PKHeX/PKHeX.Core/Legality/RNG/MethodFinder.cs
Kurt d5e5a463dc Refactor order of pidiv checks
collision between mgshiny and cutecharm shinies
Closes #1435
2017-08-29 08:32:22 -07:00

682 lines
27 KiB
C#

using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Runtime.CompilerServices;
namespace PKHeX.Core
{
/// <summary>
/// Class containing logic to obtain a PKM's PIDIV method.
/// </summary>
public static class MethodFinder
{
/// <summary>
/// Analyzes a <see cref="PKM"/> to find a matching PIDIV method.
/// </summary>
/// <param name="pk">Input <see cref="PKM"/>.</param>
/// <returns><see cref="PIDIV"/> object containing seed and method info.</returns>
public static PIDIV Analyze(PKM pk)
{
if (pk.Format < 3)
return AnalyzeGB(pk);
var pid = pk.EncryptionConstant;
var top = pid >> 16;
var bot = pid & 0xFFFF;
var iIVs = pk.IVs;
var IVs = new uint[6];
for (int i = 0; i < 6; i++)
IVs[i] = (uint)iIVs[i];
PIDIV pidiv;
if (GetLCRNGMatch(top, bot, IVs, out pidiv))
return pidiv;
if (pk.Species == 201 && GetLCRNGUnownMatch(top, bot, IVs, out pidiv)) // frlg only
return pidiv;
if (GetXDRNGMatch(top, bot, IVs, out pidiv))
return pidiv;
// Special cases
if (GetLCRNGRoamerMatch(top, bot, IVs, out pidiv))
return pidiv;
if (GetChannelMatch(top, bot, IVs, out pidiv, pk))
return pidiv;
if (GetMG4Match(pid, IVs, out pidiv))
return pidiv;
if (GetBACDMatch(pk, pid, IVs, out pidiv))
return pidiv;
if (GetModifiedPIDMatch(pk, pid, IVs, out pidiv))
return pidiv;
return new PIDIV {Type=PIDType.None, NoSeed=true}; // no match
}
private static bool GetModifiedPIDMatch(PKM pk, uint pid, uint[] IVs, out PIDIV pidiv)
{
if (pk.IsShiny)
{
if (GetChainShinyMatch(pk, pid, IVs, out pidiv))
return true;
if (GetModified8BitMatch(pk, pid, out pidiv))
return true;
}
else
{
if (pid <= 0xFF && GetCuteCharmMatch(pk, pid, out pidiv))
return true;
}
return GetPokewalkerMatch(pk, pid, out pidiv);
}
private static bool GetModified8BitMatch(PKM pk, uint pid, out PIDIV pidiv)
{
return pk.GenNumber == 4
? pid <= 0xFF && GetCuteCharmMatch(pk, pid, out pidiv) || GetG5MGShinyMatch(pk, pid, out pidiv)
: GetG5MGShinyMatch(pk, pid, out pidiv) || pid <= 0xFF && GetCuteCharmMatch(pk, pid, out pidiv);
}
private static bool GetLCRNGMatch(uint top, uint bot, uint[] IVs, out PIDIV pidiv)
{
var reg = GetSeedsFromPID(RNG.LCRNG, top, bot);
var iv1 = GetIVChunk(IVs, 0);
var iv2 = GetIVChunk(IVs, 3);
foreach (var seed in reg)
{
// A and B are already used by PID
var B = RNG.LCRNG.Advance(seed, 2);
// Method 1/2/4 can use 3 different RNG frames
var C = RNG.LCRNG.Next(B);
var ivC = C >> 16 & 0x7FFF;
if (iv1 == ivC)
{
var D = RNG.LCRNG.Next(C);
var ivD = D >> 16 & 0x7FFF;
if (iv2 == ivD) // ABCD
{
pidiv = new PIDIV {OriginSeed = seed, RNG = RNG.LCRNG, Type = PIDType.Method_1};
return true;
}
var E = RNG.LCRNG.Next(D);
var ivE = E >> 16 & 0x7FFF;
if (iv2 == ivE) // ABCE
{
pidiv = new PIDIV {OriginSeed = seed, RNG = RNG.LCRNG, Type = PIDType.Method_4};
return true;
}
}
else
{
var D = RNG.LCRNG.Next(C);
var ivD = D >> 16 & 0x7FFF;
if (iv1 != ivD)
continue;
var E = RNG.LCRNG.Next(D);
var ivE = E >> 16 & 0x7FFF;
if (iv2 == ivE) // ABDE
{
pidiv = new PIDIV {OriginSeed = seed, RNG = RNG.LCRNG, Type = PIDType.Method_2};
return true;
}
}
}
return GetNonMatch(out pidiv);
}
private static bool GetLCRNGUnownMatch(uint top, uint bot, uint[] IVs, out PIDIV pidiv)
{
// this is an exact copy of LCRNG 1,2,4 matching, except the PID has its halves switched (BACD, BADE, BACE)
var reg = GetSeedsFromPID(RNG.LCRNG, bot, top); // reversed!
var iv1 = GetIVChunk(IVs, 0);
var iv2 = GetIVChunk(IVs, 3);
foreach (var seed in reg)
{
// A and B are already used by PID
var B = RNG.LCRNG.Advance(seed, 2);
// Method 1/2/4 can use 3 different RNG frames
var C = RNG.LCRNG.Next(B);
var ivC = C >> 16 & 0x7FFF;
if (iv1 == ivC)
{
var D = RNG.LCRNG.Next(C);
var ivD = D >> 16 & 0x7FFF;
if (iv2 == ivD) // BACD
{
pidiv = new PIDIV {OriginSeed = seed, RNG = RNG.LCRNG, Type = PIDType.Method_1_Unown};
return true;
}
var E = RNG.LCRNG.Next(D);
var ivE = E >> 16 & 0x7FFF;
if (iv2 == ivE) // BACE
{
pidiv = new PIDIV {OriginSeed = seed, RNG = RNG.LCRNG, Type = PIDType.Method_4_Unown};
return true;
}
}
else
{
var D = RNG.LCRNG.Next(C);
var ivD = D >> 16 & 0x7FFF;
if (iv1 != ivD)
continue;
var E = RNG.LCRNG.Next(D);
var ivE = E >> 16 & 0x7FFF;
if (iv2 == ivE) // BADE
{
pidiv = new PIDIV {OriginSeed = seed, RNG = RNG.LCRNG, Type = PIDType.Method_2_Unown};
return true;
}
}
}
return GetNonMatch(out pidiv);
}
private static bool GetLCRNGRoamerMatch(uint top, uint bot, uint[] IVs, out PIDIV pidiv)
{
if (IVs.Skip(2).Any(iv => iv != 0) || IVs[1] > 7)
return GetNonMatch(out pidiv);
var iv1 = GetIVChunk(IVs, 0);
var reg = GetSeedsFromPID(RNG.LCRNG, top, bot);
foreach (var seed in reg)
{
// Only the first 8 bits are kept
var ivC = RNG.LCRNG.Advance(seed, 3) >> 16 & 0x00FF;
if (iv1 != ivC)
continue;
pidiv = new PIDIV {OriginSeed = seed, RNG = RNG.LCRNG, Type = PIDType.Method_1_Roamer};
return true;
}
return GetNonMatch(out pidiv);
}
private static bool GetXDRNGMatch(uint top, uint bot, uint[] IVs, out PIDIV pidiv)
{
var xdc = GetSeedsFromPIDEuclid(RNG.XDRNG, top, bot);
foreach (var seed in xdc)
{
var B = RNG.XDRNG.Prev(seed);
var A = RNG.XDRNG.Prev(B);
if (!GetIVs(A >> 16, B >> 16).SequenceEqual(IVs))
continue;
pidiv = new PIDIV {OriginSeed = RNG.XDRNG.Prev(A), RNG = RNG.XDRNG, Type = PIDType.CXD};
return true;
}
return GetNonMatch(out pidiv);
}
private static bool GetChannelMatch(uint top, uint bot, uint[] IVs, out PIDIV pidiv, PKM pk)
{
var ver = pk.Version;
if (ver != (int) GameVersion.R && ver != (int) GameVersion.S)
return GetNonMatch(out pidiv);
var undo = top ^ 0x8000;
if ((undo > 7 ? 0 : 1) != (bot ^ pk.SID ^ 40122))
top = undo;
var channel = GetSeedsFromPIDEuclid(RNG.XDRNG, top, bot);
foreach (var seed in channel)
{
var C = RNG.XDRNG.Advance(seed, 3); // held item
// no checks, held item can be swapped
var D = RNG.XDRNG.Next(C); // Version
if ((D >> 31) + 1 != ver) // (0-Sapphire, 1-Ruby)
continue;
var E = RNG.XDRNG.Next(D); // OT Gender
if (E >> 31 != pk.OT_Gender)
continue;
if (!RNG.XDRNG.GetSequentialIVsUInt32(E).SequenceEqual(IVs))
continue;
if (seed >> 16 != pk.SID)
continue;
pidiv = new PIDIV {OriginSeed = RNG.XDRNG.Prev(seed), RNG = RNG.XDRNG, Type = PIDType.Channel};
return true;
}
return GetNonMatch(out pidiv);
}
private static bool GetMG4Match(uint pid, uint[] IVs, out PIDIV pidiv)
{
uint mg4Rev = RNG.ARNG.Prev(pid);
var mg4 = GetSeedsFromPID(RNG.LCRNG, mg4Rev >> 16, mg4Rev & 0xFFFF);
foreach (var seed in mg4)
{
var B = RNG.LCRNG.Advance(seed, 2);
var C = RNG.LCRNG.Next(B);
var D = RNG.LCRNG.Next(C);
if (!GetIVs(C >> 16, D >> 16).SequenceEqual(IVs))
continue;
pidiv = new PIDIV {OriginSeed = seed, RNG = RNG.LCRNG, Type = PIDType.G4MGAntiShiny};
return true;
}
return GetNonMatch(out pidiv);
}
private static bool GetG5MGShinyMatch(PKM pk, uint pid, out PIDIV pidiv)
{
var low = pid & 0xFFFF;
// generation 5 shiny PIDs
if (low <= 0xFF)
{
var high = pid >> 16;
if (((pk.TID ^ pk.SID ^ low) - high & 0xFFFE) == 0)
{
pidiv = new PIDIV {NoSeed = true, Type = PIDType.G5MGShiny};
return true;
}
}
return GetNonMatch(out pidiv);
}
private static bool GetCuteCharmMatch(PKM pk, uint pid, out PIDIV pidiv)
{
if (pid > 0xFF)
return GetNonMatch(out pidiv);
int genderValue = pk.Gender;
switch (genderValue)
{
case 2: break; // can't cute charm a genderless pkm
case 0: // male
var gr = pk.PersonalInfo.Gender;
if (254 <= gr) // no modification for PID
break;
var rate = pk.Gender == 1 ? 0 : 25*(gr/25 + 1); // buffered
var nature = pid % 25;
if (nature + rate != pid)
break;
pidiv = new PIDIV {NoSeed = true, RNG = RNG.LCRNG, Type = PIDType.CuteCharm};
return true;
case 1: // female
if (pid >= 25)
break; // nope
if (254 <= pk.PersonalInfo.Gender) // no modification for PID
break;
pidiv = new PIDIV {NoSeed = true, RNG = RNG.LCRNG, Type = PIDType.CuteCharm};
return true;
}
return GetNonMatch(out pidiv);
}
private static bool GetChainShinyMatch(PKM pk, uint pid, uint[] IVs, out PIDIV pidiv)
{
// 13 shiny bits
// PIDH & 7
// PIDL & 7
// IVs
var bot = GetIVChunk(IVs, 0);
var top = GetIVChunk(IVs, 3);
var reg = GetSeedsFromIVs(RNG.LCRNG, top, bot);
foreach (var seed in reg)
{
// check the individual bits
var s = seed;
int i = 15;
while (true)
{
var bit = s >> 16 & 1;
if (bit != (pid >> i & 1))
break;
s = RNG.LCRNG.Prev(s);
if (--i == 2)
break;
}
if (i != 2) // bit failed
continue;
// Shiny Bits of PID validated
var upper = s;
if ((upper >> 16 & 7) != (pid >> 16 & 7))
continue;
var lower = RNG.LCRNG.Prev(upper);
if ((lower >> 16 & 7) != (pid & 7))
continue;
var upid = ((pid & 0xFFFF) ^ pk.TID ^ pk.SID) & 0xFFF8 | (upper >> 16) & 0x7;
if (upid != pid >> 16)
continue;
s = RNG.LCRNG.Reverse(lower, 2); // unroll one final time to get the origin seed
pidiv = new PIDIV {OriginSeed = s, RNG = RNG.LCRNG, Type = PIDType.ChainShiny};
return true;
}
return GetNonMatch(out pidiv);
}
private static bool GetBACDMatch(PKM pk, uint pid, uint[] IVs, out PIDIV pidiv)
{
var bot = GetIVChunk(IVs, 0);
var top = GetIVChunk(IVs, 3);
var reg = GetSeedsFromIVs(RNG.LCRNG, top, bot);
foreach (var seed in reg)
{
var B = seed;
var A = RNG.LCRNG.Prev(B);
var PID = A & 0xFFFF0000 | B >> 16;
bool isShiny = (pk.TID ^ pk.SID ^ PID >> 16 ^ PID & 0xFFFF) < 8;
bool forceShiny = false;
bool antiShiny = false;
if (PID != pid)
{
if (!isShiny)
{
// check for force shiny pkm
if (!pk.IsShiny)
continue; // obviously not force shiny
// 0-Origin
// 1-PIDH
// 2-PIDL (ends up unused)
// 3-FORCEBITS
// PID = PIDH << 16 | (SID ^ TID ^ PIDH)
var X = RNG.LCRNG.Prev(A);
PID = X & 0xFFFF0000 | (uint)pk.SID ^ (uint)pk.TID ^ X >> 16;
PID &= 0xFFFFFFF8;
PID |= B >> 16 & 0x7; // lowest 3 bits
if (PID != pid)
continue;
forceShiny = true;
}
if (!forceShiny)
{
if ((PID + 8 & 0xFFFFFFF8) != pid)
continue;
antiShiny = true;
}
}
var s = RNG.LCRNG.Prev(A);
// Check for prior Restricted seed
var sn = s;
for (int i = 0; i < 3; i++, sn = RNG.LCRNG.Prev(sn))
{
if ((sn & 0xFFFF0000) != 0)
continue;
var type = forceShiny ? PIDType.BACD_R_S : antiShiny ? PIDType.BACD_R_A : PIDType.BACD_R;
pidiv = new PIDIV {OriginSeed = sn, RNG = RNG.LCRNG, Type = type};
return true;
}
// no restricted seed found, thus unrestricted
var t = forceShiny ? PIDType.BACD_U_S : antiShiny ? PIDType.BACD_U_A : PIDType.BACD_U;
pidiv = new PIDIV {OriginSeed = s, RNG = RNG.LCRNG, Type = t};
return true;
}
return GetNonMatch(out pidiv);
}
private static bool GetPokewalkerMatch(PKM pk, uint oldpid, out PIDIV pidiv)
{
// check surface compatibility
var mid = oldpid & 0x00FFFF00;
if (mid != 0 && mid != 0x00FFFF00) // not expected bits
return GetNonMatch(out pidiv);
var nature = oldpid % 25;
if (nature == 24) // impossible nature
return GetNonMatch(out pidiv);
uint pid = (uint)((pk.TID ^ pk.SID) >> 8 ^ 0xFF) << 24; // the most significant byte of the PID is chosen so the Pokémon can never be shiny.
// Ensure nature is set to required nature without affecting shininess
pid += nature - pid % 25;
// Ensure Gender is set to required gender without affecting other properties
// If Gender is modified, modify the ability if appropriate
int currentGender = pk.Gender;
if (currentGender != 2) // either m/f
{
var gr = pk.PersonalInfo.Gender;
var pidGender = (pid & 0xFF) < gr ? 1 : 0;
if (currentGender != pidGender)
{
if (currentGender == 0) // Male
{
pid += (uint) (((gr - (pid & 0xFF)) / 25 + 1) * 25);
if ((nature & 1) != (pid & 1))
pid += 25;
}
else
{
pid -= (uint) ((((pid & 0xFF) - gr) / 25 + 1) * 25);
if ((nature & 1) != (pid & 1))
pid -= 25;
}
}
}
if (pid != oldpid)
return GetNonMatch(out pidiv);
pidiv = new PIDIV {NoSeed = true, RNG = RNG.LCRNG, Type = PIDType.Pokewalker};
return true;
}
/// <summary>
/// Returns false and no <see cref="PIDIV"/>.
/// </summary>
/// <param name="pidiv">Null</param>
/// <returns>False</returns>
[MethodImpl(MethodImplOptions.AggressiveInlining)]
private static bool GetNonMatch(out PIDIV pidiv)
{
pidiv = null;
return false;
}
private static PIDIV AnalyzeGB(PKM pk)
{
return null;
}
private static IEnumerable<uint> GetSeedsFromPID(RNG method, uint a, uint b)
{
Debug.Assert(a >> 16 == 0);
Debug.Assert(b >> 16 == 0);
uint second = a << 16;
uint first = b << 16;
return method.RecoverLower16Bits(first, second);
}
private static IEnumerable<uint> GetSeedsFromIVs(RNG method, uint a, uint b)
{
Debug.Assert(a >> 15 == 0);
Debug.Assert(b >> 15 == 0);
uint second = a << 16;
uint first = b << 16;
var pairs = method.RecoverLower16Bits(first, second)
.Concat(method.RecoverLower16Bits(first, second ^ 0x80000000));
foreach (var z in pairs)
{
yield return z;
yield return z ^ 0x80000000; // sister bitflip
}
}
public static IEnumerable<uint> GetSeedsFromIVsSkip(RNG method, uint rand1, uint rand3)
{
Debug.Assert(rand1 >> 15 == 0);
Debug.Assert(rand3 >> 15 == 0);
rand1 <<= 16;
rand3 <<= 16;
var seeds = method.RecoverLower16BitsGap(rand1, rand3)
.Concat(method.RecoverLower16BitsGap(rand1, rand3 ^ 0x80000000));
foreach (var z in seeds)
{
yield return z;
yield return z ^ 0x80000000; // sister bitflip
}
}
public static IEnumerable<uint> GetSeedsFromPIDEuclid(RNG method, uint rand1, uint rand2)
{
return method.RecoverLower16BitsEuclid16(rand1 << 16, rand2 << 16);
}
public static IEnumerable<uint> GetSeedsFromIVsEuclid(RNG method, uint rand1, uint rand2)
{
return method.RecoverLower16BitsEuclid15(rand1 << 16, rand2 << 16);
}
/// <summary>
/// Generates IVs from 2 RNG calls using 15 bits of each to generate 6 IVs (5bits each).
/// </summary>
/// <param name="r1">First rand frame</param>
/// <param name="r2">Second rand frame</param>
/// <returns>Array of 6 IVs</returns>
private static uint[] GetIVs(uint r1, uint r2)
{
return new[]
{
r1 & 31,
r1 >> 5 & 31,
r1 >> 10 & 31,
r2 & 31,
r2 >> 5 & 31,
r2 >> 10 & 31,
};
}
internal static int[] GetIVsInt32(uint r1, uint r2)
{
return new[]
{
(int)r1 & 31,
(int)r1 >> 5 & 31,
(int)r1 >> 10 & 31,
(int)r2 & 31,
(int)r2 >> 5 & 31,
(int)r2 >> 10 & 31,
};
}
private static uint GetIVChunk(uint[] IVs, int start)
{
uint val = 0;
for (int i = 0; i < 3; i++)
val |= IVs[i+start] << (5*i);
return val;
}
public static IEnumerable<PIDIV> GetPokeSpotSeeds(PKM pkm, int slot)
{
// Activate (rand % 3)
// Munchlax / Bonsly (10%/30%)
// Encounter Slot Value (ESV) = 50%/35%/15% rarity (0-49, 50-84, 85-99)
var pid = pkm.PID;
var top = pid >> 16;
var bot = pid & 0xFFFF;
var seeds = GetSeedsFromPIDEuclid(RNG.XDRNG, top, bot);
foreach (var seed in seeds)
{
// check for valid encounter slot info
var esv = (seed>>16)%100;
switch (slot)
{
case 0:
if (esv < 50) break; // valid
continue;
case 1:
if (esv >= 50 && esv < 85) break; // valid
continue;
case 2:
if (esv >= 85) break;
continue;
default:
continue;
}
// check for valid activation
var s = RNG.XDRNG.Prev(seed);
if ((s>>16)%3 != 0)
{
if ((s>>16)%100 < 10) // can't fail a munchlax/bonsly encounter check
continue;
s = RNG.XDRNG.Prev(s);
if ((s>>16)%3 != 0) // can't activate even if generous
continue;
}
yield return new PIDIV {OriginSeed = s, RNG = RNG.XDRNG, Type = PIDType.PokeSpot};
}
}
public static bool IsCompatible3(this PIDType val, IEncounterable encounter, PKM pkm)
{
switch (encounter)
{
case WC3 g:
return val == g.Method;
case EncounterStaticShadow d when d.EReader:
return val == PIDType.None; // All IVs are 0
case EncounterStatic s:
switch (pkm.Version)
{
case (int)GameVersion.CXD: return val == PIDType.CXD;
case (int)GameVersion.E: return val == PIDType.Method_1; // no roamer glitch
case (int)GameVersion.FR:
case (int)GameVersion.LG:
return s.Roaming ? val == PIDType.Method_1_Roamer : val == PIDType.Method_1; // roamer glitch
default: // RS, roamer glitch && RSBox s/w emulation => method 4 available
return s.Roaming ? val == PIDType.Method_1_Roamer : MethodH14.Any(z => z == val);
}
case EncounterSlot w:
if (pkm.Version == 15)
return val == PIDType.PokeSpot;
return (w.Species == 201 ? MethodH_Unown : MethodH).Any(z => z == val);
default:
return val == PIDType.None;
}
}
public static bool IsCompatible4(this PIDType val, IEncounterable encounter, PKM pkm)
{
switch (encounter)
{
case EncounterStatic s:
if (s == Encounters4.SpikyEaredPichu // nonshiny forced nature
|| s.Location == 233 && s.Gift) // Pokewalker
return val == PIDType.Pokewalker;
return s.Shiny == true ? val == PIDType.ChainShiny : val == PIDType.Method_1;
case EncounterSlot sl:
if (val == PIDType.Method_1)
return true;
if (val == PIDType.CuteCharm)
// Cute charm does not work with swarms pokemon
return sl.Type != SlotType.Swarm;
if (val != PIDType.ChainShiny)
return false;
// Chain shiny with poke radar is only possible in DPPt in tall grass, safari zone do not allow pokeradar
// TypeEncounter TallGrass discard any cave or city
var IsDPPt = GameVersion.DP.Contains((GameVersion)pkm.Version) || (GameVersion)pkm.Version == GameVersion.Pt;
return pkm.IsShiny && IsDPPt && sl.TypeEncounter == EncounterType.TallGrass && !Encounters4.SafariZoneLocation_4.Contains(sl.Location);
case PGT _: // manaphy
return IsG4ManaphyPIDValid(val, pkm);
default:
return val == PIDType.None;
}
}
private static bool IsG4ManaphyPIDValid(PIDType val, PKM pkm)
{
if (pkm.IsEgg)
{
if (pkm.IsShiny)
return false;
if (val == PIDType.Method_1)
return true;
return val == PIDType.G4MGAntiShiny && IsAntiShinyARNG();
}
if (val == PIDType.Method_1)
return pkm.WasTradedEgg || !pkm.IsShiny; // can't be shiny on received game
return val == PIDType.G4MGAntiShiny && (pkm.WasTradedEgg || IsAntiShinyARNG());
bool IsAntiShinyARNG()
{
var shinyPID = RNG.ARNG.Prev(pkm.PID);
return (pkm.TID ^ pkm.SID ^ (shinyPID & 0xFFFF) ^ (shinyPID >> 16)) < 8; // shiny proc
}
}
private static readonly PIDType[] MethodH = { PIDType.Method_1, PIDType.Method_2, PIDType.Method_4 };
private static readonly PIDType[] MethodH14 = { PIDType.Method_1, PIDType.Method_4 };
private static readonly PIDType[] MethodH_Unown = { PIDType.Method_1_Unown, PIDType.Method_2_Unown, PIDType.Method_4_Unown };
}
}