Added an automatic `Solve' feature to most games. This is useful for

various things:
 - if you haven't fully understood what a game is about, it gives
   you an immediate example of a puzzle plus its solution so you can
   understand it
 - in some games it's useful to compare your solution with the real
   one and see where you made a mistake
 - in the rearrangement games (Fifteen, Sixteen, Twiddle) it's handy
   to be able to get your hands on a pristine grid quickly so you
   can practise or experiment with manoeuvres on it
 - it provides a good way of debugging the games if you think you've
   encountered an unsolvable grid!

[originally from svn r5731]

1 files changed, 18 insertions, 5 deletions

diff --git a/windows.c b/windows.c
index c570b29..4df9175 100644
--- a/windows.c
+++ b/windows.c
@@ -28,11 +28,12 @@
 #define IDM_UNDO      0x0030
 #define IDM_REDO      0x0040
 #define IDM_COPY      0x0050
-#define IDM_QUIT      0x0060
-#define IDM_CONFIG    0x0070
-#define IDM_SEED      0x0080
-#define IDM_HELPC     0x0090
-#define IDM_GAMEHELP  0x00A0
+#define IDM_SOLVE     0x0060
+#define IDM_QUIT      0x0070
+#define IDM_CONFIG    0x0080
+#define IDM_SEED      0x0090
+#define IDM_HELPC     0x00A0
+#define IDM_GAMEHELP  0x00B0
 #define IDM_PRESETS   0x0100
 
 #define HELP_FILE_NAME  "puzzles.hlp"
@@ -487,6 +488,10 @@ static frontend *new_window(HINSTANCE inst, char *game_id, char **error)
 	    AppendMenu(menu, MF_SEPARATOR, 0, 0);
 	    AppendMenu(menu, MF_ENABLED, IDM_COPY, "Copy");
 	}
+	if (thegame.can_solve) {
+	    AppendMenu(menu, MF_SEPARATOR, 0, 0);
+	    AppendMenu(menu, MF_ENABLED, IDM_SOLVE, "Solve");
+	}
 	AppendMenu(menu, MF_SEPARATOR, 0, 0);
 	AppendMenu(menu, MF_ENABLED, IDM_QUIT, "Exit");
         if (fe->help_path) {
@@ -930,6 +935,14 @@ static LRESULT CALLBACK WndProc(HWND hwnd, UINT message,
 		    MessageBeep(MB_ICONWARNING);
 	    }
 	    break;
+	  case IDM_SOLVE:
+	    {
+		char *msg = midend_solve(fe->me);
+		if (msg)
+		    MessageBox(hwnd, msg, "Unable to solve",
+			       MB_ICONERROR | MB_OK);
+	    }
+	    break;
 	  case IDM_QUIT:
 	    if (!midend_process_key(fe->me, 0, 0, 'q'))
 		PostQuitMessage(0);