3 files changed, 350 insertions, 317 deletions

diff --git a/apps/plugins/chessbox/chessbox.c b/apps/plugins/chessbox/chessbox.c
index 161de45e90..2e863b957b 100644
--- a/apps/plugins/chessbox/chessbox.c
+++ b/apps/plugins/chessbox/chessbox.c
@@ -26,9 +26,9 @@
 
 /* type definitions */
 struct cb_command {
-        int type;
-        char mv_s[5];
-        unsigned short mv;
+    int type;
+    char mv_s[5];
+    unsigned short mv;
 };
 
 /* External bitmaps */
@@ -131,7 +131,7 @@ PLUGIN_HEADER
 #define TILE_WIDTH  8
 #define TILE_HEIGHT 8
 #else
-  #error BEJEWELED: Unsupported LCD
+    #error CHESSBOX: Unsupported LCD
 #endif
 
 /* Calculate Offsets */
@@ -139,11 +139,15 @@ PLUGIN_HEADER
 #define YOFS ((LCD_HEIGHT-8*TILE_HEIGHT)/2)
 
 /* commands enum */
-#define COMMAND_MOVE    1
-#define COMMAND_PLAY    2
-#define COMMAND_LEVEL   3
-/*#define COMMAND_RESTART       4*/
-#define COMMAND_QUIT    5
+#define COMMAND_NOP        0
+#define COMMAND_MOVE       1
+#define COMMAND_PLAY       2
+#define COMMAND_LEVEL      3
+/*#define COMMAND_RESTART    4*/
+#define COMMAND_QUIT       5
+
+/* "While thinking" command */
+int wt_command = COMMAND_NOP;
 
 /* GCC wants this to be present for some targets */
 void* memcpy(void* dst, const void* src, size_t size)
@@ -153,278 +157,298 @@ void* memcpy(void* dst, const void* src, size_t size)
 
 /* ---- Get the board column and row (e2 f.e.) for a physical x y ---- */
 void xy2cr ( short x, short y, short *c, short *r ) {
-        if (computer == black ) {
-                *c = x ;
-                *r = y ;
-        } else {
-                *c = 7 - x ;
-                *r = 7 - y ;
-        }
+    if (computer == black ) {
+        *c = x ;
+        *r = y ;
+    } else {
+        *c = 7 - x ;
+        *r = 7 - y ;
+    }
 }
 
 /* ---- get physical x y for a board column and row (e2 f.e.) ---- */
 void cr2xy ( short c, short r, short *x, short *y ) {
-        if ( computer == black ) {
-                *x = c ;
-                *y = r ;
-        } else {
-                *x = 7 - c ;
-                *y = 7 - r ;
-        }
+    if ( computer == black ) {
+        *x = c ;
+        *y = r ;
+    } else {
+        *x = 7 - c ;
+        *y = 7 - r ;
+    }
 }
 
 /* ---- Draw a complete board ---- */
 static void cb_drawboard (void) {
     short r , c , x , y ;
-        short l , piece , p_color ;
-        int b_color=1;
-        
-        rb->lcd_clear_display();
+    short l , piece , p_color ;
+    int b_color=1;
+    
+    rb->lcd_clear_display();
 
-        for (r = 0; r < 8; r++) {
+    for (r = 0; r < 8; r++) {
         for (c = 0; c < 8; c++) {
             l = locn[r][c];
             piece   = board[l] ;
-                        p_color = color[l] ;
-                        cr2xy ( c , r , &x , &y );
-                        if ( piece == no_piece ) {
-                                rb->lcd_bitmap_part ( chessbox_pieces , 0 ,
-                                                                          TILE_HEIGHT * b_color ,
-                                                                          TILE_WIDTH ,
-                                                                          XOFS + x*TILE_WIDTH ,
-                                                      YOFS + ( 7 - y )*TILE_HEIGHT ,
-                                                      TILE_WIDTH ,
-                                                      TILE_HEIGHT );
-                        } else {
-                            rb->lcd_bitmap_part ( chessbox_pieces ,
-                                                                          0 ,
-                                                          2 * TILE_HEIGHT +
-                                                          4 * TILE_HEIGHT * ( piece - 1 ) +
-                                                          2 * TILE_HEIGHT * p_color +
-                                                          TILE_HEIGHT * b_color ,
-                                                                          TILE_WIDTH ,
-                                                                          XOFS + x*TILE_WIDTH ,
-                                                      YOFS + (7 - y)*TILE_HEIGHT ,
-                                                      TILE_WIDTH ,
-                                                      TILE_HEIGHT );
-                        }
-                        b_color = (b_color == 1) ? 0 : 1 ;
+            p_color = color[l] ;
+            cr2xy ( c , r , &x , &y );
+            if ( piece == no_piece ) {
+                rb->lcd_bitmap_part ( chessbox_pieces , 0 ,
+                                      TILE_HEIGHT * b_color ,
+                                      TILE_WIDTH ,
+                                      XOFS + x*TILE_WIDTH ,
+                                      YOFS + ( 7 - y )*TILE_HEIGHT ,
+                                      TILE_WIDTH ,
+                                      TILE_HEIGHT );
+            } else {
+                rb->lcd_bitmap_part ( chessbox_pieces ,
+                                      0 ,
+                                      2 * TILE_HEIGHT +
+                                          4 * TILE_HEIGHT * ( piece - 1 ) +
+                                          2 * TILE_HEIGHT * p_color +
+                                          TILE_HEIGHT * b_color ,
+                                      TILE_WIDTH ,
+                                      XOFS + x*TILE_WIDTH ,
+                                      YOFS + (7 - y)*TILE_HEIGHT ,
+                                      TILE_WIDTH ,
+                                      TILE_HEIGHT );
+            }
+            b_color = (b_color == 1) ? 0 : 1 ;
         }
-                b_color = (b_color == 1) ? 0 : 1 ;
+        b_color = (b_color == 1) ? 0 : 1 ;
+    }
+    
+    /* draw board limits */
+    if ( LCD_WIDTH > TILE_WIDTH*8 ) {
+        rb->lcd_set_drawmode ( DRMODE_FG );
+        rb->lcd_drawline ( XOFS - 1 , YOFS ,
+                           XOFS - 1 , YOFS + TILE_HEIGHT*8 );
+        rb->lcd_drawline ( XOFS + 8*TILE_WIDTH , YOFS ,
+                           XOFS + 8*TILE_WIDTH , YOFS + TILE_HEIGHT*8 );
+    }
+    if ( LCD_HEIGHT > TILE_HEIGHT*8 ) {
+        rb->lcd_set_drawmode ( DRMODE_FG );
+        rb->lcd_drawline ( XOFS , YOFS - 1 ,
+                           XOFS + TILE_WIDTH*8 , YOFS - 1 );
+        rb->lcd_drawline ( XOFS , YOFS + TILE_HEIGHT*8  ,
+                           XOFS + 8*TILE_WIDTH , YOFS + TILE_HEIGHT*8 );
     }
-        
-        /* draw board limits */
-        if ( LCD_WIDTH > TILE_WIDTH*8 ) {
-                rb->lcd_set_drawmode ( DRMODE_FG );
-                rb->lcd_drawline ( XOFS - 1 , YOFS ,
-                                   XOFS - 1 , YOFS + TILE_HEIGHT*8 );
-                rb->lcd_drawline ( XOFS + 8*TILE_WIDTH , YOFS ,
-                                   XOFS + 8*TILE_WIDTH , YOFS + TILE_HEIGHT*8 );
-        }
-        if ( LCD_HEIGHT > TILE_HEIGHT*8 ) {
-                rb->lcd_set_drawmode ( DRMODE_FG );
-                rb->lcd_drawline ( XOFS , YOFS - 1 ,
-                                   XOFS + TILE_WIDTH*8 , YOFS - 1 );
-                rb->lcd_drawline ( XOFS , YOFS + TILE_HEIGHT*8  ,
-                                   XOFS + 8*TILE_WIDTH , YOFS + TILE_HEIGHT*8 );
-        }
-        rb->lcd_update();
+    rb->lcd_update();
 }
 
 /* ---- Switch mark on board ---- */
 void cb_switch ( short x , short y ) {
-        rb->lcd_set_drawmode ( DRMODE_COMPLEMENT );
-        rb->lcd_drawrect ( XOFS + x*TILE_WIDTH + 1 ,
-                           YOFS + ( 7 - y )*TILE_HEIGHT +1 ,
-                           TILE_WIDTH-2 , TILE_HEIGHT-2 );
-        rb->lcd_update();
+    rb->lcd_set_drawmode ( DRMODE_COMPLEMENT );
+    rb->lcd_drawrect ( XOFS + x*TILE_WIDTH + 1 ,
+                       YOFS + ( 7 - y )*TILE_HEIGHT +1 ,
+                       TILE_WIDTH-2 , TILE_HEIGHT-2 );
+    rb->lcd_update();
+}
+
+/* ---- callback for capturing interaction while thinking ---- */
+void cb_wt_callback ( void ) {
+    int button = BUTTON_NONE;
+    
+    wt_command = COMMAND_NOP;
+    button = rb->button_get(false);
+    switch (button) {
+        case CB_QUIT:
+            wt_command = COMMAND_QUIT;
+            timeout = true;
+            break;
+        case CB_PLAY:
+            wt_command = COMMAND_PLAY;
+            timeout = true;
+            break;
+    }
 }
 
 /* ---- increase playing level ---- */
 void cb_levelup ( void ) {
-        Level ++;
-        if ( Level == 8 ) Level = 1;
-        switch (Level) {
-        case 1 :
-                        TCmoves = 60;
-                        TCminutes = 5;
-                        rb->splash ( 50 , true , "Level 1: 60 moves / 5 min" );
-                        break;
-        case 2 :
-                        TCmoves = 60;
-                        TCminutes = 15;
-                        rb->splash ( 50 , true , "Level 2: 60 moves / 15 min" );
-                        break;
-        case 3 :
-                        TCmoves = 60;
-                        TCminutes = 30;
-                        rb->splash ( 50 , true , "Level 3: 60 moves / 30 min" );
-                        break;
-        case 4 :
-                        TCmoves = 40;
-                        TCminutes = 30;
-                        rb->splash ( 50 , true , "Level 4: 40 moves / 30 min" );
-                        break;
-        case 5 :
-                        TCmoves = 40;
-                        TCminutes = 60;
-                        rb->splash ( 50 , true , "Level 5: 40 moves / 60 min" );
-                        break;
-        case 6 :
-                        TCmoves = 40;
-                        TCminutes = 120;
-                        rb->splash ( 50 , true , "Level 6: 40 moves / 120 min" );
-                        break;
-        case 7 :
-                        TCmoves = 40;
-                        TCminutes = 240;
-                        rb->splash ( 50 , true , "Level 7: 40 moves / 240 min" );
-                        break;
-        case 8 :
-                        TCmoves = 1;
-                        TCminutes = 15;
-                        rb->splash ( 50 , true , "Level 8: 1 move / 15 min" );
-                        break;
-        case 9 :
-                        TCmoves = 1;
-                        TCminutes = 60;
-                        rb->splash ( 50 , true , "Level 9: 1 move / 60 min" );
-                        break;
-        case 10 :
-                        TCmoves = 1;
-                        TCminutes = 600;
-                        rb->splash ( 50 , true , "Level 10: 1 move / 600 min" );
-                        break;
-        }
+    Level ++;
+    if ( Level == 8 ) Level = 1;
+    switch (Level) {
+        case 1 :
+            TCmoves = 60;
+            TCminutes = 5;
+            rb->splash ( 50 , true , "Level 1: 60 moves / 5 min" );
+            break;
+        case 2 :
+            TCmoves = 60;
+            TCminutes = 15;
+            rb->splash ( 50 , true , "Level 2: 60 moves / 15 min" );
+            break;
+        case 3 :
+            TCmoves = 60;
+            TCminutes = 30;
+            rb->splash ( 50 , true , "Level 3: 60 moves / 30 min" );
+            break;
+        case 4 :
+            TCmoves = 40;
+            TCminutes = 30;
+            rb->splash ( 50 , true , "Level 4: 40 moves / 30 min" );
+            break;
+        case 5 :
+            TCmoves = 40;
+            TCminutes = 60;
+            rb->splash ( 50 , true , "Level 5: 40 moves / 60 min" );
+            break;
+        case 6 :
+            TCmoves = 40;
+            TCminutes = 120;
+            rb->splash ( 50 , true , "Level 6: 40 moves / 120 min" );
+            break;
+        case 7 :
+            TCmoves = 40;
+            TCminutes = 240;
+            rb->splash ( 50 , true , "Level 7: 40 moves / 240 min" );
+            break;
+        case 8 :
+            TCmoves = 1;
+            TCminutes = 15;
+            rb->splash ( 50 , true , "Level 8: 1 move / 15 min" );
+            break;
+          case 9 :
+            TCmoves = 1;
+            TCminutes = 60;
+            rb->splash ( 50 , true , "Level 9: 1 move / 60 min" );
+            break;
+          case 10 :
+            TCmoves = 1;
+            TCminutes = 600;
+            rb->splash ( 50 , true , "Level 10: 1 move / 600 min" );
+            break;
+    }
     TCflag = (TCmoves > 1);
-        SetTimeControl();
+      SetTimeControl();
 };
 
 /* ---- main user loop ---- */
 struct cb_command cb_getcommand (void) {
-        static short x = 4 , y = 4 ;
-        short c , r , l;
-        int button, lastbutton = BUTTON_NONE;
-        int marked = false , from_marked = false ;
-        short marked_x = 0 , marked_y = 0 ;
-        struct cb_command result = { 0, {0,0,0,0,0}, 0 };
-        
-        cb_switch ( x , y );
-        /* main loop */
-        while ( true ) {
-                button = rb->button_get(true);
-                switch (button) {
-                        case CB_QUIT:
-                                result.type = COMMAND_QUIT;
-                                return result;
-/*                      case CB_RESTART:
-                                result.type = COMMAND_RESTART;
-                                return result;*/
-                        case CB_LEVEL:
-                                result.type = COMMAND_LEVEL;
-                                return result;
-                        case CB_PLAY:
+    static short x = 4 , y = 4 ;
+    short c , r , l;
+    int button, lastbutton = BUTTON_NONE;
+    int marked = false , from_marked = false ;
+    short marked_x = 0 , marked_y = 0 ;
+    struct cb_command result = { 0, {0,0,0,0,0}, 0 };
+    
+    cb_switch ( x , y );
+    /* main loop */
+    while ( true ) {
+        button = rb->button_get(true);
+        switch (button) {
+            case CB_QUIT:
+                result.type = COMMAND_QUIT;
+                return result;
+#if 0
+            case CB_RESTART:
+                result.type = COMMAND_RESTART;
+                return result;
+#endif
+            case CB_LEVEL:
+                result.type = COMMAND_LEVEL;
+                return result;
+            case CB_PLAY:
 #ifdef CB_PLAY_PRE
                 if (lastbutton != CB_PLAY_PRE)
                     break;
 #endif
-                                result.type = COMMAND_PLAY;
-                                return result;
-                        case CB_UP:
-                                if ( !from_marked ) cb_switch ( x , y );
-                                y++;
-                                if ( y == 8 ) {
-                                        y = 0;
-                                        x--;
-                                        if ( x < 0 ) x = 7;
-                                }
-                                if ( marked && ( marked_x == x ) && ( marked_y == y ) ) {
-                                        from_marked = true ;
-                                } else {
-                                        from_marked = false ;
-                                        cb_switch ( x , y );
-                                }
-                                break;
-                        case CB_DOWN:
-                                if ( !from_marked ) cb_switch ( x , y );
-                                y--;
-                                if ( y < 0 ) {
-                                        y = 7;
-                                        x++;
-                                        if ( x == 8 ) x = 0;
-                                }
-                                if ( marked && ( marked_x == x ) && ( marked_y == y ) ) {
-                                        from_marked = true ;
-                                } else {
-                                        from_marked = false ;
-                                        cb_switch ( x , y );
-                                }
-                                break;
-                        case CB_LEFT:
-                                if ( !from_marked ) cb_switch ( x , y );
-                                x--;
-                                if ( x < 0 ) {
-                                        x = 7;
-                                        y++;
-                                        if ( y == 8 ) y = 0;
-                                }
-                                if ( marked && ( marked_x == x ) && ( marked_y == y ) ) {
-                                        from_marked = true ;
-                                } else {
-                                        from_marked = false ;
-                                        cb_switch ( x , y );
-                                }
-                                break;
-                        case CB_RIGHT:
-                                if ( !from_marked ) cb_switch ( x , y );
-                                x++;
-                                if ( x == 8 ) {
-                                        x = 0;
-                                        y--;
-                                        if ( y < 0 ) y = 7;
-                                }
-                                if ( marked && ( marked_x == x ) && ( marked_y == y ) ) {
-                                        from_marked = true ;
-                                } else {
-                                        from_marked = false ;
-                                        cb_switch ( x , y );
-                                }
-                                break;
-                        case CB_SELECT:
+                result.type = COMMAND_PLAY;
+                return result;
+            case CB_UP:
+                if ( !from_marked ) cb_switch ( x , y );
+                y++;
+                if ( y == 8 ) {
+                    y = 0;
+                    x--;
+                    if ( x < 0 ) x = 7;
+                }
+                if ( marked && ( marked_x == x ) && ( marked_y == y ) ) {
+                    from_marked = true ;
+                } else {
+                    from_marked = false ;
+                    cb_switch ( x , y );
+                }
+                break;
+            case CB_DOWN:
+                if ( !from_marked ) cb_switch ( x , y );
+                y--;
+                if ( y < 0 ) {
+                    y = 7;
+                    x++;
+                    if ( x == 8 ) x = 0;
+                }
+                if ( marked && ( marked_x == x ) && ( marked_y == y ) ) {
+                    from_marked = true ;
+                } else {
+                    from_marked = false ;
+                    cb_switch ( x , y );
+                }
+                break;
+            case CB_LEFT:
+                if ( !from_marked ) cb_switch ( x , y );
+                x--;
+                if ( x < 0 ) {
+                    x = 7;
+                    y++;
+                    if ( y == 8 ) y = 0;
+                }
+                if ( marked && ( marked_x == x ) && ( marked_y == y ) ) {
+                    from_marked = true ;
+                } else {
+                    from_marked = false ;
+                    cb_switch ( x , y );
+                }
+                break;
+            case CB_RIGHT:
+                if ( !from_marked ) cb_switch ( x , y );
+                x++;
+                if ( x == 8 ) {
+                    x = 0;
+                    y--;
+                    if ( y < 0 ) y = 7;
+                }
+                if ( marked && ( marked_x == x ) && ( marked_y == y ) ) {
+                    from_marked = true ;
+                } else {
+                    from_marked = false ;
+                    cb_switch ( x , y );
+                }
+                break;
+            case CB_SELECT:
 #ifdef CB_SELECT_PRE
                 if (lastbutton != CB_SELECT_PRE)
                     break;
 #endif
-                                if ( !marked ) {
-                                        xy2cr ( x , y , &c , &r );
+                if ( !marked ) {
+                    xy2cr ( x , y , &c , &r );
                     l = locn[r][c];
                     if ( ( color[l]!=computer ) && ( board[l]!=no_piece ) ) {
-                                            marked = true;
-                                            from_marked = true ;
-                                            marked_x = x;
-                                            marked_y = y;
-                                        }
-                                } else {
-                                        if ( ( marked_x == x ) && ( marked_y == y ) ) {
-                                                marked = false;
-                                                from_marked = false;
-                                        } else {
-                                                xy2cr ( marked_x , marked_y , &c , &r );
-                                                result.mv_s[0] = 'a' + c;
-                                                result.mv_s[1] = '1' + r;
-                                                xy2cr ( x , y , &c , &r );
-                                                result.mv_s[2] = 'a' + c;
-                                                result.mv_s[3] = '1' + r;
-                                                result.mv_s[4] = '\00';
-                                                result.type = COMMAND_MOVE;
-                                                return result;
-                                        }
-                                }
-                                break;
-                }
-                if (button != BUTTON_NONE)
+                        marked = true;
+                        from_marked = true ;
+                        marked_x = x;
+                        marked_y = y;
+                    }
+                } else {
+                    if ( ( marked_x == x ) && ( marked_y == y ) ) {
+                        marked = false;
+                        from_marked = false;
+                    } else {
+                        xy2cr ( marked_x , marked_y , &c , &r );
+                        result.mv_s[0] = 'a' + c;
+                        result.mv_s[1] = '1' + r;
+                        xy2cr ( x , y , &c , &r );
+                        result.mv_s[2] = 'a' + c;
+                        result.mv_s[3] = '1' + r;
+                        result.mv_s[4] = '\00';
+                        result.type = COMMAND_MOVE;
+                        return result;
+                    }
+                }
+                break;
+        }
+        if (button != BUTTON_NONE)
             lastbutton = button;
-        }
+    }
 
 }
 
@@ -432,77 +456,87 @@ struct cb_command cb_getcommand (void) {
 * plugin entry point.
 ******************************************************************************/
 enum plugin_status plugin_start(struct plugin_api* api, void* parameter) {
-        struct cb_command command;
-        /* init status */
-        bool exit = false;
-        
+    struct cb_command command;
+    /* init status */
+    bool exit = false;
+    
     /* plugin init */
     (void)parameter;
     rb = api;
     /* end of plugin init */
 
-        /* load opening book, soon */
-        
-        /* init board */
-        GNUChess_Initialize();
-        
-        /* draw the board */
-        /* I don't like configscreens, start game inmediatly */
-        cb_drawboard();
-        
-        while (!exit) {
-                if ( mate ) {
-                        rb->splash ( 500 , true , "Checkmate!" );
-                        rb->button_get(true);
-                        GNUChess_Initialize();
-                        cb_drawboard();
-                }
-                command = cb_getcommand ();
-                switch (command.type) {
-                        case COMMAND_MOVE:
-                                if ( ! VerifyMove ( command.mv_s , 0 , &command.mv ) ) {
-                                        rb->splash ( 50 , true , "Illegal move!" );
-                                        cb_drawboard();
-                                } else {
-                                        cb_drawboard();
-                                        rb->splash ( 0 , true , "Thinking..." );
+    /* load opening book, soon */
+    
+    /* init board */
+    GNUChess_Initialize();
+    
+    /* draw the board */
+    /* I don't like configscreens, start game inmediatly */
+    cb_drawboard();
+    
+    while (!exit) {
+        if ( mate ) {
+            rb->splash ( 500 , true , "Checkmate!" );
+            rb->button_get(true);
+            GNUChess_Initialize();
+            cb_drawboard();
+        }
+        command = cb_getcommand ();
+        switch (command.type) {
+            case COMMAND_MOVE:
+                if ( ! VerifyMove ( command.mv_s , 0 , &command.mv ) ) {
+                    rb->splash ( 50 , true , "Illegal move!" );
+                    cb_drawboard();
+                } else {
+                    cb_drawboard();
+                    rb->splash ( 0 , true , "Thinking..." );
 #ifdef HAVE_ADJUSTABLE_CPU_FREQ
-                                        rb->cpu_boost ( true );
+                    rb->cpu_boost ( true );
 #endif
-                                        SelectMove ( computer , 0 );
+                    SelectMove ( computer , 0 , cb_wt_callback );
 #ifdef HAVE_ADJUSTABLE_CPU_FREQ
-                                        rb->cpu_boost ( false );
+                    rb->cpu_boost ( false );
 #endif
-                                        cb_drawboard();
-                                }
-                                break;
-/*                      case COMMAND_RESTART:
-                                GNUChess_Initialize();
-                                cb_drawboard();
-                                break;*/
-                        case COMMAND_PLAY:
-                                opponent = !opponent; computer = !computer;
-                                rb->splash ( 0 , true , "Thinking..." );
+                    if ( wt_command == COMMAND_QUIT ) {
+                        exit = true;
+                        break;
+                    }
+                    cb_drawboard();
+                }
+                break;
+#if 0
+            case COMMAND_RESTART:
+                GNUChess_Initialize();
+                cb_drawboard();
+                break;
+#endif
+            case COMMAND_PLAY:
+                opponent = !opponent; computer = !computer;
+                rb->splash ( 0 , true , "Thinking..." );
 #ifdef HAVE_ADJUSTABLE_CPU_FREQ
-                                rb->cpu_boost ( true );
+                rb->cpu_boost ( true );
 #endif
-                                SelectMove ( computer , 0 );
+                SelectMove ( computer , 0 , cb_wt_callback );
 #ifdef HAVE_ADJUSTABLE_CPU_FREQ
-                                rb->cpu_boost ( false );
+                rb->cpu_boost ( false );
 #endif
-                                cb_drawboard();
-                                break;
-                        case COMMAND_LEVEL:
-                                cb_levelup ( );
-                                cb_drawboard();
-                                break;
-                        case COMMAND_QUIT:
-                                /*cb_saveposition();*/
-                                exit = true;
-                                break;
-                }
-        }
-        
+                if ( wt_command == COMMAND_QUIT ) {
+                    exit = true;
+                    break;
+                }
+                cb_drawboard();
+                break;
+            case COMMAND_LEVEL:
+                cb_levelup ( );
+                cb_drawboard();
+                break;
+            case COMMAND_QUIT:
+                /*cb_saveposition();*/
+                exit = true;
+                break;
+        }
+    }
+    
     rb->lcd_setfont(FONT_UI);
     return PLUGIN_OK;
 }
diff --git a/apps/plugins/chessbox/gnuchess.c b/apps/plugins/chessbox/gnuchess.c
index 879c083ce7..9bd07c8eee 100644
--- a/apps/plugins/chessbox/gnuchess.c
+++ b/apps/plugins/chessbox/gnuchess.c
@@ -279,7 +279,8 @@ void CopyBoard( short a[64] , short b[64] );
 void OpeningBook ( void );
 int  search ( short side, short ply, short depth,
               short alpha, short beta,
-                          unsigned short bstline[], short *rpt );
+                          unsigned short bstline[], short *rpt,
+              void (*callback)(void) );
 int  evaluate ( short side, short xside, short ply, short depth,
                 short alpha, short beta );
 int  ProbeTTable ( short side, short depth,
@@ -333,9 +334,6 @@ short pscore[3];
   xside = otherside[side];
   pscore[white] = pscore[black] = 0;
 
-  /* ok, I will yield here for lower levels */
-  rb->yield();
-
   for (c1 = white; c1 <= black; c1++)
     {
       c2 = otherside[c1];
@@ -1018,8 +1016,7 @@ register int sq;
 /* ............    MOVE GENERATION & SEARCH ROUTINES    .............. */
 
 
-int SelectMove(side,iop)
-short side,iop;
+int SelectMove( short side, short iop , void (*callback)(void))
 
 /*
    Select a move by calling function search() at progressively deeper 
@@ -1078,21 +1075,21 @@ static short i,alpha,beta,score,tempb,tempc,tempsf,tempst,xside,rpt;
     {
       Sdepth++;
       /*ShowDepth(' ');*/
-      score = search(side,1,Sdepth,alpha,beta,PrVar,&rpt);
+      score = search(side,1,Sdepth,alpha,beta,PrVar,&rpt,callback);
       for (i = 1; i <= Sdepth; i++) killr0[i] = PrVar[i];
       if (score < alpha && !timeout)
         {
           /*ShowDepth('-');*/
           ExtraTime = 10*ResponseTime;
           ZeroTTable();
-          score = search(side,1,Sdepth,-9000,beta,PrVar,&rpt);
+          score = search(side,1,Sdepth,-9000,beta,PrVar,&rpt,callback);
         }
       if (score > beta && !timeout && !(root->flags & exact))
         {
           /*ShowDepth('+');*/
           ExtraTime = 0;
           ZeroTTable();
-          score = search(side,1,Sdepth,alpha,9000,PrVar,&rpt);
+          score = search(side,1,Sdepth,alpha,9000,PrVar,&rpt,callback);
         }
       score = root->score;
       if (!timeout)
@@ -1209,9 +1206,9 @@ struct BookEntry *p;
     }\
 }
 
-int search(side,ply,depth,alpha,beta,bstline,rpt)
-short side,ply,depth,alpha,beta,*rpt;
-unsigned short bstline[];
+int search( short side, short ply, short depth,
+            short alpha, short beta, unsigned short bstline[], short *rpt,
+            void (*callback)(void) )
 
 /*
    Perform an alpha-beta search to determine the score for the current 
@@ -1238,8 +1235,10 @@ short xside,pbst,d,e,cf,score,rcnt;
 unsigned short mv,nxtline[maxdepth];
 struct leaf *node,tmp;
 
-  /* ok, I will yield here for higher levels */
+  /* this is the only place we need to yield */
   rb->yield();
+  /* and check for user interaction */
+  callback();
 
   NodeCnt++;
   xside = otherside[side];
@@ -1308,7 +1307,7 @@ struct leaf *node,tmp;
           PawnThreat[ply] = (node->flags & pwnthrt);
           Tscore[ply] = node->score;
           node->score = -search(xside,ply+1,depth-1,-beta,-alpha,
-                                nxtline,&rcnt);
+                                nxtline,&rcnt,callback);
           if (abs(node->score) > 9000) node->flags |= exact;
           else if (rcnt == 1) node->score /= 2;
           if (rcnt >= 2 || GameCnt-Game50 > 99 ||
diff --git a/apps/plugins/chessbox/gnuchess.h b/apps/plugins/chessbox/gnuchess.h
index 68ef9f9a81..e94748919a 100644
--- a/apps/plugins/chessbox/gnuchess.h
+++ b/apps/plugins/chessbox/gnuchess.h
@@ -26,6 +26,7 @@ extern short board[64];
 extern short color[64];
 extern long Level;
 extern short TCflag,TCmoves,TCminutes;
+extern short timeout;
 
 /* ---- RockBox integration ---- */
 extern struct plugin_api* rb;
@@ -33,8 +34,7 @@ extern struct plugin_api* rb;
 /* ---- The beginning of a GNUChess v2 APIfication ---- */
 void SetTimeControl(void);
 void GNUChess_Initialize(void);
-int VerifyMove(char s[],short iop,unsigned short *mv);
-int  SelectMove ( short side, short iop);
-
+int  VerifyMove(char s[],short iop,unsigned short *mv);
+int  SelectMove ( short side, short iop , void (*callback)(void) );
 
 #endif