[Chess System Extension] Chess960 Things

Monika After Story/game/chess.rpy

@@ -31,11 +31,6 @@ default persistent._mas_chess_mangle_all = False
 # skip file checks
 default persistent._mas_chess_skip_file_checks = False
 
-define mas_chess.CHESS_SAVE_PATH = "/chess_games/"
-define mas_chess.CHESS_SAVE_EXT = ".pgn"
-define mas_chess.CHESS_SAVE_NAME = "abcdefghijklmnopqrstuvwxyz ABCDEFGHIJKLMNOPQRSTUVWXYZ-_0123456789"
-define mas_chess.CHESS_PROMPT_FORMAT = "{0} | {1} | Turn: {2} | You: {3}"
-
 # mass chess store
 init python in mas_chess:
     import os
@@ -44,6 +39,16 @@ init python in mas_chess:
     import store
     import random
 
+    CHESS_SAVE_PATH = "/chess_games/"
+    CHESS_SAVE_EXT = ".pgn"
+    CHESS_SAVE_NAME = "abcdefghijklmnopqrstuvwxyz ABCDEFGHIJKLMNOPQRSTUVWXYZ-_0123456789"
+    CHESS_PROMPT_FORMAT = "{0} | {1} | Turn: {2} | You: {3}"
+
+    #chess modes
+    MODE_NORMAL = "normal_chess"
+    MODE_BAD_CHESS = "chess960"
+    MODE_960 = "badchess"
+
     # relative chess directory
     REL_DIR = "chess_games/"
 
@@ -312,7 +317,7 @@ init python in mas_chess:
         #Otherwise, since we can't afford to expend more, we just get pawns
         return 'p'
 
-    def gen_side(white=True, max_side_value=14):
+    def _gen_side(white=True, max_side_value=14):
         """
         Generates a player's side
 
@@ -466,7 +471,7 @@ init python in mas_chess:
 
         return white_is_good and black_is_good
 
-    def generate_fen(is_player_white=True):
+    def generate_random_fen(is_player_white=True):
         """
         Generates a random fen
 
@@ -498,8 +503,8 @@ init python in mas_chess:
             and attempts < 10
         ):
             attempts += 1
-            player_first_row, player_second_row = gen_side(is_player_white, max_piece_value)
-            monika_first_row, monika_second_row = gen_side(not is_player_white, monika_max_piece_value)
+            player_first_row, player_second_row = _gen_side(is_player_white, max_piece_value)
+            monika_first_row, monika_second_row = _gen_side(not is_player_white, monika_max_piece_value)
 
             if is_player_white:
                 white_front = player_first_row
@@ -532,6 +537,73 @@ init python in mas_chess:
                 white_pieces_back=monika_second_row
             )
 
+    def generate_960_fen():
+        """
+        This function returns a random chess960 opening fen.
+
+        Chess960 rules are basically:
+        1. One rook must stay on the left side of king, and another one stay on the right side.
+           Due to this, the king can never be placed on a-file or h-file.
+        2. Bishops must stay on different color square.
+        3. Pawns must stay like the normal chess game.
+        4. The position of player A's pieces must be the 'reversed version' of player B's.
+        See chess960 wiki to get more exact information.
+
+        OUT:
+            A random chess960 opening fen.
+        """
+        #Gen king pos (cannot be on the outer squares)
+        king_position = random.randint(1, 6)
+
+        #Now gen rook positions
+        left_rook_position = random.randint(0, king_position-1)
+        right_rook_position = random.randint(king_position+1, 7)
+
+        #Now, we generate the remaining available range
+        occupied_positions = frozenset((king_position, left_rook_position, right_rook_position))
+        # FIXME: Due to a renpy bug, we have to access python set here via _set
+        # In the latest versions it might be fixed, so this should be adjusted w/ r7 support
+        available_white_positions = _set(range(1, 9, 2)) - occupied_positions
+        available_black_positions = _set(range(0, 8, 2)) - occupied_positions
+
+        #For picking bishops, we need to have one on a light square, one on a dark square
+        first_bishop_position = random.choice(tuple(available_white_positions))
+        second_bishop_position = random.choice(tuple(available_black_positions))
+        if bool(random.randint(0, 1)):
+            first_bishop_position, second_bishop_position = second_bishop_position, first_bishop_position
+
+        occupied_positions = frozenset((first_bishop_position, second_bishop_position))
+        available_positions = (available_white_positions | available_black_positions) - occupied_positions
+
+        #Queen can be anywhere remaining
+        queen_position = random.choice(tuple(available_positions))
+        available_positions.remove(queen_position)
+
+        #Finally, unpack for knights
+        first_knight_position, second_knight_position = available_positions
+
+        #Now that we have positions, we should format them for easy conversion to a FEN
+        pos_to_piece_map = {
+            king_position: "K",
+            left_rook_position: "R",
+            right_rook_position: "R",
+            first_bishop_position: "B",
+            second_bishop_position: "B",
+            queen_position: "Q",
+            first_knight_position: "N",
+            second_knight_position: "N"
+        }
+
+        back_row_str = "".join(pos_to_piece_map[i] for i in range(8))
+
+        # Finally. Now return a full fen.
+        return BASE_FEN.format(
+            black_pieces_back=back_row_str.lower(),
+            black_pieces_front="pppppppp",
+            white_pieces_front="PPPPPPPP",
+            white_pieces_back=back_row_str
+        )
+
     def enqueue_output(out, queue, lock):
         for line in iter(out.readline, b''):
             with lock:
@@ -551,7 +623,7 @@ label game_chess:
         failed_to_load_save = True
 
         #Prelim definitions of the rules for the menu later
-        do_really_bad_chess = False
+        chessmode = mas_chess.MODE_NORMAL
         casual_rules = False
         practice_mode = False
         is_player_white = 0
@@ -649,7 +721,6 @@ label game_chess:
                     #These also override the base settings as to play a continuation
                     practice_mode = eval(loaded_game.headers.get("Practice", "False"))
                     casual_rules = eval(loaded_game.headers.get("CasualRules", "False"))
-                    do_really_bad_chess = loaded_game.headers["FEN"] != MASChessDisplayableBase.START_FEN
 
                 jump mas_chess_start_chess
 
@@ -788,7 +859,6 @@ label game_chess:
             #These also override the base settings as to play a continuation
             practice_mode = eval(loaded_game.headers.get("Practice", "False"))
             casual_rules = eval(loaded_game.headers.get("CasualRules", "False"))
-            do_really_bad_chess = loaded_game.headers["FEN"] != MASChessDisplayableBase.START_FEN
 
         jump mas_chess_start_chess
 
@@ -799,8 +869,9 @@ label mas_chess_remenu:
         menu_contents = {
             "gamemode_select": {
                 "options": [
-                    ("Normal Chess", False, False, not do_really_bad_chess),
-                    ("Randomized Chess", True, False, do_really_bad_chess)
+                    ("Normal Chess", mas_chess.MODE_NORMAL, False, (chessmode is mas_chess.MODE_NORMAL)),
+                    ("Randomized Chess", mas_chess.MODE_BAD_CHESS, False, (chessmode is mas_chess.MODE_BAD_CHESS)),
+                    ("Chess 960", mas_chess.MODE_960, False, (chessmode is mas_chess.MODE_960))
                 ],
                 "final_items": [
                     ("Ruleset", "ruleset_select", False, False, 20),
@@ -858,11 +929,11 @@ label mas_chess_remenu:
     $ menu_options = menu_contents[menu_category]["options"]
     $ final_items = menu_contents[menu_category]["final_items"]
 
+    m "How would you like to play?[('{fast}' if loopback else '')]" nointeract
+
     #Now we show menu
     call screen mas_gen_scrollable_menu(menu_options, mas_ui.SCROLLABLE_MENU_TXT_MEDIUM_AREA, mas_ui.SCROLLABLE_MENU_XALIGN, *final_items)
 
-    $ renpy.say(m, "How would you like to play?{0}".format("{fast}" if loopback else ""), interact=False)
-
     $ loopback = True
 
     #We're quitting out
@@ -883,9 +954,9 @@ label mas_chess_remenu:
     elif _return not in ("confirm", None):
         $ _history_list.pop()
 
-        #Normal/Really Bad Chess selection
+        #Normal/Really Bad Chess/Chess 960 selection
         if menu_category == "gamemode_select":
-            $ do_really_bad_chess = _return
+            $ chessmode = _return
 
         #Practice/Play mode
         elif menu_category == "ruleset_select":
@@ -923,7 +994,13 @@ label mas_chess_remenu:
 
 label mas_chess_start_chess:
     #Setup the chess FEN
-    $ starting_fen = mas_chess.generate_fen(is_player_white) if do_really_bad_chess else None
+    python:
+        if chessmode == mas_chess.MODE_NORMAL:
+            starting_fen = None
+        elif chessmode == mas_chess.MODE_960:
+            starting_fen = mas_chess.generate_960_fen()
+        else:
+            starting_fen = mas_chess.generate_random_fen(is_player_white)
 
     #NOTE: This is a failsafe in case people jump to the mas_chess_start_chess label
     if persistent._mas_chess_timed_disable is not None:
@@ -1238,7 +1315,6 @@ label mas_chess_savegame(silent=False, allow_return=True):
             m 1eub "Let's continue this game soon!"
     return
 
-
 label mas_chess_locked_no_play:
     m 1euc "No thanks, [player]."
     m 1rsc "I don't really feel like playing chess right now."