lucas/Shogi
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

checkmate complete

Browse Source
This commit is contained in:
Lucas Morgan
2022-06-10 21:53:05 -05:00
parent dabdb6c6b0
commit 2dcc6ca417
7 changed files with 53 additions and 66 deletions
Download Patch File Download Diff File Expand all files Collapse all files

9
Shogi.Domain/DomainExtensions.cs
View File

@@ -6,5 +6,14 @@ namespace Shogi.Domain
{
public static bool IsKing(this Piece self) => self.WhichPiece == WhichPiece.King;
public static bool IsBetween(this float self, float min, float max)
{
return self >= min && self <= max;
}
public static bool IsInsideBoardBoundary(this Vector2 self)
{
return self.X.IsBetween(0, 8) && self.Y.IsBetween(0, 8);
}
}
}

1
Shogi.Domain/Pathing/Path.cs
View File

@@ -29,6 +29,7 @@ namespace Shogi.Domain.Pathing
{
throw new ArgumentException("No paths to get nearest path from.");
}
var shortestPath = paths.First();
foreach (var path in paths.Skip(1))
{

2
Shogi.Domain/Pieces/GoldGeneral.cs
View File

@@ -26,6 +26,6 @@ namespace Shogi.Domain.Pieces
{
}
public override IEnumerable<Path> MoveSet => Player1Paths;
public override IEnumerable<Path> MoveSet => Owner == WhichPlayer.Player1 ? Player1Paths : Player2Paths;
}
}

2
Shogi.Domain/Pieces/Piece.cs
View File

@@ -72,6 +72,8 @@ namespace Shogi.Domain.Pieces
{
position += path.Direction;
steps.Add(position);
if (path.Distance == Distance.OneStep) break;
}
if (position == end)

9
Shogi.Domain/Shogi.cs
View File

@@ -58,11 +58,10 @@ namespace Shogi.Domain
if (rules.IsOpponentInCheckAfterMove())
{
boardState.InCheck = otherPlayer;
// TODO: evaluate checkmate.
//if (rules.IsOpponentInCheckMate())
//{
// boardState.IsCheckmate = true;
//}
if (rules.IsOpponentInCheckMate())
{
boardState.IsCheckmate = true;
}
}
else
{

89
Shogi.Domain/StandardRules.cs
View File

@@ -1,4 +1,5 @@
using Shogi.Domain.Pathing;
using Shogi.Domain.Pieces;
using BoardTile = System.Collections.Generic.KeyValuePair<System.Numerics.Vector2, Shogi.Domain.Pieces.Piece>;
namespace Shogi.Domain
@@ -9,7 +10,7 @@ namespace Shogi.Domain
internal StandardRules(ShogiBoardState board)
{
this.boardState = board;
boardState = board;
}
/// <summary>
@@ -179,19 +180,17 @@ namespace Shogi.Domain
return threatenedPiece.WhichPiece == WhichPiece.King;
}
internal bool IsPlayerInCheckMate(WhichPlayer whichPlayer)
internal bool IsOpponentInCheckMate()
{
// Assume checkmate, then try to disprove.
if (!boardState.InCheck.HasValue) return false;
// Get all pieces from "other player" who threaten the king in question.
var otherPlayer = whichPlayer == WhichPlayer.Player1 ? WhichPlayer.Player2 : WhichPlayer.Player1;
var tilesOccupiedByOtherPlayer = boardState.GetTilesOccupiedBy(otherPlayer);
var kingPosition = whichPlayer == WhichPlayer.Player1
// Get all pieces from opponent who threaten the king in question.
var opponent = boardState.WhoseTurn == WhichPlayer.Player1 ? WhichPlayer.Player2 : WhichPlayer.Player1;
var tilesOccupiedByOpponent = boardState.GetTilesOccupiedBy(opponent);
var kingPosition = boardState.WhoseTurn == WhichPlayer.Player1
? boardState.Player1KingPosition
: boardState.Player2KingPosition;
var threats = tilesOccupiedByOtherPlayer.Where(tile => PieceHasLineOfSight(tile, kingPosition)).ToList();
var threats = tilesOccupiedByOpponent.Where(tile => PieceHasLineOfSight(tile, kingPosition)).ToList();
if (threats.Count == 1)
{
/* If there is exactly one threat it is possible to block the check.
@@ -200,7 +199,7 @@ namespace Shogi.Domain
*/
var threat = threats.Single();
var pathFromThreatToKing = threat.Value.GetPathFromStartToEnd(threat.Key, kingPosition);
var tilesThatCouldBlockTheThreat = boardState.GetTilesOccupiedBy(whichPlayer);
var tilesThatCouldBlockTheThreat = boardState.GetTilesOccupiedBy(boardState.WhoseTurn);
foreach (var threatBlockingPosition in pathFromThreatToKing)
{
var tilesThatDoBlockThreat = tilesThatCouldBlockTheThreat
@@ -218,25 +217,35 @@ namespace Shogi.Domain
/*
* If no ability to block the check, maybe the king can evade check by moving.
*/
// TODO: Implement this in the Piece class instead.
var possibleSafePositions = new[]
foreach (var maybeSafePosition in GetPossiblePositionsForKing(this.boardState.WhoseTurn))
{
Direction.Up, Direction.Down, Direction.Left, Direction.Right, Direction.UpLeft, Direction.UpRight, Direction.DownLeft, Direction.DownRight
}
.Select(direction => kingPosition + direction);
foreach (var maybeSafePosition in possibleSafePositions)
{
threats = tilesOccupiedByOpponent
.Where(tile => PieceHasLineOfSight(tile, maybeSafePosition))
.ToList();
if (!threats.Any())
{
return false;
}
}
}
return true;
}
private IList<Vector2> GetPossiblePositionsForKing(WhichPlayer whichPlayer)
{
var kingPosition = whichPlayer == WhichPlayer.Player1
? boardState.Player1KingPosition
: boardState.Player2KingPosition;
return false;
return King.KingPaths
.Select(path => path.Direction + kingPosition)
.Where(newPosition => newPosition.IsInsideBoardBoundary())
// Where tile at position is empty, meaning the king could move there.
.Where(newPosition => boardState[newPosition] == null)
.ToList();
}
private bool PieceHasLineOfSight(BoardTile tile, Vector2 lineOfSightTarget)
@@ -244,41 +253,7 @@ namespace Shogi.Domain
var path = tile.Value.GetPathFromStartToEnd(tile.Key, lineOfSightTarget);
return path
.SkipLast(1)
.All(position => this.boardState[ShogiBoardState.ToBoardNotation(position)] == null);
}
public bool EvaluateCheckmate_Old()
{
if (!boardState.InCheck.HasValue) return false;
// Assume true and try to disprove.
var isCheckmate = true;
//boardState.ForEachNotNull((piece, from) => // For each piece...
//{
// Short circuit
//if (!isCheckmate) return;
//if (piece.Owner == boardState.InCheck) // ...owned by the player in check...
//{
// ...evaluate if any move gets the player out of check.
//PathEvery(from, (other, position) =>
//{
// var simulationBoard = new StandardRules(new ShogiBoardState(board));
// var fromNotation = ShogiBoardState.ToBoardNotation(from);
// var toNotation = ShogiBoardState.ToBoardNotation(position);
// var simulationResult = simulationBoard.Move(fromNotation, toNotation, false);
// if (simulationResult.Success)
// {
// //if (!IsPlayerInCheckAfterMove(from, position, board.InCheck.Value))
// //{
// // isCheckmate = false;
// //}
// }
//});
//}
// TODO: Assert that a player could not place a piece from their hand to avoid check.
//});
return isCheckmate;
.All(position => boardState[ShogiBoardState.ToBoardNotation(position)] == null);
}
}
}