import 'dart:io';
import 'dart:math';

import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:flutter_bloc/flutter_bloc.dart';
import 'package:pmu_labworks/components/extensions/context_x.dart';
import 'package:pmu_labworks/components/utils/debounce.dart';
import 'package:pmu_labworks/domain/models/comment.dart';
import 'package:pmu_labworks/domain/models/user.dart';
import 'package:pmu_labworks/view/common/svg_objects.dart';
import 'package:pmu_labworks/view/details_page/details_page.dart';
import 'package:pmu_labworks/view/home_page/bloc/bloc.dart';
import 'package:pmu_labworks/view/home_page/bloc/events.dart';
import 'package:pmu_labworks/view/home_page/bloc/state.dart';
import 'package:pmu_labworks/view/reaction_bloc/reaction_bloc.dart';
import 'package:pmu_labworks/view/reaction_bloc/reaction_event.dart';
import 'package:pmu_labworks/view/reaction_bloc/reaction_state.dart';
import 'package:pmu_labworks/view/locale_bloc/locale_bloc.dart';
import 'package:pmu_labworks/view/locale_bloc/locale_events.dart';
import 'package:pmu_labworks/view/locale_bloc/locale_state.dart';

part 'comment.dart';

class HomePage extends StatefulWidget {
  const HomePage({super.key, required this.title});

  final String title;

  @override
  State<HomePage> createState() => _HomePageState();
}

class _HomePageState extends State<HomePage> {
  Color _color = Colors.transparent;

  @override
  void initState() {
    super.initState();
    _color = _generateColor();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        backgroundColor: _color,
        title: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Text(widget.title,
                style: const TextStyle(
                  fontSize: 20,
                  fontWeight: FontWeight.bold,
                )),
            Text(
              context.locale.credits + ' Factorino',
              style: TextStyle(
                fontSize: 12,
                fontStyle: FontStyle.italic,
              ),
            ),
          ],
        ),
      ),
      body: const _Body(),
    );
  }

  Color _generateColor() {
    final Random random = Random();
    final int red = (random.nextInt(106) + 150);
    final int green = (random.nextInt(106) + 150);
    final int blue = (random.nextInt(106) + 150);

    return Color.fromARGB(255, red, green, blue);
  }
}

class _Body extends StatefulWidget {
  const _Body();

  @override
  State<_Body> createState() => _BodyState();
}

class _BodyState extends State<_Body> {
  final searchController = TextEditingController();
  final scrollController = ScrollController();

  @override
  void initState() {
    SvgObjects.init();

    WidgetsBinding.instance.addPostFrameCallback((_) {
      context.read<HomeBloc>().add(const HomeLoadDataEvent());
      context.read<ReactionBloc>().add(const LoadReactionsEvent());
    });

    scrollController.addListener(_onNextPageListener);

    super.initState();
  }

  @override
  void dispose() {
    searchController.dispose();
    scrollController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return Padding(
      padding: EdgeInsets.only(top: MediaQuery.of(context).padding.top),
      child: Column(
        children: [
          Row(
            children: [
              Expanded(
                flex: 4,
                child: Padding(
                  padding: const EdgeInsets.all(12),
                  child: CupertinoSearchTextField(
                    controller: searchController,
                    placeholder: context.locale.search,
                    onChanged: (search) {
                      Debounce.run(
                          () => context.read<HomeBloc>().add(HomeLoadDataEvent(search: search)));
                    },
                  ),
                ),
              ),
              GestureDetector(
                onTap: () => context.read<LocaleBloc>().add(const ChangeLocaleEvent()),
                child: SizedBox.square(
                  dimension: 50,
                  child: Padding(
                    padding: const EdgeInsets.only(right: 12),
                    child: BlocBuilder<LocaleBloc, LocaleState>(
                      builder: (context, state) {
                        return state.currentLocale.languageCode == 'ru'
                            ? const SvgRu()
                            : const SvgUk();
                      },
                    ),
                  ),
                ),
              ),
            ],
          ),
          BlocBuilder<HomeBloc, HomeState>(
            builder: (context, state) => state.error != null
                ? Text(
                    state.error ?? '',
                    style: Theme.of(context).textTheme.headlineSmall?.copyWith(color: Colors.red),
                  )
                : state.isLoading
                    ? const CircularProgressIndicator()
                    : BlocBuilder<ReactionBloc, ReactionState>(
                        builder: (context, reactionState) {
                          return Expanded(
                            child: RefreshIndicator(
                              onRefresh: _onRefresh,
                              child: ListView.builder(
                                controller: scrollController,
                                padding: EdgeInsets.zero,
                                itemCount: state.data?.data?.length ?? 0,
                                itemBuilder: (context, index) {
                                  final data = state.data?.data?[index];
                                  return data != null
                                      ? _Comment.fromData(
                                          data,
                                          onLike: _onLike,
                                          onDislike: _onDislike,
                                          isLiked:
                                              reactionState.likedIds?.contains(data.id) == true,
                                          isDisliked:
                                              reactionState.dislikedIds?.contains(data.id) == true,
                                          onTap: () => _navToDetails(context, data),
                                        )
                                      : const SizedBox.shrink();
                                },
                              ),
                            ),
                          );
                        },
                      ),
          ),
          BlocBuilder<HomeBloc, HomeState>(
            builder: (context, state) => state.isPaginationLoading
                ? const CircularProgressIndicator()
                : const SizedBox.shrink(),
          ),
        ],
      ),
    );
  }

  Future<void> _onRefresh() {
    context.read<HomeBloc>().add(HomeLoadDataEvent(search: searchController.text));
    return Future.value(null);
  }

  void _onLike(String? id, String nickname, bool isLiked, bool isDisliked) {
    if (id != null) {
      if (isDisliked) {
        isDisliked = false;
      }
      context.read<ReactionBloc>().add(ChangeLikeEvent(id));
      _showSnackBar(context, nickname, !isLiked, isDisliked);
    }
  }

  void _onDislike(String? id, String nickname, bool isLiked, bool isDisliked) {
    if (id != null) {
      if (isLiked) {
        isLiked = false;
      }
      context.read<ReactionBloc>().add(ChangeDislikeEvent(id));
      _showSnackBar(context, nickname, isLiked, !isDisliked);
    }
  }

  void _navToDetails(BuildContext context, CommentData data) {
    Navigator.push(
      context,
      CupertinoPageRoute(builder: (context) => DetailsPage(data)),
    );
  }

  void _showSnackBar(BuildContext context, String nickname, bool isLiked, bool isDisliked) {
    WidgetsBinding.instance.addPostFrameCallback((_) {
      final String action;

      if (isLiked && !isDisliked) {
        action = context.locale.liked;
      } else if (!isLiked && isDisliked) {
        action = context.locale.disliked;
      } else {
        action = context.locale.neutralized; // Состояние без лайков/дизлайков
      }
      print('$isLiked $isDisliked = $action');

      ScaffoldMessenger.of(context).showSnackBar(SnackBar(
        content: Text(
          context.locale.comment(nickname) + ' ' + action,
          style: Theme.of(context).textTheme.bodyLarge,
        ),
        backgroundColor: Colors.white70,
        duration: const Duration(seconds: 1),
      ));
    });
  }

  void _onNextPageListener() {
    if (scrollController.offset >= scrollController.position.maxScrollExtent) {
      // preventing multiple pagination request on multiple swipes
      final bloc = context.read<HomeBloc>();
      if (!bloc.state.isPaginationLoading) {
        bloc.add(HomeLoadDataEvent(
          search: searchController.text,
          nextPage: bloc.state.data?.nextPage,
        ));
      }
    }
  }
}