PKHeX/PKHeX.Core/PKM/HOME/GameDataPK9.cs

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

namespace PKHeX.Core;

/// <summary>
/// Side game data for <see cref="PK9"/> data transferred into HOME.
/// </summary>
public sealed class GameDataPK9 : HomeOptional1, IGameDataSide
{
    private const HomeGameDataFormat ExpectFormat = HomeGameDataFormat.PK9;
    private const int SIZE = HomeCrypto.SIZE_1GAME_PK9;
    protected override HomeGameDataFormat Format => ExpectFormat;

    public GameDataPK9() : base(SIZE) { }
    public GameDataPK9(Memory<byte> data) : base(data) => EnsureSize(SIZE);
    public GameDataPK9 Clone() => new(ToArray());
    public int WriteTo(Span<byte> result) => WriteWithHeader(result);

    #region Structure

    public ushort Move1 { get => ReadUInt16LittleEndian(Data); set => WriteUInt16LittleEndian(Data, value); }
    public ushort Move2 { get => ReadUInt16LittleEndian(Data[0x02..]); set => WriteUInt16LittleEndian(Data[0x02..], value); }
    public ushort Move3 { get => ReadUInt16LittleEndian(Data[0x04..]); set => WriteUInt16LittleEndian(Data[0x04..], value); }
    public ushort Move4 { get => ReadUInt16LittleEndian(Data[0x06..]); set => WriteUInt16LittleEndian(Data[0x06..], value); }

    public int Move1_PP    { get => Data[0x08]; set => Data[0x08] = (byte)value; }
    public int Move2_PP    { get => Data[0x09]; set => Data[0x09] = (byte)value; }
    public int Move3_PP    { get => Data[0x0A]; set => Data[0x0A] = (byte)value; }
    public int Move4_PP    { get => Data[0x0B]; set => Data[0x0B] = (byte)value; }
    public int Move1_PPUps { get => Data[0x0C]; set => Data[0x0C] = (byte)value; }
    public int Move2_PPUps { get => Data[0x0D]; set => Data[0x0D] = (byte)value; }
    public int Move3_PPUps { get => Data[0x0E]; set => Data[0x0E] = (byte)value; }
    public int Move4_PPUps { get => Data[0x0F]; set => Data[0x0F] = (byte)value; }

    public ushort RelearnMove1 { get => ReadUInt16LittleEndian(Data[0x10..]); set => WriteUInt16LittleEndian(Data[0x10..], value); }
    public ushort RelearnMove2 { get => ReadUInt16LittleEndian(Data[0x12..]); set => WriteUInt16LittleEndian(Data[0x12..], value); }
    public ushort RelearnMove3 { get => ReadUInt16LittleEndian(Data[0x14..]); set => WriteUInt16LittleEndian(Data[0x14..], value); }
    public ushort RelearnMove4 { get => ReadUInt16LittleEndian(Data[0x16..]); set => WriteUInt16LittleEndian(Data[0x16..], value); }
    public int Egg_Location { get => ReadUInt16LittleEndian(Data[0x18..]); set => WriteUInt16LittleEndian(Data[0x18..], (ushort)value); }
    public int Met_Location { get => ReadUInt16LittleEndian(Data[0x1A..]); set => WriteUInt16LittleEndian(Data[0x1A..], (ushort)value); }

    public int Ball { get => Data[0x1C]; set => Data[0x1C] = (byte)value; }
    public byte Scale { get => Data[0x1D]; set => Data[0x1D] = value; }
    public MoveType TeraTypeOriginal { get => (MoveType)Data[0x1E]; set => Data[0x1E] = (byte)value; }
    public MoveType TeraTypeModified { get => (MoveType)Data[0x1F]; set => Data[0x1F] = (byte)value; }

    private const int RecordStart = 0x20;
    private const int RecordCount = PK9.COUNT_RECORD; // Up to 200 TM flags, but not all are used.
    private const int RecordLength = RecordCount / 8;
    private Span<byte> RecordFlags => Data.Slice(RecordStart, RecordLength);

    public bool GetMoveRecordFlag(int index)
    {
        if ((uint)index > RecordCount) // 0x19 bytes, 8 bits
            throw new ArgumentOutOfRangeException(nameof(index));
        return FlagUtil.GetFlag(RecordFlags, index >> 3, index & 7);
    }

    public void SetMoveRecordFlag(int index, bool value = true)
    {
        if ((uint)index > RecordCount) // 0x19 bytes, 8 bits
            throw new ArgumentOutOfRangeException(nameof(index));
        FlagUtil.SetFlag(RecordFlags, index >> 3, index & 7, value);
    }

    public bool GetMoveRecordFlagAny() => RecordFlags.IndexOfAnyExcept<byte>(0) >= 0;
    public void ClearMoveRecordFlags() => RecordFlags.Clear();

    #endregion

    #region Conversion

    public PersonalInfo GetPersonalInfo(ushort species, byte form) => PersonalTable.SV.GetFormEntry(species, form);

    public void CopyTo(PK9 pk)
    {
        ((IGameDataSide)this).CopyTo(pk);
        pk.Scale = Scale;
        pk.TeraTypeOriginal = TeraTypeOriginal;
        pk.TeraTypeOverride = TeraTypeModified;
        RecordFlags.CopyTo(pk.RecordFlags);
    }

    public PKM ConvertToPKM(PKH pkh) => ConvertToPK9(pkh);

    public PK9 ConvertToPK9(PKH pkh)
    {
        var pk = new PK9();
        pkh.CopyTo(pk);
        CopyTo(pk);
        return pk;
    }

    #endregion

    /// <summary> Reconstructive logic to best apply suggested values. </summary>
    public static GameDataPK9? TryCreate(PKH pkh)
    {
        if (!PersonalTable.SV.IsPresentInGame(pkh.Species, pkh.Form))
            return null;

        if (pkh.DataPB7 is { } x)
            return Create(x);
        if (pkh.DataPK8 is { } b)
            return Create(b);
        if (pkh.DataPA8 is { } a)
            return Create(a);
        if (pkh.DataPB8 is { } bd)
            return Create(bd);
        return null;
    }

    public static T Create<T>(GameDataPK9 data) where T : IGameDataSide, new() => new()
    {
        Ball = data.Ball,
        Met_Location = data.Met_Location == Locations.Default8bNone ? 0 : data.Met_Location,
        Egg_Location = data.Egg_Location == Locations.Default8bNone ? 0 : data.Egg_Location,
    };

    public static GameDataPK9 Create(IGameDataSide data) => new()
    {
        Ball = data.Ball,
        Met_Location = data.Met_Location == 0 ? Locations.Default8bNone : data.Met_Location,
        Egg_Location = data.Egg_Location == 0 ? Locations.Default8bNone : data.Egg_Location,
    };
}