From f7e7dc832cce623d716a05b2be6c63c8cae541d7 Mon Sep 17 00:00:00 2001
From: H.G. Muller <h.g.muller@hccnet.nl>
Date: Sun, 7 Feb 2010 11:53:03 +0100
Subject: [PATCH] Let second click on piece make only capture, with -oneClickMove

Normally this would clear the highlighting of that piece.
Required new field in DisambiguateClosure to count nr of captures.
---
 backend.c |    8 ++++++--
 moves.c   |    3 ++-
 moves.h   |    1 +
 3 files changed, 9 insertions(+), 3 deletions(-)

diff --git a/backend.c b/backend.c
index 387f87c..42f434e 100644
--- a/backend.c
+++ b/backend.c
@@ -5552,7 +5552,7 @@ OKToStartUserMove(x, y)
 }
 
 Boolean
-OnlyMove(int *x, int *y) {
+OnlyMove(int *x, int *y, Boolean captures) {
     DisambiguateClosure cl;
     if (appData.zippyPlay) return FALSE;
     switch(gameMode) {
@@ -5576,6 +5576,7 @@ OnlyMove(int *x, int *y) {
     cl.promoCharIn = NULLCHAR;
     Disambiguate(boards[currentMove], PosFlags(currentMove), &cl);
     if( cl.kind == NormalMove ||
+	cl.kind == AmbiguousMove && captures && cl.captures == 1 ||
 	cl.kind == WhitePromotionQueen || cl.kind == BlackPromotionQueen ||
 	cl.kind == WhitePromotionKnight || cl.kind == BlackPromotionKnight ||
 	cl.kind == WhiteCapturesEnPassant || cl.kind == BlackCapturesEnPassant) {
@@ -5594,6 +5595,7 @@ OnlyMove(int *x, int *y) {
     cl.promoCharIn = NULLCHAR;
     Disambiguate(boards[currentMove], PosFlags(currentMove), &cl);
     if( cl.kind == NormalMove ||
+	cl.kind == AmbiguousMove && captures && cl.captures == 1 ||
 	cl.kind == WhitePromotionQueen || cl.kind == BlackPromotionQueen ||
 	cl.kind == WhitePromotionKnight || cl.kind == BlackPromotionKnight ||
 	cl.kind == WhiteCapturesEnPassant || cl.kind == BlackCapturesEnPassant) {
@@ -6099,7 +6101,7 @@ void LeftClick(ClickType clickType, int xPix, int yPix)
     autoQueen = appData.alwaysPromoteToQueen;
 
     if (fromX == -1) {
-      if(!appData.oneClick || !OnlyMove(&x, &y)) {
+      if(!appData.oneClick || !OnlyMove(&x, &y, FALSE)) {
 	if (clickType == Press) {
 	    /* First square */
 	    if (OKToStartUserMove(x, y)) {
@@ -6140,6 +6142,7 @@ void LeftClick(ClickType clickType, int xPix, int yPix)
 	     !(fromP == BlackKing && toP == BlackRook && frc))) {
 	    /* Clicked again on same color piece -- changed his mind */
 	    second = (x == fromX && y == fromY);
+	   if(!second || !OnlyMove(&x, &y, TRUE)) {
 	    if (appData.highlightDragging) {
 		SetHighlights(x, y, -1, -1);
 	    } else {
@@ -6152,6 +6155,7 @@ void LeftClick(ClickType clickType, int xPix, int yPix)
 		DragPieceBegin(xPix, yPix);
 	    }
 	    return;
+	   }
 	}
 	// ignore clicks on holdings
 	if(x < BOARD_LEFT || x >= BOARD_RGHT) return;
diff --git a/moves.c b/moves.c
index 8380f1b..463935d 100644
--- a/moves.c
+++ b/moves.c
@@ -1229,6 +1229,7 @@ void DisambiguateCallback(board, flags, kind, rf, ff, rt, ft, closure)
 	cl->rt = wildCard ? cl->rtIn : rt;
 	cl->ft = wildCard ? cl->ftIn : ft;
 	cl->kind = kind;
+	cl->captures += (board[cl->rt][cl->ft] != EmptySquare); // [HGM] oneclick: count captures
     }
 }
 
@@ -1239,7 +1240,7 @@ void Disambiguate(board, flags, closure)
 {
     int illegal = 0; char c = closure->promoCharIn;
 
-    closure->count = 0;
+    closure->count = closure->captures = 0;
     closure->rf = closure->ff = closure->rt = closure->ft = 0;
     closure->kind = ImpossibleMove;
     if (appData.debugMode) {
diff --git a/moves.h b/moves.h
index b783727..82c7482 100644
--- a/moves.h
+++ b/moves.h
@@ -157,6 +157,7 @@ typedef struct {
     int rf, ff, rt, ft;
     int promoChar; /* 'q' if a promotion and promoCharIn was NULLCHAR */
     int count;     /* Number of possibilities found */
+    int captures;  /* [HGM] oneclick: number of matching captures */
 } DisambiguateClosure;
 
 /* Disambiguate a partially-known move */
-- 
1.7.0.4