[Add] Window focus and event routing.

client/src/main.cpp

@@ -81,9 +81,7 @@ int main(int argc, char** argv) {
     SDL_Event event;
     while(SDL_PollEvent(&event)) {
       if(event.type == SDL_EVENT_QUIT) { running = false; }
-      /* Pass input to terminal. */
       desktop->handle_event(&event);
-      term->handle_input(&event);
     }
 
     /* Clear screen. */

client/src/ui/desktop.cpp

@@ -1,9 +1,14 @@
+#include <algorithm>
+
 #include "desktop.h"
+#include <SDL3/SDL_events.h>
 #include "gfx/shape_renderer.h"
 #include "gfx/txt_renderer.h"
 #include "ui/ui_window.h"
 
-Desktop::Desktop(void) {}
+Desktop::Desktop(void) {
+  _focused_window = nullptr;
+}
 
 /* Desktop won't own the windows, so doesn't delete them. */
 Desktop::~Desktop(void) {}
@@ -13,11 +18,36 @@ void Desktop::add_window(UIWindow* window) {
 }
 
 void Desktop::handle_event(SDL_Event* event) {
-  /* Just pass the even to all windows for the moment.
-   * TODO: Only send event to the focused window.
-   */
-  for(auto win : _windows) {
-    win->handle_event(event);
+  if(event->type == SDL_EVENT_MOUSE_BUTTON_DOWN) {
+    int mouse_x = event->button.x;
+    int mouse_y = event->button.y;
+
+    /* Find the top-most window that was clicked. */
+    for(int i = _windows.size()-1; i >= 0; --i) {
+      if(_windows[i]->is_point_inside(mouse_x, mouse_y)) {
+        /* If not focused, focus it. */
+        if(_windows[i] != _focused_window) {
+          if(_focused_window) {
+            _focused_window->set_focused(false);
+          }
+          _focused_window = _windows[i];
+          _focused_window->set_focused(true);
+
+          /* Move window to the front. */
+          _windows.erase(_windows.begin() + i);
+          _windows.push_back(_focused_window);
+        }
+        break;
+      }
+    }
+  }
+
+  if(_focused_window) {
+    _focused_window->handle_event(event);
+    Terminal* content = _focused_window->get_content();
+    if(content && (event->type == SDL_EVENT_TEXT_INPUT || event->type == SDL_EVENT_KEY_DOWN)) {
+      content->handle_input(event);
+    }
   }
 }
 

client/src/ui/desktop.h

@@ -18,4 +18,5 @@ public:
 
 private:
   std::vector<UIWindow*> _windows;
+  UIWindow* _focused_window;
 };

client/src/ui/ui_window.cpp

@@ -11,12 +11,26 @@ UIWindow::UIWindow(const char* title, int x, int y, int width, int height) {
   _height       = height;
   _content      = nullptr;
   _is_dragging  = false;
+  _is_focused   = false; /* Not focused by default? */
 }
 
 void UIWindow::set_content(Terminal* term) {
   _content = term;
 }
 
+void UIWindow::set_focused(bool focused) {
+  _is_focused = focused;
+}
+
+Terminal* UIWindow::get_content(void) {
+  return _content;
+}
+
+bool UIWindow::is_point_inside(int x, int y) {
+  return (x >= _x && x <= _x + _width &&
+          y >= _y && y <= _y + _height);
+}
+
 void UIWindow::render(ShapeRenderer* shape_renderer, TextRenderer* txt_renderer,
                       int screen_height) {
   int title_bar_height = 30;
@@ -24,6 +38,7 @@ void UIWindow::render(ShapeRenderer* shape_renderer, TextRenderer* txt_renderer,
   /* Define colours. */
   float frame_color[]             = { 0.2f,  0.2f,  0.25f };
   float title_bar_color[]         = { 0.15f, 0.15f, 0.2f  };
+  float focused_title_bar_color[] = { 0.3f, 0.3f, 0.4f };
   float title_text_color[]        = { 0.9f,  0.9f,  0.9f  };
 
   /* Convert top-left coords to bottom-left for OpenGL. */
@@ -33,8 +48,13 @@ void UIWindow::render(ShapeRenderer* shape_renderer, TextRenderer* txt_renderer,
   shape_renderer->draw_rect(_x, y_gl, _width, _height, frame_color);
 
   /* Draw title bar. */
+  if(_is_focused) {
+    shape_renderer->draw_rect(_x, y_gl+_height-title_bar_height, _width, title_bar_height,
+                              focused_title_bar_color);
+  } else {
     shape_renderer->draw_rect(_x, y_gl+_height-title_bar_height, _width, title_bar_height,
                               title_bar_color);
+  }
 
   /* Draw title text. */
   txt_renderer->render_text(_title.c_str(), _x+5, y_gl+_height-title_bar_height+8,

client/src/ui/ui_window.h

@@ -12,12 +12,16 @@ public:
 
   void render(ShapeRenderer* shape_renderer, TextRenderer* txt_renderer, int screen_height);
   void handle_event(SDL_Event* event);
+  void set_focused(bool focused);
+  bool is_point_inside(int x, int y);
   void set_content(Terminal* term);
+  Terminal* get_content(void);
 
 private:
   int _x, _y, _width, _height;
   std::string _title;
   Terminal* _content;
+  bool _is_focused; /* Managed by desktop. */
 
   bool _is_dragging;
   int _drag_offset_x, _drag_offset_y;