Remove Tetris references and rename to generic game pieces

app/src/main/java/com/pixelmintdrop/model/GameBoard.kt

@@ -17,18 +17,18 @@ class GameBoard(
     // True = occupied, False = empty
     private val grid = Array(height) { BooleanArray(width) { false } }
     
-    // Current active tetromino
-    private var currentPiece: Tetromino? = null
+    // Current active piece
+    private var currentPiece: GamePiece? = null
     
-    // Next tetromino to be played
-    private var nextPiece: Tetromino? = null
+    // Next piece to be played
+    private var nextPiece: GamePiece? = null
     
     // Hold piece
-    private var holdPiece: Tetromino? = null
+    private var holdPiece: GamePiece? = null
     private var canHold = true
     
     // 7-bag randomizer
-    private val bag = mutableListOf<TetrominoType>()
+    private val bag = mutableListOf<GamePieceType>()
     
     // Game state
     var score = 0
@@ -43,7 +43,7 @@ class GameBoard(
     
     // Scoring state
     private var combo = 0
-    private var lastClearWasTetris = false
+    private var lastClearWasQuad = false
     private var lastClearWasPerfect = false
     private var lastClearWasAllClear = false
     private var lastPieceClearedLines = false  // Track if the last piece placed cleared lines
@@ -80,12 +80,12 @@ class GameBoard(
     private fun spawnNextPiece() {
         // If bag is empty, refill it with all piece types
         if (bag.isEmpty()) {
-            bag.addAll(TetrominoType.entries.toTypedArray())
+            bag.addAll(GamePieceType.entries.toTypedArray())
             bag.shuffle()
         }
         
         // Take the next piece from the bag
-        nextPiece = Tetromino(bag.removeAt(0))
+        nextPiece = GamePiece(bag.removeAt(0))
         onNextPieceChanged?.invoke()
     }
     
@@ -122,12 +122,12 @@ class GameBoard(
     /**
      * Get the currently held piece
      */
-    fun getHoldPiece(): Tetromino? = holdPiece
+    fun getHoldPiece(): GamePiece? = holdPiece
     
     /**
      * Get the next piece that will be spawned
      */
-    fun getNextPiece(): Tetromino? = nextPiece
+    fun getNextPiece(): GamePiece? = nextPiece
     
     /**
      * Spawns the current tetromino at the top of the board
@@ -541,8 +541,8 @@ class GameBoard(
             }
         } else 1.0
         
-        // Calculate back-to-back Tetris bonus
-        val backToBackMultiplier = if (clearedLines == 4 && lastClearWasTetris) 1.5 else 1.0
+        // Calculate back-to-back quad bonus
+        val backToBackMultiplier = if (clearedLines == 4 && lastClearWasQuad) 1.5 else 1.0
         
         // Calculate perfect clear bonus
         val perfectClearMultiplier = if (isPerfectClear) {
@@ -579,7 +579,7 @@ class GameBoard(
         }.start()
         
         // Update line clear state
-        lastClearWasTetris = clearedLines == 4
+        lastClearWasQuad = clearedLines == 4
         lastClearWasPerfect = isPerfectClear
         lastClearWasAllClear = isAllClear
         
@@ -597,7 +597,7 @@ class GameBoard(
      */
     private fun isTSpin(): Boolean {
         val piece = currentPiece ?: return false
-        if (piece.type != TetrominoType.T) return false
+        if (piece.type != GamePieceType.T) return false
         
         // Count occupied corners around the T piece
         var occupiedCorners = 0
@@ -637,7 +637,7 @@ class GameBoard(
     /**
      * Get the current tetromino
      */
-    fun getCurrentPiece(): Tetromino? = currentPiece
+    fun getCurrentPiece(): GamePiece? = currentPiece
     
     /**
      * Check if a cell in the grid is occupied
@@ -702,7 +702,7 @@ class GameBoard(
         
         // Reset scoring state
         combo = 0
-        lastClearWasTetris = false
+        lastClearWasQuad = false
         lastClearWasPerfect = false
         lastClearWasAllClear = false
         lastPieceClearedLines = false