SolarAgent/lib/screens/explore.dart

import 'dart:convert';

import 'package:flutter/material.dart';
import 'package:go_router/go_router.dart';
import 'package:infinite_scroll_pagination/infinite_scroll_pagination.dart';
import 'package:solaragent/auth.dart';
import 'package:solaragent/models/feed.dart';
import 'package:solaragent/models/pagination.dart';
import 'package:http/http.dart' as http;
import 'package:solaragent/router.dart';
import 'package:solaragent/widgets/feed.dart';
import 'package:solaragent/screens/publish/moment_editor.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.count - pageKey) < pageSize;
      final items =
          result.data?.map((x) => Feed.fromJson(x)).toList() ?? List.empty();
      if (isLastPage || result.data == null) {
        paginationController.appendLastPage(items);
      } else {
        final nextPageKey = pageKey + items.length;
        paginationController.appendPage(items, nextPageKey);
      }
    } else {
      paginationController.error = utf8.decode(res.bodyBytes);
    }
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: RefreshIndicator(
        onRefresh: () async {
          paginationController.refresh();
        },
        child: PagedListView<int, Feed>(
          pagingController: paginationController,
          builderDelegate: PagedChildBuilderDelegate<Feed>(
            itemBuilder: (context, item, index) => FeedItem(
              item: item,
            ),
          ),
        ),
      ),
      floatingActionButton: FutureBuilder(
          future: authClient.isAuthorized(),
          builder: (context, snapshot) {
            if (snapshot.hasData && snapshot.data == true) {
              return FloatingActionButton(
                child: const Icon(Icons.edit),
                onPressed: () {
                  router.push("/post/moments").then((value) {
                    if (value == true) paginationController.refresh();
                  });
                },
              );
            } else {
              return Container();
            }
          }),
    );
  }

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