using System;
using System.Linq;
using static PKHeX.Core.PokeCrypto;
using static System.Buffers.Binary.BinaryPrimitives;
using static PKHeX.Core.EntityFormatDetected;
namespace PKHeX.Core;
public static class EntityFormat
{
///
/// Gets the generation of the Pokemon data.
///
/// Raw data representing a Pokemon.
/// An integer indicating the generation of the PKM file, or -1 if the data is invalid.
public static EntityFormatDetected GetFormat(ReadOnlySpan data)
{
if (!PKX.IsPKM(data.Length))
return None;
return GetFormatInternal(data);
}
private static EntityFormatDetected GetFormatInternal(ReadOnlySpan data) => data.Length switch
{
SIZE_1JLIST or SIZE_1ULIST => FormatPK1,
SIZE_2JLIST or SIZE_2ULIST => FormatPK2,
SIZE_2STADIUM => FormatSK2,
SIZE_3PARTY or SIZE_3STORED => FormatPK3,
SIZE_3CSTORED => FormatCK3,
SIZE_3XSTORED => FormatXK3,
SIZE_4PARTY or SIZE_4STORED => GetFormat45(data),
SIZE_5PARTY => FormatPK5,
SIZE_6STORED => GetFormat67(data),
SIZE_6PARTY => GetFormat67_PGT(data),
SIZE_8PARTY or SIZE_8STORED => GetFormat8(data),
SIZE_8APARTY or SIZE_8ASTORED => FormatPA8,
_ => None,
};
private static EntityFormatDetected GetFormat67_PGT(ReadOnlySpan data)
{
if (!IsFormat67(data))
return None; // PGT collision, same size.
return GetFormat67(data);
}
private static bool IsFormat67(ReadOnlySpan data)
{
if (ReadUInt16LittleEndian(data[0x04..]) != 0) // Bad Sanity?
return false; // non-zero ItemID
if (ReadUInt16LittleEndian(data[0x06..]) == GetCHK(data, SIZE_6STORED))
return true;
if (ReadUInt16LittleEndian(data[0x58..]) != 0) // Not encrypted terminator
return false;
// PGT files have the last 0x10 bytes 00; PK6/etc will have data here.
var tail = data[..^0x10];
foreach (var b in tail)
{
if (b != 0)
return true;
}
return false;
}
// assumes decrypted state
private static EntityFormatDetected GetFormat45(ReadOnlySpan data)
{
if (ReadUInt16LittleEndian(data[0x4..]) != 0)
return FormatBK4; // BK4 non-zero sanity
if (data[0x5F] < 0x10 && ReadUInt16LittleEndian(data[0x80..]) < 0x3333)
return FormatPK4; // gen3/4 version origin, not Transporter
if (ReadUInt16LittleEndian(data[0x46..]) != 0)
return FormatPK4; // PK4.Met_LocationExtended (unused in PK5)
return FormatPK5;
}
///
/// Checks if the input PK6 file is really a PK7, if so, updates the object.
///
/// Updated PKM if actually PK7
private static EntityFormatDetected GetFormat67(ReadOnlySpan data)
{
var pk = new PK6(data.ToArray());
return IsFormatReally7(pk);
}
// assumes decrypted state
private static EntityFormatDetected GetFormat8(ReadOnlySpan data)
{
if (data[0xDE] is (byte)GameVersion.BD or (byte)GameVersion.SP)
return FormatPB8;
return FormatPK8;
}
///
/// Creates an instance of from the given data.
///
/// Raw data of the Pokemon file.
/// Optional identifier for the preferred generation. Usually the generation of the destination save file.
/// An instance of created from the given , or null if is invalid.
public static PKM? GetFromBytes(byte[] data, int prefer = 7)
{
var format = GetFormat(data);
return GetFromBytes(data, format, prefer);
}
private static PKM? GetFromBytes(byte[] data, EntityFormatDetected format, int prefer) => format switch
{
FormatPK1 => new PokeList1(data)[0],
FormatPK2 => new PokeList2(data)[0],
FormatSK2 => new SK2(data),
FormatPK3 => new PK3(data),
FormatCK3 => new CK3(data),
FormatXK3 => new XK3(data),
FormatPK4 => new PK4(data),
FormatBK4 => new BK4(data),
FormatPK5 => new PK5(data),
FormatPK6 => new PK6(data),
FormatPK7 => new PK7(data),
FormatPB7 => new PB7(data),
FormatPK8 => new PK8(data),
FormatPA8 => new PA8(data),
FormatPB8 => new PB8(data),
Format6or7 => prefer == 6 ? new PK6(data) : new PK7(data),
_ => null,
};
///
/// Checks if the input PK6 file is really a PK7.
///
/// PK6 to check
/// Boolean is a PK7
private static EntityFormatDetected IsFormatReally7(PK6 pk)
{
if (pk.Version > Legal.MaxGameID_6)
{
if (pk.Version is ((int)GameVersion.GP or (int)GameVersion.GE))
return FormatPB7;
return FormatPK7;
}
// Check Ranges
if (pk.Species > Legal.MaxSpeciesID_6)
return FormatPK7;
if (pk.Moves.Any(move => move > Legal.MaxMoveID_6_AO))
return FormatPK7;
if (pk.RelearnMoves.Any(move => move > Legal.MaxMoveID_6_AO))
return FormatPK7;
if (pk.Ability > Legal.MaxAbilityID_6_AO)
return FormatPK7;
if (pk.HeldItem > Legal.MaxItemID_6_AO)
return FormatPK7;
// Ground Tile property is replaced with Hyper Training PK6->PK7
var et = pk.GroundTile;
if (et != 0)
{
if (pk.CurrentLevel < 100) // can't be hyper trained
return FormatPK6;
if (!pk.Gen4) // can't have GroundTile
return FormatPK7;
if (et > GroundTileType.Max_Pt) // invalid gen4 GroundTile
return FormatPK7;
}
int mb = ReadUInt16LittleEndian(pk.Data.AsSpan(0x16));
if (mb > 0xAAA)
return FormatPK6;
for (int i = 0; i < 6; i++)
{
if ((mb >> (i << 1) & 3) == 3) // markings are 10 or 01 (or 00), never 11
return FormatPK6;
}
if (pk.Data[0x2A] > 20) // ResortEventStatus is always < 20
return FormatPK6;
return Format6or7;
}
}
public enum EntityFormatDetected
{
None = -1,
FormatPK1,
FormatPK2, FormatSK2,
FormatPK3, FormatCK3, FormatXK3,
FormatPK4, FormatBK4, FormatPK5,
FormatPK6, FormatPK7, FormatPB7,
FormatPK8, FormatPA8, FormatPB8,
Format6or7,
}