import 'dart:async';

import 'package:flutter_riverpod/flutter_riverpod.dart';
import '../../../core/constants.dart';
import '../../../core/database/app_database.dart';
import '../data/search_repository.dart';

class SearchState {
  final String query;
  final List<SearchResult> results;
  final List<SearchHistoryData> recentSearches;
  final bool isLoading;
  final String? error;

  const SearchState({
    this.query = '',
    this.results = const [],
    this.recentSearches = const [],
    this.isLoading = false,
    this.error,
  });

  SearchState copyWith({
    String? query,
    List<SearchResult>? results,
    List<SearchHistoryData>? recentSearches,
    bool? isLoading,
    String? error,
    bool clearError = false,
  }) {
    return SearchState(
      query: query ?? this.query,
      results: results ?? this.results,
      recentSearches: recentSearches ?? this.recentSearches,
      isLoading: isLoading ?? this.isLoading,
      error: clearError ? null : (error ?? this.error),
    );
  }
}

class SearchNotifier extends Notifier<SearchState> {
  late SearchRepository _repository;
  Timer? _debounce;

  @override
  SearchState build() {
    _repository = ref.watch(searchRepositoryProvider);
    ref.onDispose(() => _debounce?.cancel());
    Future.microtask(_loadHistory);
    return const SearchState();
  }

  Future<void> _loadHistory() async {
    final history = await _repository.getRecentSearches();
    state = state.copyWith(recentSearches: history);
  }

  void updateQuery(String query) {
    state = state.copyWith(query: query, clearError: true);
    _debounce?.cancel();

    if (query.trim().isEmpty) {
      state = state.copyWith(results: [], isLoading: false);
      return;
    }

    state = state.copyWith(isLoading: true);
    _debounce = Timer(
      const Duration(milliseconds: AppConstants.searchDebounceMs),
      () => _performSearch(query),
    );
  }

  Future<void> _performSearch(String query) async {
    try {
      final results = await _repository.search(query);
      if (state.query == query) {
        state = state.copyWith(results: results, isLoading: false);
      }
    } catch (e) {
      state = state.copyWith(
        isLoading: false,
        error: 'Search failed. Please try again.',
      );
    }
  }

  Future<void> selectResult(SearchResult result) async {
    await _repository.saveToHistory(
      result.name,
      lat: result.latitude,
      lon: result.longitude,
    );
    await _loadHistory();
  }

  Future<void> deleteHistoryEntry(int id) async {
    await _repository.deleteHistoryEntry(id);
    await _loadHistory();
  }

  Future<void> clearHistory() async {
    await _repository.clearHistory();
    await _loadHistory();
  }
}

final searchProvider =
    NotifierProvider.autoDispose<SearchNotifier, SearchState>(
  SearchNotifier.new,
);