# HG changeset patch
# User Mike Becker <universe@uap-core.de>
# Date 1395836209 -3600
# Node ID 84880c7e1ea611e303f3b999b9a90e20e6db0cf3
# Parent  08d7a6e3ec3140bf09c7b1026c6f784061e68799
interface for retrieving locations when using short algebraic notation
inverted return values of not yet implemented functions to prevent bugs

diff -r 08d7a6e3ec31 -r 84880c7e1ea6 src/game.c
--- a/src/game.c	Sat Mar 22 18:56:52 2014 +0100
+++ b/src/game.c	Wed Mar 26 13:16:49 2014 +0100
@@ -135,8 +135,60 @@
     return result;
 }
 
+/**
+ * Maps a character to a piece.
+ * 
+ * Does not work for pawns, since they don't have a character.
+ * 
+ * @param c one of R,N,B,Q,K
+ * @return numeric value for the specified piece
+ */
+static uint8_t getpiece(char c) {
+    switch (c) {
+        case 'R': return ROOK;
+        case 'N': return KNIGHT;
+        case 'B': return BISHOP;
+        case 'Q': return QUEEN;
+        case 'K': return KING;
+        default: return 0;
+    }
+}
+
+/**
+ * Guesses the location of a piece for short algebraic notation.
+ * 
+ * @param board the current state of the board
+ * @param move the move date to operate on
+ * @return TRUE if the location could be retrieved, FALSE if the location is
+ * ambiguous
+ */
+static _Bool getlocation(Board board, Move *move) {
+    uint8_t piece = move->piece & PIECE_MASK;
+    switch (piece) {
+        case PAWN: return pawn_getlocation(board, move);
+        case ROOK: return rook_getlocation(board, move);
+        case KNIGHT: return knight_getlocation(board, move);
+        case BISHOP: return bishop_getlocation(board, move);
+        case QUEEN: return queen_getlocation(board, move);
+        case KING: return king_getlocation(board, move);
+        default: return FALSE;
+    }
+}
+
+/**
+ * Evaluates a move syntactically and stores the move data in the specified
+ * object.
+ * 
+ * @param board the current state of the board
+ * @param mycolor the color of the current player
+ * @param mstr the input string to parse
+ * @param move a pointer to object where the move data shall be stored
+ * @return TRUE, if the move is syntactically valid, FALSE otherwise
+ */
 static _Bool eval_move(Board board, uint8_t mycolor, char *mstr, Move *move) {
     memset(move, 0, sizeof(Move));
+    move->fromfile = POS_UNSPECIFIED;
+    move->fromrow = POS_UNSPECIFIED;
     
     size_t len = strlen(mstr);
     
@@ -152,22 +204,22 @@
     if (len == 2) {
         /* pawn move (e.g. "e4") */
         if (isfile(mstr[0]) && isrow(mstr[1])) {
-            move->piece = PAWN|mycolor;
+            move->piece = PAWN;
             move->tofile = fileidx(mstr[0]);
             move->torow = rowidx(mstr[1]);
-            if (!pawn_getlocation(board, move)) {
-                move->piece = 0;
-            }
         }
     } else if (len == 3) {
         if (strcmp(mstr, "O-O") == 0) {
             /* king side castling */
-            move->piece = KING|mycolor;
+            move->piece = KING;
             move->fromfile = fileidx('e');
             move->tofile = fileidx('g');
             move->fromrow = move->torow = mycolor == WHITE ? 0 : 7;
         } else {
             /* unambiguous move (e.g. "Nf3") */
+            move->piece = getpiece(mstr[0]);
+            move->tofile = isfile(mstr[1]) ? fileidx(mstr[1]) : POS_UNSPECIFIED;
+            move->torow = isrow(mstr[2]) ? fileidx(mstr[2]) : POS_UNSPECIFIED;
         }
         
     } else if (len == 4) {
@@ -178,7 +230,7 @@
     } else if (len == 5) {
         if (strcmp(mstr, "O-O-O") == 0) {
             /* queen side castling "O-O-O" */
-            move->piece = KING|mycolor;
+            move->piece = KING;
             move->fromfile = fileidx('e');
             move->tofile = fileidx('c');
             move->fromrow = move->torow = mycolor == WHITE ? 0 : 7;
@@ -192,6 +244,15 @@
     } else if (len == 6) {
         /* long notation capture (e.g. "Nc5xf3") */
     }
+
+    if (move->piece) {
+        move->piece |= mycolor;
+    }
+    
+    if (!getlocation(board, move)) {
+        // TODO: return status code to indicate the error type
+        move->piece = 0;
+    }
     
     return move->piece != 0;
 }
diff -r 08d7a6e3ec31 -r 84880c7e1ea6 src/game.h
--- a/src/game.h	Sat Mar 22 18:56:52 2014 +0100
+++ b/src/game.h	Wed Mar 26 13:16:49 2014 +0100
@@ -76,6 +76,8 @@
     _Bool capture;
 } Move;
 
+#define POS_UNSPECIFIED UINT8_MAX
+
 #define isfile(file) (file >= 'a' && file <= 'h')
 #define isrow(row) (row >= '1' && row <= '8')
 #define rowidx(row) (row-'1')
diff -r 08d7a6e3ec31 -r 84880c7e1ea6 src/rules/bishop.c
--- a/src/rules/bishop.c	Sat Mar 22 18:56:52 2014 +0100
+++ b/src/rules/bishop.c	Wed Mar 26 13:16:49 2014 +0100
@@ -31,15 +31,15 @@
 
 _Bool bishop_chkrules(Board board, Move* move) {
     // TODO: implement
-    return TRUE;
+    return FALSE;
 }
 
 _Bool bishop_isblocked(Board board, Move *move) {
     // TODO: implement
-    return FALSE;
+    return TRUE;
 }
 
 _Bool bishop_getlocation(Board board, Move *move) {
     // TODO: implement
-    return TRUE;
+    return FALSE;
 }
diff -r 08d7a6e3ec31 -r 84880c7e1ea6 src/rules/king.c
--- a/src/rules/king.c	Sat Mar 22 18:56:52 2014 +0100
+++ b/src/rules/king.c	Wed Mar 26 13:16:49 2014 +0100
@@ -31,15 +31,15 @@
 
 _Bool king_chkrules(Board board, Move* move) {
     // TODO: implement
-    return TRUE;
+    return FALSE;
 }
 
 _Bool king_isblocked(Board board, Move *move) {
     // TODO: implement
-    return FALSE;
+    return TRUE;
 }
 
 _Bool king_getlocation(Board board, Move *move) {
     // TODO: implement
-    return TRUE;
+    return FALSE;
 }
diff -r 08d7a6e3ec31 -r 84880c7e1ea6 src/rules/knight.c
--- a/src/rules/knight.c	Sat Mar 22 18:56:52 2014 +0100
+++ b/src/rules/knight.c	Wed Mar 26 13:16:49 2014 +0100
@@ -31,15 +31,15 @@
 
 _Bool knight_chkrules(Board board, Move *move) {
     // TODO: implement
-    return TRUE;
+    return FALSE;
 }
 
 _Bool knight_isblocked(Board board, Move *move) {
     // TODO: implement
-    return FALSE;
+    return TRUE;
 }
 
 _Bool knight_getlocation(Board board, Move *move) {
     // TODO: implement
-    return TRUE;
+    return FALSE;
 }
diff -r 08d7a6e3ec31 -r 84880c7e1ea6 src/rules/pawn.c
--- a/src/rules/pawn.c	Sat Mar 22 18:56:52 2014 +0100
+++ b/src/rules/pawn.c	Wed Mar 26 13:16:49 2014 +0100
@@ -42,6 +42,8 @@
 _Bool pawn_getlocation(Board board, Move *move) {
     int8_t d = ((move->piece & COLOR_MASK) == WHITE ? -1 : 1);
     
+    // TODO: battle moves
+    
     move->fromfile = move->tofile;
     move->fromrow = move->torow + d;
     if (move->fromrow > 6) {
diff -r 08d7a6e3ec31 -r 84880c7e1ea6 src/rules/queen.c
--- a/src/rules/queen.c	Sat Mar 22 18:56:52 2014 +0100
+++ b/src/rules/queen.c	Wed Mar 26 13:16:49 2014 +0100
@@ -31,15 +31,15 @@
 
 _Bool queen_chkrules(Board board, Move* move) {
     // TODO: implement
-    return TRUE;
+    return FALSE;
 }
 
 _Bool queen_isblocked(Board board, Move *move) {
     // TODO: implement
-    return FALSE;
+    return TRUE;
 }
 
 _Bool queen_getlocation(Board board, Move *move) {
     // TODO: implement
-    return TRUE;
+    return FALSE;
 }
diff -r 08d7a6e3ec31 -r 84880c7e1ea6 src/rules/rook.c
--- a/src/rules/rook.c	Sat Mar 22 18:56:52 2014 +0100
+++ b/src/rules/rook.c	Wed Mar 26 13:16:49 2014 +0100
@@ -31,15 +31,15 @@
 
 _Bool rook_chkrules(Board board, Move *move) {
     // TODO: implement
-    return TRUE;
+    return FALSE;
 }
 
 _Bool rook_isblocked(Board board, Move *move) {
     // TODO: implement
-    return FALSE;
+    return TRUE;
 }
 
 _Bool rook_getlocation(Board board, Move *move) {
     // TODO: implement
-    return TRUE;
+    return FALSE;
 }