Implement hover command

[xboard.git] / backend.c

diff --git a/backend.c b/backend.c
index 15c3e42..24ae75d 100644 (file)
--- a/backend.c
+++ b/backend.c
@@ -269,6 +269,7 @@ char chatPartner[MAX_CHAT][MSG_SIZ]; /* [HGM] chat: list of chatting partners */
 extern int chatCount;
 int chattingPartner;
 char marker[BOARD_RANKS][BOARD_FILES]; /* [HGM] marks for target squares */
+char legal[BOARD_RANKS][BOARD_FILES];  /* [HGM] legal target squares */
 char lastMsg[MSG_SIZ];
 ChessSquare pieceSweep = EmptySquare;
 ChessSquare promoSweep = EmptySquare, defaultPromoChoice;
@@ -7019,13 +7020,22 @@ MarkByFEN(char *fen)
 {
        int r, f;
        if(!appData.markers || !appData.highlightDragging) return;
-       for(r=0; r<BOARD_HEIGHT; r++) for(f=BOARD_LEFT; f<BOARD_RGHT; f++) marker[r][f] = 0;
+       for(r=0; r<BOARD_HEIGHT; r++) for(f=BOARD_LEFT; f<BOARD_RGHT; f++) legal[r][f] = 0;
        r=BOARD_HEIGHT-1; f=BOARD_LEFT;
        while(*fen) {
            int s = 0;
            marker[r][f] = 0;
+           if(*fen >= 'A' && *fen <= 'Z') legal[r][f] = 1; else
+           if(*fen >= 'a' && *fen <= 'z') *fen += 'A' - 'a';
            if(*fen == '/' && f > BOARD_LEFT) f = BOARD_LEFT, r--; else
+           if(*fen == 'T') marker[r][f++] = 0; else
            if(*fen == 'Y') marker[r][f++] = 1; else
+           if(*fen == 'G') marker[r][f++] = 3; else
+           if(*fen == 'B') marker[r][f++] = 4; else
+           if(*fen == 'C') marker[r][f++] = 5; else
+           if(*fen == 'M') marker[r][f++] = 6; else
+           if(*fen == 'W') marker[r][f++] = 7; else
+           if(*fen == 'D') marker[r][f++] = 8; else
            if(*fen == 'R') marker[r][f++] = 2; else {
                while(*fen <= '9' && *fen >= '0') s = 10*s + *fen++ - '0';
              f += s; fen -= s>0;
@@ -7101,9 +7111,34 @@ CanPromote (ChessSquare piece, int y)
                piece == WhiteLance && y == BOARD_HEIGHT-2 );
 }
 
+void
+HoverEvent (int hiX, int hiY, int x, int y)
+{
+       static char baseMarker[BOARD_RANKS][BOARD_FILES], baseLegal[BOARD_RANKS][BOARD_FILES];
+       int r, f;
+       if(!first.highlight) return;
+       if(hiX == -1 && hiY == -1 && x == fromX && y == fromY) // record markings 
+         for(r=0; r<BOARD_HEIGHT; r++) for(f=BOARD_LEFT; f<BOARD_RGHT; f++)
+           baseMarker[r][f] = marker[r][f], baseLegal[r][f] = legal[r][f];
+       else if(hiX != x || hiY != y) {
+         // [HGM] lift: entered new to-square; redraw arrow, and inform engine
+         for(r=0; r<BOARD_HEIGHT; r++) for(f=BOARD_LEFT; f<BOARD_RGHT; f++)
+           marker[r][f] = baseMarker[r][f], legal[r][f] = baseLegal[r][f];
+         if(marker[y][x] == 2 && legal[y][x] == 1) {
+           char buf[MSG_SIZ];
+           snprintf(buf, MSG_SIZ, "hover %c%d\n", x + AAA, y + ONE - '0');
+           SendToProgram(buf, &first);
+         }
+         SetHighlights(fromX, fromY, x, y);
+       }
+}
+
 void ReportClick(char *action, int x, int y)
 {
        char buf[MSG_SIZ]; // Inform engine of what user does
+       int r, f;
+       if(action[0] == 'l') // mark any target square of a lifted piece as legal to-square, clear markers
+         for(r=0; r<BOARD_HEIGHT; r++) for(f=BOARD_LEFT; f<BOARD_RGHT; f++) legal[r][f] = 1, marker[r][f] = 0;
        if(!first.highlight || gameMode == EditPosition) return;
        snprintf(buf, MSG_SIZ, "%s %c%d%s\n", action, x+AAA, y+ONE-'0', controlKey && action[0]=='p' ? "," : "");
        SendToProgram(buf, &first);
@@ -7321,6 +7356,13 @@ LeftClick (ClickType clickType, int xPix, int yPix)
 
     clearFlag = 0;
 
+    if(gameMode != EditPosition && !appData.testLegality && !legal[y][x]) {
+       if(dragging) DragPieceEnd(xPix, yPix), dragging = 0;
+       DisplayMessage(_("only marked squares are legal"),"");
+       DrawPosition(TRUE, NULL);
+       return; // ignore to-click
+    }
+
     /* we now have a different from- and (possibly off-board) to-square */
     /* Completed move */
     if(!sweepSelecting) {