Simplify state machine.

server/game.go

@@ -12,9 +12,8 @@ type chessGame struct {
 }
 
 const (
-	WhiteToMove       = 0
-	BlackToMove       = 1
-	CheckPlayerChange = 2
+	PlayerToMove      = 0
+	CheckPlayerChange = 1
 )
 
 func NewChessGame(gameId int, players [2]Player) *chessGame {
@@ -28,7 +27,9 @@ func NewChessGame(gameId int, players [2]Player) *chessGame {
 
 func (game *chessGame) handle() {
 
-	gameState := WhiteToMove
+	defer log.Println("Game ", game.id, ": handle() ended")
+
+	gameState := PlayerToMove
 	game.currentTurnPlayer = game.players[0]
 	var move *chessMove
 	var messageType int
@@ -43,72 +44,56 @@ func (game *chessGame) handle() {
 	for {
 
 		switch gameState {
-		case WhiteToMove:
+		case PlayerToMove:
 			var err error
-			messageType, receivedMessage, err = ReadMessageFromPlayer(&game.players[0])
+			messageType, receivedMessage, err = ReadMessageFromPlayer(&game.currentTurnPlayer)
 			if err != nil {
-				log.Println("Error during message reading:", err)
+				log.Println("Error while reading message:", err)
+				// At the moment, we return when there is an error while reading a message.
+				// This means, the game just ends uncontrolled
 				return
 			}
 			move, err = parseMove(string(receivedMessage))
-			log.Println("Player 0 moved: ", move)
+			log.Println("Player ", game.currentTurnPlayer, " moved: ", move)
 
 			if err != nil {
 				log.Println("Game: ", game.id, err)
-				return
+				continue
 			}
 			gameState = CheckPlayerChange
 
-		case BlackToMove:
-			var err error
-			messageType, receivedMessage, err = ReadMessageFromPlayer(&game.players[1])
-			if err != nil {
-				log.Println("Error during message reading:", err)
-				return
-			}
-			move, err = parseMove(string(receivedMessage))
-
-			if err != nil {
-				log.Println("Game: ", game.id, err)
-				return
-			}
-			log.Println("Player 1 moved: ", move)
-
-			gameState = CheckPlayerChange
-
 		case CheckPlayerChange:
 
 			if move.realMove {
 				if game.currentTurnPlayer.id == game.players[0].id {
 					game.currentTurnPlayer = game.players[1]
-					gameState = BlackToMove
 				} else {
 					game.currentTurnPlayer = game.players[0]
-					gameState = WhiteToMove
 				}
 
 				err := WriteMessageToPlayer(&game.players[0], receivedMessage, messageType)
 				if err != nil {
 					log.Println("Error during message writing:", err)
-					break
+					continue
 				}
 				err = WriteMessageToPlayer(&game.players[1], receivedMessage, messageType)
 				if err != nil {
 					log.Println("Error during message writing:", err)
-					break
+					continue
 				}
+				gameState = PlayerToMove
 			} else {
-				if game.currentTurnPlayer.id == game.players[0].id {
-					gameState = WhiteToMove
-				} else {
-					gameState = BlackToMove
-				}
+				// Nothing to do if move was not real
 			}
 
 		}
 
 		log.Println("GameState = ", gameState)
+		if gameState == PlayerToMove {
+			log.Println("with player ", game.currentTurnPlayer, " to move")
+		}
 	}
+
 }
 
 func addPlayersToGame(players [2]Player) {