didvan-app/lib/views/home/statistics/statistics.dart

import 'dart:math';

import 'package:didvan/config/design_config.dart';
import 'package:didvan/config/theme_data.dart';
import 'package:didvan/constants/assets.dart';
import 'package:didvan/models/category.dart';
import 'package:didvan/models/enums.dart';
import 'package:didvan/models/requests/radar.dart';
import 'package:didvan/views/home/statistics/statistics_state.dart';
import 'package:didvan/views/home/widgets/categories_gird.dart';
import 'package:didvan/views/home/widgets/categories_list.dart';
import 'package:didvan/views/home/widgets/logo_app_bar.dart';
import 'package:didvan/views/home/widgets/overview/radar.dart';
import 'package:didvan/views/widgets/animated_visibility.dart';
import 'package:didvan/views/widgets/didvan/text.dart';
import 'package:didvan/views/widgets/state_handlers/empty_state.dart';
import 'package:didvan/views/widgets/state_handlers/sliver_state_handler.dart';
import 'package:flutter/material.dart';
import 'package:provider/provider.dart';

class Statistics extends StatefulWidget {
  const Statistics({Key? key}) : super(key: key);

  @override
  State<Statistics> createState() => _RadarState();
}

class _RadarState extends State<Statistics> {
  final ScrollController _scrollController = ScrollController();

  bool _isAnimating = false;

  @override
  void initState() {
    _scrollController.addListener(() {
      _handleAnimations();
    });
    final state = context.read<StatisticsState>();
    state.addListener(() {
      if (state.shouldColapse && mounted) {
        _handleAnimations(true);
        state.shouldColapse = false;
      }
    });
    state.init();
    super.initState();
  }

  @override
  Widget build(BuildContext context) {
    return Consumer<StatisticsState>(
      builder: (context, state, child) => Stack(
        children: [
          CustomScrollView(
            physics: _isAnimating
                ? const NeverScrollableScrollPhysics()
                : const ClampingScrollPhysics(),
            controller: _scrollController,
            slivers: [
              const SliverToBoxAdapter(child: LogoAppBar()),
              if (state.appState != AppState.failed)
                const SliverToBoxAdapter(
                  child: SizedBox(height: 156),
                ),
              if (state.appState != AppState.failed)
                SliverPadding(
                  padding: const EdgeInsets.only(right: 16, bottom: 20),
                  sliver: SliverToBoxAdapter(
                    child: Align(
                      alignment: Alignment.centerRight,
                      child: AnimatedVisibility(
                        isVisible: !state.isColapsed,
                        duration: DesignConfig.lowAnimationDuration,
                        child: DidvanText(
                          'شاخص‌های منتخب',
                          style: Theme.of(context).textTheme.subtitle1,
                          color: Theme.of(context).colorScheme.title,
                        ),
                      ),
                    ),
                  ),
                ),
              SliverStateHandler<StatisticsState>(
                onRetry: () => state.getStatistics(page: state.page),
                state: state,
                itemPadding: const EdgeInsets.only(
                  bottom: 20,
                  left: 16,
                  right: 16,
                ),
                enableEmptyState: state.statistics.isEmpty,
                emptyState: Padding(
                  padding: const EdgeInsets.only(bottom: 120),
                  child: EmptyState(
                    asset: Assets.emptyResult,
                    title: 'موردی برای نمایش وجود ندارد.',
                  ),
                ),
                placeholder: RadarOverview.placeholder,
                builder: (context, state, index) {
                  index += 2;
                  if (index % 15 == 0 && state.lastPage != state.page) {
                    state.getStatistics(page: state.page + 1);
                  }
                  index -= 2;
                  if (index >= state.statistics.length) {
                    return RadarOverview.placeholder;
                  }
                  final radar = state.statistics[index];
                  return RadarOverview(
                    radar: radar,
                    onMarkChanged: state.changeMark,
                    onCommentsChanged: (id, count) => {},
                    radarRequestArgs: RadarRequestArgs(
                      page: state.page,
                      categories:
                          List.from(state.selectedCats.map((cat) => cat.id)),
                      isSingleItem: false,
                    ),
                  );
                },
                childCount: state.statistics.length +
                    (state.lastPage == state.page ? 0 : 3),
              ),
              if (state.statistics.length == 1)
                const SliverToBoxAdapter(
                  child: SizedBox(height: 320),
                ),
            ],
          ),
          if (state.appState != AppState.failed)
            CategoriesRow1(
              onSelected: _onCategorySelected,
              categories: state.categories,
              isColapsed: state.isColapsed,
              topPadding: 120,
            ),
          if (state.appState != AppState.failed)
            CategoriesList(
              isRadar: false,
              categories: state.categories,
              isColapsed: state.isColapsed,
              onSelected: () => state.getStatistics(page: 1),
              selectedCats: state.selectedCats,
            ),
        ],
      ),
    );
  }

  void _onCategorySelected(CategoryData category) {
    final state = context.read<StatisticsState>();
    state.selectedCats.clear();
    if (category.id != 0) {
      state.selectedCats.add(category);
    }
    state.getStatistics(page: 1);
  }

  void _handleAnimations([bool forceAnimate = false]) async {
    final state = context.read<StatisticsState>();
    if (_isAnimating) return;
    final double position = _scrollController.offset;
    if (position > 5 && !state.isColapsed || forceAnimate) {
      state.isScrolled = true;
      _isAnimating = true;
      setState(() {});
      await _scrollController.animateTo(
        200,
        duration: DesignConfig.mediumAnimationDuration,
        curve: Curves.easeIn,
      );
      _isAnimating = false;
      setState(() {});
    } else if (position <
            min(_scrollController.position.maxScrollExtent, 200) &&
        state.isColapsed) {
      state.isScrolled = false;
      _isAnimating = true;
      setState(() {});
      await _scrollController.animateTo(
        0,
        duration: DesignConfig.mediumAnimationDuration,
        curve: Curves.easeIn,
      );
      _isAnimating = false;
      setState(() {});
    }
  }

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