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/glass_panel.dart';
import '../../components/neon_glow.dart';

/// 划转页面 - 资金账户与交易账户互相划转
class TransferPage extends StatefulWidget {
  const TransferPage({super.key});

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

class _TransferPageState extends State<TransferPage> {
  final _amountController = TextEditingController();
  final _formKey = GlobalKey<ShadFormState>();
  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;
  }

  /// 执行划转
  Future<void> _doTransfer() async {
    if (!_formKey.currentState!.saveAndValidate()) return;

    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); // 返回成功标记
        } 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)),
    );
  }

  @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: 18,
            fontWeight: FontWeight.bold,
            color: colorScheme.onSurface,
          ),
        ),
        centerTitle: true,
      ),
      body: Consumer<AssetProvider>(
        builder: (context, provider, _) {
          return SingleChildScrollView(
            padding: AppSpacing.pagePadding,
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: [
                // 说明卡片
                _buildInfoCard(colorScheme),
                SizedBox(height: AppSpacing.lg),

                // 划转方向选择
                _buildDirectionSelector(colorScheme),
                SizedBox(height: AppSpacing.lg),

                // 账户余额显示
                _buildBalanceCards(provider, colorScheme, isDark),
                SizedBox(height: AppSpacing.lg),

                // 金额输入
                _buildAmountInput(colorScheme),
                SizedBox(height: AppSpacing.xl),

                // 确认按钮
                _buildSubmitButton(colorScheme),

                SizedBox(height: AppSpacing.lg),

                // 提示信息
                _buildTips(colorScheme),
              ],
            ),
          );
        },
      ),
    );
  }

  /// 说明卡片
  Widget _buildInfoCard(ColorScheme colorScheme) {
    return Container(
      padding: EdgeInsets.all(AppSpacing.md),
      decoration: BoxDecoration(
        color: colorScheme.primary.withOpacity(0.1),
        borderRadius: BorderRadius.circular(AppRadius.md),
        border: Border.all(
          color: colorScheme.primary.withOpacity(0.2),
        ),
      ),
      child: Row(
        children: [
          Icon(
            LucideIcons.info,
            size: 18,
            color: colorScheme.primary,
          ),
          SizedBox(width: AppSpacing.sm),
          Expanded(
            child: Text(
              _direction == 1
                  ? '资金账户 → 交易账户：相当于用资金账户的钱购买 USDT'
                  : '交易账户 → 资金账户：相当于卖掉 USDT 换回资金',
              style: TextStyle(
                fontSize: 12,
                color: colorScheme.onSurfaceVariant,
              ),
            ),
          ),
        ],
      ),
    );
  }

  /// 划转方向选择器
  Widget _buildDirectionSelector(ColorScheme colorScheme) {
    return GlassPanel(
      padding: EdgeInsets.all(AppSpacing.md),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(
            '划转方向',
            style: GoogleFonts.spaceGrotesk(
              fontSize: 14,
              fontWeight: FontWeight.w600,
              color: colorScheme.onSurface,
            ),
          ),
          SizedBox(height: AppSpacing.md),
          Row(
            children: [
              Expanded(
                child: _DirectionCard(
                  title: '资金账户',
                  subtitle: '交易账户',
                  icon: LucideIcons.arrowRight,
                  isSelected: _direction == 1,
                  onTap: () => setState(() => _direction = 1),
                ),
              ),
              SizedBox(width: AppSpacing.sm),
              Expanded(
                child: _DirectionCard(
                  title: '交易账户',
                  subtitle: '资金账户',
                  icon: LucideIcons.arrowRight,
                  isSelected: _direction == 2,
                  onTap: () => setState(() => _direction = 2),
                ),
              ),
            ],
          ),
          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,
                      ),
                    ),
                  ),
                ],
              ),
            ),
          ],
        ],
      ),
    );
  }

  /// 账户余额卡片
  Widget _buildBalanceCards(AssetProvider provider, ColorScheme colorScheme, bool isDark) {
    final fundBalance = provider.fundAccount?.balance ?? provider.overview?.fundBalance ?? '0.00';
    final tradeUsdtBalance = _tradeUsdtBalance;

    return Row(
      children: [
        Expanded(
          child: _BalanceCard(
            title: '资金账户',
            balance: fundBalance,
            isActive: _direction == 1,
            colorScheme: colorScheme,
          ),
        ),
        SizedBox(width: AppSpacing.sm),
        // 中间的转换图标
        Container(
          width: 40,
          height: 40,
          decoration: BoxDecoration(
            color: colorScheme.primary.withOpacity(0.1),
            shape: BoxShape.circle,
          ),
          child: Icon(
            _direction == 1 ? LucideIcons.arrowRight : LucideIcons.arrowLeft,
            color: colorScheme.primary,
            size: 18,
          ),
        ),
        SizedBox(width: AppSpacing.sm),
        Expanded(
          child: _BalanceCard(
            title: '交易账户(USDT)',
            balance: tradeUsdtBalance,
            isActive: _direction == 2,
            colorScheme: colorScheme,
          ),
        ),
      ],
    );
  }

  /// 金额输入
  Widget _buildAmountInput(ColorScheme colorScheme) {
    final available = _availableBalance;

    return GlassPanel(
      padding: EdgeInsets.all(AppSpacing.md),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Row(
            mainAxisAlignment: MainAxisAlignment.spaceBetween,
            children: [
              Text(
                '划转金额',
                style: GoogleFonts.spaceGrotesk(
                  fontSize: 14,
                  fontWeight: FontWeight.w600,
                  color: colorScheme.onSurface,
                ),
              ),
              GestureDetector(
                onTap: () {
                  _amountController.text = available;
                },
                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(
                    '全部',
                    style: TextStyle(
                      fontSize: 12,
                      color: colorScheme.primary,
                      fontWeight: FontWeight.w600,
                    ),
                  ),
                ),
              ),
            ],
          ),
          SizedBox(height: AppSpacing.sm),
          Text(
            '可用: $available USDT',
            style: TextStyle(
              fontSize: 12,
              color: colorScheme.onSurfaceVariant,
            ),
          ),
          SizedBox(height: AppSpacing.md),
          ShadForm(
            key: _formKey,
            child: ShadInputFormField(
              id: 'amount',
              controller: _amountController,
              placeholder: const Text('请输入划转金额'),
              keyboardType: const TextInputType.numberWithOptions(decimal: true),
              inputFormatters: [
                FilteringTextInputFormatter.allow(RegExp(r'^\d*\.?\d{0,8}')),
              ],
              validator: (value) {
                if (value == null || value.isEmpty) {
                  return '请输入划转金额';
                }
                final amount = double.tryParse(value);
                if (amount == null || amount <= 0) {
                  return '请输入有效金额';
                }
                final available = double.tryParse(_availableBalance) ?? 0;
                if (amount > available) {
                  return '余额不足';
                }
                return null;
              },
            ),
          ),
        ],
      ),
    );
  }

  /// 提交按钮
  Widget _buildSubmitButton(ColorScheme colorScheme) {
    return SizedBox(
      width: double.infinity,
      child: NeonButton(
        text: _isLoading ? '处理中...' : '确认划转',
        type: NeonButtonType.primary,
        onPressed: _isLoading ? null : _doTransfer,
        height: 52,
        showGlow: true,
      ),
    );
  }

  /// 提示信息
  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,
              ),
            ),
          ),
        ],
      ),
    );
  }
}

/// 方向选择卡片
class _DirectionCard extends StatelessWidget {
  final String title;
  final String subtitle;
  final IconData icon;
  final bool isSelected;
  final VoidCallback onTap;

  const _DirectionCard({
    required this.title,
    required this.subtitle,
    required this.icon,
    required this.isSelected,
    required this.onTap,
  });

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

    return GestureDetector(
      onTap: onTap,
      child: AnimatedContainer(
        duration: const Duration(milliseconds: 200),
        padding: EdgeInsets.all(AppSpacing.md),
        decoration: BoxDecoration(
          color: isSelected
              ? colorScheme.primary.withOpacity(0.15)
              : colorScheme.surfaceContainerHigh,
          borderRadius: BorderRadius.circular(AppRadius.md),
          border: isSelected
              ? Border.all(color: colorScheme.primary.withOpacity(0.5))
              : null,
        ),
        child: Column(
          children: [
            Row(
              mainAxisAlignment: MainAxisAlignment.center,
              children: [
                Text(
                  title,
                  style: TextStyle(
                    fontSize: 11,
                    color: colorScheme.onSurfaceVariant,
                  ),
                ),
                SizedBox(width: AppSpacing.xs),
                Icon(
                  icon,
                  size: 12,
                  color: colorScheme.onSurfaceVariant,
                ),
                SizedBox(width: AppSpacing.xs),
                Text(
                  subtitle,
                  style: TextStyle(
                    fontSize: 11,
                    color: isSelected ? colorScheme.primary : colorScheme.onSurfaceVariant,
                    fontWeight: isSelected ? FontWeight.w600 : FontWeight.normal,
                  ),
                ),
              ],
            ),
            if (isSelected) ...[
              SizedBox(height: AppSpacing.xs),
              Icon(
                LucideIcons.check,
                size: 14,
                color: colorScheme.primary,
              ),
            ],
          ],
        ),
      ),
    );
  }
}

/// 余额卡片
class _BalanceCard extends StatelessWidget {
  final String title;
  final String balance;
  final bool isActive;
  final ColorScheme colorScheme;

  const _BalanceCard({
    required this.title,
    required this.balance,
    required this.isActive,
    required this.colorScheme,
  });

  @override
  Widget build(BuildContext context) {
    return AnimatedContainer(
      duration: const Duration(milliseconds: 200),
      padding: EdgeInsets.all(AppSpacing.md),
      decoration: BoxDecoration(
        color: isActive
            ? colorScheme.primary.withOpacity(0.1)
            : colorScheme.surfaceContainerHigh,
        borderRadius: BorderRadius.circular(AppRadius.md),
        border: isActive
            ? Border.all(color: colorScheme.primary.withOpacity(0.3))
            : null,
      ),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          Text(
            title,
            style: TextStyle(
              fontSize: 10,
              color: colorScheme.onSurfaceVariant,
            ),
          ),
          SizedBox(height: AppSpacing.xs),
          Text(
            balance,
            style: GoogleFonts.spaceGrotesk(
              fontSize: 16,
              fontWeight: FontWeight.bold,
              color: isActive ? colorScheme.primary : colorScheme.onSurface,
            ),
          ),
          Text(
            'USDT',
            style: TextStyle(
              fontSize: 10,
              color: colorScheme.onSurfaceVariant,
            ),
          ),
        ],
      ),
    );
  }
}