import 'package:cached_network_image/cached_network_image.dart';
import 'package:flutter/material.dart';
import 'package:flutter_screenutil/flutter_screenutil.dart';
import 'package:get/get.dart';
import 'package:keyboard/base/base_view.dart';
import 'package:keyboard/module/character/content/character_group_content_view.dart';
import 'package:keyboard/resource/string.gen.dart';

import '../../resource/assets.gen.dart';
import 'character_controller.dart';

class CharacterView extends BaseView<CharacterController> {
  const CharacterView({super.key});

  @override
  backgroundColor() {
    return Colors.transparent;
  }

  @override
  Widget buildBody(BuildContext context) {
    return Scaffold(
      backgroundColor: Color(0xFFF6F5FA),
      body: Builder(
        builder: (context) {
          return NestedScrollView(

            headerSliverBuilder: (context, innerBoxIsScrolled) {
              return [
                /// **🔹 让背景图滑动时裁剪掉上方部分**
                SliverPersistentHeader(
                  pinned: true,
                  delegate: CharacterHeaderDelegate(
                    expandedHeight: 240.h,
                    minHeight: 100.h,
                    // bottomWidget: SizedBox(),
                    onTap: controller.clickMyKeyboard,
                  ),
                ),
                SliverPersistentHeader(
                  pinned: true,

                  // floating: true,
                  delegate: TabBarDelegate(
                    height: 180.h,
                    child: _bottomAppBar(),
                  ),
                ),
              ];
            },

            body: _pages(),
          );
        },
      ),
    );
  }

  /// **自定义 bottomAppBar**
  Widget _bottomAppBar() {
    return Container(
      decoration: ShapeDecoration(
        gradient: LinearGradient(
          begin: Alignment(0.50, -0.00),
          end: Alignment(0.50, 1.00),
          colors: [Color(0xFFEAE5FF), Color(0xFFF5F4F9)],
        ),
        shape: RoundedRectangleBorder(
          borderRadius: BorderRadius.only(
            topLeft: Radius.circular(20.r),
            topRight: Radius.circular(20.r),
          ),
        ),
      ),
      child: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        crossAxisAlignment: CrossAxisAlignment.start,
        mainAxisSize: MainAxisSize.min,
        children: [
          _customizeButton(),
          SizedBox(height: 14.h),
          Row(
            mainAxisAlignment: MainAxisAlignment.spaceBetween,
            children: [
              Assets.images.iconCharacterMarket.image(
                width: 73.w,
                height: 25.h,
              ),
              Obx(() {
                return DropdownButton<String>(
                  // hint: Text(''),
                  underline: Container(height: 0),
                  style: TextStyle(
                    color: Colors.black.withAlpha(102),
                    fontSize: 14.sp,
                    fontWeight: FontWeight.w400,
                  ),
                  icon: Assets.images.iconCharacterArrowDown.image(
                    width: 20.r,
                    height: 20.r,
                  ),
                  value: controller.currentKeyboardInfo.value?.name,
                  onChanged: (String? newValue) {
                    controller.updateSelectedValue(newValue);
                  },

                  items: List.generate(controller.keyboardInfoList.length, (
                    index,
                  ) {
                    String? value = controller.keyboardInfoList[index].name;
                    return DropdownMenuItem<String>(
                      value: value,
                      child: Column(
                        crossAxisAlignment: CrossAxisAlignment.start,
                        mainAxisSize: MainAxisSize.min,
                        children: [
                          Padding(
                            padding: EdgeInsets.symmetric(vertical: 8),
                            child: Text(
                              value ?? "",
                              style: TextStyle(
                                color: Colors.black.withAlpha(204),
                                fontSize: 14.sp,
                                fontWeight: FontWeight.w400,
                              ),
                            ),
                          ),
                          if (index != controller.keyboardInfoList.length - 1)
                            Divider(
                              color: Color(0xFFF6F6F6),
                              thickness: 1,
                              height: 1,
                            ),
                        ],
                      ),
                    );
                  }),
                );
              }),
            ],
          ),
          SizedBox(height: 15.h),
          tabBar(),
        ],
      ),
    );
  }

  // 定制按钮
  Widget _customizeButton() {
    return Container(
      margin: EdgeInsets.only(left: 16.w),
      width: 220.w,
      height: 56.h,
      padding: EdgeInsets.symmetric(horizontal: 10.w),
      decoration: ShapeDecoration(
        color: const Color(0xFF121212),
        shape: RoundedRectangleBorder(
          borderRadius: BorderRadius.circular(40.r),
        ),
      ),
      child: Row(
        mainAxisAlignment: MainAxisAlignment.start,
        children: [
          Assets.images.iconCharacterCustomized.image(
            width: 36.r,
            height: 36.r,
          ),
          SizedBox(width: 8.w),
          Column(
            crossAxisAlignment: CrossAxisAlignment.start,
            mainAxisAlignment: MainAxisAlignment.center,
            children: [
              Text(
                StringName.goCustomizeCharacter,
                textAlign: TextAlign.center,
                style: TextStyle(
                  color: Colors.white,
                  fontSize: 16.sp,
                  fontWeight: FontWeight.w500,
                ),
              ),
              Text(
                StringName.goCustomizeCharacterDesc,
                style: TextStyle(
                  color: Color(0xFFF5F4F9),
                  fontSize: 11.sp,
                  fontWeight: FontWeight.w400,
                ),
              ),
            ],
          ),
          Container(
            margin: EdgeInsets.only(left: 16.w),
            width: 24.r,
            height: 24.r,
            decoration: ShapeDecoration(
              color: Colors.white,
              shape: OvalBorder(),
            ),
            child: Assets.images.iconCharacterArrowRight.image(
              width: 16.r,
              height: 16.r,
            ),
          ),
        ],
      ),
    );
  }

  /// **TabBar**
  Widget tabBar() {
    return Obx(() {
      if (controller.characterGroupList.isEmpty) {
        return const SizedBox.shrink();
      }
      return TabBar(
        controller: controller.tabController.value,
        dividerHeight: 0,
        tabAlignment: TabAlignment.start,
        isScrollable: true,
        padding: EdgeInsets.symmetric(horizontal: 12.w),
        labelPadding: EdgeInsets.symmetric(horizontal: 4.w),
        indicator: const BoxDecoration(),
        onTap: (index) => controller.onTabChanged(index),
        tabs: List.generate(controller.characterGroupList.length, (index) {
          var e = controller.characterGroupList[index];
          bool isSelected = index == controller.currentTabBarIndex.value;
          return Container(
            width: 80.w,
            height: isSelected ? 38.h : 32.h,
            decoration:
                isSelected
                    ? BoxDecoration(
                      borderRadius: BorderRadius.circular(36.r),
                      image: DecorationImage(
                        image:
                            Assets.images.iconCharacterGroupSelected.provider(),
                        fit: BoxFit.cover,
                      ),
                    )
                    : BoxDecoration(
                      color: Colors.white.withAlpha(204),
                      borderRadius: BorderRadius.circular(36.r),
                    ),
            child: Row(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                if (e.iconUrl != null)
                  CachedNetworkImage(
                    imageUrl: e.iconUrl!,
                    width: 20.r,
                    height: 20.r,
                  ),

                Text(
                  e.name ?? "",
                  style: TextStyle(
                    color:
                        isSelected ? Colors.black : Colors.black.withAlpha(104),
                    fontSize: 14.sp,
                    fontWeight: FontWeight.w500,
                  ),
                ),
              ],
            ),
          );
        }),
      );
    });
  }

  Widget _pages() {
    return Obx(() {
      if (controller.characterGroupList.isEmpty) {
        return const Center(child: CircularProgressIndicator());
      }
      return PageView(
        controller: controller.pageController,
        onPageChanged: (index) {
          controller.onPageChanged(index);
        },
        children:
            controller.characterGroupList.map((group) {
              return CharacterGroupContentView();
            }).toList(),
      );
    });
  }
}

/// **🔹 让背景图滑动时裁剪掉上方部分**
class CharacterHeaderDelegate extends SliverPersistentHeaderDelegate {
  final double expandedHeight;
  final double minHeight;

  // final Widget bottomWidget;
  final VoidCallback onTap;

  CharacterHeaderDelegate({
    required this.expandedHeight,
    required this.minHeight,
    // required this.bottomWidget,
    required this.onTap,
  });

  @override
  Widget build(
    BuildContext context,
    double shrinkOffset,
    bool overlapsContent,
  ) {
    final currentVisibleHeight = (expandedHeight - shrinkOffset).clamp(
      minHeight,
      expandedHeight,
    );
    final tabBarOffset = expandedHeight - currentVisibleHeight; // 计算 TabBar 位移

    final opacity = 1 - currentVisibleHeight / expandedHeight;
    return Stack(
      clipBehavior: Clip.none,
      children: [
        // 背景图片，动态裁剪
        Positioned(
          top: 0,
          left: 0,
          right: 0,
          height: currentVisibleHeight,
          child: ClipRect(
            child: Image.asset(
              Assets.images.bgCharacterBoyBanner.path,
              fit: BoxFit.cover,
              height: expandedHeight,
              alignment: Alignment.topCenter,
            ),
          ),
        ),

        // 遮罩层 Positioned（用于控制背景的可见性）
        Positioned(
          top: 0,
          left: 0,
          right: 0,
          height: currentVisibleHeight,
          child: Container(color: Colors.black.withValues(alpha: opacity)),
        ),
        Positioned(
          top: 0,
          child: SafeArea(
            child: GestureDetector(
              onTap: onTap,
              child: Container(
                margin: EdgeInsets.symmetric(horizontal: 16.w),
                width: 96.w,
                height: 32.h,
                padding: const EdgeInsets.symmetric(horizontal: 6, vertical: 4),
                decoration: ShapeDecoration(
                  color: Colors.white.withValues(alpha: 153),
                  shape: RoundedRectangleBorder(
                    borderRadius: BorderRadius.circular(10),
                  ),
                ),
                child: Row(
                  mainAxisAlignment: MainAxisAlignment.start,
                  crossAxisAlignment: CrossAxisAlignment.center,
                  spacing: 4.r,
                  children: [
                    Container(
                      width: 24.r,
                      height: 24.r,
                      clipBehavior: Clip.antiAlias,
                      decoration: BoxDecoration(),
                      child: Assets.images.iconCharacterKeyboard.image(
                        width: 24.r,
                        height: 24.r,
                      ),
                    ),
                    Text(
                      StringName.myKeyboard,
                      textAlign: TextAlign.center,
                      style: TextStyle(
                        color: Colors.black.withAlpha(204),
                        fontSize: 14.sp,
                        fontWeight: FontWeight.w400,
                      ),
                    ),
                  ],
                ),
              ),
            ),
          ),
        ),
        // TabBar 定位
        // Positioned(
        //   bottom: tabBarOffset,
        //   left: 0,
        //   right: 0,
        //   child: Transform.translate(
        //     offset: Offset(0, tabBarOffset),
        //     child: bottomWidget,
        //   ),
        // ),
      ],
    );
  }

  @override
  double get maxExtent => expandedHeight;

  @override
  double get minExtent => minHeight;

  @override
  bool shouldRebuild(covariant SliverPersistentHeaderDelegate oldDelegate) =>
      true;
}

class TabBarDelegate extends SliverPersistentHeaderDelegate {
  final Widget child;
  final double height;

  TabBarDelegate({required this.child, required this.height});

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

  @override
  double get maxExtent => height; // 固定最大高度

  @override
  double get minExtent => height; // 固定最小高度

  @override
  bool shouldRebuild(covariant SliverPersistentHeaderDelegate oldDelegate) =>
      true;
}