import 'package:flutter/material.dart';
import 'package:webview_flutter/webview_flutter.dart';

class CalendarScreen extends StatefulWidget {
  const CalendarScreen({super.key});

  @override
  State<CalendarScreen> createState() => _CalendarScreenState();
}

class _CalendarScreenState extends State<CalendarScreen> {
  late final WebViewController _controller;
  bool _isLoading = true;
  bool _hasError = false;

  @override
  void initState() {
    super.initState();
    _controller = WebViewController()
      ..setJavaScriptMode(JavaScriptMode.unrestricted)
      ..setNavigationDelegate(
        NavigationDelegate(
          onPageStarted: (_) => setState(() {
            _isLoading = true;
            _hasError = false;
          }),
          onPageFinished: (_) => setState(() => _isLoading = false),
          onWebResourceError: (error) => setState(() {
            _hasError = true;
            _isLoading = false;
          }),
        ),
      )
      ..loadRequest(Uri.parse(
          'https://calendar.google.com/calendar/u/0/embed?src=b9c267252d5be63d5cdc880be499885a88421eefd0e34e1392890daba0d8471e@group.calendar.google.com&ctz=Europe/Belgrade'));
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Stack(
        children: [
          WebViewWidget(controller: _controller),
          if (_isLoading)
            const Center(child: CircularProgressIndicator()),
          if (_hasError)
            Center(
              child: Column(
                mainAxisAlignment: MainAxisAlignment.center,
                children: [
                  const Text(
                    "Failed to load Google Calendar.",
                    style: TextStyle(fontSize: 18, fontWeight: FontWeight.bold),
                  ),
                  const SizedBox(height: 10),
                  ElevatedButton(
                    onPressed: () => _controller.reload(),
                    child: const Text("Retry"),
                  ),
                ],
              ),
            ),
        ],
      ),
    );
  }
}