implemented conveyor board elements, paying attention to conflicts and order of execution

roborally.py

@@ -89,16 +89,25 @@ class Robot:
         # mark the tile on the board as occupied
         self.board[(x,y)].occupant = self
 
+    def get_tile(self):
+        # return the tile the robot is standing on
+        return self.board[(self.x, self.y)]
+
+    def get_adjecent_tile(self, direction):
+        # get the tile adjecent to the robot in the given direction
+        current_tile = self.get_tile()
+        return self.board[current_tile.get_neighbor_coordinates(direction)]
 
     def get_accessed_tiles(self, count, forward=True):
         # create a list of all tiles the robot would enter if it drives <count> steps forward
         tiles = []
-        current_tile = self.board[(self.x, self.y)]
+        current_tile = self.get_tile()
         for i in range(1, count + 1):
             if forward:
                 current_tile = self.board.get(current_tile.get_neighbor_coordinates(self.orientation))
             else:
                 current_tile = self.board.get(current_tile.get_neighbor_coordinates(Robot.opposites[self.orientation]))
+
             if current_tile is None:
                 return tiles
             else:
@@ -108,7 +117,7 @@ class Robot:
     def is_pushable(self, direction):
         # check if the robot can be pushed in the given direction
         # this is the case if there is a non-blocking tile next to the robot or if there is another robot that is pushable
-        robot_tile = self.board[(self.x, self.y)]
+        robot_tile = self.get_tile()
         neighbor_tile = self.board.get(robot_tile.get_neighbor_coordinates(direction))
         if neighbor_tile is None:   # neighbor tile could not be found -> robot would be pushed out of the board
             return False
@@ -140,9 +149,9 @@ class Robot:
     def move(self, type):
         # move the robot forward or backward
         # this involves
-        tile = self.board[(self.x, self.y)]
+        tile = self.get_tile()
         if type == 'forward':
-            target_tile = self.board[tile.get_neighbor_coordinates(self.orientation)]
+            target_tile = self.get_adjecent_tile(self.orientation)
 
             if target_tile.occupant is not None:
                 print("error: target tile is not empty")
@@ -157,7 +166,7 @@ class Robot:
             return "{}, forward".format(self.id)
         elif type == 'backward':
             opposite_orientation = self.get_opposite_orientation()
-            target_tile = self.board[tile.get_neighbor_coordinates(opposite_orientation)]
+            target_tile = self.get_adjecent_tile(opposite_orientation)
 
             if target_tile.occupant is not None:
                 print("error: target tile is not empty")
@@ -178,6 +187,19 @@ class Robot:
         # do nothing command
         return "{}, nop".format(self.id)
 
+    def board_element_processable(self):
+        # check if we can directly process the board element for the tile the current robot is located on
+        tile = self.get_tile()
+
+        if tile.modifier is None:
+            return True
+        elif tile.modifier in ['^', '>', 'v', '<']:
+            direction = tile.modifier
+            neighbor_tile = self.get_adjecent_tile(direction)
+            return neighbor_tile.occupant is None   # if the adjacent tile the robot will be pushed into is empty
+                                                    # we can execute the push
+        return True
+
     def __str__(self):
         return str(self.id)
 
@@ -242,12 +264,23 @@ class Board:
                     self.board[(x, y)] = Tile(x, y, 'v')
                 elif y == 4:
                     self.board[(x, y)] = Tile(x, y, '>')
+                elif y == 1 and (x >= 2) and (x < 5):
+                    self.board[(x, y)] = Tile(x, y, '>')
+                elif y == 1 and (x >= 6) and (x <= 8):
+                    self.board[(x, y)] = Tile(x, y, '<')
                 else:
                     self.board[(x,y)] = Tile(x,y)
 
+        self.board[(1, 1)].modifier = 'v'
+        self.board[(1, 2)].modifier = '>'
+        self.board[(2, 2)].modifier = '^'
+        self.board[(2, 1)].modifier = '<'
+
         self.robots = {}
-        self.robots[0] = Robot(3, 1, '>', 0, self.board)
+        self.robots[0] = Robot(1, 1, '>', 0, self.board)
-        self.robots[1] = Robot(2, 1, 'v', 1, self.board)
+        self.robots[1] = Robot(1, 2, 'v', 1, self.board)
+        self.robots[2] = Robot(2, 1, '>', 2, self.board)
+        self.robots[3] = Robot(2, 2, 'v', 3, self.board)
 
     def handle_push(self, direction, pushed_robot, forward=True, pushing_robot=None):
         cmd_list = []
@@ -392,14 +425,57 @@ class Board:
 
                 cmd_list += self.handle_single_action(action, robot)
 
-            # apply the actions caused by board elements at the end of the phase
-            for robot_id in self.robots:
-                robot = self.robots[robot_id]
-                cmd_list += self.handle_board_element(robot)
-
-            print(cmd_list)
             print(self)
-            pass
+
+            # apply the actions caused by board elements at the end of the phase
+            self.apply_board_element_actions()
+
+            return cmd_list
+
+    def apply_board_element_actions(self):
+        cmd_list = []
+        remaining_robots = set(self.robots.values())
+        processed_robots = set()
+
+        # first we compute all tiles the robots would enter as a result of board game elements
+        target_tiles = {}  # get target tiles for each robot
+        for r in remaining_robots:
+            tile = r.get_tile()
+            if tile.modifier in ['^', '>', 'v', '<']:  # tile would push the robot around
+                direction = tile.modifier
+                target_tiles[r] = r.get_adjecent_tile(direction)  # save tile the robot would be pushed to
+
+        # now we check if there are any conflicts
+        conflicting_tiles = set([x for x in target_tiles.values() if list(target_tiles.values()).count(x) > 1])
+        if len(conflicting_tiles) > 0:  # check if any robots would be pushed to the same tile
+            # there is a conflict -> skip the board element execution and mark those robots as processed
+            conflicting_robots = set(filter(lambda r: target_tiles[r] in conflicting_tiles, target_tiles.keys()))
+            processed_robots = processed_robots.union(conflicting_robots)
+
+        # Now we process the board game elements for the robots which have no conflicts.
+        # We have to pay attention to the order of the execution in order to avoid robots pushing other robots
+        # during this phase.
+        # This is done in a loop because we don't know yet which robot goes first. For instance, it may happen that
+        # multiple robots are queued on a conveyor belt. Then we first have to move the robot which is furthest down the
+        # line, then the second one and so on
+        # By doing this in a loop we can automatically determine the correct order by checking for each robot if it can
+        # move and then processing the robot such that the next robot can move
+        while len(processed_robots) < len(self.robots):
+            # update remaining robots to process
+            remaining_robots = set(self.robots.values()) - processed_robots
+
+            # check which robots can be moved around
+            processable_robots = list(filter(lambda r: r.board_element_processable(), remaining_robots))
+
+            if len(processable_robots) > 0:
+                # handle the board game elements for robots that can move
+                for current_robot in processable_robots:
+                    cmd_list += self.handle_board_element(current_robot)
+                    processed_robots.add(current_robot)
+            else:
+                # this happens if there is a deadlock that cannot be resolved (e.g. caused by a cyclical conveyor belt)
+                break
+
         return cmd_list
 
     def __str__(self):
@@ -421,7 +497,7 @@ if __name__ == "__main__":
 
     deck = CardDeck()
 
-    player_1_cards = random.sample(list(filter(lambda c: 'backward' in c.action, deck.deck.values())), n)
+    player_1_cards = random.sample(list(filter(lambda c: 'turn around' in c.action, deck.deck.values())), n)
     player_2_cards = random.sample(list(filter(lambda c: 'turn around' in c.action, deck.deck.values())), n)
     #player_1_cards = deck.draw_cards(40)
     #player_2_cards = deck.draw_cards(40)
@@ -429,7 +505,15 @@ if __name__ == "__main__":
     cards_1 = [(0, c) for c in player_1_cards]
     cards_2 = [(1, c) for c in player_2_cards]
 
-    chosen_cards = list(zip(cards_1, cards_2))
+    player_3_cards = random.sample(list(filter(lambda c: 'turn around' in c.action, deck.deck.values())), n)
+    player_4_cards = random.sample(list(filter(lambda c: 'turn around' in c.action, deck.deck.values())), n)
+    #player_1_cards = deck.draw_cards(40)
+    #player_2_cards = deck.draw_cards(40)
+
+    cards_3 = [(0, c) for c in player_3_cards]
+    cards_4 = [(1, c) for c in player_4_cards]
+
+    chosen_cards = list(zip(cards_1, cards_2, cards_3, cards_4))
 
     b = Board()
     print(b)