import 'package:flutter/material.dart';

import '../api.dart';
import '../browser.dart' as browser;
import '../main.dart';
import 'ui.dart';

/// LT file management for one KC: upload with a visibility tier + list.
class FilesAdminScreen extends StatefulWidget {
  const FilesAdminScreen({super.key, required this.kcId});
  final String kcId;

  @override
  State<FilesAdminScreen> createState() => _FilesAdminScreenState();
}

class _FilesAdminScreenState extends State<FilesAdminScreen> {
  Future<List<FileEntry>>? _files;
  bool _uploading = false;
  Api get _api => AppScope.of(context).api;

  static const _visibilities = {
    'ALLE': 'Alle (inkl. Konfis)',
    'ALLE_AUSSER_KONFIS': 'Team (ohne Konfis)',
    'NUR_LT': 'Nur Leitungsteam',
  };

  @override
  void didChangeDependencies() {
    super.didChangeDependencies();
    _files ??= _api.files(widget.kcId);
  }

  void _reload() => setState(() => _files = _api.files(widget.kcId));

  Future<void> _upload() async {
    final api = _api;
    final picked = await browser.pickFile();
    if (picked == null || !mounted) return;
    final visibility = await showDialog<String>(
      context: context,
      builder: (_) => SimpleDialog(
        title: Text('Sichtbarkeit für „${picked.name}“'),
        children: [
          for (final e in _visibilities.entries)
            SimpleDialogOption(
              onPressed: () => Navigator.of(context).pop(e.key),
              child: Text(e.value),
            ),
        ],
      ),
    );
    if (visibility == null || !mounted) return;
    setState(() => _uploading = true);
    try {
      await api.uploadFile(widget.kcId, picked.name, picked.bytes, visibility);
      if (mounted) _reload();
    } catch (e) {
      if (mounted) toast(context, '$e');
    } finally {
      if (mounted) setState(() => _uploading = false);
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(title: const Text('Dateien (LT)')),
      floatingActionButton: FloatingActionButton.extended(
        onPressed: _uploading ? null : _upload,
        icon: _uploading
            ? const SizedBox(
                height: 18, width: 18, child: CircularProgressIndicator(strokeWidth: 2))
            : const Icon(Icons.upload_file),
        label: const Text('Hochladen'),
      ),
      body: FutureBuilder<List<FileEntry>>(
        future: _files,
        builder: (context, snap) {
          if (snap.connectionState != ConnectionState.done) {
            return const Center(child: CircularProgressIndicator());
          }
          if (snap.hasError) return ErrorText('${snap.error}', onRetry: _reload);
          final files = snap.data!;
          if (files.isEmpty) {
            return const Center(child: Text('Noch keine Dateien.'));
          }
          return ListView(
            children: [
              for (final f in files)
                ListTile(
                  leading: const Icon(Icons.insert_drive_file_outlined),
                  title: Text(f.filename),
                  subtitle: Text(_visibilities[f.visibility] ?? f.visibility),
                ),
            ],
          );
        },
      ),
    );
  }
}