import 'package:flutter/material.dart';
import 'package:flutter_svg/flutter_svg.dart';
import 'package:photo_view/photo_view.dart';

import '../api/errors/error_mapper.dart';
import 'a11y/a11y_labels.dart';
import 'app_progress_indicator.dart';
import 'placeholder_view.dart';
import 'user_avatar.dart';

/// Full-screen avatar. Loads the bytes itself instead of handing the URL to an
/// [ImageProvider]: Nextcloud and Spreed serve generated avatars as SVG, which
/// no codec can decode ("Invalid image data") — those get an [SvgPicture]
/// instead of the zoomable [PhotoView].
class LargeProfilePictureView extends StatefulWidget {
  final String id;
  final bool isGroup;

  const LargeProfilePictureView({
    required this.id,
    this.isGroup = false,
    super.key,
  });

  @override
  State<LargeProfilePictureView> createState() =>
      _LargeProfilePictureViewState();
}

class _LargeProfilePictureViewState extends State<LargeProfilePictureView> {
  late Future<AvatarPayload?> _payload;

  @override
  void initState() {
    super.initState();
    _payload = loadAvatarPayload(
      id: widget.id,
      isGroup: widget.isGroup,
      size: 1024,
    );
  }

  @override
  Widget build(BuildContext context) {
    final label = widget.isGroup
        ? A11yLabels.groupPicture
        : A11yLabels.profilePicture;
    final background = Theme.of(context).colorScheme.surface;

    return Scaffold(
      appBar: AppBar(title: Text(label)),
      body: Semantics(
        image: true,
        label: label,
        child: FutureBuilder<AvatarPayload?>(
          future: _payload,
          builder: (context, snapshot) {
            if (snapshot.connectionState != ConnectionState.done) {
              return const Center(child: AppProgressIndicator.large());
            }
            final payload = snapshot.data;
            if (snapshot.hasError) {
              return PlaceholderView(
                icon: Icons.broken_image_outlined,
                text: errorToUserMessage(snapshot.error),
              );
            }
            // No avatar on the server — the same icon the small avatar shows.
            if (payload == null) {
              return PlaceholderView(
                icon: widget.isGroup ? Icons.group : Icons.person,
                text: 'Kein Bild hinterlegt.',
              );
            }
            if (payload.isSvg) {
              return ColoredBox(
                color: background,
                child: InteractiveViewer(
                  minScale: 0.5,
                  maxScale: 3,
                  child: SvgPicture.memory(payload.bytes, fit: BoxFit.contain),
                ),
              );
            }
            return PhotoView(
              minScale: 0.5,
              maxScale: 3.0,
              imageProvider: MemoryImage(payload.bytes),
              backgroundDecoration: BoxDecoration(color: background),
            );
          },
        ),
      ),
    );
  }
}