Split the game core and ui code into their respective modules

Game state struct ends the variable mess in main.c

ui.c

@@ -0,0 +1,47 @@
+#include "ui.h"
+#include "game.h"
+#include <math.h>
+#include <raylib.h>
+#include <stdbool.h>
+
+static bool is_dragging;
+static Vector2 drag_start_pos;
+
+void handle_mouse_input(GameState_t *game_state) {
+  if (IsMouseButtonPressed(MOUSE_LEFT_BUTTON)) {
+    drag_start_pos = GetMousePosition();
+    if (drag_start_pos.x >= 500 && drag_start_pos.x <= 775 && drag_start_pos.y >= 455 && drag_start_pos.y <= 479) {
+      reset_board(game_state);
+      return;
+    }
+
+    is_dragging = true;
+  } else if (IsMouseButtonReleased(MOUSE_LEFT_BUTTON) && is_dragging) {
+    Vector2 current_pos = GetMousePosition();
+
+    float dx = current_pos.x - drag_start_pos.x;
+    float dy = current_pos.y - drag_start_pos.y;
+
+    float drag_distance = sqrt(dx * dx + dy * dy);
+
+    // We don't want to register single clicks as a move
+    if (drag_distance >= 30) {
+      if (fabs(dx) > fabs(dy)) {
+        if (dx > 0) {
+          move(game_state, RIGHT);
+        } else {
+          move(game_state, LEFT);
+        }
+      } else {
+        if (dy > 0) {
+          move(game_state, DOWN);
+        } else {
+          move(game_state, UP);
+        }
+      }
+      spawn_tile(game_state);
+    }
+
+    is_dragging = false;
+  }
+}