Improve keybind options UX

Changelog:
- Deal with set key to already binded key
    - Binded key will null the existing key
    - Non-binded will be reset back
- Colour code the options during and after key bind changes

engine/keymaps.c

@@ -151,5 +151,10 @@ const char* ExtGetKeyName(int key)
         return "SPACE";
     }
 
+    if (key == KEY_NULL)
+    {
+        return "NONE";
+    }
+
     return "";
 }

scenes/options_scene.c

@@ -55,7 +55,7 @@ static void options_scene_render_func(Scene_t* scene)
 
     Sprite_t* level_board = get_sprite(&scene->engine->assets, "lvl_board");
 #define TITLE_FONT_SIZE 40
-#define FONT_SIZE 24
+#define FONT_SIZE 22
 #define FONT_COLOUR BLACK
     float start_x = scene->engine->intended_window_size.x / 2;
     start_x -= level_board->frame_size.x / 2;
@@ -84,16 +84,27 @@ static void options_scene_render_func(Scene_t* scene)
             {
                 DrawTextEx(*menu_font, ">>", (Vector2){start_x,y_offset}, FONT_SIZE, 4, BLACK);
             }
+
+            bool changed = false;
             if (keybind_info.key == keybind_info.original_key)
             {
                 sprintf(buffer, "%s : %s", keybind_info.action_name, keybind_info.key_name);
-                DrawTextEx(*menu_font, buffer, (Vector2){start_x+32, y_offset}, FONT_SIZE, 4, BLACK);
             }
             else
             {
+                changed = true;
                 sprintf(buffer, "%s : %s => %s", keybind_info.action_name, keybind_info.original_key_name, keybind_info.key_name);
-                DrawTextEx(*menu_font, buffer, (Vector2){start_x+32, y_offset}, FONT_SIZE, 4, BLUE);
             }
+
+            if (data->mode == OPTIONS_KEYBIND_MODE && line == data->curr_selection)
+            {
+                DrawTextEx(*menu_font, buffer, (Vector2){start_x+32, y_offset}, FONT_SIZE, 4, RED);
+            }
+            else
+            {
+                DrawTextEx(*menu_font, buffer, (Vector2){start_x+32, y_offset}, FONT_SIZE, 4, changed? BLUE : BLACK);
+            }
+
             y_offset += FONT_SIZE;
             line++;
         }
@@ -120,6 +131,11 @@ static void options_scene_render_func(Scene_t* scene)
             y_offset += FONT_SIZE;
             DrawTextEx(*menu_font, "Press a Key...", (Vector2){start_x+32, y_offset}, FONT_SIZE, 4, BLACK);
         }
+        y_offset += FONT_SIZE;
+        if (data->keybind_status == 1)
+        {
+            DrawTextEx(*menu_font, "Reserved key! Try another key.", (Vector2){start_x+32, y_offset}, FONT_SIZE, 4, RED);
+        }
     
     EndTextureMode();
 }
@@ -149,14 +165,51 @@ static void wait_for_keymap_input(Scene_t* scene)
         return;
     }
 
-    if (scene->engine->last_input_key == KEY_NULL)
+    int new_key = scene->engine->last_input_key;
+    if (new_key == KEY_NULL)
     {
         return;
     }
 
-    data->keybinds_info.elems[data->curr_selection - 1].key = scene->engine->last_input_key;
-    data->keybinds_info.elems[data->curr_selection - 1].key_name = ExtGetKeyName(scene->engine->last_input_key);
+    // Invalid/Reserved key are empty strings
+    if (ExtGetKeyName(new_key)[0] == 0)
+    {
+        data->keybind_status = 1;
+        return;
+    }
 
+    {
+        // To check for keys already set by new_key
+        // Also to fill in any KEY_NULL if the original key is not new key
+        // Requires the index to modify the current element
+        KeyBindInfo_t info;
+        size_t i = 0;
+
+        sc_array_foreach(&data->keybinds_info, info)
+        {
+            if (info.key == new_key)
+            {
+                data->keybinds_info.elems[i].key = data->keybinds_info.elems[i].original_key;
+                data->keybinds_info.elems[i].key_name = ExtGetKeyName(data->keybinds_info.elems[i].key);
+                if (info.original_key == new_key)
+                {
+                    data->keybinds_info.elems[i].key = KEY_NULL;
+                    data->keybinds_info.elems[i].key_name = ExtGetKeyName(data->keybinds_info.elems[i].key);
+                }
+            }
+            else if (info.key == KEY_NULL)
+            {
+                data->keybinds_info.elems[i].key = data->keybinds_info.elems[i].original_key;
+                data->keybinds_info.elems[i].key_name = ExtGetKeyName(data->keybinds_info.elems[i].key);
+            }
+            i++;
+        }
+    }
+
+    data->keybinds_info.elems[data->curr_selection - 1].key = new_key;
+    data->keybinds_info.elems[data->curr_selection - 1].key_name = ExtGetKeyName(new_key);
+
+    data->keybind_status = 0;
     data->mode = OPTIONS_NORMAL_MODE;
 }
 
@@ -281,6 +334,7 @@ static void reset_options_scene(Scene_t* scene)
     }
     data->curr_selection = 0;
     data->mode = OPTIONS_NORMAL_MODE;
+    data->keybind_status = 0;
 }
 
 static void options_action_remap_func(Scene_t* scene)

scenes/scene_impl.h

@@ -155,6 +155,7 @@ sc_array_def(KeyBindInfo_t, keybinds);
 
 typedef struct OptionSceneData {
     struct sc_array_keybinds keybinds_info; // Selection index -> keybind info
+    int keybind_status;
     uint16_t n_selections;
     uint16_t curr_selection;
     OptionSceneMode_t mode;