import 'dart:ui_web' as ui_web;

import 'package:flutter/material.dart';
import 'package:url_launcher/url_launcher.dart';
import 'package:web/web.dart' as web;

/// Embedded iframe view for displaying external content (web only).
///
/// Uses HtmlElementView for Flutter web to embed an iframe.
/// Includes a header bar with title, refresh, open in new tab, and close actions.
class IframeView extends StatefulWidget {
  const IframeView({
    super.key,
    required this.url,
    required this.title,
    required this.onClose,
  });

  /// URL to display in the iframe.
  final String url;

  /// Title displayed in the header bar.
  final String title;

  /// Callback when the close button is pressed.
  final VoidCallback onClose;

  @override
  State<IframeView> createState() => _IframeViewState();
}

class _IframeViewState extends State<IframeView> {
  late final String _viewType;
  late web.HTMLIFrameElement _iframe;
  bool _isLoading = true;

  @override
  void initState() {
    super.initState();
    _viewType = 'iframe-${widget.url.hashCode}-${DateTime.now().millisecondsSinceEpoch}';
    _createIframe();
  }

  void _createIframe() {
    _iframe = web.document.createElement('iframe') as web.HTMLIFrameElement
      ..src = widget.url
      ..style.border = 'none'
      ..style.width = '100%'
      ..style.height = '100%'
      ..allow = 'fullscreen';

    _iframe.onLoad.listen((_) {
      if (mounted) {
        setState(() => _isLoading = false);
      }
    });

    // Register the view factory
    ui_web.platformViewRegistry.registerViewFactory(
      _viewType,
      (int viewId) => _iframe,
    );
  }

  void _refresh() {
    setState(() => _isLoading = true);
    // Reload the iframe by setting src again
    _iframe.src = widget.url;
  }

  Future<void> _openInNewTab() async {
    final uri = Uri.tryParse(widget.url);
    if (uri != null && await canLaunchUrl(uri)) {
      await launchUrl(uri, mode: LaunchMode.externalApplication);
    }
  }

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

    return Column(
      children: [
        // Header bar
        Container(
          height: 56,
          padding: const EdgeInsets.symmetric(horizontal: 16),
          decoration: BoxDecoration(
            color: colorScheme.surfaceContainerHighest,
            border: Border(
              bottom: BorderSide(color: colorScheme.outlineVariant),
            ),
          ),
          child: Row(
            children: [
              // Title
              Expanded(
                child: Text(
                  widget.title,
                  style: textTheme.titleSmall?.copyWith(
                    fontWeight: FontWeight.w600,
                  ),
                  overflow: TextOverflow.ellipsis,
                ),
              ),
              // Actions
              IconButton(
                icon: const Icon(Icons.open_in_new, size: 20),
                tooltip: 'Open in new tab',
                onPressed: _openInNewTab,
              ),
              IconButton(
                icon: const Icon(Icons.refresh, size: 20),
                tooltip: 'Refresh',
                onPressed: _refresh,
              ),
              IconButton(
                icon: const Icon(Icons.close, size: 20),
                tooltip: 'Close',
                onPressed: widget.onClose,
              ),
            ],
          ),
        ),
        // Iframe content
        Expanded(
          child: Stack(
            children: [
              HtmlElementView(viewType: _viewType),
              // Loading overlay
              if (_isLoading)
                Container(
                  color: colorScheme.surface,
                  child: const Center(
                    child: CircularProgressIndicator(),
                  ),
                ),
            ],
          ),
        ),
      ],
    );
  }
}