# HG changeset patch
# User Mike Becker <universe@uap-core.de>
# Date 1396003501 -3600
# Node ID 7ffd66591afef09dd9710fb19718376839d40b05
# Parent  970748b9a73b8d3f9a22fc9bf109423094aa94ed
completed pawn rules + bug fixes for 4-char-moves

diff -r 970748b9a73b -r 7ffd66591afe src/game.c
--- a/src/game.c	Wed Mar 26 14:53:15 2014 +0100
+++ b/src/game.c	Fri Mar 28 11:45:01 2014 +0100
@@ -78,14 +78,35 @@
  * @param move the move to apply
  */
 static void apply_move(Board board, Move *move) {
+    uint8_t piece = move->piece & PIECE_MASK;
+    uint8_t color = move->piece & COLOR_MASK;
+    
+    /* en passant capture */
+    if (move->capture && piece == PAWN &&
+        mdst(board, move) == 0) {
+        board[move->fromrow][move->tofile] = 0;
+    }
+    
+    /* remove old en passant threats */
+    for (uint8_t file = 0 ; file < 8 ; file++) {
+        board[3][file] &= ~ENPASSANT_THREAT;
+        board[4][file] &= ~ENPASSANT_THREAT;
+    }
+    
+    /* add new en passant threat */
+    if (piece == PAWN && (
+        (move->fromrow == 1 && move->torow == 3) ||
+        (move->fromrow == 6 && move->torow == 4))) {
+        move->piece |= ENPASSANT_THREAT;
+    }
+    
+    /* move (and maybe capture) */
     msrc(board, move) = 0;
-    // TODO: care for en passant capture
     mdst(board, move) = move->piece;
     
     /* castling */
-    if ((move->piece & PIECE_MASK) == KING &&
+    if (piece == KING &&
         move->fromfile == fileidx('e')) {
-        uint8_t color = move->piece & COLOR_MASK;
         
         if (move->tofile == fileidx('g')) {
             board[move->torow][fileidx('h')] = 0;
@@ -245,17 +266,23 @@
         
     } else if (len == 4) {
         move->piece = getpiece(mstr[0]);
+        if (!move->piece) {
+            move->piece = PAWN;
+            move->fromfile = fileidx(mstr[0]);
+        }
         if (mstr[1] == 'x') {
             /* capture (e.g. "Nxf3", "dxe5") */
             move->capture = TRUE;
-            if (!move->piece) {
-                move->piece = PAWN;
-                move->fromfile = fileidx(mstr[0]);
+        } else {
+            /* move (e.g. "Ndf3", "N2c3", "e2e4") */
+            if (isfile(mstr[1])) {
+                move->fromfile = fileidx(mstr[1]);
+                if (move->piece == PAWN) {
+                    move->piece = 0;
+                }
+            } else {
+                move->fromrow = rowidx(mstr[1]);
             }
-        } else {
-            /* move (e.g. "Ndf3", "N2c3") */
-            move->fromfile = isfile(mstr[1]) ?
-                fileidx(mstr[1]) : rowidx(mstr[1]);
         }
         move->tofile = fileidx(mstr[2]);
         move->torow = rowidx(mstr[3]);
diff -r 970748b9a73b -r 7ffd66591afe src/rules/pawn.c
--- a/src/rules/pawn.c	Wed Mar 26 14:53:15 2014 +0100
+++ b/src/rules/pawn.c	Fri Mar 28 11:45:01 2014 +0100
@@ -35,8 +35,9 @@
         if (move->fromrow == move->torow + d && (
             move->fromfile == move->tofile + 1 ||
             move->fromfile == move->tofile - 1)) {
-            // TODO: en passant
-            return mdst(board,move) != 0; /* color has been checked */
+
+            return mdst(board,move)
+                || (board[move->fromrow][move->tofile] & ENPASSANT_THREAT);
         } else {
             return FALSE;
         }