Started retro tetris game

Started developing a retro version of Tetris, following
the planning on the board of the classroom
(see planning.jpg).

Moved cursor work into cursor.

block.py

@@ -0,0 +1,10 @@
+class Block:
+    """A Block represents a single square on the Tetris board. 
+    Blocks are part of a Piece while they are 'alive'.
+    """
+    character = "X"
+    color = "blue"
+    alive = True
+
+    def __init__(self, position):
+        self.position = position

game.py

@@ -0,0 +1,7 @@
+from retro.game import Game
+from manager import Manager
+
+agents = [Manager()]
+state = {'level': 1}
+game = Game(agents, state, board_size=(20, 20), debug=True)
+game.play()

manager.py

@@ -0,0 +1,24 @@
+from piece import Piece, PIECE_DEFINITIONS
+from random import choice
+from retro.errors import AgentNotFoundByName
+
+class Manager:
+    """The Manager takes care of stuff that isn't anyone else's responsibility:
+    - Create a Piece whenever none exists.
+    - Clear full rows of Blocks (and move other Blocks down).
+    - End the game when the Blocks pile up all the way.
+    """
+    display = False
+
+    def play_turn(self, game):
+        try:
+            game.get_agent_by_name("piece")
+        except AgentNotFoundByName:
+            self.create_piece(game)
+
+    def create_piece(self, game):
+        width, height = game.board_size
+        piece = Piece((width//2, 2), game, choice(PIECE_DEFINITIONS))
+        game.add_agent(piece)
+
+

piece.py

@@ -0,0 +1,100 @@
+from block import Block
+
+PIECE_DEFINITIONS = [
+    [(-1, 0), (0, 0), (1, 0), (2, 0)],
+    [(0, 0), (1, 0), (0, 1), (1, 1)],
+]
+
+class Piece:
+    """A Piece is a group of blocks which are 'alive': 
+    They fall and the player can rotate or move them.
+    A Piece is created with a position, the game, and a list of block_offsets, 
+    each of which represents the location of one of the Piece's 
+    Blocks relative to the Piece position.
+    """
+    name = "piece"
+    display = False
+
+    def __init__(self, position, game, block_offsets):
+        self.position = position
+        self.blocks = {}
+        for offset in block_offsets:
+            self.create_block(game, offset)
+
+    def handle_keystroke(self, keystroke, game):
+        x, y = self.position
+        if keystroke.name == "KEY_LEFT":
+            new_position = (x - 1, y)
+            if self.can_move_to(new_position, game):
+                self.move_to(new_position)
+        elif keystroke.name == "KEY_RIGHT": 
+            new_position = (x + 1, y)
+            if self.can_move_to(new_position, game):
+                self.move_to(new_position)
+
+    def play_turn(self, game):
+        if self.should_fall(game):
+            self.fall(game)
+
+    def should_fall(self, game):
+        """Determines whether the piece should fall.
+        Currently, the Piece falls every third turn. 
+        In the future, the Piece should fall slowly at first, and 
+        then should fall faster at higher levels.
+        """
+        return game.turn_number % 3 == 0
+
+    def fall(self, game):
+        x, y = self.position
+        falling_position = (x, y + 1)
+        if self.can_move_to(falling_position, game):
+            self.move_to(falling_position)
+        else:
+            self.destroy(game)
+
+    def can_move_to(self, new_position, game):
+        """Checks whether the Piece can move to a new position.
+        For every one of the Piece's Blocks, finds where that block
+        would be after the move, and checks whether there are any dead agents
+        already there (live agents would be Blocks which are part of this Piece, 
+        not a problem since they'll be moving too).
+        """
+        x, y = new_position
+        agents_by_position = game.get_agents_by_position()
+        for offset in self.blocks.keys():
+            ox, oy = offset
+            new_block_position = (x+ox, y+oy)
+            if not game.on_board(new_block_position):
+                return False
+            for agent in agents_by_position[new_block_position]:
+                if not agent.alive:
+                    return False
+        return True
+
+    def move_to(self, position):
+        """Move to position and updates positions of Blocks.
+        """
+        x, y = position
+        self.position = position
+        for offset, block in self.blocks.items():
+            ox, oy = offset
+            block.position = (x + ox, y + oy)
+
+    def create_block(self, game, offset):
+        x, y = self.position
+        ox, oy = offset
+        block = Block((x + ox, y + oy))
+        self.blocks[offset] = block
+        game.add_agent(block)
+
+    def destroy(self, game):
+        """Causes the Piece to destroy itself. 
+        All the Blocks are set to dead.
+        """
+        for block in self.blocks.values():
+            block.alive = False
+        game.remove_agent(self)
+        
+
+        
+

poetry.lock

@@ -1,4 +1,4 @@
-# This file is automatically @generated by Poetry 2.0.0 and should not be changed by hand.
+# This file is automatically @generated by Poetry 2.1.3 and should not be changed by hand.
 
 [[package]]
 name = "ansicon"
@@ -48,14 +48,14 @@ ansicon = {version = "*", markers = "platform_system == \"Windows\""}
 
 [[package]]
 name = "retro-games"
-version = "1.1.0"
+version = "1.1.3"
 description = "A simple framework for Terminal-based games"
 optional = false
 python-versions = "<4.0,>=3.10"
 groups = ["main"]
 files = [
-    {file = "retro_games-1.1.0-py3-none-any.whl", hash = "sha256:c621117e4dd528b1e4870d897d00c4365566ab3ba965177e3996ed3c889dd9f8"},
-    {file = "retro_games-1.1.0.tar.gz", hash = "sha256:2167b574f42fe1e739b7c9ec75e98a9b76df42e2166376b85559291b3dc58f82"},
+    {file = "retro_games-1.1.3-py3-none-any.whl", hash = "sha256:4bdd27241b5cb3ee72e69a042d301ff58df2a2ade7e3c29400a538fa54e30148"},
+    {file = "retro_games-1.1.3.tar.gz", hash = "sha256:4f91ff725e551820aa4e30c12c0264e2da41967ed34252122b7136bc2a8ed311"},
 ]
 
 [package.dependencies]