import 'dart:convert';

import 'package:flutter/material.dart';
import 'package:http/http.dart' as http;
import 'package:infinite_scroll_pagination/infinite_scroll_pagination.dart';
import 'package:solian/models/post.dart';
import 'package:solian/utils/service_url.dart';
import 'package:solian/widgets/indent_wrapper.dart';
import 'package:solian/widgets/posts/comment_list.dart';
import 'package:solian/widgets/posts/item.dart';
import 'package:flutter_gen/gen_l10n/app_localizations.dart';

class PostScreen extends StatefulWidget {
  final String dataset;
  final String alias;

  const PostScreen({super.key, required this.alias, required this.dataset});

  @override
  State<PostScreen> createState() => _PostScreenState();
}

class _PostScreenState extends State<PostScreen> {
  final _client = http.Client();

  final PagingController<int, Post> _commentPagingController =
      PagingController(firstPageKey: 0);

  Future<Post?> fetchPost(BuildContext context) async {
    final uri = getRequestUri(
        'interactive', '/api/p/${widget.dataset}/${widget.alias}');
    final res = await _client.get(uri);
    if (res.statusCode != 200) {
      final err = utf8.decode(res.bodyBytes);
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(content: Text("Something went wrong... $err")),
      );
      return null;
    } else {
      return Post.fromJson(jsonDecode(utf8.decode(res.bodyBytes)));
    }
  }

  @override
  Widget build(BuildContext context) {
    return IndentWrapper(
      noSafeArea: true,
      hideDrawer: true,
      title: AppLocalizations.of(context)!.post,
      child: FutureBuilder(
        future: fetchPost(context),
        builder: (context, snapshot) {
          if (snapshot.hasData && snapshot.data != null) {
            return Center(
              child: Container(
                constraints: const BoxConstraints(maxWidth: 640),
                child: CustomScrollView(
                  slivers: [
                    SliverToBoxAdapter(
                      child: PostItem(
                        item: snapshot.data!,
                        brief: false,
                        ripple: false,
                      ),
                    ),
                    SliverToBoxAdapter(
                      child: CommentListHeader(
                        related: snapshot.data!,
                        paging: _commentPagingController,
                      ),
                    ),
                    CommentList(
                      related: snapshot.data!,
                      dataset: widget.dataset,
                      paging: _commentPagingController,
                    ),
                  ],
                ),
              ),
            );
          } else {
            return const Center(
              child: CircularProgressIndicator(),
            );
          }
        },
      ),
    );
  }

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