/// <summary>
/// Checks if <see cref="Yakus"/> and <see cref="YakusCombinations"/> have to be cancelled because of the temporary furiten rule.
/// </summary>
/// <param name="currentRound">The current round</param>
/// <param name="playerIndex">The player index of the hand.</param>
/// <returns><c>True</c> if temporary furiten; <c>False</c> otherwise.</returns>
internal bool CancelYakusIfTemporaryFuriten(RoundPivot currentRound, int playerIndex)
{
if (currentRound == null)
{
return(false);
}
int i = 0;
while (currentRound.PlayerIndexHistory.Count < i &&
currentRound.PlayerIndexHistory.ElementAt(i) == playerIndex.RelativePlayerIndex(-(i + 1)) &&
playerIndex.RelativePlayerIndex(-(i + 1)) != playerIndex)
{
// The tile discarded by the latest player is the tile we ron !
if (i > 0)
{
TilePivot lastFromDiscard = currentRound.GetDiscard(currentRound.PlayerIndexHistory.ElementAt(i)).LastOrDefault();
if (lastFromDiscard != null && IsCompleteFull(new List <TilePivot>(ConcealedTiles)
{
lastFromDiscard
}, DeclaredCombinations.ToList()))
{
Yakus = null;
YakusCombinations = null;
return(true);
}
}
i++;
}
return(false);
}
/// <summary>
/// Checks if the hand has finished on a closed wait.
/// </summary>
/// <returns><c>True</c> if contains a closed wait; <c>False</c> otherwise.</returns>
public bool HandWithClosedWait()
{
if (YakusCombinations == null)
{
return(false);
}
// The combination with the last pick.
TileComboPivot combo = YakusCombinations.FirstOrDefault(c => c.Tiles.Any(t => ReferenceEquals(t, LatestPick)));
if (combo == null || combo.IsBrelanOrSquare)
{
return(false);
}
// Other concealed (and not declared) combinations with the same tile.
List <TileComboPivot> otherCombos =
YakusCombinations
.Where(c => c != combo && !DeclaredCombinations.Contains(c) && c.Tiles.Contains(LatestPick))
.ToList();
// The real "LatestPick" is closed...
bool isClosed = combo.IsPair || LatestPick.TileIsMiddleWait(combo) || LatestPick.TileIsEdgeWait(combo);
// .. but there might be not-closed alternatives with the same tile as "LatestPick" in other combination.
bool alternative1 = otherCombos.Any(c => c.IsBrelanOrSquare);
bool alternative2 = otherCombos.Any(c => c.IsSequence && !LatestPick.TileIsMiddleWait(c) && !LatestPick.TileIsEdgeWait(c));
return(isClosed && !(alternative1 || alternative2));
}
/// <summary>
/// Checks if <see cref="Yakus"/> and <see cref="YakusCombinations"/> have to be cancelled because of the furiten rule.
/// </summary>
/// <param name="discard">The discard of the current player.</param>
/// <param name="opponentDiscards">
/// Aggregation of discards from opponents since the riichi call; includes tiles stolen by another opponent and tiles used to call opened kan.
/// </param>
/// <returns><c>True</c> if furiten; <c>False</c> otherwise.</returns>
internal bool CancelYakusIfFuriten(IEnumerable <TilePivot> discard, IEnumerable <TilePivot> opponentDiscards)
{
if (discard?.Any(t => IsCompleteFull(new List <TilePivot>(ConcealedTiles)
{
t
}, DeclaredCombinations.ToList())) == true)
{
Yakus = null;
YakusCombinations = null;
return(true);
}
if (opponentDiscards?.Any(t => IsCompleteFull(new List <TilePivot>(ConcealedTiles)
{
t
}, DeclaredCombinations.ToList())) == true)
{
Yakus = null;
YakusCombinations = null;
return(true);
}
return(false);
}
