implement holding

src/game.rs

@@ -95,7 +95,6 @@ impl Game {
 
     fn spawn_tetromino(&mut self) {
         self.playfield.spawn_tetromino();
-        self.playfield.tick_gravity();
         self.update_gravity_tick();
     }
 
@@ -195,20 +194,9 @@ impl Controllable for Game {
     }
 
     fn hold(&mut self) {
-        if self.can_swap_hold {
+        match self.playfield.try_swap_hold() {
-            match self.hold_piece {
+            Ok(_) => {}
-                None => {
+            Err(_) => (),
-                    self.hold_piece = Some(self.active_piece);
-                    self.get_new_piece();
-                }
-                Some(piece) => {
-                    self.hold_piece = Some(self.active_piece);
-                    self.active_piece = piece;
-                    self.reset_position();
-                }
-            }
-
-            self.can_swap_hold = false;
         }
     }
 }

src/playfield.rs

@@ -134,6 +134,7 @@ impl PlayField {
         ));
         self.next_pieces.push_back(self.bag.get_tetromino());
         self.can_swap_hold = true;
+        self.tick_gravity();
     }
 
     pub fn tick_gravity(&mut self) {
@@ -196,6 +197,25 @@ impl PlayField {
                     && self.field[*y as usize][*x as usize].is_none()
             })
     }
+
+    pub fn try_swap_hold(&mut self) -> Result<(), ()> {
+        if self.can_swap_hold {
+            match self.active_piece {
+                Some(piece) => {
+                    match self.hold_piece {
+                        Some(hold) => self.next_pieces.push_front(hold),
+                        None => (),
+                    }
+                    self.hold_piece = Some(piece.piece_type);
+                    self.spawn_tetromino();
+                    self.can_swap_hold = false;
+                }
+                None => return Err(()),
+            }
+        }
+
+        Err(())
+    }
 }
 
 impl Renderable for PlayField {

src/srs.rs

@@ -45,7 +45,6 @@ impl SRS {
         }
 
         let cur_offsets = offset_data.get(&test_tetromino.rotation_state).unwrap();
-
         let mut offsets = Vec::with_capacity(cur_offsets.len());
 
         for i in 0..cur_offsets.len() {