import 'dart:math';

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

import '../../../localization/app_localizations.dart';
import '../../../recipes/models/recipe.dart';
import '../../../recipes/recipe_list_provider.dart';
import '../../../settings/settings_controller.dart';
import '../../day.dart';
import '../../models/plan_entry.dart';
import '../../plan_repository.dart';
import '../../week_fill.dart';
import '../../week_plan_provider.dart';
import 'plan_slot_sheet.dart';

/// "Neu würfeln": another Recipe of the same Course, by the rules of "Woche füllen".
Future<void> rerollEntry(BuildContext context, PlanEntry entry, Recipe current) async {
  final l10n = AppLocalizations.of(context);
  final messenger = ScaffoldMessenger.of(context);
  final week = context.read<WeekPlanProvider>();
  final recipes = context.read<RecipeListProvider>().allRecipes;
  final plan = context.read<PlanRepository>();
  final weekStart = weekStartOf(entry.day, context.read<SettingsController>().weekStart);
  final replacement = pickReplacement(
    candidates: [
      for (final r in recipes)
        if (current.courseId == null || r.courseId == current.courseId) r,
    ],
    inWeek: week.recipeIdsBetween(weekStart, addDays(weekStart, 6)),
    recent: week.recipeIdsBetween(addDays(weekStart, -7 * recentWeeks), addDays(weekStart, -1)),
    random: Random(),
  );
  if (replacement == null) {
    messenger.showSnackBar(SnackBar(content: Text(l10n.noOtherRecipe)));
    return;
  }
  await plan.replaceRecipe(entry.id, replacement.id);
}

/// "Verschieben …": asks for a day and Meal.
Future<void> moveEntryWithPicker(BuildContext context, PlanEntry entry) async {
  final l10n = AppLocalizations.of(context);
  final plan = context.read<PlanRepository>();
  final slot = await showPlanSlotSheet(
    context,
    action: l10n.moveEntryTitle,
    initialDay: entry.day,
    initialMealId: entry.mealId,
  );
  if (slot == null) return;
  final (day, mealId) = slot;
  await plan.moveEntry(entry.id, day, mealId);
}

/// Removes the entry, with "Rückgängig" in the SnackBar.
Future<void> removeEntryWithUndo(BuildContext context, PlanEntry entry, String name) async {
  final l10n = AppLocalizations.of(context);
  final messenger = ScaffoldMessenger.of(context);
  final plan = context.read<PlanRepository>();
  await plan.removeEntry(entry.id);
  messenger
    ..hideCurrentSnackBar()
    ..showSnackBar(
      SnackBar(
        content: Text(l10n.entryRemoved(name)),
        duration: const Duration(milliseconds: 1500),
        action: SnackBarAction(
          label: l10n.undo,
          onPressed: () => plan.addEntry(entry.day, entry.mealId, recipeId: entry.recipeId, note: entry.note),
        ),
      ),
    );
}

/// "Bearbeiten" on a note: a small dialog with its text.
Future<void> editNote(BuildContext context, PlanEntry entry) async {
  final plan = context.read<PlanRepository>();
  final text = await showDialog<String>(
    context: context,
    builder: (_) => _NoteDialog(note: entry.note ?? ''),
  );
  if (text != null && text.isNotEmpty) await plan.updateNote(entry.id, text);
}

class _NoteDialog extends StatefulWidget {
  const _NoteDialog({required this.note});

  final String note;

  @override
  State<_NoteDialog> createState() => _NoteDialogState();
}

class _NoteDialogState extends State<_NoteDialog> {
  late final _text = TextEditingController(text: widget.note);

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

  void _save() => Navigator.pop(context, _text.text.trim());

  @override
  Widget build(BuildContext context) {
    final l10n = AppLocalizations.of(context);
    return AlertDialog(
      title: Text(l10n.editNoteTitle),
      content: TextField(
        controller: _text,
        autofocus: true,
        textCapitalization: TextCapitalization.sentences,
        onSubmitted: (_) => _save(),
      ),
      actions: [
        TextButton(onPressed: () => Navigator.pop(context), child: Text(l10n.cancel)),
        FilledButton(onPressed: _save, child: Text(l10n.save)),
      ],
    );
  }
}