import 'dart:async';

import 'package:fintracker_api/fintracker_api.dart';
import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';

import '../../portfolio/labels.dart' show assetClassLabel;
import '../providers.dart';

/// Search-and-pick over `GET /instruments?q=`. Deliberately dumb: it shows what the search
/// returned and nothing else — no "probably this one" pre-selection, no highlighted best
/// guess. The binding is the user's statement, not the app's inference.
class LinkInstrumentDialog extends ConsumerStatefulWidget {
  const LinkInstrumentDialog({required this.initialQuery, super.key});

  /// Prefilled search text (the ISIN or ticker from the report). It only fills the search
  /// box — nothing is selected until the user taps a row.
  final String initialQuery;

  @override
  ConsumerState<LinkInstrumentDialog> createState() =>
      _LinkInstrumentDialogState();
}

class _LinkInstrumentDialogState extends ConsumerState<LinkInstrumentDialog> {
  late final TextEditingController _controller = TextEditingController(
    text: widget.initialQuery,
  );
  String _query = '';
  Timer? _debounce;

  @override
  void initState() {
    super.initState();
    _query = widget.initialQuery;
  }

  @override
  void dispose() {
    _debounce?.cancel();
    _controller.dispose();
    super.dispose();
  }

  void _onChanged(String value) {
    _debounce?.cancel();
    _debounce = Timer(const Duration(milliseconds: 350), () {
      if (mounted) setState(() => _query = value);
    });
  }

  @override
  Widget build(BuildContext context) {
    final results = ref.watch(instrumentSearchProvider(_query));
    return AlertDialog(
      title: const Text('Привязать к инструменту'),
      content: SizedBox(
        width: 520,
        height: 420,
        child: Column(
          children: [
            TextField(
              controller: _controller,
              autofocus: true,
              decoration: const InputDecoration(
                prefixIcon: Icon(Icons.search),
                hintText: 'Тикер, ISIN или название',
                border: OutlineInputBorder(),
                isDense: true,
              ),
              onChanged: _onChanged,
            ),
            const SizedBox(height: 12),
            Expanded(
              child: results.when(
                loading: () => const Center(child: CircularProgressIndicator()),
                error: (e, _) => Center(child: Text('$e')),
                data: (rows) {
                  if (_query.trim().length < 2) {
                    return const Center(
                      child: Text('Введите минимум 2 символа'),
                    );
                  }
                  if (rows.isEmpty) {
                    return const Center(child: Text('Ничего не найдено'));
                  }
                  return ListView.builder(
                    itemCount: rows.length,
                    itemBuilder: (context, i) => _row(rows[i]),
                  );
                },
              ),
            ),
          ],
        ),
      ),
      actions: [
        TextButton(
          onPressed: () => Navigator.of(context).pop(),
          child: const Text('Отмена'),
        ),
      ],
    );
  }

  Widget _row(InstrumentOut instrument) {
    final subtitle = [
      assetClassLabel(instrument.assetClass),
      if (instrument.isin != null) instrument.isin!,
      if (instrument.board != null) instrument.board!,
      instrument.currency,
    ].join(' · ');
    return ListTile(
      dense: true,
      title: Text(
        [
          if (instrument.ticker != null) instrument.ticker!,
          instrument.name,
        ].join(' · '),
      ),
      subtitle: Text(subtitle),
      onTap: () => Navigator.of(context).pop(instrument.id),
    );
  }
}