import 'package:commons_core/commons_core.dart';
import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';

import '../data/species_repository.dart';
import '../data/variety_repository.dart';
import '../i18n/strings.g.dart';
import '../state/variety_detail_cubit.dart';
import 'quantity_kind_l10n.dart';

/// Read + edit view of a single variety: its photo, category, notes, other
/// names and lots. Edits go through [VarietyDetailCubit]; the view is reactive.
class VarietyDetailScreen extends StatelessWidget {
  const VarietyDetailScreen({super.key});

  @override
  Widget build(BuildContext context) {
    return BlocConsumer<VarietyDetailCubit, VarietyDetailState>(
      listenWhen: (prev, curr) => !prev.deleted && curr.deleted,
      listener: (context, state) => Navigator.of(context).maybePop(),
      builder: (context, state) {
        if (state.loading) {
          return const Scaffold(
            body: Center(child: CircularProgressIndicator()),
          );
        }
        final detail = state.detail;
        if (detail == null) {
          return Scaffold(
            appBar: AppBar(),
            body: Center(child: Text(context.t.detail.notFound)),
          );
        }
        return _DetailView(detail: detail);
      },
    );
  }
}

class _DetailView extends StatelessWidget {
  const _DetailView({required this.detail});

  final VarietyDetail detail;

  @override
  Widget build(BuildContext context) {
    final t = context.t;
    final cubit = context.read<VarietyDetailCubit>();
    return Scaffold(
      appBar: AppBar(
        title: Text(detail.label),
        actions: [
          IconButton(
            key: const Key('detail.edit'),
            icon: const Icon(Icons.edit_outlined),
            tooltip: t.common.edit,
            onPressed: () => _showEditSheet(
              context,
              cubit,
              detail,
              context.read<SpeciesRepository>(),
            ),
          ),
          IconButton(
            key: const Key('detail.delete'),
            icon: const Icon(Icons.delete_outline),
            tooltip: t.common.delete,
            onPressed: () => _confirmDelete(context, cubit),
          ),
        ],
      ),
      body: ListView(
        padding: const EdgeInsets.all(16),
        children: [
          if (detail.scientificName != null) ...[
            Text(
              detail.scientificName!,
              style: Theme.of(context).textTheme.titleMedium?.copyWith(
                fontStyle: FontStyle.italic,
                color: Theme.of(context).colorScheme.onSurfaceVariant,
              ),
            ),
            const SizedBox(height: 12),
          ],
          if (detail.photo != null)
            ClipRRect(
              borderRadius: BorderRadius.circular(12),
              child: Image.memory(
                detail.photo!,
                height: 200,
                width: double.infinity,
                fit: BoxFit.cover,
              ),
            ),
          if (detail.category != null) ...[
            const SizedBox(height: 12),
            Align(
              alignment: Alignment.centerLeft,
              child: Chip(label: Text(detail.category!)),
            ),
          ],
          if (detail.vernacularNames.isNotEmpty) ...[
            const SizedBox(height: 16),
            _SectionTitle(t.detail.names),
            Wrap(
              spacing: 8,
              children: [
                for (final name in detail.vernacularNames)
                  Chip(label: Text(name)),
              ],
            ),
          ],
          if (detail.notes != null && detail.notes!.trim().isNotEmpty) ...[
            const SizedBox(height: 16),
            _SectionTitle(t.detail.notes),
            Text(detail.notes!),
          ],
          const SizedBox(height: 16),
          Row(
            mainAxisAlignment: MainAxisAlignment.spaceBetween,
            children: [
              _SectionTitle(t.detail.lots),
              TextButton.icon(
                key: const Key('detail.addLot'),
                onPressed: () => _showAddLotSheet(context, cubit),
                icon: const Icon(Icons.add),
                label: Text(t.detail.addLot),
              ),
            ],
          ),
          if (detail.lots.isEmpty)
            Text(t.detail.noLots)
          else
            for (final lot in detail.lots)
              ListTile(
                contentPadding: EdgeInsets.zero,
                leading: const Icon(Icons.inventory_2_outlined),
                title: Text(_lotSubtitle(t, lot)),
                subtitle: lot.storageLocation == null
                    ? null
                    : Text(lot.storageLocation!),
              ),
        ],
      ),
    );
  }
}

String _lotSubtitle(Translations t, VarietyLot lot) {
  final parts = <String>[
    if (lot.harvestYear != null)
      t.detail.year(year: lot.harvestYear!)
    else
      t.detail.noYear,
    if (lot.quantity != null) _quantityLabel(t, lot.quantity!),
  ];
  return parts.join(' · ');
}

String _quantityLabel(Translations t, Quantity q) {
  final kind = quantityKindLabel(t, q.kind);
  if (q.precise != null) return '${_trimDouble(q.precise!)} $kind';
  return kind;
}

String _trimDouble(double v) =>
    v == v.roundToDouble() ? v.toStringAsFixed(0) : v.toString();

Future<void> _confirmDelete(
  BuildContext context,
  VarietyDetailCubit cubit,
) async {
  final t = context.t;
  final confirmed = await showDialog<bool>(
    context: context,
    builder: (dialogContext) => AlertDialog(
      content: Text(t.detail.deleteConfirm),
      actions: [
        TextButton(
          onPressed: () => Navigator.of(dialogContext).pop(false),
          child: Text(t.common.cancel),
        ),
        FilledButton(
          key: const Key('detail.deleteConfirm'),
          onPressed: () => Navigator.of(dialogContext).pop(true),
          child: Text(t.common.delete),
        ),
      ],
    ),
  );
  if (confirmed ?? false) await cubit.deleteVariety();
}

Future<void> _showEditSheet(
  BuildContext context,
  VarietyDetailCubit cubit,
  VarietyDetail detail,
  SpeciesRepository species,
) {
  return showModalBottomSheet<void>(
    context: context,
    isScrollControlled: true,
    builder: (_) =>
        _EditVarietySheet(cubit: cubit, detail: detail, species: species),
  );
}

/// The edit sheet, stateful so it can search the species catalog live and link
/// the picked species on save.
class _EditVarietySheet extends StatefulWidget {
  const _EditVarietySheet({
    required this.cubit,
    required this.detail,
    required this.species,
  });

  final VarietyDetailCubit cubit;
  final VarietyDetail detail;
  final SpeciesRepository species;

  @override
  State<_EditVarietySheet> createState() => _EditVarietySheetState();
}

class _EditVarietySheetState extends State<_EditVarietySheet> {
  late final TextEditingController _name = TextEditingController(
    text: widget.detail.label,
  );
  late final TextEditingController _category = TextEditingController(
    text: widget.detail.category ?? '',
  );
  late final TextEditingController _notes = TextEditingController(
    text: widget.detail.notes ?? '',
  );
  late final TextEditingController _speciesField = TextEditingController(
    text: widget.detail.scientificName ?? '',
  );

  List<SpeciesMatch> _suggestions = const [];
  String? _pickedSpeciesId;

  @override
  void dispose() {
    _name.dispose();
    _category.dispose();
    _notes.dispose();
    _speciesField.dispose();
    super.dispose();
  }

  Future<void> _onSpeciesQuery(String query) async {
    final lang = Localizations.localeOf(context).languageCode;
    final results = await widget.species.search(query, languageCode: lang);
    if (mounted) setState(() => _suggestions = results);
  }

  void _pick(SpeciesMatch match) {
    setState(() {
      _pickedSpeciesId = match.id;
      _speciesField.text = match.displayLabel;
      _suggestions = const [];
    });
  }

  void _save() {
    final name = _name.text.trim();
    widget.cubit.updateFields(
      label: name.isEmpty ? null : name,
      category: _nullIfBlank(_category.text),
      notes: _nullIfBlank(_notes.text),
    );
    if (_pickedSpeciesId != null) {
      widget.cubit.linkSpecies(_pickedSpeciesId!);
    }
    Navigator.of(context).pop();
  }

  @override
  Widget build(BuildContext context) {
    final t = context.t;
    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.editVariety.title,
            style: Theme.of(context).textTheme.titleLarge,
          ),
          const SizedBox(height: 12),
          TextField(
            key: const Key('editVariety.name'),
            controller: _name,
            decoration: InputDecoration(
              labelText: t.editVariety.name,
              border: const OutlineInputBorder(),
            ),
          ),
          const SizedBox(height: 12),
          TextField(
            key: const Key('editVariety.species'),
            controller: _speciesField,
            decoration: InputDecoration(
              labelText: t.editVariety.species,
              hintText: t.editVariety.speciesHint,
              prefixIcon: const Icon(Icons.eco_outlined),
              border: const OutlineInputBorder(),
            ),
            onChanged: _onSpeciesQuery,
          ),
          for (final match in _suggestions)
            ListTile(
              dense: true,
              key: Key('species.option.${match.id}'),
              title: Text(match.displayLabel),
              subtitle: match.family == null ? null : Text(match.family!),
              onTap: () => _pick(match),
            ),
          const SizedBox(height: 12),
          TextField(
            controller: _category,
            decoration: InputDecoration(
              labelText: t.editVariety.category,
              border: const OutlineInputBorder(),
            ),
          ),
          const SizedBox(height: 12),
          TextField(
            controller: _notes,
            minLines: 2,
            maxLines: 5,
            decoration: InputDecoration(
              labelText: t.editVariety.notes,
              border: const OutlineInputBorder(),
            ),
          ),
          const SizedBox(height: 16),
          Row(
            children: [
              TextButton(
                onPressed: () => Navigator.of(context).pop(),
                child: Text(t.common.cancel),
              ),
              const Spacer(),
              FilledButton(
                key: const Key('editVariety.save'),
                onPressed: _save,
                child: Text(t.common.save),
              ),
            ],
          ),
        ],
      ),
    );
  }
}

Future<void> _showAddLotSheet(BuildContext context, VarietyDetailCubit cubit) {
  final t = context.t;
  final yearController = TextEditingController();
  QuantityKind? selectedKind;
  return showModalBottomSheet<void>(
    context: context,
    isScrollControlled: true,
    builder: (sheetContext) => StatefulBuilder(
      builder: (sheetContext, setState) => Padding(
        padding: EdgeInsets.only(
          left: 16,
          right: 16,
          top: 16,
          bottom: MediaQuery.of(sheetContext).viewInsets.bottom + 16,
        ),
        child: Column(
          mainAxisSize: MainAxisSize.min,
          crossAxisAlignment: CrossAxisAlignment.stretch,
          children: [
            Text(
              t.addLot.title,
              style: Theme.of(sheetContext).textTheme.titleLarge,
            ),
            const SizedBox(height: 12),
            TextField(
              key: const Key('addLot.year'),
              controller: yearController,
              keyboardType: TextInputType.number,
              decoration: InputDecoration(
                labelText: t.addLot.year,
                border: const OutlineInputBorder(),
              ),
            ),
            const SizedBox(height: 16),
            Text(
              t.addLot.quantity,
              style: Theme.of(sheetContext).textTheme.labelLarge,
            ),
            const SizedBox(height: 8),
            Wrap(
              spacing: 8,
              children: [
                for (final kind in _addLotKinds)
                  ChoiceChip(
                    label: Text(quantityKindLabel(t, kind)),
                    selected: selectedKind == kind,
                    onSelected: (_) => setState(() => selectedKind = kind),
                  ),
              ],
            ),
            const SizedBox(height: 16),
            Row(
              children: [
                TextButton(
                  onPressed: () => Navigator.of(sheetContext).pop(),
                  child: Text(t.common.cancel),
                ),
                const Spacer(),
                FilledButton(
                  key: const Key('addLot.save'),
                  onPressed: () {
                    cubit.addLot(
                      year: int.tryParse(yearController.text.trim()),
                      quantity: selectedKind == null
                          ? null
                          : Quantity(kind: selectedKind!),
                    );
                    Navigator.of(sheetContext).pop();
                  },
                  child: Text(t.common.save),
                ),
              ],
            ),
          ],
        ),
      ),
    ),
  );
}

const _addLotKinds = <QuantityKind>[
  QuantityKind.aFew,
  QuantityKind.handful,
  QuantityKind.packet,
  QuantityKind.pod,
  QuantityKind.cob,
  QuantityKind.grams,
];

String? _nullIfBlank(String value) {
  final trimmed = value.trim();
  return trimmed.isEmpty ? null : trimmed;
}

class _SectionTitle extends StatelessWidget {
  const _SectionTitle(this.text);

  final String text;

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: const EdgeInsets.only(bottom: 8),
      child: Text(
        text,
        style: Theme.of(context).textTheme.titleMedium?.copyWith(
          color: Theme.of(context).colorScheme.primary,
        ),
      ),
    );
  }
}