refactoring

src/main/kotlin/eventDemo/app/GameState.kt

@@ -0,0 +1,145 @@
+package eventDemo.app
+
+import eventDemo.app.entity.Card
+import eventDemo.app.entity.Deck
+import eventDemo.app.entity.Player
+import kotlinx.serialization.Serializable
+
+@Serializable
+data class GameState(
+    val gameId: GameId,
+    val players: Set<Player> = emptySet(),
+    val lastPlayer: Player? = null,
+    val lastCard: LastCard? = null,
+    val lastColor: Card.Color? = null,
+    val direction: Direction = Direction.CLOCKWISE,
+    val readyPlayers: List<Player> = emptyList(),
+    val deck: Deck = Deck(players.toList()),
+    val isStarted: Boolean = false,
+) {
+    @Serializable
+    data class LastCard(
+        val card: Card,
+        val player: Player,
+    )
+
+    enum class Direction {
+        CLOCKWISE,
+        COUNTER_CLOCKWISE,
+        ;
+
+        fun revert(): Direction =
+            if (this === CLOCKWISE) {
+                COUNTER_CLOCKWISE
+            } else {
+                CLOCKWISE
+            }
+    }
+
+    val isReady: Boolean get() {
+        return players.size == readyPlayers.size && players.all { readyPlayers.contains(it) }
+    }
+
+    fun canBePlayThisCard(
+        player: Player,
+        card: Card,
+    ): Boolean {
+        if (!isReady) return false
+        val cardOnGame = lastCard?.card ?: return false
+
+        return when (cardOnGame) {
+            is Card.NumericCard -> {
+                when (card) {
+                    is Card.AllColorCard -> true
+                    is Card.NumericCard -> card.number == cardOnGame.number || card.color == cardOnGame.color
+                    is Card.ColorCard -> card.color == cardOnGame.color
+                }
+            }
+
+            is Card.ReverseCard -> {
+                when (card) {
+                    is Card.ReverseCard -> true
+                    is Card.AllColorCard -> true
+                    is Card.ColorCard -> card.color == cardOnGame.color
+                }
+            }
+
+            is Card.PassCard -> {
+                if (player.cardOnBoardIsForYou) {
+                    false
+                } else {
+                    when (card) {
+                        is Card.AllColorCard -> true
+                        is Card.ColorCard -> card.color == cardOnGame.color
+                    }
+                }
+            }
+
+            is Card.ChangeColorCard -> {
+                when (card) {
+                    is Card.AllColorCard -> true
+                    is Card.ColorCard -> card.color == lastColor
+                }
+            }
+
+            is Card.Plus2Card -> {
+                if (player.cardOnBoardIsForYou && card is Card.Plus2Card) {
+                    true
+                } else {
+                    when (card) {
+                        is Card.AllColorCard -> true
+                        is Card.Plus2Card -> true
+                        is Card.ColorCard -> card.color == cardOnGame.color
+                    }
+                }
+            }
+
+            is Card.Plus4Card -> {
+                if (player.cardOnBoardIsForYou && card is Card.Plus4Card) {
+                    true
+                } else {
+                    when (card) {
+                        is Card.AllColorCard -> true
+                        is Card.ColorCard -> card.color == lastColor
+                    }
+                }
+            }
+        }
+    }
+
+    private val lastPlayerIndex: Int? get() {
+        val i = players.indexOf(lastPlayer)
+        return if (i == -1) {
+            null
+        } else {
+            i
+        }
+    }
+
+    private val nextPlayerIndex: Int get() {
+        val y =
+            if (direction == Direction.CLOCKWISE) {
+                +1
+            } else {
+                -1
+            }
+
+        return ((lastPlayerIndex ?: 0) + y) % players.size
+    }
+
+    val nextPlayer: Player = players.elementAt(nextPlayerIndex)
+
+    private val Player.currentIndex: Int get() = players.indexOf(this)
+
+    private fun Player.playerDiffIndex(nextPlayer: Player): Int =
+        if (direction == Direction.CLOCKWISE) {
+            nextPlayer.currentIndex + this.currentIndex
+        } else {
+            nextPlayer.currentIndex - this.currentIndex
+        }.let { it % players.size }
+
+    val Player.cardOnBoardIsForYou: Boolean get() {
+        if (lastCard == null) error("No card")
+        return this.playerDiffIndex(lastCard.player) == 1
+    }
+}