hlaskovnik-reimagined/frontend/lib/provider/quote_provider.dart

// gets all quotes from the database and returns them in a list

import 'package:file_saver/file_saver.dart';

import 'package:path_provider/path_provider.dart';
import 'package:flutter/foundation.dart'; // for kIsWeb

import 'dart:convert';
import 'dart:typed_data';
import 'package:go_router/go_router.dart';
import 'package:file_picker/file_picker.dart';
import 'package:flutter/material.dart';

import 'package:frontend/model/quote.dart';
import 'package:frontend/repository/quote_repository.dart';
import 'dart:math';
import 'dart:io';

class QuoteProvider extends ChangeNotifier {
  List<Quote> _quotes = [];
  Set<String> _authors = {};
  bool _loading = false;
  String? _error;

  List<Quote> get quotes => _quotes;
  Set<String> get authors => _authors;
  bool get loading => _loading;
  String? get error => _error;
  List<Quote> get filteredQuotes {
    final query = filterController.text.toLowerCase();

    final filtered = _quotes.where((quote) {
      switch (filterBy) {
        case 0:
          return quote.author.toLowerCase().contains(query);
        case 1:
          return quote.body.toLowerCase().contains(query);
        default:
          return true;
      }
    }).toList();

    // sort descending
    filtered.sort((a, b) => b.id.compareTo(a.id));

    return filtered;
  }

  List<MapEntry<String, int>> get sortedAuthorCounts {
    final counts = <String, int>{};

    for (var quote in filteredQuotes) {
      counts.update(
        quote.author,
        (value) => value + 1,
        ifAbsent: () => 1,
      );
    }

    final list = counts.entries.toList()
      ..sort((a, b) => b.value.compareTo(a.value)); // descending

    return list;
  }

  final QuoteRepository repo = QuoteRepository();

  int filterBy = 0; // 0 = by author, 1 = by quote
  var filterController = TextEditingController(text: '');

  void clearFilterController() {
    filterController.text = '';
  }

  late Quote randomQuote;
  bool randomQuoteDeterminator = true;

  String exportDir = "";
  String get randomQuoteText { 
    if (randomQuoteDeterminator) {
      return randomQuote.body;
    } else {
      return " – ${randomQuote.author}";
    }
  }

  void flipRandomQuote() {
    randomQuoteDeterminator = !randomQuoteDeterminator;
    notifyListeners();
  }

  void nextRandomQuote() {
    if (filteredQuotes.isEmpty) return;
    final random = Random();
    randomQuote = filteredQuotes[random.nextInt(filteredQuotes.length)];
    notifyListeners();
  }

  void filterQuotes() {
    notifyListeners();
  }

  QuoteProvider() {
    readQuotes(); // auto-load on creation
  }

  void populateAuthors() {
    _authors = {};
    for (var i = 0; i < quotes.length; i++) {
      _authors.add(quotes[i].author);
    }
  }

  void setFilterBy(int value) {
    filterBy = value;
    notifyListeners();
  }

  Future<void> readQuotes() async {
    _loading = true;
    notifyListeners();

    try {
      _quotes = await repo.readQuotes();
      populateAuthors();

      if (_quotes.isNotEmpty) {
        nextRandomQuote();
      }

    } catch (e) {
      _error = e.toString();
    }

    _loading = false;
    notifyListeners();
  }

  Future<void> createQuote(Quote quote) async {
    final newQuote = await repo.createQuote(quote);
    _quotes.add(newQuote);
    populateAuthors();
    notifyListeners();
  }

  Future<void> updateQuote(Quote quote) async {
    try {
      _loading = true;
      notifyListeners();

      final updated = await repo.updateQuote(quote);

      final index = _quotes.indexWhere((q) => q.id == quote.id);
      if (index != -1) {
        final oldAuthor = _quotes[index].author;
        final newList = List<Quote>.from(_quotes);
        newList[index] = updated;
        _quotes = newList;
        Map<String, int> authorMap = {};
        for (final q in quotes) {
          authorMap[q.author] = (authorMap[q.author] ?? 0) + 1;
        }
        if (authorMap[oldAuthor] == 1) {
          _authors.remove(oldAuthor);
        }
        _authors.add(updated.author);
      }
    } finally {      
      _loading = false;
      notifyListeners();
    }
  }

  Future<void> deleteQuote(Quote quote) async {
    await repo.deleteQuote(quote);

    _quotes.removeWhere((q) => q.id == quote.id);
    populateAuthors();
    notifyListeners();
  }

  Future<bool> exportWithSAF() async {
    try {
      final datetime = DateTime.now().toUtc().toString()
          .replaceAll(" ", "T")
          .replaceAll(":", "-")
          .replaceAll(RegExp(r"\..*"), "");
      final filename = 'hlasky_$datetime.txt';
      final content = filteredQuotes.map((q) => "${q.body} – ${q.author}").join('\n') + '\n';
      final bytes = Uint8List.fromList(utf8.encode(content));

      // Show folder picker
      final folderPath = await FilePicker.platform.getDirectoryPath();
      if (folderPath == null) return false; // user cancelled
      exportDir = folderPath;

      final file = File('$folderPath/$filename');
      await file.writeAsBytes(bytes);

      return true; // export successful
    } catch (e) {
      return false; // something went wrong
    }
  }

  Color getLeaderboardEntryBgColor(BuildContext context, int index) {
    switch (index) {
      case 0:
        return Colors.yellow.shade300; // 1st place
      case 1:
        return Colors.grey.shade300;   // 2nd place
      case 2:
        return Colors.brown.shade300;  // 3rd place
      default:
        return Theme.of(context).cardColor; // default for all other entries
    }
  }

  Color getLeaderboardEntryFgColor(BuildContext context, int index) {
    switch (index) {
      case 0:
      case 1:
      case 2:
        return Colors.black;
      default:
        return Theme.of(context).textTheme.bodyMedium!.color!;
    }
  }

  void showListPageFilteredByAuthor(BuildContext context, int index) {
    filterController.text = sortedAuthorCounts[index].key;
    filterBy = 0; // filter by author
    // navigate to the main page
    GoRouter.of(context).go('/');
    Future.microtask(() => notifyListeners());
  }

  void resetLeaderboardFilter() {
    filterController.text = '';
    filterBy = 0;
    notifyListeners();
  }
}