import 'dart:convert';

import 'package:flutter/material.dart';
import 'package:infinite_scroll_pagination/infinite_scroll_pagination.dart';
import 'package:solaragent/models/feed.dart';
import 'package:solaragent/models/pagination.dart';
import 'package:http/http.dart' as http;
import 'package:solaragent/widgets/feed.dart';

class ExploreScreen extends StatefulWidget {
  const ExploreScreen({super.key});

  @override
  State<ExploreScreen> createState() => _ExploreScreenState();
}

class _ExploreScreenState extends State<ExploreScreen> {
  static const pageSize = 5;

  final client = http.Client();

  final PagingController<int, Feed> paginationController =
      PagingController(firstPageKey: 0);

  List<Feed> feed = List.empty();

  @override
  void initState() {
    super.initState();
    paginationController.addPageRequestListener((pageKey) {
      pullFeed(pageKey);
    });
  }

  Future<void> pullFeed(int pageKey) async {
    var offset = pageKey;
    var take = pageSize;

    var uri =
        Uri.parse('https://co.solsynth.dev/api/feed?take=$take&offset=$offset');

    var res = await client.get(uri);
    if (res.statusCode == 200) {
      final result =
          PaginationResult.fromJson(jsonDecode(utf8.decode(res.bodyBytes)));
      final isLastPage = (result.data?.length ?? 0) < pageSize;
      if (isLastPage) {
        paginationController.appendLastPage(feed);
      } else {
        final feed = result.data!.map((x) => Feed.fromJson(x)).toList();
        final nextPageKey = pageKey + feed.length;
        paginationController.appendPage(feed, nextPageKey);
      }
    } else {
      paginationController.error = utf8.decode(res.bodyBytes);
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: PagedListView<int, Feed>(
        pagingController: paginationController,
        builderDelegate: PagedChildBuilderDelegate<Feed>(
          itemBuilder: (context, item, index) => FeedItem(
            item: item,
          ),
        ),
      ),
    );
  }

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