIndex != 0;
}
