import 'dart:typed_data';

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

import '../data/variety_repository.dart';
import '../i18n/strings.g.dart';
import '../services/ocr/label_text_extractor.dart';
import 'photo_pick.dart';

/// Rapid "capture now, catalogue later": shoot/pick a burst of photos and turn
/// each into a draft variety. Returns how many were captured.
Future<int> captureDraftBurst(
  BuildContext context,
  VarietyRepository repository,
) async {
  final photos = await pickPhotos(context);
  for (final bytes in photos) {
    await repository.addDraftVariety(bytes);
  }
  return photos.length;
}

/// The "to catalogue" tray: lists photo-first drafts (live from the DB); tapping
/// one prompts for a name and promotes it into the inventory.
Future<void> showTriageSheet(
  BuildContext context,
  VarietyRepository repository,
) {
  return showModalBottomSheet<void>(
    context: context,
    isScrollControlled: true,
    builder: (_) => _TriageSheet(repository: repository),
  );
}

class _TriageSheet extends StatelessWidget {
  const _TriageSheet({required this.repository});

  final VarietyRepository repository;

  @override
  Widget build(BuildContext context) {
    final t = context.t;
    return StreamBuilder<List<VarietyListItem>>(
      stream: repository.watchDrafts(),
      builder: (context, snapshot) {
        final drafts = snapshot.data ?? const <VarietyListItem>[];
        return Padding(
          padding: EdgeInsets.only(
            left: 16,
            right: 16,
            top: 16,
            bottom: MediaQuery.of(context).viewInsets.bottom + 16,
          ),
          child: Column(
            mainAxisSize: MainAxisSize.min,
            crossAxisAlignment: CrossAxisAlignment.stretch,
            children: [
              Text(
                t.draft.triageTitle,
                style: Theme.of(context).textTheme.titleLarge,
              ),
              const SizedBox(height: 12),
              if (drafts.isEmpty)
                Padding(
                  padding: const EdgeInsets.symmetric(vertical: 24),
                  child: Text(
                    t.inventory.empty,
                    textAlign: TextAlign.center,
                    style: Theme.of(context).textTheme.bodyMedium,
                  ),
                )
              else
                Flexible(
                  child: ListView.builder(
                    shrinkWrap: true,
                    itemCount: drafts.length,
                    itemBuilder: (context, i) => _DraftTile(
                      draft: drafts[i],
                      repository: repository,
                    ),
                  ),
                ),
            ],
          ),
        );
      },
    );
  }
}

class _DraftTile extends StatelessWidget {
  const _DraftTile({required this.draft, required this.repository});

  final VarietyListItem draft;
  final VarietyRepository repository;

  @override
  Widget build(BuildContext context) {
    final t = context.t;
    final photo = draft.photo;
    return ListTile(
      key: Key('draft.tile.${draft.id}'),
      leading: photo == null
          ? const Icon(Icons.image_outlined)
          : ClipRRect(
              borderRadius: BorderRadius.circular(8),
              child: Image.memory(
                photo,
                width: 48,
                height: 48,
                fit: BoxFit.cover,
              ),
            ),
      title: Text(t.draft.untitled),
      trailing: IconButton(
        icon: const Icon(Icons.delete_outline),
        tooltip: t.draft.discard,
        onPressed: () => repository.softDeleteVariety(draft.id),
      ),
      onTap: () async {
        final name = await showDialog<String>(
          context: context,
          builder: (_) => NameDraftDialog(photo: photo),
        );
        if (name != null && name.trim().isNotEmpty) {
          await repository.nameDraft(draft.id, name.trim());
        }
      },
    );
  }
}

/// Prompts for a draft's name, showing its photo. Where an on-device OCR engine
/// exists, a "Suggest name from photo" button pre-fills the field (always
/// editable, never auto-confirmed).
class NameDraftDialog extends StatefulWidget {
  const NameDraftDialog({required this.photo, this.extractor, super.key});

  final Uint8List? photo;

  /// Injectable for tests; otherwise resolved from the service locator (or a
  /// no-op when none is registered).
  final LabelTextExtractor? extractor;

  @override
  State<NameDraftDialog> createState() => _NameDraftDialogState();
}

class _NameDraftDialogState extends State<NameDraftDialog> {
  final _controller = TextEditingController();
  bool _suggesting = false;

  LabelTextExtractor get _extractor =>
      widget.extractor ??
      (GetIt.instance.isRegistered<LabelTextExtractor>()
          ? GetIt.instance<LabelTextExtractor>()
          : const NoOpLabelTextExtractor());

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

  Future<void> _suggest() async {
    final photo = widget.photo;
    if (photo == null) return;
    setState(() => _suggesting = true);
    final suggestion = await _extractor.suggestLabel(photo);
    if (!mounted) return;
    setState(() {
      _suggesting = false;
      if (suggestion != null && suggestion.trim().isNotEmpty) {
        _controller.text = suggestion.trim();
      }
    });
  }

  @override
  Widget build(BuildContext context) {
    final t = context.t;
    final canSuggest = widget.photo != null && _extractor.isSupported;
    return AlertDialog(
      title: Text(t.draft.nameField),
      content: Column(
        mainAxisSize: MainAxisSize.min,
        crossAxisAlignment: CrossAxisAlignment.stretch,
        children: [
          if (widget.photo != null)
            ClipRRect(
              borderRadius: BorderRadius.circular(8),
              child: Image.memory(
                widget.photo!,
                height: 140,
                fit: BoxFit.cover,
              ),
            ),
          const SizedBox(height: 12),
          TextField(
            key: const Key('draft.nameField'),
            controller: _controller,
            autofocus: true,
            textCapitalization: TextCapitalization.sentences,
            decoration: InputDecoration(
              hintText: t.draft.nameHint,
              border: const OutlineInputBorder(),
            ),
            onSubmitted: (value) => Navigator.of(context).pop(value),
          ),
          if (canSuggest) ...[
            const SizedBox(height: 8),
            Align(
              alignment: AlignmentDirectional.centerStart,
              child: TextButton.icon(
                key: const Key('draft.suggestFromPhoto'),
                onPressed: _suggesting ? null : _suggest,
                icon: _suggesting
                    ? const SizedBox(
                        width: 16,
                        height: 16,
                        child: CircularProgressIndicator(strokeWidth: 2),
                      )
                    : const Icon(Icons.auto_fix_high_outlined),
                label: Text(t.draft.suggestFromPhoto),
              ),
            ),
          ],
        ],
      ),
      actions: [
        TextButton(
          onPressed: () => Navigator.of(context).pop(),
          child: Text(t.common.cancel),
        ),
        FilledButton(
          key: const Key('draft.nameSave'),
          onPressed: () => Navigator.of(context).pop(_controller.text),
          child: Text(t.common.save),
        ),
      ],
    );
  }
}