AppFlowy/frontend/appflowy_flutter/lib/shared/window_title_bar.dart

import 'package:flutter/material.dart';

import 'package:appflowy_editor/appflowy_editor.dart';
import 'package:flowy_infra_ui/widget/spacing.dart';
import 'package:window_manager/window_manager.dart';

class WindowsButtonListener extends WindowListener {
  WindowsButtonListener();

  final ValueNotifier<bool> isMaximized = ValueNotifier(false);

  @override
  void onWindowMaximize() => isMaximized.value = true;

  @override
  void onWindowUnmaximize() => isMaximized.value = false;

  void dispose() => isMaximized.dispose();
}

class WindowTitleBar extends StatefulWidget {
  const WindowTitleBar({
    super.key,
    this.leftChildren = const [],
  });

  final List<Widget> leftChildren;

  @override
  State<WindowTitleBar> createState() => _WindowTitleBarState();
}

class _WindowTitleBarState extends State<WindowTitleBar> {
  late final WindowsButtonListener? windowsButtonListener;
  bool isMaximized = false;

  @override
  void initState() {
    super.initState();

    if (PlatformExtension.isWindows || PlatformExtension.isLinux) {
      windowsButtonListener = WindowsButtonListener();
      windowManager.addListener(windowsButtonListener!);
      windowsButtonListener!.isMaximized.addListener(() {
        if (mounted) {
          setState(
            () => isMaximized = windowsButtonListener!.isMaximized.value,
          );
        }
      });
    } else {
      windowsButtonListener = null;
    }

    windowManager.isMaximized().then(
          (v) => mounted ? setState(() => isMaximized = v) : null,
        );
  }

  @override
  void dispose() {
    if (windowsButtonListener != null) {
      windowManager.removeListener(windowsButtonListener!);
      windowsButtonListener?.dispose();
    }
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final brightness = Theme.of(context).brightness;

    return Container(
      height: 40,
      decoration: BoxDecoration(
        color: Theme.of(context).colorScheme.surfaceContainerHighest,
      ),
      child: DragToMoveArea(
        child: Row(
          children: [
            const HSpace(4),
            ...widget.leftChildren,
            const Spacer(),
            WindowCaptionButton.minimize(
              brightness: brightness,
              onPressed: () => windowManager.minimize(),
            ),
            if (isMaximized) ...[
              WindowCaptionButton.unmaximize(
                brightness: brightness,
                onPressed: () => windowManager.unmaximize(),
              ),
            ] else ...[
              WindowCaptionButton.maximize(
                brightness: brightness,
                onPressed: () => windowManager.maximize(),
              ),
            ],
            WindowCaptionButton.close(
              brightness: brightness,
              onPressed: () => windowManager.close(),
            ),
          ],
        ),
      ),
    );
  }
}