crossbow:: checkmate rule

checkmove.cpp

@@ -338,6 +338,8 @@ EX void checkmove() {
     }
 #endif
 
+  if(!canmove && bow::crossbow_mode()) canmove = bow::have_bow_target();
+
   if(!canmove) {
     achievement_final(true);
     if(cmode & sm::NORMAL) showMissionScreen();

crossbow.cpp

@@ -297,6 +297,30 @@ EX void shoot() {
   gen_bowpath_map();
   }
 
+EX bool have_bow_target() {
+  dynamicval<decltype(bowpath)> bp(bowpath);
+  dynamicval<decltype(bowpath_map)> bpm(bowpath_map);
+
+  for(int i=0; i<isize(dcal); i++) {
+    cell *c = dcal[i];
+    target_at = {};
+    target_at[c->cpdist] = {c};
+
+    int res = create_path();
+    if(res == -1) continue;
+
+    checked_move_issue = miVALID;
+    pcmove pcm;
+    pcm.checkonly = true;
+    changes.init(true);
+    bool b = pcm.try_shooting(false);
+    changes.rollback();
+
+    if(b) return true;
+    }
+  return false;
+  }
+
 EX void showMenu() {
   cmode = sm::SIDE | sm::MAYDARK;
   gamescreen();

pcmove.cpp

@@ -332,7 +332,7 @@ bool pcmove::movepcto() {
     changes.rollback();
     if(!checkonly) flipplayer = false;
 
-    if(!b && items[itCrossbow] == 0 && bow::crossbow_mode() && !bow::fire_mode && d >= 0) {
+    if(!b && items[itCrossbow] == 0 && bow::crossbow_mode() && !bow::fire_mode && d >= 0 && !checkonly) {
       changes.init(checkonly);
       changes.value_keep(bow::bowpath_map);
       b = try_shooting(true);