Added parameter to get_board_visual to see the board from black's poi…

…nt of view (#104)

README.md

@@ -208,6 +208,30 @@ stockfish.get_board_visual()
 +---+---+---+---+---+---+---+---+
   a   b   c   d   e   f   g   h
 ```
+This function has an optional boolean (True by default) as a parameter that indicates whether the board should be seen from the view of white. So it is possible to get the board from black's point of view like this:
+```python 
+stockfish.get_board_visual(False)
+```
+```text
++---+---+---+---+---+---+---+---+
+| R | N | B | K | Q | B | N | R | 1
++---+---+---+---+---+---+---+---+
+| P | P | P | P | P | P | P | P | 2
++---+---+---+---+---+---+---+---+
+|   |   |   |   |   |   |   |   | 3
++---+---+---+---+---+---+---+---+
+|   |   |   |   |   |   |   |   | 4
++---+---+---+---+---+---+---+---+
+|   |   |   |   |   |   |   |   | 5
++---+---+---+---+---+---+---+---+
+|   |   |   |   |   |   |   |   | 6
++---+---+---+---+---+---+---+---+
+| p | p | p | p | p | p | p | p | 7
++---+---+---+---+---+---+---+---+
+| r | n | b | k | q | b | n | r | 8
++---+---+---+---+---+---+---+---+
+  h   g   f   e   d   c   b   a
+```
 
 ### Get current board evaluation in centipawns or mate in x
 ```python 

stockfish/models.py

@@ -222,28 +222,48 @@ def make_moves_from_current_position(self, moves: List[str]) -> None:
             f"position fen {self.get_fen_position()} moves {self._convert_move_list_to_str(moves)}"
         )
 
-    def get_board_visual(self) -> str:
+    def get_board_visual(self, perspective_white: bool = True) -> str:
         """Returns a visual representation of the current board position.
 
+        Args:
+            perspective_white:
+              A bool that indicates whether the board should be displayed from the
+              perspective of white (True: white, False: black)
+
         Returns:
             String of visual representation of the chessboard with its pieces in current position.
         """
         self._put("d")
-        board_rep = ""
+        board_rep_lines = []
         count_lines = 0
         while count_lines < 17:
             board_str = self._read_line()
             if "+" in board_str or "|" in board_str:
                 count_lines += 1
-                board_rep += f"{board_str}\n"
+                if perspective_white:
+                    board_rep_lines.append(f"{board_str}")
+                else:
+                    # If the board is to be shown from black's point of view, all lines are
+                    # inverted horizontally and at the end the order of the lines is reversed.
+                    board_part = board_str[:33]
+                    # To keep the displayed numbers on the right side,
+                    # only the string representing the board is flipped.
+                    number_part = board_str[33:] if len(board_str) > 33 else ""
+                    board_rep_lines.append(f"{board_part[::-1]}{number_part}")
+        if not perspective_white:
+            board_rep_lines = board_rep_lines[::-1]
         board_str = self._read_line()
         if "a   b   c" in board_str:
             # Engine being used is recent enough to have coordinates, so add them:
-            board_rep += f"  {board_str}\n"
+            if perspective_white:
+                board_rep_lines.append(f"  {board_str}")
+            else:
+                board_rep_lines.append(f"  {board_str[::-1]}")
         while "Checkers" not in self._read_line():
             # Gets rid of the remaining lines in _stockfish.stdout.
             # "Checkers" is in the last line outputted by Stockfish for the "d" command.
             pass
+        board_rep = "\n".join(board_rep_lines) + "\n"
         return board_rep
 
     def get_fen_position(self) -> str:

tests/stockfish/test_models.py

@@ -297,7 +297,7 @@ def test_chess960_position(self, stockfish):
         assert stockfish.get_evaluation() == {"type": "mate", "value": 1}
         assert stockfish.will_move_be_a_capture("f1g1") is Stockfish.Capture.NO_CAPTURE
 
-    def test_get_board_visual(self, stockfish):
+    def test_get_board_visual_white(self, stockfish):
         stockfish.set_position(["e2e4", "e7e6", "d2d4", "d7d5"])
         if stockfish.get_stockfish_major_version() >= 12:
             expected_result = (
@@ -349,6 +349,58 @@ def test_get_board_visual(self, stockfish):
         # Tests that the previous call to get_board_visual left no remaining lines to be read. This means
         # the second line read after stockfish._put("d") now will be the +---+---+---+ of the new outputted board.
 
+    def test_get_board_visual_black(self, stockfish):
+        stockfish.set_position(["e2e4", "e7e6", "d2d4", "d7d5"])
+        if stockfish.get_stockfish_major_version() >= 12:
+            expected_result = (
+                "+---+---+---+---+---+---+---+---+\n"
+                "| R | N | B | K | Q | B | N | R | 1\n"
+                "+---+---+---+---+---+---+---+---+\n"
+                "| P | P | P |   |   | P | P | P | 2\n"
+                "+---+---+---+---+---+---+---+---+\n"
+                "|   |   |   |   |   |   |   |   | 3\n"
+                "+---+---+---+---+---+---+---+---+\n"
+                "|   |   |   | P | P |   |   |   | 4\n"
+                "+---+---+---+---+---+---+---+---+\n"
+                "|   |   |   |   | p |   |   |   | 5\n"
+                "+---+---+---+---+---+---+---+---+\n"
+                "|   |   |   | p |   |   |   |   | 6\n"
+                "+---+---+---+---+---+---+---+---+\n"
+                "| p | p | p |   |   | p | p | p | 7\n"
+                "+---+---+---+---+---+---+---+---+\n"
+                "| r | n | b | k | q | b | n | r | 8\n"
+                "+---+---+---+---+---+---+---+---+\n"
+                "  h   g   f   e   d   c   b   a\n"
+            )
+        else:
+            expected_result = (
+                "+---+---+---+---+---+---+---+---+\n"
+                "| R | N | B | K | Q | B | N | R |\n"
+                "+---+---+---+---+---+---+---+---+\n"
+                "| P | P | P |   |   | P | P | P |\n"
+                "+---+---+---+---+---+---+---+---+\n"
+                "|   |   |   |   |   |   |   |   |\n"
+                "+---+---+---+---+---+---+---+---+\n"
+                "|   |   |   | P | P |   |   |   |\n"
+                "+---+---+---+---+---+---+---+---+\n"
+                "|   |   |   |   | p |   |   |   |\n"
+                "+---+---+---+---+---+---+---+---+\n"
+                "|   |   |   | p |   |   |   |   |\n"
+                "+---+---+---+---+---+---+---+---+\n"
+                "| p | p | p |   |   | p | p | p |\n"
+                "+---+---+---+---+---+---+---+---+\n"
+                "| r | n | b | k | q | b | n | r |\n"
+                "+---+---+---+---+---+---+---+---+\n"
+            )
+
+        assert stockfish.get_board_visual(False) == expected_result
+
+        stockfish._put("d")
+        stockfish._read_line()  # skip a line
+        assert "+---+---+---+" in stockfish._read_line()
+        # Tests that the previous call to get_board_visual left no remaining lines to be read. This means
+        # the second line read after stockfish._put("d") now will be the +---+---+---+ of the new outputted board.
+
     def test_get_fen_position(self, stockfish):
         assert (
             stockfish.get_fen_position()