import 'dart:async';
import 'dart:math';

import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:get/get.dart';
import 'package:isekai_wiki/components/isekai_nav_bar.dart';
import 'package:isekai_wiki/components/recent_page_list.dart';
import 'package:isekai_wiki/models/user.dart';
import 'package:isekai_wiki/pages/tab_page.dart';
import 'package:web_smooth_scroll/web_smooth_scroll.dart';

import '../components/collapsed_tab.dart';
import '../global.dart';
import '../styles.dart';

enum HomeTabs { newest, followed }

class HomeController extends GetxController with GetSingleTickerProviderStateMixin {
  double _navSearchButtonOffset = 90;

  var showNavSearchButton = false.obs;
  var isScrolling = false.obs;

  StreamController? streamController;
  StreamSubscription? _streamSubscription;

  late TabController tabController;
  late TabsPageController tabsPageController;
  final ScrollController scrollController = ScrollController();

  VoidFutureCallback? onRefresh;

  @override
  void onInit() {
    tabController = TabController(length: 2, vsync: this);

    _navSearchButtonOffset = 48 * MediaQuery.of(Get.context!).textScaleFactor + 48;

    scrollController.addListener(() {
      if (scrollController.offset >= _navSearchButtonOffset && !showNavSearchButton.value) {
        showNavSearchButton.value = true;
      } else if (scrollController.offset < _navSearchButtonOffset && showNavSearchButton.value) {
        showNavSearchButton.value = false;
      }
    });

    tabsPageController = Get.find<TabsPageController>();

    tabsPageController.streamController.stream.listen((event) {
      if (event == "tap:home") {
        handleTapHomeTab();
      }
    });

    super.onInit();
  }

  @override
  void dispose() {
    _streamSubscription?.cancel();

    super.dispose();
  }

  Future<void> handleTapHomeTab() async {
    if (isScrolling.value) return;

    if (scrollController.offset != 0) {
      isScrolling.value = true;
      await scrollController.animateTo(
        0,
        duration: const Duration(milliseconds: 500),
        curve: Curves.fastOutSlowIn,
      );
      isScrolling.value = false;
    }
  }

  Future<void> handleRefresh() async {
    if (onRefresh != null) {
      await onRefresh!();
    }
  }
}

class HomeTab extends StatelessWidget {
  final VoidCallback? onSearchClick;

  const HomeTab({super.key, this.onSearchClick});

  Widget _buildNotificationIconButton() {
    final uc = Get.find<UserController>();

    return Obx(
      () => AnimatedOpacity(
        opacity: uc.isLoggedIn ? 1.0 : 0.0,
        duration: const Duration(milliseconds: 100),
        child: CupertinoButton(
          padding: EdgeInsets.zero,
          child: const Icon(CupertinoIcons.bell, size: 26, color: Styles.themeNavTitleColor),
          onPressed: () {},
        ),
      ),
    );
  }

  Widget _buildSearchIconButton() {
    final c = Get.find<HomeController>();

    return Obx(
      () => AnimatedOpacity(
        opacity: c.showNavSearchButton.value ? 1.0 : 0.0,
        duration: const Duration(milliseconds: 100),
        child: CupertinoButton(
          padding: EdgeInsets.zero,
          child: const Icon(CupertinoIcons.search, size: 26, color: Styles.themeNavTitleColor),
          onPressed: () {
            onSearchClick?.call();
          },
        ),
      ),
    );
  }

  @override
  Widget build(BuildContext context) {
    final c = Get.put(HomeController());

    return WebSmoothScroll(
      controller: c.scrollController,
      child: CustomScrollView(
        controller: c.scrollController,
        physics: const BouncingScrollPhysics(
          parent: AlwaysScrollableScrollPhysics(),
        ),
        slivers: <Widget>[
          IsekaiSliverNavigationBar(
            leading: _buildSearchIconButton(),
            backgroundColor: Styles.themeMainColor,
            brightness: Brightness.dark,
            largeTitle: const Text('首页', style: TextStyle(color: Styles.themeNavTitleColor)),
            border: Border.all(style: BorderStyle.none),
            trailing: _buildNotificationIconButton(),
          ),
          SliverPersistentHeader(
            delegate: _SliverAppBarDelegate(
              minHeight: 48,
              maxHeight: 48,
              child: Container(
                decoration: const BoxDecoration(
                  color: Styles.themeMainColor,
                  boxShadow: [
                    BoxShadow(
                      color: Styles.themeMainColor,
                      blurRadius: 0.0,
                      spreadRadius: 0.0,
                      offset: Offset(0, -2),
                    ),
                  ],
                ),
                padding: const EdgeInsets.only(bottom: 10, left: 12, right: 12),
                child: CupertinoButton(
                  color: Colors.white,
                  padding: const EdgeInsets.all(0),
                  onPressed: () {
                    onSearchClick?.call();
                  },
                  child: Wrap(
                    spacing: 14,
                    alignment: WrapAlignment.spaceBetween,
                    children: [
                      Container(
                        padding: const EdgeInsets.all(1),
                        child: const Icon(CupertinoIcons.search, color: Colors.black54),
                      ),
                      const Text("搜索页面...",
                          textAlign: TextAlign.center, style: TextStyle(color: Colors.black54))
                    ],
                  ),
                ),
              ),
            ),
          ),
          SliverPersistentHeader(
            pinned: true,
            delegate: _SliverAppBarDelegate(
              minHeight: 40.0,
              maxHeight: 40.0,
              child: Container(
                decoration: BoxDecoration(color: Colors.white, boxShadow: [
                  BoxShadow(
                    color: Colors.grey.withOpacity(0.2),
                    spreadRadius: 2,
                    blurRadius: 4,
                    offset: const Offset(0, 2),
                  )
                ]),
                child: Row(
                  children: [
                    SizedBox(
                      child: TabBar(
                        isScrollable: true,
                        controller: c.tabController,
                        indicatorColor: Styles.themeMainColor,
                        labelColor: Styles.themeMainColor,
                        unselectedLabelColor: Colors.black45,
                        tabs: const [CollapsedTabText('最新'), CollapsedTabText('关注')],
                        onTap: (int selected) {},
                      ),
                    ),
                    const Expanded(child: Text('')),
                  ],
                ),
              ),
            ),
          ),
          CupertinoSliverRefreshControl(
            onRefresh: c.handleRefresh,
          ),
          SliverSafeArea(
            top: false,
            bottom: false,
            minimum: const EdgeInsets.only(top: 12, bottom: 12),
            sliver: RecentPageList(
              scrollController: c.scrollController,
            ),
          ),
        ],
      ),
    );
  }
}

class _SliverAppBarDelegate extends SliverPersistentHeaderDelegate {
  _SliverAppBarDelegate({
    required this.minHeight,
    required this.maxHeight,
    required this.child,
  });

  final double minHeight;
  final double maxHeight;
  final Widget child;

  @override
  double get minExtent => minHeight;

  @override
  double get maxExtent => max(maxHeight, minHeight);

  @override
  Widget build(BuildContext context, double shrinkOffset, bool overlapsContent) {
    return SizedBox.expand(child: child);
  }

  @override
  bool shouldRebuild(_SliverAppBarDelegate oldDelegate) {
    return maxHeight != oldDelegate.maxHeight ||
        minHeight != oldDelegate.minHeight ||
        child != oldDelegate.child;
  }
}