Make SAN case sensitive, add ability to specify from to squares

moves that specify the b column get confused with the symbol for
a bishop. More regex magic required for case insensitivity

src/lx_chess.cr

@@ -33,7 +33,9 @@ end
 
 log = [] of String
 fen = LxChess::Fen.parse(options["fen_string"])
-game = LxChess::Game.new(board: fen.board)
+player_white = LxChess::Player.new
+player_black = LxChess::Player.new
+game = LxChess::Game.new(board: fen.board, players: [player_white, player_black])
 gb = LxChess::TermBoard.new(game.board)
 term = LxChess::Terminal.new
 
@@ -74,6 +76,22 @@ loop do
       from + to
     end.compact.join(" | ")
     log.unshift move_string
+  when /\s*([a-z]\d)\s*([a-z]\d)\s*(?:=\s*)?([RNBQ])?/i
+    if input
+      if matches = input.downcase.match(/\s*([a-z]\d)\s*([a-z]\d)\s*(?:=\s*)?([RNBQ])?/i)
+        from = matches[1]
+        to = matches[2]
+        promo = if matches[3]?
+                  matches[3][0]
+                end
+        if from && to
+          gb.clear
+          san = game.make_move(from, to)
+          gb.highlight([game.board.index(from), game.board.index(to)])
+          log.unshift "#{san.to_s}: #{from} => #{to}"
+        end
+      end
+    end
   when nil
   else
     if input
@@ -81,10 +99,9 @@ loop do
       from, to = game.parse_san(notation)
       if from && to
         gb.clear
-        piece = game.board.move(from, to)
-        game.next_turn
+        san = game.make_move(from, to)
         gb.highlight([from.to_i16, to.to_i16])
-        log.unshift "#{notation.to_s}: #{game.board.cord(from)} => #{game.board.cord(to)}"
+        log.unshift "#{san.to_s}: #{game.board.cord(from)} => #{game.board.cord(to)}"
       end
     end
   end

src/lx_chess/game.cr

@@ -20,11 +20,6 @@ module LxChess
       @en_passant_target = @board.index(cord)
     end
 
-    def next_turn
-      @turn = (@turn == 0 ? 1 : 0).to_i8
-      @move_clock += 1
-    end
-
     def full_moves
       (@move_clock / 2).to_i16
     end
@@ -53,7 +48,8 @@ module LxChess
       end
     end
 
-    def move_to_san(from : Int16, to : Int16, promotion : String? = nil)
+    # TODO: add check, checkmate, etc.
+    def move_to_san(from : Int, to : Int, promotion : String? = nil)
       raise "No piece at #{@board.cord(from)}" unless piece = @board[from]
       en_passant = piece.pawn? && to == @en_passant_target
 
@@ -155,5 +151,22 @@ module LxChess
         set
       end
     end
+
+    def make_move(from : String, to : String, promotion : Char? = nil)
+      make_move(from: @board.index(from), to: @board.index(to), promotion: promotion)
+    end
+
+    def make_move(from : Int, to : Int, promotion : Char? = nil)
+      san = move_to_san(from, to, promotion)
+      piece = @board.move(from, to)
+      next_turn
+      san
+    end
+
+    def next_turn
+      @turn += 1
+      @turn = @turn % @players.size
+      @move_clock += 1
+    end
   end
 end

src/lx_chess/notation.cr

@@ -19,22 +19,22 @@ module LxChess
       (\+)?\s*                                   # 8.  check
       (\#)?\s*                                   # 9.  checkmate
       (e\.?p\.?)?\s*                             # 10. en passant
-    \z}ix
+    \z}x
 
     @match : Regex::MatchData?
 
-    property square : String?,
-      castles_k : Bool,
-      castles_q : Bool,
-      en_passant : Bool,
-      check : Bool,
-      checkmate : Bool,
-      takes : Bool,
-      piece_abbr : Char?,
-      origin : String?,
-      promotion : Char?,
-      from : String?,
-      to : String?
+    property square : String?
+    property castles_k : Bool
+    property castles_q : Bool
+    property en_passant : Bool
+    property check : Bool
+    property checkmate : Bool
+    property takes : Bool
+    getter piece_abbr : Char?
+    property origin : String?
+    property promotion : Char?
+    property from : String?
+    property to : String?
 
     def initialize(notation : String)
       unless match = notation.match(NOTATION_REGEX)
@@ -83,7 +83,7 @@ module LxChess
       @from = nil,
       @to = nil
     )
-      @piece_abbr = "K" if @castles_q || @castles_k
+      @piece_abbr = 'K' if @castles_q || @castles_k
       validate
     end
 
@@ -92,6 +92,12 @@ module LxChess
       raise InvalidMove.new("Cannot capture while castling") if castles? && takes?
     end
 
+    def piece_abbr
+      if abbr = @piece_abbr
+        abbr.upcase
+      end
+    end
+
     def en_passant?
       @en_passant
     end
@@ -146,7 +152,7 @@ module LxChess
       when castles_q?
         "O-O-O"
       else
-        @piece_abbr
+        piece_abbr != 'P' || @takes ? piece_abbr : nil
       end
 
       if @en_passant

src/lx_chess/piece.cr

@@ -48,5 +48,9 @@ module LxChess
     def fen_symbol
       FEN_SYMBOLS[@id]
     end
+
+    def pawn?
+      @id & 0b0111 == PAWN
+    end
   end
 end

src/lx_chess/player.cr

@@ -1,4 +1,7 @@
 module LxChess
+  property castle_left = true
+  property castle_right = true
+
   class Player
   end
 end