Provide both enter_action and exit_action

Author: lefticus

src/game.cpp

@@ -56,9 +56,12 @@ Game_Map make_map()// NOLINT cognitive complexity
     return direction == Direction::South;
   };
 
-  map.locations.at(Point{0,3}).action = [](Game &game, Point, Direction) {
+  map.locations.at(Point{0,3}).enter_action = [](Game &game, Point, Direction) {
     game.last_message = "There is a secret entrance to the north";
   };
+  map.locations.at(Point{ 0, 3 }).exit_action = [](Game &game, Point, Direction) {
+    game.last_message = "";
+  };
 
 
   return map;

src/game_components.hpp

@@ -19,7 +19,8 @@ enum struct Direction { North, South, East, West };
 
 struct Location
 {
-  std::function<void(Game &, Point, Direction)> action;
+  std::function<void(Game &, Point, Direction)> enter_action;
+  std::function<void(Game &, Point, Direction)> exit_action;
   std::function<void(Vector2D_Span<Color> &, const Game &, Point)> draw;
   std::function<bool(const Game &, Point, Direction)> can_enter;
 };

src/main.cpp

@@ -70,7 +70,7 @@ void draw(Bitmap &viewport, const Game &game)
   }
 }
 
-void game_iteration_canvas()
+void game_iteration_canvas()// NOLINT cognitive complexity
 {
   auto game = make_game();
 
@@ -104,6 +104,8 @@ void game_iteration_canvas()
     [&] {
       if (current_event != last_event) {
         auto location = game.player.map_location;
+        const auto last_location = location;
+
         Direction from{};
 
         if (current_event == ftxui::Event::ArrowUp) {
@@ -123,11 +125,15 @@ void game_iteration_canvas()
         }
 
         if (game.maps.at(game.current_map).can_enter_from(game, location, from)) {
+          auto exit_action = game.maps.at(game.current_map).locations.at(last_location).exit_action;
+          if (exit_action) { exit_action(game, last_location, from); }
+
           game.player.map_location = location;
-          auto action = game.maps.at(game.current_map).locations.at(location).action;
 
-          if (action) { action(game, location, from); }
+          auto enter_action = game.maps.at(game.current_map).locations.at(location).enter_action;
+          if (enter_action) { enter_action(game, location, from); }
         }
+
       }
     }();