import 'dart:convert';
import 'dart:ui';

import 'package:shared_preferences/shared_preferences.dart';

class PreferencesService {
  static const _keyColor1 = 'color1';
  static const _keyColor2 = 'color2';
  static const _keyDiaryEntries = 'diaryEntries';

  // Load color preferences
  Future<ColorPreference> loadColors() async {
    final SharedPreferences prefs = await SharedPreferences.getInstance();
    final String? color1 = prefs.getString(_keyColor1);
    final String? color2 = prefs.getString(_keyColor2);

    return ColorPreference(
      color1: color1 != null ? Color(int.parse(color1)) : null,
      color2: color2 != null ? Color(int.parse(color2)) : null,
    );
  }

  // Save color preferences
  Future<void> saveColors(Color color1, Color color2) async {
    final SharedPreferences prefs = await SharedPreferences.getInstance();
    await prefs.setString(_keyColor1, color1.value.toString());
    await prefs.setString(_keyColor2, color2.value.toString());
  }

  // Get the diary entry for the current date
  Future<DiaryEntry?> getDiaryEntryByCurrentDate() async {
    final SharedPreferences prefs = await SharedPreferences.getInstance();
    final String diaryEntriesJson = prefs.getString(_keyDiaryEntries) ?? '{}';
    final Map<String, dynamic> diaryEntriesMap = json.decode(diaryEntriesJson);

    String todayKey = DateTime.now().toIso8601String().split('T')[0];

    if (diaryEntriesMap.containsKey(todayKey)) {
      final Map<String, dynamic> entryData = diaryEntriesMap[todayKey];
      final List<String> texts = List<String>.from(entryData['texts']);
      return DiaryEntry(
        date: DateTime.parse(todayKey),
        percentValue: entryData['percentValue'],
        texts: texts,
      );
    }
    return null;
  }

  // Get the diary entry by a given date
  Future<DiaryEntry?> getDiaryEntryByDate(DateTime date) async {
    final SharedPreferences prefs = await SharedPreferences.getInstance();
    final String diaryEntriesJson = prefs.getString(_keyDiaryEntries) ?? '{}';
    final Map<String, dynamic> diaryEntriesMap = json.decode(diaryEntriesJson);

    String dateKey = date.toIso8601String().split('T')[0];

    if (diaryEntriesMap.containsKey(dateKey)) {
      final Map<String, dynamic> entryData = diaryEntriesMap[dateKey];
      final List<String> texts = List<String>.from(entryData['texts']);
      return DiaryEntry(
        date: DateTime.parse(dateKey),
        percentValue: entryData['percentValue'],
        texts: texts,
      );
    }
    return null;
  }

  // Save a diary entry
  Future<void> saveDiaryEntry(DiaryEntry entry) async {
    final SharedPreferences prefs = await SharedPreferences.getInstance();
    final Map<String, dynamic> diaryEntriesMap =
        json.decode(prefs.getString(_keyDiaryEntries) ?? '{}');

    // Use the date as the ID for the diary entry
    final String dateKey = entry.date.toIso8601String().split('T')[0];

    // If the entry is new or the date is older than two days, add or update the text
    if (!diaryEntriesMap.containsKey(dateKey) ||
        DateTime.now().difference(entry.date).inDays > 2) {
      final List<String> texts = diaryEntriesMap[dateKey] != null
          ? List<String>.from(diaryEntriesMap[dateKey]['texts'])
          : [];
      texts.addAll(entry.texts);
      diaryEntriesMap[dateKey] = {
        'percentValue': entry.percentValue,
        'texts': texts,
      };
    } else {
      // For an existing entry less than two days old, update the percent value and overwrite the text
      diaryEntriesMap[dateKey] = {
        'percentValue': entry.percentValue,
        'texts': entry.texts,
      };
    }

    await prefs.setString(_keyDiaryEntries, json.encode(diaryEntriesMap));
  }

  // Load diary entries
  Future<List<DiaryEntry>> loadDiaryEntries() async {
    final SharedPreferences prefs = await SharedPreferences.getInstance();
    final String diaryEntriesJson = prefs.getString(_keyDiaryEntries) ?? '{}';
    final Map<String, dynamic> diaryEntriesMap = json.decode(diaryEntriesJson);

    return diaryEntriesMap.entries.map((entry) {
      final List<String> texts = List<String>.from(entry.value['texts']);
      return DiaryEntry(
        date: DateTime.parse(entry.key),
        percentValue: entry.value['percentValue'],
        texts: texts,
      );
    }).toList();
  }
}

// Helper class to store color preferences
class ColorPreference {
  final Color? color1;
  final Color? color2;

  ColorPreference({this.color1, this.color2});
}

// Diary entry data model
class DiaryEntry {
  final DateTime date;
  final int percentValue;
  final List<String> texts;

  DiaryEntry({
    required this.date,
    required this.percentValue,
    required this.texts,
  });
}