Allow Lion double-moves in opening book

Double moves can now be encoded in a Polyglot es promoType = 2, and
a code for two King steps in the to-square. The moves are retrieved
in the Alien Edition protocol format (i.e. comma-separated LAN).
HandleMachineMove had to be adapted to handle the two legs coming as one,
but otherwise the book code can just send the retrieved line directly
to the engine.
 For Edit Book the format has to be converted to TSA-like for display,
to make the move parser that will read it on saving understand the move
as a single one.

diff --git a/backend.c b/backend.c
index f74b597..125fd3d 100644 (file)
--- a/backend.c
+++ b/backend.c
@@ -7056,6 +7056,7 @@ UserMoveEvent(int fromX, int fromY, int toX, int toY, int promoChar)
     if(addToBookFlag) { // adding moves to book
        char buf[MSG_SIZ], move[MSG_SIZ];
         CoordsToAlgebraic(boards[currentMove], PosFlags(currentMove), fromY, fromX, toY, toX, promoChar, move);
+       if(killX >= 0) snprintf(move, MSG_SIZ, "%c%dx%c%d-%c%d", fromX + AAA, fromY + ONE - '0', killX + AAA, killY + ONE - '0', toX + AAA, toY + ONE - '0');
        snprintf(buf, MSG_SIZ, "  0.0%%     1  %s\n", move);
        AddBookMove(buf);
        addToBookFlag = FALSE;
@@ -8695,7 +8696,12 @@ FakeBookMove: // [HGM] book: we jump here to simulate machine moves after book h
        if(machineMove[strlen(machineMove)-1] == ',') { // move ends in coma: non-final leg of composite move
            safeStrCpy(firstLeg, machineMove, 20); // just remember it for processing when second leg arrives
            return;
-       } else if(firstLeg[0]) { // there was a previous leg;
+       }
+       if(p = strchr(machineMove, ',')) {         // we got both legs in one (happens on book move)
+           safeStrCpy(firstLeg, machineMove, 20); // kludge: fake we received the first leg earlier, and clip it off
+           safeStrCpy(machineMove, firstLeg + (p - machineMove) + 1, 20);
+       }
+       if(firstLeg[0]) { // there was a previous leg;
            // only support case where same piece makes two step
            char buf[20], *p = machineMove+1, *q = buf+1, f;
            safeStrCpy(buf, machineMove, 20);

diff --git a/book.c b/book.c
index c956362..090ae1b 100644 (file)
--- a/book.c
+++ b/book.c
@@ -484,8 +484,11 @@ find_key (FILE *f, uint64 key, entry_t *entry)
     }
 }
 
+static int xStep[] = { 0, 1, 1, 1, 0,-1,-1,-1 };
+static int yStep[] = { 1, 1, 0,-1,-1,-1, 0, 1 };
+
 void
-move_to_string (char move_s[10], uint16 move)
+move_to_string (char move_s[20], uint16 move)
 {
     int f,fr,ff,t,tr,tf,p;
     int width = BOARD_RGHT - BOARD_LEFT, size; // allow for alternative board formats
@@ -512,7 +515,12 @@ move_to_string (char move_s[10], uint16 move)
        move_s[1] = '@';     // drop symbol
        p = 0;
     } else if(p == 10) { // decode Lion move
-       
+       int i = t & 7, j = t >> 3 & 7;
+       tf = ff + xStep[i] + xStep[j]; tr = fr + yStep[i] + yStep[j]; // calculate true to-square
+       snprintf(move_s, 20, "%c%d%c%d,%c%d%c%d", ff + 'a', fr + 1 - (BOARD_HEIGHT == 10),
+                                                 ff + xStep[i] + 'a', fr + yStep[i] + 1 - (BOARD_HEIGHT == 10),
+                                                 ff + xStep[i] + 'a', fr + yStep[i] + 1 - (BOARD_HEIGHT == 10),
+                                                 tf + 'a', tr + 1 - (BOARD_HEIGHT == 10) );
        p = 0;
     }
 
@@ -730,8 +738,10 @@ MovesToText(int count, entry_t *entries)
        for(i=0; i<count; i++) totalWeight += entries[i].weight;
        *p = 0;
        for(i=0; i<count; i++) {
-           char buf[MSG_SIZ];
+           char buf[MSG_SIZ], c1, c2, c3; int i1, i2, i3;
            move_to_string(algMove, entries[i].move);
+           if(sscanf(algMove, "%c%d%*c%*d,%c%d%c%d", &c1, &i1, &c2, &i2, &c3, &i3) == 6)
+               snprintf(algMove, 12, "%c%dx%c%d-%c%d", c1, i1, c2, i2, c3, i3); // cast double-moves in format SAN parser will understand
            buf[0] = NULLCHAR;
            if(entries[i].learnCount || entries[i].learnPoints)
                snprintf(buf, MSG_SIZ, " {%d/%d}", entries[i].learnPoints, entries[i].learnCount);
@@ -752,6 +762,18 @@ CoordsToMove (int fromX, int fromY, int toX, int toY, char promoChar)
     if(!promote_pieces[i]) i = 0;
     else if(i == 9 && gameInfo.variant == VariantChu) i = 1; // on 12x12 only 3 promotion codes available, so use 1 to indicate promotion
     if(fromY == DROP_RANK) i = 9, from = ToUpper(PieceToChar(fromX)) - '@';
+    if(killX >= 0) { // multi-leg move
+       int dx = killX - fromX, dy = killY - fromY;
+       for(i=0; i<8; i++) if(dx == xStep[i] && dy == yStep[i]) {
+           int j;
+           dx = toX - killX; dy = toY - killY;
+           for(j=0; j<8; j++) if(dx == xStep[j] && dy == yStep[j]) {
+               // special encoding in to-square, with promoType = 2. Assumes board >= 64 squares!
+               return i + 8*j + (2 * width * BOARD_HEIGHT + from) * width * BOARD_HEIGHT;
+           }
+       }
+       i = 0; // if not a valid Lion move, ignore kill-square and promoChar
+    }
     return to + (i * width * BOARD_HEIGHT + from) * width * BOARD_HEIGHT;
 }
 
@@ -772,6 +794,7 @@ TextToMoves (char *text, int moveNum, entry_t *entries)
            valid = ParseOneMove(text, moveNum, &moveType, &fromX, &fromY, &toX, &toY, &promoChar);
            text = strstr(text, yy_textstr) + strlen(yy_textstr); // skip what we parsed
            if(!valid || moveType != NormalMove && moveType != WhiteDrop && moveType != BlackDrop
+                                               && moveType != FirstLeg
                                                 && moveType != WhitePromotion && moveType != BlackPromotion
                                                 && moveType != WhiteCapturesEnPassant && moveType != BlackCapturesEnPassant
                                                 && moveType != WhiteKingSideCastle && moveType != BlackKingSideCastle
@@ -783,7 +806,7 @@ TextToMoves (char *text, int moveNum, entry_t *entries)
                entries[count].learnPoints = 0;
                entries[count].learnCount  = 0;
            }
-           entries[count].move = CoordsToMove(fromX, fromY, toX, toY, promoChar);
+           entries[count].move = CoordsToMove(fromX, fromY, toX, toY, promoChar); killX = killY = -1;
            entries[count].key  = hashKey;
            entries[count].weight = w;
            count++;