Many many changes

api/move.go

@@ -2,7 +2,7 @@ package api
 
 import (
 	"encoding/json"
-	"local/m/mchess_server/types"
+	"mchess_server/types"
 )
 
 type WebsocketMessage struct {

chess/bishop.go

@@ -1,18 +1,15 @@
 package chess
 
-import "local/m/mchess_server/types"
+import "mchess_server/types"
 
 type Bishop struct {
 	Color types.ChessColor
 }
 
-func (Bishop) AfterMoveAction() {
-}
-
 func (b Bishop) GetColor() types.ChessColor {
 	return b.Color
 }
 
-func (b Bishop) GetAllLegalAndIllegalMoves(board Board, fromSquare types.Coordinate) []types.Coordinate {
+func (b Bishop) GetAllMovesButBlocked(board Board, fromSquare types.Coordinate) []types.Coordinate {
 	return []types.Coordinate{}
 }

chess/board.go

@@ -1,7 +1,7 @@
 package chess
 
 import (
-	"local/m/mchess_server/types"
+	"mchess_server/types"
 
 	"github.com/samber/lo"
 )
@@ -14,11 +14,11 @@ func (b Board) Init() {
 	for i := 1; i <= 8; i++ {
 		coord.Row = 2
 		coord.Col = i
-		b[coord] = Pawn{Color: types.White, HasMoved: false}
+		b[coord] = Pawn{Color: types.White}
 
 		coord.Row = 7
 		coord.Col = i
-		b[coord] = Pawn{Color: types.Black, HasMoved: false}
+		b[coord] = Pawn{Color: types.Black}
 	}
 
 	b[types.Coordinate{Row: 1, Col: 1}] = Rook{Color: types.White}
@@ -41,39 +41,58 @@ func (b Board) Init() {
 }
 
 func (b Board) CheckMove(move types.Move) (bool, string) {
+	// We make a copy of the original board to play moves on it,
+	// We can play the move on it and then check if it is invalid
+	tempBoard := b.getCopyOfBoard()
+
+	//Check start square of move
 	pieceAtStartSquare := b.getPieceAt(move.StartSquare)
 	if pieceAtStartSquare == nil {
 		return false, "no piece at start square"
 	}
 	movingColor := pieceAtStartSquare.GetColor()
 
+	//Check end square of move
 	pieceAtEndSquare := b.getPieceAt(move.EndSquare)
 	if pieceAtEndSquare != nil {
 		if pieceAtEndSquare.GetColor() == pieceAtStartSquare.GetColor() {
 			return false, "same-coloured piece at end square"
 		}
 	}
-	// At the moment, we do not need to check if the correct color is moving,
-	//since we are only reading moves from the player whose turn it is.
+	var wasPromotionMove bool
+	// var piece types.PieceShortName
+	switch pieceAtStartSquare.(type) {
+	case Pawn:
+		wasPromotionMove, _ = tempBoard.handlePossiblePromotion(move, movingColor)
+	}
 
-	legal := lo.Contains(pieceAtStartSquare.GetAllLegalAndIllegalMoves(b, move.StartSquare), move.EndSquare)
-	if !legal {
-		return false, "not a legal square"
+	if !wasPromotionMove {
+		// At the moment, we do not need to check if the correct color is moving,
+		//since we are only reading moves from the player whose turn it is.
+		allMovesExceptBlocked := pieceAtStartSquare.GetAllMovesButBlocked(tempBoard, move.StartSquare)
+		legal := lo.Contains(allMovesExceptBlocked, move.EndSquare)
+		if !legal {
+			return false, "not a legal square"
+		}
+
+		//We play the move on the temporary board
+		delete(tempBoard, move.StartSquare)
+		tempBoard[move.EndSquare] = pieceAtStartSquare
 	}
 
 	//Check if king of moving color is in check -> move not allowed
 	//Do that by checking if the king is in a square attacked by the other color.
-	ownKingCoordinate := b.getSquareOfPiece(King{Color: movingColor})
+	ownKingCoordinate := tempBoard.getSquareOfPiece(King{Color: movingColor})
 	if ownKingCoordinate == nil {
 		return false, string(movingColor) + " king not found"
 	}
 
-	kingIsAttacked := b.isSquareAttacked(*ownKingCoordinate, movingColor.Opposite())
+	kingIsAttacked := tempBoard.isSquareAttacked(*ownKingCoordinate, movingColor.Opposite())
 	if kingIsAttacked {
 		return false, "king is attacked after move"
 	}
 
-	//Check for checkmate
+	//Check for checkmat&e
 	//Is every square that the king can move to attacked? And can no other
 	//piece block? -> checkmate
 
@@ -86,11 +105,9 @@ func (b Board) CheckMove(move types.Move) (bool, string) {
 	// in this scenaria the path are all the squares between queen and king.
 	// If a piece can be moved into the path, it is no checkmate
 
-    //We play the move
-    delete(b, move.StartSquare)
-    b[move.EndSquare] = pieceAtStartSquare
+	//We play the move on the real board
+	b = tempBoard
 
-    pieceAtStartSquare.AfterMoveAction()
 	return true, ""
 }
 
@@ -107,7 +124,7 @@ func (b Board) isSquareAttacked(square types.Coordinate, byColor types.ChessColo
 	var attackedSquares []types.Coordinate
 
 	for square, piece := range b {
-		attackedSquares = append(attackedSquares, piece.GetAllLegalAndIllegalMoves(b, square)...)
+		attackedSquares = append(attackedSquares, piece.GetAllMovesButBlocked(b, square)...)
 	}
 
 	return lo.Contains(attackedSquares, square)
@@ -115,10 +132,51 @@ func (b Board) isSquareAttacked(square types.Coordinate, byColor types.ChessColo
 
 func (b Board) getPieceAt(coord types.Coordinate) Piece {
 	piece, found := b[coord]
-
 	if !found {
 		return nil
 	}
 
 	return piece
 }
+
+func (b Board) handlePossiblePromotion(move types.Move, color types.ChessColor) (bool, types.PieceShortName) {
+	var isPromotionMove bool
+	var promotionToPiece types.PieceShortName
+
+	messageContainsPromotion := move.IsPromotionMove()
+
+	if messageContainsPromotion {
+		promotionToPiece = *move.PromotionToPiece
+	}
+
+	switch color {
+	case types.White:
+		if move.StartSquare.Row == types.RangeLastValid-1 &&
+			move.EndSquare.Row == types.RangeLastValid {
+			isPromotionMove = true
+		}
+
+	case types.Black:
+		if move.StartSquare.Row == types.RangeFirstValid+1 &&
+			move.EndSquare.Row == types.RangeFirstValid {
+			isPromotionMove = true
+		}
+	}
+
+	if isPromotionMove {
+		delete(b, move.StartSquare)
+		b[move.EndSquare] = GetPieceForShortName(promotionToPiece)
+	}
+
+	return isPromotionMove, promotionToPiece
+}
+
+func (b Board) getCopyOfBoard() Board {
+	board := make(map[types.Coordinate]Piece)
+
+	for coord, piece := range b {
+		board[coord] = piece
+	}
+
+	return board
+}

chess/board_test.go

@@ -0,0 +1,71 @@
+package chess
+
+import (
+	"mchess_server/types"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_CheckMove_validPawnMove(t *testing.T) {
+	var board = make(Board)
+
+	board[types.Coordinate{Col: 1, Row: 1}] = Pawn{Color: types.White}
+	board[types.Coordinate{Col: 1, Row: 5}] = King{Color: types.White}
+	board[types.Coordinate{Col: 8, Row: 5}] = King{Color: types.Black}
+
+	move := types.Move{
+		StartSquare: types.Coordinate{Col: 1, Row: 1},
+		EndSquare:   types.Coordinate{Col: 1, Row: 2},
+	}
+
+	good, _ := board.CheckMove(move)
+	assert.True(t, good)
+}
+
+func Test_CheckMove_invalidPawnMoves(t *testing.T) {
+	var board = make(Board)
+
+	board[types.Coordinate{Col: 2, Row: 5}] = Pawn{Color: types.White}
+	board[types.Coordinate{Col: 1, Row: 5}] = King{Color: types.White}
+	board[types.Coordinate{Col: 7, Row: 5}] = Queen{Color: types.Black}
+	board[types.Coordinate{Col: 8, Row: 5}] = King{Color: types.Black}
+
+	move := types.Move{
+		StartSquare: types.Coordinate{Col: 2, Row: 5},
+		EndSquare:   types.Coordinate{Col: 2, Row: 6},
+	}
+
+	t.Run("pawn is blocked", func(t *testing.T) {
+		testBoard := board.getCopyOfBoard()
+		testBoard[types.Coordinate{Col: 2, Row: 6}] = Pawn{Color: types.Black}
+		legalMove, _ := testBoard.CheckMove(move)
+		assert.False(t, legalMove)
+	})
+
+	t.Run("king of moving color is in check after move", func(t *testing.T) {
+		good, _ := board.CheckMove(move)
+		assert.False(t, good)
+	})
+}
+
+func Test_CheckMove_validPromotion(t *testing.T) {
+	var board Board = make(Board)
+
+	board[types.Coordinate{Col: 1, Row: 7}] = Pawn{Color: types.White}
+	board[types.Coordinate{Col: 1, Row: 1}] = King{Color: types.White}
+
+	board[types.Coordinate{Col: 8, Row: 7}] = King{Color: types.Black}
+
+	shortName := types.Queen
+	move := types.Move{
+		StartSquare:      types.Coordinate{Col: 1, Row: 7},
+		EndSquare:        types.Coordinate{Col: 1, Row: 8},
+		PromotionToPiece: &shortName,
+	}
+
+	good, reason := board.CheckMove(move)
+
+	assert.Empty(t, reason)
+	assert.True(t, good)
+}

chess/game.go

@@ -1,8 +1,8 @@
 package chess
 
 import (
-	"local/m/mchess_server/api"
-	"local/m/mchess_server/types"
+	"mchess_server/api"
+	"mchess_server/types"
 	"log"
 	"time"
 

chess/king.go

@@ -1,22 +1,15 @@
 package chess
 
-import "local/m/mchess_server/types"
+import "mchess_server/types"
 
 type King struct {
 	Color    types.ChessColor
-	HasMoved bool
 }
 
-// AfterMoveAction implements Piece.
-func (k King) AfterMoveAction() {
-    k.HasMoved = true
-}
-
-// GetColor implements Piece.
 func (k King) GetColor() types.ChessColor {
 	return k.Color
 }
 
-func (k King) GetAllLegalAndIllegalMoves(board Board, fromSquare types.Coordinate) []types.Coordinate {
+func (k King) GetAllMovesButBlocked(board Board, fromSquare types.Coordinate) []types.Coordinate {
 	return []types.Coordinate{}
 }

chess/knight.go

@@ -1,19 +1,19 @@
 package chess
 
-import "local/m/mchess_server/types"
+import "mchess_server/types"
 
 type Knight struct {
 	Color types.ChessColor
 }
 
 // AfterMoveAction implements Piece.
-func (Knight) AfterMoveAction() {
+func (k Knight) AfterMoveAction() {
 }
 
 func (k Knight) GetColor() types.ChessColor {
 	return k.Color
 }
 
-func (k Knight) GetAllLegalAndIllegalMoves(board Board, fromSquare types.Coordinate) []types.Coordinate {
+func (k Knight) GetAllMovesButBlocked(board Board, fromSquare types.Coordinate) []types.Coordinate {
 	return []types.Coordinate{}
 }

chess/pawn.go

@@ -1,21 +1,16 @@
 package chess
 
 import (
-	"local/m/mchess_server/types"
+	"mchess_server/types"
 
 	"github.com/samber/lo"
 )
 
 type Pawn struct {
-	Color    types.ChessColor
-	HasMoved bool
+	Color types.ChessColor
 }
 
-func (p Pawn) AfterMoveAction() {
-	p.HasMoved = true
-}
-
-func (p Pawn) GetAllLegalAndIllegalMoves(board Board, fromSquare types.Coordinate) []types.Coordinate {
+func (p Pawn) GetAllMovesButBlocked(board Board, fromSquare types.Coordinate) []types.Coordinate {
 	theoreticalSquares := p.getAllMoves(fromSquare)
 	legalSquares := p.filterBlockedSquares(board, fromSquare, theoreticalSquares)
 
@@ -31,34 +26,38 @@ func (p Pawn) getAllMoves(fromSquare types.Coordinate) []types.Coordinate {
 
 	switch p.Color {
 	case types.Black:
-		if fromSquare.Down(1) != nil {
+		firstMove := fromSquare.Row == types.RangeLastValid-1
+		
+        if fromSquare.Down(1) != nil {
 			theoreticalMoves = append(theoreticalMoves, *fromSquare.Down(1))
 		}
-		if !p.HasMoved && fromSquare.Down(2) != nil {
+		if firstMove && fromSquare.Down(2) != nil {
 			theoreticalMoves = append(theoreticalMoves, *fromSquare.Down(2))
 		}
 
-        if lowerRight := fromSquare.Down(1).Right(1); lowerRight != nil {
-            theoreticalMoves = append(theoreticalMoves, *lowerRight)
-        }
-        if lowerLeft := fromSquare.Down(1).Left(1); lowerLeft != nil {
-            theoreticalMoves = append(theoreticalMoves, *lowerLeft)
-        }
+		if lowerRight := fromSquare.Down(1).Right(1); lowerRight != nil {
+			theoreticalMoves = append(theoreticalMoves, *lowerRight)
+		}
+		if lowerLeft := fromSquare.Down(1).Left(1); lowerLeft != nil {
+			theoreticalMoves = append(theoreticalMoves, *lowerLeft)
+		}
 
 	case types.White:
+		firstMove := fromSquare.Row == types.RangeFirstValid+1
+
 		if fromSquare.Up(1) != nil {
 			theoreticalMoves = append(theoreticalMoves, *fromSquare.Up(1))
 		}
-		if !p.HasMoved && fromSquare.Up(2) != nil {
+		if firstMove && fromSquare.Up(2) != nil {
 			theoreticalMoves = append(theoreticalMoves, *fromSquare.Up(2))
 		}
 
-        if upperRight := fromSquare.Up(1).Right(1); upperRight != nil {
-            theoreticalMoves = append(theoreticalMoves, *upperRight)
-        }
-        if upperLeft := fromSquare.Up(1).Left(1); upperLeft != nil {
-            theoreticalMoves = append(theoreticalMoves, *upperLeft)
-        }
+		if upperRight := fromSquare.Up(1).Right(1); upperRight != nil {
+			theoreticalMoves = append(theoreticalMoves, *upperRight)
+		}
+		if upperLeft := fromSquare.Up(1).Left(1); upperLeft != nil {
+			theoreticalMoves = append(theoreticalMoves, *upperLeft)
+		}
 	}
 
 	return theoreticalMoves

chess/piece_interface.go

@@ -1,11 +1,30 @@
 package chess
 
 import (
-	"local/m/mchess_server/types"
+	"mchess_server/types"
 )
 
 type Piece interface {
-	GetAllLegalAndIllegalMoves(board Board, fromSquare types.Coordinate) []types.Coordinate
+	GetAllMovesButBlocked(board Board, fromSquare types.Coordinate) []types.Coordinate
 	GetColor() types.ChessColor
-    AfterMoveAction()
+}
+
+func GetPieceForShortName(name types.PieceShortName) Piece {
+	var piece Piece
+
+	switch name {
+	case 'p':
+		piece = Pawn{}
+	case 'q':
+		piece = Queen{}
+	case 'k':
+		piece = King{}
+	case 'b':
+		piece = Bishop{}
+	case 'r':
+		piece = Rook{}
+	case 'n':
+		piece = Knight{}
+	}
+	return piece
 }

chess/player.go

@@ -4,8 +4,8 @@ import (
 	"context"
 	"encoding/json"
 	"errors"
-	"local/m/mchess_server/api"
-	"local/m/mchess_server/types"
+	"mchess_server/api"
+	"mchess_server/types"
 	"log"
 	"time"
 

chess/queen.go

@@ -1,18 +1,15 @@
 package chess
 
-import "local/m/mchess_server/types"
+import "mchess_server/types"
 
 type Queen struct {
 	Color types.ChessColor
 }
 
-func (Queen) AfterMoveAction() {
-}
-
 func (q Queen) GetColor() types.ChessColor {
 	return q.Color
 }
 
-func (q Queen) GetAllLegalAndIllegalMoves(board Board, fromSquare types.Coordinate) []types.Coordinate {
+func (q Queen) GetAllMovesButBlocked(board Board, fromSquare types.Coordinate) []types.Coordinate {
 	return []types.Coordinate{}
 }

chess/rook.go

@@ -1,13 +1,12 @@
 package chess
 
-import "local/m/mchess_server/types"
+import "mchess_server/types"
 
 type Rook struct {
 	Color    types.ChessColor
-	HasMoved bool
 }
 
-func (Rook) AfterMoveAction() {
+func (r Rook) AfterMoveAction() {
 }
 
 // GetColor implements Piece.
@@ -15,6 +14,6 @@ func (r Rook) GetColor() types.ChessColor {
 	return r.Color
 }
 
-func (r Rook) GetAllLegalAndIllegalMoves(board Board, fromSquare types.Coordinate) []types.Coordinate {
+func (r Rook) GetAllMovesButBlocked(board Board, fromSquare types.Coordinate) []types.Coordinate {
 	return []types.Coordinate{}
 }

go.mod

@@ -1,4 +1,4 @@
-module local/m/mchess_server
+module mchess_server
 
 go 1.20
 
@@ -12,6 +12,7 @@ require (
 require (
 	github.com/bytedance/sonic v1.8.0 // indirect
 	github.com/chenzhuoyu/base64x v0.0.0-20221115062448-fe3a3abad311 // indirect
+	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/gin-contrib/sse v0.1.0 // indirect
 	github.com/go-playground/locales v0.14.1 // indirect
 	github.com/go-playground/universal-translator v0.18.1 // indirect
@@ -25,7 +26,10 @@ require (
 	github.com/modern-go/concurrent v0.0.0-20180228061459-e0a39a4cb421 // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect
 	github.com/pelletier/go-toml/v2 v2.0.6 // indirect
+	github.com/pmezard/go-difflib v1.0.0 // indirect
 	github.com/samber/lo v1.38.1 // indirect
+	github.com/stretchr/objx v0.5.0 // indirect
+	github.com/stretchr/testify v1.8.4 // indirect
 	github.com/twitchyliquid64/golang-asm v0.15.1 // indirect
 	github.com/ugorji/go/codec v1.2.9 // indirect
 	golang.org/x/arch v0.0.0-20210923205945-b76863e36670 // indirect

go.sum

@@ -74,6 +74,7 @@ github.com/samber/lo v1.38.1 h1:j2XEAqXKb09Am4ebOg31SpvzUTTs6EN3VfgeLUhPdXM=
 github.com/samber/lo v1.38.1/go.mod h1:+m/ZKRl6ClXCE2Lgf3MsQlWfh4bn1bz6CXEOxnEXnEA=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
+github.com/stretchr/objx v0.5.0 h1:1zr/of2m5FGMsad5YfcqgdqdWrIhu+EBEJRhR1U7z/c=
 github.com/stretchr/objx v0.5.0/go.mod h1:Yh+to48EsGEfYuaHDzXPcE3xhTkx73EhmCGUpEOglKo=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
@@ -83,6 +84,8 @@ github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/
 github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
 github.com/stretchr/testify v1.8.1 h1:w7B6lhMri9wdJUVmEZPGGhZzrYTPvgJArz7wNPgYKsk=
 github.com/stretchr/testify v1.8.1/go.mod h1:w2LPCIKwWwSfY2zedu0+kehJoqGctiVI29o6fzry7u4=
+github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
+github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
 github.com/twitchyliquid64/golang-asm v0.15.1 h1:SU5vSMR7hnwNxj24w34ZyCi/FmDZTkS4MhqMhdFk5YI=
 github.com/twitchyliquid64/golang-asm v0.15.1/go.mod h1:a1lVb/DtPvCB8fslRZhAngC2+aY1QWCk3Cedj/Gdt08=
 github.com/ugorji/go v1.1.7/go.mod h1:kZn38zHttfInRq0xu/PH0az30d+z6vm202qpg1oXVMw=

lobby_registry/lobby.go

@@ -1,7 +1,7 @@
 package lobby_registry
 
 import (
-	"local/m/mchess_server/chess"
+	"mchess_server/chess"
 
 	"github.com/google/uuid"
 )
@@ -22,10 +22,10 @@ func NewEmptyLobbyWithUUID(uuid uuid.UUID) *Lobby {
 	}
 }
 
-func (w *Lobby) AddPlayerAndStartGameIfFull(player *chess.Player) {
-	w.Game.AddPlayersToGame(player)
-	if w.IsFull() {
-		go w.Game.Handle()
+func (l *Lobby) AddPlayerAndStartGameIfFull(player *chess.Player) {
+	l.Game.AddPlayersToGame(player)
+	if l.IsFull() {
+		go l.Game.Handle()
 	}
 }
 

main.go

@@ -4,10 +4,10 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
-	"local/m/mchess_server/api"
-	"local/m/mchess_server/chess"
-	lobbies "local/m/mchess_server/lobby_registry"
-	"local/m/mchess_server/usher"
+	"mchess_server/api"
+	"mchess_server/chess"
+	lobbies "mchess_server/lobby_registry"
+	"mchess_server/usher"
 	"log"
 	"net/http"
 	"os"

types/common.go

@@ -45,22 +45,6 @@ func (c Coordinate) Left(number int) *Coordinate {
 	return nil
 }
 
-type Move struct {
-	StartSquare Coordinate `json:"startSquare"`
-	EndSquare   Coordinate `json:"endSquare"`
-}
-
-type PieceClass string
-
-const (
-	Pawn   PieceClass = "pawn"
-	Rook   PieceClass = "rook"
-	Knight PieceClass = "knight"
-	Bishop PieceClass = "bishop"
-	Queen  PieceClass = "queen"
-	King   PieceClass = "king"
-)
-
 type ChessColor string
 
 const (

types/move.go

@@ -0,0 +1,14 @@
+package types
+
+type Move struct {
+	StartSquare Coordinate `json:"startSquare"`
+	EndSquare   Coordinate `json:"endSquare"`
+    PromotionToPiece *PieceShortName `json:"promotionToPiece,omitempty"` 
+}
+
+func (m Move) IsPromotionMove() bool {
+    if m.PromotionToPiece != nil {
+        return true
+    }
+    return false
+}

types/shortname.go

@@ -0,0 +1,12 @@
+package types
+
+type PieceShortName rune
+
+const (
+	Pawn   PieceShortName = 'p'
+	Rook   PieceShortName = 'r'
+	Knight PieceShortName = 'n'
+	Bishop PieceShortName = 'b'
+	Queen  PieceShortName = 'q'
+	King   PieceShortName = 'k'
+)

usher/usher.go

@@ -1,8 +1,8 @@
 package usher
 
 import (
-	"local/m/mchess_server/chess"
-	lobbies "local/m/mchess_server/lobby_registry"
+	"mchess_server/chess"
+	lobbies "mchess_server/lobby_registry"
 )
 
 type Usher struct {