import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:shadcn_ui/shadcn_ui.dart';
import 'package:provider/provider.dart';
import 'package:google_fonts/google_fonts.dart';
import '../../../core/theme/app_color_scheme.dart';
import '../../../core/theme/app_spacing.dart';
import '../../../providers/asset_provider.dart';
import '../../../data/models/account_models.dart';
import '../../shared/ui_constants.dart';
import '../../components/neon_glow.dart';

/// 划转页面 - 币安风格
class TransferPage extends StatefulWidget {
  const TransferPage({super.key});

  @override
  State<TransferPage> createState() => _TransferPageState();
}

class _TransferPageState extends State<TransferPage> {
  final _amountController = TextEditingController();
  int _direction = 1; // 1: 资金→交易, 2: 交易→资金
  bool _isLoading = false;

  @override
  void initState() {
    super.initState();
    WidgetsBinding.instance.addPostFrameCallback((_) {
      context.read<AssetProvider>().refreshAll(force: true);
    });
  }

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

  /// 获取资金账户余额
  String get _fundBalance {
    final provider = context.read<AssetProvider>();
    return provider.fundAccount?.balance ?? provider.overview?.fundBalance ?? '0.00';
  }

  /// 获取交易账户 USDT 余额
  String get _tradeUsdtBalance {
    final provider = context.read<AssetProvider>();
    final usdtHolding = provider.tradeAccounts.firstWhere(
      (t) => t.coinCode.toUpperCase() == 'USDT',
      orElse: () => AccountTrade(
        id: 0,
        userId: 0,
        coinCode: 'USDT',
        quantity: '0',
        avgPrice: '1',
        totalCost: '0',
        currentValue: '0',
        profit: '0',
        profitRate: 0,
      ),
    );
    return usdtHolding.quantity;
  }

  /// 获取当前可用余额（根据方向）
  String get _availableBalance {
    return _direction == 1 ? _fundBalance : _tradeUsdtBalance;
  }

  /// 从账户名
  String get _fromLabel => _direction == 1 ? '资金账户' : '交易账户';
  String get _toLabel => _direction == 1 ? '交易账户' : '资金账户';
  String get _fromBalance => _direction == 1 ? _fundBalance : _tradeUsdtBalance;
  String get _toBalance => _direction == 1 ? _tradeUsdtBalance : _fundBalance;

  /// 执行划转
  Future<void> _doTransfer() async {
    final amount = _amountController.text;
    final available = double.tryParse(_availableBalance) ?? 0;
    final transferAmount = double.tryParse(amount) ?? 0;

    if (transferAmount <= 0) {
      _showSnackBar('请输入有效的划转金额');
      return;
    }

    if (transferAmount > available) {
      _showSnackBar('余额不足');
      return;
    }

    setState(() => _isLoading = true);

    try {
      final response = await context.read<AssetProvider>().transfer(
        direction: _direction,
        amount: amount,
      );

      if (mounted) {
        if (response.success) {
          _amountController.clear();
          _showSnackBar('划转成功');
          Navigator.of(context).pop(true);
        } else {
          _showSnackBar(response.message ?? '划转失败');
        }
      }
    } finally {
      if (mounted) {
        setState(() => _isLoading = false);
      }
    }
  }

  void _showSnackBar(String message) {
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(content: Text(message)),
    );
  }

  /// 设置快捷百分比金额
  void _setQuickAmount(double percent) {
    final available = double.tryParse(_availableBalance) ?? 0;
    final amount = available * percent;
    // 保留8位小数，去除末尾0
    _amountController.text = amount.toStringAsFixed(8).replaceAll(RegExp(r'\.?0+$'), '');
  }

  /// 切换方向
  void _toggleDirection() {
    setState(() {
      _direction = _direction == 1 ? 2 : 1;
    });
  }

  @override
  Widget build(BuildContext context) {
    final colorScheme = Theme.of(context).colorScheme;
    final isDark = Theme.of(context).brightness == Brightness.dark;

    return Scaffold(
      backgroundColor: colorScheme.background,
      appBar: AppBar(
        backgroundColor: Colors.transparent,
        elevation: 0,
        leading: IconButton(
          icon: Icon(Icons.arrow_back, color: colorScheme.onSurface),
          onPressed: () => Navigator.of(context).pop(),
        ),
        title: Text(
          '资金划转',
          style: GoogleFonts.spaceGrotesk(
            fontSize: 14,
            fontWeight: FontWeight.bold,
            color: colorScheme.onSurface,
          ),
        ),
        centerTitle: true,
      ),
      body: Consumer<AssetProvider>(
        builder: (context, provider, _) {
          return SingleChildScrollView(
            padding: AppSpacing.pagePadding,
            child: Column(
              children: [
                // 第一个卡片位置 - 带动画
                TweenAnimationBuilder<double>(
                  tween: Tween(begin: 0, end: 1),
                  duration: const Duration(milliseconds: 300),
                  builder: (context, value, child) {
                    return AnimatedSwitcher(
                      duration: const Duration(milliseconds: 300),
                      switchInCurve: Curves.easeInOut,
                      switchOutCurve: Curves.easeInOut,
                      transitionBuilder: (widget, animation) {
                        return SlideTransition(
                          position: Tween<Offset>(
                            begin: const Offset(0, -1),
                            end: Offset.zero,
                          ).animate(animation),
                          child: FadeTransition(
                            opacity: animation,
                            child: widget,
                          ),
                        );
                      },
                      child: _direction == 1
                          ? _buildAccountCard(
                              key: const ValueKey('from-card'),
                              label: '从',
                              accountName: _fromLabel,
                              balance: _fromBalance,
                              isDark: isDark,
                              colorScheme: colorScheme,
                            )
                          : _buildAccountCard(
                              key: const ValueKey('to-card-top'),
                              label: '到',
                              accountName: _toLabel,
                              balance: _toBalance,
                              isDark: isDark,
                              colorScheme: colorScheme,
                            ),
                    );
                  },
                ),

                // 方向切换按钮（固定在中间）
                GestureDetector(
                  onTap: _toggleDirection,
                  child: Container(
                    margin: EdgeInsets.symmetric(vertical: AppSpacing.sm),
                    padding: EdgeInsets.all(AppSpacing.sm + AppSpacing.xs),
                    decoration: BoxDecoration(
                      color: colorScheme.primary,
                      shape: BoxShape.circle,
                      boxShadow: [
                        BoxShadow(
                          color: colorScheme.primary.withOpacity(0.3),
                          blurRadius: 8,
                        ),
                      ],
                    ),
                    child: Icon(
                      Icons.swap_vert,
                      color: colorScheme.onPrimary,
                      size: 22,
                    ),
                  ),
                ),

                // 第二个卡片位置 - 带动画
                AnimatedSwitcher(
                  duration: const Duration(milliseconds: 300),
                  switchInCurve: Curves.easeInOut,
                  switchOutCurve: Curves.easeInOut,
                  transitionBuilder: (widget, animation) {
                    return SlideTransition(
                      position: Tween<Offset>(
                        begin: const Offset(0, 1),
                        end: Offset.zero,
                      ).animate(animation),
                      child: FadeTransition(
                        opacity: animation,
                        child: widget,
                      ),
                    );
                  },
                  child: _direction == 1
                      ? _buildAccountCard(
                          key: const ValueKey('to-card'),
                          label: '到',
                          accountName: _toLabel,
                          balance: _toBalance,
                          isDark: isDark,
                          colorScheme: colorScheme,
                        )
                      : _buildAccountCard(
                          key: const ValueKey('from-card-bottom'),
                          label: '从',
                          accountName: _fromLabel,
                          balance: _fromBalance,
                          isDark: isDark,
                          colorScheme: colorScheme,
                        ),
                ),

                SizedBox(height: AppSpacing.lg),

                // 金额输入卡片
                _buildAmountSection(colorScheme, isDark),

                SizedBox(height: AppSpacing.lg),

                // 确认按钮
                SizedBox(
                  width: double.infinity,
                  child: NeonButton(
                    text: _isLoading ? '处理中...' : '确认划转',
                    icon: _isLoading ? null : LucideIcons.arrowRightLeft,
                    type: NeonButtonType.primary,
                    onPressed: _isLoading ? null : _doTransfer,
                    height: 52,
                    showGlow: true,
                  ),
                ),

                SizedBox(height: AppSpacing.md),

                // 划转说明
                _buildTips(colorScheme),
              ],
            ),
          );
        },
      ),
    );
  }

  /// 账户卡片
  Widget _buildAccountCard({
    Key? key,
    required String label,
    required String accountName,
    required String balance,
    required bool isDark,
    required ColorScheme colorScheme,
  }) {
    return Container(
      key: key,
      width: double.infinity,
      padding: EdgeInsets.all(AppSpacing.md),
      decoration: BoxDecoration(
        color: isDark ? colorScheme.surfaceContainer : colorScheme.surfaceContainerHigh,
        borderRadius: BorderRadius.circular(AppRadius.lg),
        border: Border.all(
          color: colorScheme.outlineVariant.withOpacity(0.15),
        ),
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Row(
            children: [
              Container(
                padding: EdgeInsets.symmetric(horizontal: AppSpacing.sm, vertical: AppSpacing.xs),
                decoration: BoxDecoration(
                  color: colorScheme.primary.withOpacity(0.1),
                  borderRadius: BorderRadius.circular(AppRadius.sm),
                ),
                child: Text(
                  label,
                  style: TextStyle(
                    fontSize: 11,
                    fontWeight: FontWeight.w600,
                    color: colorScheme.primary,
                  ),
                ),
              ),
              SizedBox(width: AppSpacing.sm),
              Text(
                accountName,
                style: GoogleFonts.spaceGrotesk(
                  fontSize: 16,
                  fontWeight: FontWeight.w600,
                  color: colorScheme.onSurface,
                ),
              ),
            ],
          ),
          SizedBox(height: AppSpacing.sm),
          Row(
            children: [
              Text(
                '可用余额',
                style: TextStyle(
                  fontSize: 12,
                  color: colorScheme.onSurfaceVariant,
                ),
              ),
              SizedBox(width: AppSpacing.xs),
              Text(
                '$balance USDT',
                style: GoogleFonts.spaceGrotesk(
                  fontSize: 14,
                  fontWeight: FontWeight.bold,
                  color: colorScheme.onSurface,
                ),
              ),
            ],
          ),
        ],
      ),
    );
  }

  /// 金额输入区域
  Widget _buildAmountSection(ColorScheme colorScheme, bool isDark) {
    return Container(
      width: double.infinity,
      padding: EdgeInsets.all(AppSpacing.md),
      decoration: BoxDecoration(
        color: isDark ? colorScheme.surfaceContainer : colorScheme.surfaceContainerHigh,
        borderRadius: BorderRadius.circular(AppRadius.lg),
        border: Border.all(
          color: colorScheme.outlineVariant.withOpacity(0.15),
        ),
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(
            '划转金额',
            style: TextStyle(
              fontSize: 13,
              color: colorScheme.onSurfaceVariant,
            ),
          ),
          SizedBox(height: AppSpacing.sm),
          // 金额输入行
          Row(
            crossAxisAlignment: CrossAxisAlignment.end,
            children: [
              Expanded(
                child: TextField(
                  controller: _amountController,
                  keyboardType: const TextInputType.numberWithOptions(decimal: true),
                  inputFormatters: [
                    FilteringTextInputFormatter.allow(RegExp(r'^\d*\.?\d{0,8}')),
                  ],
                  style: GoogleFonts.spaceGrotesk(
                    fontSize: 18,
                    fontWeight: FontWeight.bold,
                    color: colorScheme.onSurface,
                  ),
                  decoration: InputDecoration(
                    hintText: '0.00',
                    hintStyle: GoogleFonts.spaceGrotesk(
                      fontSize: 18,
                      fontWeight: FontWeight.bold,
                      color: colorScheme.onSurfaceVariant.withOpacity(0.3),
                    ),
                    border: InputBorder.none,
                    contentPadding: EdgeInsets.zero,
                    isDense: true,
                  ),
                ),
              ),
              Padding(
                padding: EdgeInsets.only(bottom: 4),
                child: Text(
                  'USDT',
                  style: TextStyle(
                    fontSize: 14,
                    fontWeight: FontWeight.w600,
                    color: colorScheme.onSurfaceVariant,
                  ),
                ),
              ),
            ],
          ),
          SizedBox(height: AppSpacing.sm),
          // 快捷按钮行
          Row(
            children: [
              Text(
                '可用: ${_availableBalance}',
                style: TextStyle(
                  fontSize: 12,
                  color: colorScheme.onSurfaceVariant,
                ),
              ),
              Spacer(),
              _buildQuickButton('25%', 0.25, colorScheme),
              SizedBox(width: AppSpacing.xs),
              _buildQuickButton('50%', 0.50, colorScheme),
              SizedBox(width: AppSpacing.xs),
              _buildQuickButton('75%', 0.75, colorScheme),
              SizedBox(width: AppSpacing.xs),
              _buildQuickButton('全部', 1.0, colorScheme),
            ],
          ),
          if (_direction == 2) ...[
            SizedBox(height: AppSpacing.sm),
            Container(
              padding: EdgeInsets.all(AppSpacing.sm),
              decoration: BoxDecoration(
                color: AppColorScheme.warning.withOpacity(0.1),
                borderRadius: BorderRadius.circular(AppRadius.sm),
              ),
              child: Row(
                children: [
                  Icon(
                    LucideIcons.triangleAlert,
                    size: 14,
                    color: AppColorScheme.warning,
                  ),
                  SizedBox(width: AppSpacing.xs),
                  Expanded(
                    child: Text(
                      '仅支持 USDT 资产划转到资金账户',
                      style: TextStyle(
                        fontSize: 11,
                        color: AppColorScheme.warning,
                      ),
                    ),
                  ),
                ],
              ),
            ),
          ],
        ],
      ),
    );
  }

  /// 快捷百分比按钮
  Widget _buildQuickButton(String label, double percent, ColorScheme colorScheme) {
    return GestureDetector(
      onTap: () => _setQuickAmount(percent),
      child: Container(
        padding: EdgeInsets.symmetric(horizontal: AppSpacing.sm, vertical: AppSpacing.xs),
        decoration: BoxDecoration(
          color: colorScheme.primary.withOpacity(0.1),
          borderRadius: BorderRadius.circular(AppRadius.sm),
        ),
        child: Text(
          label,
          style: TextStyle(
            fontSize: 12,
            fontWeight: FontWeight.w600,
            color: colorScheme.primary,
          ),
        ),
      ),
    );
  }

  /// 划转说明
  Widget _buildTips(ColorScheme colorScheme) {
    return Container(
      padding: EdgeInsets.all(AppSpacing.md),
      decoration: BoxDecoration(
        color: colorScheme.surfaceContainerHighest,
        borderRadius: BorderRadius.circular(AppRadius.md),
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(
            '划转说明',
            style: GoogleFonts.spaceGrotesk(
              fontSize: 12,
              fontWeight: FontWeight.w600,
              color: colorScheme.onSurfaceVariant,
            ),
          ),
          SizedBox(height: AppSpacing.sm),
          _buildTipItem('资金账户用于充提，交易账户用于买卖币种', colorScheme),
          _buildTipItem('划转操作即时到账，不可撤销', colorScheme),
          _buildTipItem('交易账户只有 USDT 可直接划转到资金账户', colorScheme),
          _buildTipItem('其他币种需先卖出换成 USDT 后才能划转', colorScheme),
        ],
      ),
    );
  }

  Widget _buildTipItem(String text, ColorScheme colorScheme) {
    return Padding(
      padding: EdgeInsets.only(bottom: AppSpacing.xs),
      child: Row(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Container(
            width: 4,
            height: 4,
            margin: EdgeInsets.only(top: 6, right: AppSpacing.sm),
            decoration: BoxDecoration(
              color: colorScheme.onSurfaceVariant,
              shape: BoxShape.circle,
            ),
          ),
          Expanded(
            child: Text(
              text,
              style: TextStyle(
                fontSize: 11,
                color: colorScheme.onSurfaceVariant,
              ),
            ),
          ),
        ],
      ),
    );
  }
}