flutter_wisetronic/lib/widgets/desktop/product_search.dart

import 'package:dio/dio.dart';
import 'package:flappy_search_bar/flappy_search_bar.dart';
import 'package:flutter/material.dart';

import '../../constants.dart';
import '../../events/eventbus.dart';
import '../../events/events.dart';
import '../../generated/l10n.dart';
import '../../models/business.dart';
import '../../models/product.dart';
import '../../pages/product_detail_page.dart';
import '../../utils/http_util.dart';
import '../../utils/utils.dart';
import '../../widgets/general/bottom_nav.dart';
import '../../widgets/general/breadcrumbs.dart';
import '../../widgets/general/navigationbar.dart';
import 'product_item.dart';

class ProductSearch extends StatefulWidget {
  final Business business;

  const ProductSearch(this.business, {Key key}) : super(key: key);

  @override
  State<StatefulWidget> createState() => ProductSearchState();
}

class ProductSearchState extends State<ProductSearch> {

  double sideSpace = 0;
  double mainSpace = 1200;
  double rate = 1;

  int page = 1;
  int numPerPage = 10;
  int lastResultSize = 0;
  double lastBottomPosition = 0;
  String lastKeyword = '';

  SearchBarController _controller = SearchBarController<Product>();

  @override
  Widget build(BuildContext context) {

    if (MediaQuery.of(context).size.width <= 1200) {
      mainSpace = MediaQuery.of(context).size.width;
      sideSpace = 0;
    } else {
      mainSpace = 1200;
      sideSpace = (MediaQuery.of(context).size.width - 1200) / 2;
    }
    rate = mainSpace / 1200;

    return Scaffold(
      appBar: MiniNavigationBar(
        title: S.of(context).search_product,
        back: true,
        breadCrumbs: [
          BreadCrumb(S.of(context).search_product, null),
        ],
        breadCrumbHeight: Constants.BREADCRUMB_HEIGHT,
      ),
      drawer: null,
      body: SafeArea(
        child: Container(
          child: Row(
            children: [
              Container(
                width: sideSpace,
              ),
              Expanded(
                child: Padding(
                  padding: const EdgeInsets.symmetric(horizontal: 16.0),
                  child: NotificationListener<ScrollNotification>(
                    child: SearchBar(
                      searchBarController: _controller,
                      minimumChars: 2,
                      hintText: S.of(context).enter_keyword,
                      cancellationWidget: Text(
                        S.of(context).cancel,
                      ),
                      onSearch: search,
                      onItemFound: (Product searchProduct, int index) {
                        return ProductItem(
                          searchProduct,
                          widget.business,
                          horizontal: true,
                        );
                      },
                      onError: (error) {
                        return Center(
                          child: Text("$error"),
                        );
                      },
                      emptyWidget: Center(
                        child: Text(
                          S.of(context).empty_result_change_keyword,
                        ),
                      ),
                    ),
                    onNotification: (notification) {
                      if (notification.metrics.atEdge) {
                        print('fff: $page, $lastBottomPosition, ${notification.metrics.pixels}');
                        if (page != 0 && lastResultSize >= numPerPage && notification.metrics.pixels != 0) {
                          if (notification.metrics.pixels > lastBottomPosition) {
                            lastBottomPosition = notification.metrics.pixels;
                            page += 1;
                            _controller.replayLastSearch();
                          }
                        }
                      }
                      return true;
                    },
                  ),
                ),
              ),
              Container(
                width: sideSpace,
              ),
            ],
          ),
        ),
      ),
      bottomNavigationBar: BottomNav(),
    );
  }

  Future<List<Product>> search(String keyword) async {
    if (lastKeyword != keyword) {
      page = 1;
    }
    lastKeyword = keyword;
    var result = await HttpUtil.httpGet('v1/search-store-product2',
      queryParameters: {
        'store_id': widget.business.id,
        'keyword': keyword,
        'page': page,
        'num_per_page': numPerPage,
      },
      returnError: true,
    );
    if (result is DioError) {
      if (result.response != null) {
        throw RuntimeError(result.response.data);
      } else {
        throw RuntimeError(result.message);
      }
    } else if (result != null && result is List) {
      lastBottomPosition = 0;
      var r = result.map((e) => Product.fromJson(e)).toList();
      lastResultSize = r.length;
      if (lastResultSize < numPerPage) {
        page = 1;
      }
      return r;
    }
    return [];
  }

  @override
  void initState() {
    super.initState();
    eventBus.on<OnCartInfoUpdated>().listen((event) {
      if (mounted) {
        setState(() {});
      }
    });
  }

  void _showProductDetail(Product p) {
    Navigator.push(
      context,
      MaterialPageRoute(
          builder: (context) => ProductDetailPage(
            product: p,
            business: widget.business,
          )),
    );
  }
}