import { Image } from 'expo-image';
import { useRouter } from 'expo-router';
import React, { forwardRef, useImperativeHandle, useState } from 'react';
import {
    Alert,
    Modal,
    ScrollView,
    StyleSheet,
    Switch,
    Text,
    TextInput,
    TouchableOpacity,
    View,
} from 'react-native';
import { useSafeAreaInsets } from 'react-native-safe-area-context';

import { Address, getDefaultAddress } from '@/services/address';
import { GoodsDetail, previewSubmit, PreviewSubmitResult, submitOrder } from '@/services/mall';

interface CheckoutModalProps {
  data: GoodsDetail;
  goodsId: string;
  subjectId?: string;
}

export interface CheckoutModalRef {
  show: (preview: PreviewSubmitResult) => void;
  close: () => void;
}

export const CheckoutModal = forwardRef<CheckoutModalRef, CheckoutModalProps>(
  ({ data, goodsId, subjectId }, ref) => {
    const router = useRouter();
    const insets = useSafeAreaInsets();

    const [visible, setVisible] = useState(false);
    const [preview, setPreview] = useState<PreviewSubmitResult | null>(null);
    const [address, setAddress] = useState<Address | null>(null);
    const [quantity, setQuantity] = useState(1);
    const [phone, setPhone] = useState('');
    const [checked, setChecked] = useState(true);
    const [useWallet, setUseWallet] = useState(false);
    const [payType, setPayType] = useState<'alipay' | 'wxpay'>('alipay');
    const [submitting, setSubmitting] = useState(false);

    useImperativeHandle(ref, () => ({
      show: (previewData: PreviewSubmitResult) => {
        setPreview(previewData);
        setVisible(true);
        loadAddress();
      },
      close: () => {
        setVisible(false);
      },
    }));

    // 加载默认地址
    const loadAddress = async () => {
      try {
        const addr = await getDefaultAddress();
        setAddress(addr);
      } catch (error) {
        console.error('加载地址失败:', error);
      }
    };

    // 计算最终价格
    const lastPrice = preview
      ? data.sellType === 2
        ? preview.depositAmount || 0
        : preview.paymentAmount
      : data.price;

    // 增加数量
    const increment = async () => {
      if (subjectId) return; // 秒杀不能改数量
      if (quantity >= 5) return;
      const newQty = quantity + 1;
      setQuantity(newQty);
      // 重新获取价格
      const newPreview = await previewSubmit({ goodsId, quantity: newQty, subjectId });
      if (newPreview) setPreview(newPreview);
    };

    // 减少数量
    const decrement = async () => {
      if (quantity <= 1) return;
      const newQty = quantity - 1;
      setQuantity(newQty);
      const newPreview = await previewSubmit({ goodsId, quantity: newQty, subjectId });
      if (newPreview) setPreview(newPreview);
    };

    // 提交订单
    const handlePay = async () => {
      if (!address) {
        Alert.alert('提示', '请选择收货地址');
        return;
      }
      if (data.sellType === 2 && !phone) {
        Alert.alert('提示', '请填写尾款提醒手机号');
        return;
      }
      if (!checked) {
        Alert.alert('提示', '请勾选协议');
        return;
      }

      setSubmitting(true);
      try {
        const paymentType = useWallet ? 'WALLET' : payType === 'alipay' ? 'ALIPAY' : 'WXPAY';
        const result = await submitOrder({
          goodsId: data.id,
          paymentType,
          addressBookId: address.id,
          quantity,
          restNotifyMobile: phone,
          subjectId,
        });

        if (result) {
          if (result.paySuccess) {
            setVisible(false);
            Alert.alert('成功', '支付成功', [
              { text: '查看订单', onPress: () => router.push('/orders' as any) },
            ]);
          } else {
            // 需要跳转支付
            Alert.alert('提示', '请在支付页面完成支付');
          }
        }
      } catch (error) {
        console.error('提交订单失败:', error);
        Alert.alert('错误', '提交订单失败');
      }
      setSubmitting(false);
    };

    // 选择地址
    const selectAddress = () => {
      setVisible(false);
      router.push('/address?type=1' as any);
    };

    return (
      <Modal visible={visible} transparent animationType="slide">
        <View style={styles.overlay}>
          <TouchableOpacity style={styles.mask} onPress={() => setVisible(false)} />
          <View style={[styles.content, { paddingBottom: insets.bottom + 20 }]}>
            {/* 标题 */}
            <View style={styles.header}>
              <Text style={styles.title}>确认订单</Text>
              <TouchableOpacity onPress={() => setVisible(false)}>
                <Text style={styles.closeBtn}>×</Text>
              </TouchableOpacity>
            </View>

            <ScrollView style={styles.scrollContent} showsVerticalScrollIndicator={false}>
              {/* 商品信息 */}
              <View style={styles.goodsInfo}>
                <Image source={data.cover} style={styles.goodsImage} contentFit="cover" />
                <View style={styles.goodsDetail}>
                  <Text style={styles.goodsName} numberOfLines={2}>{data.name}</Text>
                  <View style={styles.priceRow}>
                    <Text style={styles.price}>¥{data.subjectPrice || data.price}</Text>
                    {data.sellType === 2 && (
                      <Text style={styles.deposit}>定金：¥{data.deposit}</Text>
                    )}
                  </View>
                  {/* 数量选择 */}
                  <View style={styles.quantityRow}>
                    <TouchableOpacity style={styles.qtyBtn} onPress={decrement}>
                      <Text style={styles.qtyBtnText}>-</Text>
                    </TouchableOpacity>
                    <Text style={styles.qtyNum}>{quantity}</Text>
                    <TouchableOpacity
                      style={[styles.qtyBtn, subjectId ? styles.qtyBtnDisabled : null]}
                      onPress={increment}
                    >
                      <Text style={styles.qtyBtnText}>+</Text>
                    </TouchableOpacity>
                  </View>
                </View>
              </View>

              {/* 优惠券 */}
              <View style={styles.row}>
                <Text style={styles.rowLabel}>优惠券</Text>
                <Text style={styles.rowValue}>-¥{preview?.couponAmount || 0}</Text>
              </View>

              {/* 钱包支付 */}
              {preview?.cash && (
                <View style={styles.row}>
                  <Text style={styles.rowLabel}>
                    使用钱包支付 <Text style={styles.balance}>(余额：¥{preview.cash.balance})</Text>
                  </Text>
                  <Switch value={useWallet} onValueChange={setUseWallet} />
                </View>
              )}

              {/* 支付方式 */}
              {!useWallet && (
                <View style={styles.payTypeSection}>
                  <TouchableOpacity
                    style={styles.payTypeItem}
                    onPress={() => setPayType('alipay')}
                  >
                    <Text style={styles.payTypeName}>支付宝</Text>
                    <View style={[styles.radio, payType === 'alipay' && styles.radioActive]} />
                  </TouchableOpacity>
                  <TouchableOpacity
                    style={styles.payTypeItem}
                    onPress={() => setPayType('wxpay')}
                  >
                    <Text style={styles.payTypeName}>微信支付</Text>
                    <View style={[styles.radio, payType === 'wxpay' && styles.radioActive]} />
                  </TouchableOpacity>
                </View>
              )}

              {/* 尾款手机号 */}
              {data.sellType === 2 && (
                <View style={styles.phoneRow}>
                  <Text style={styles.phoneLabel}>
                    <Text style={styles.required}>*</Text> 尾款提醒手机号
                  </Text>
                  <TextInput
                    style={styles.phoneInput}
                    value={phone}
                    onChangeText={setPhone}
                    placeholder="尾款支付提醒短信将发至此号码"
                    placeholderTextColor="#999"
                    keyboardType="phone-pad"
                  />
                </View>
              )}

              {/* 收货地址 */}
              <TouchableOpacity style={styles.addressRow} onPress={selectAddress}>
                {address ? (
                  <View style={styles.addressInfo}>
                    <Text style={styles.addressName}>
                      {address.contactName} {address.contactNo}
                    </Text>
                    <Text style={styles.addressDetail}>
                      {address.province}{address.city}{address.district}{address.address}
                    </Text>
                  </View>
                ) : (
                  <Text style={styles.noAddress}>
                    <Text style={styles.required}>*</Text> 请填写收货地址
                  </Text>
                )}
                <Text style={styles.arrow}>›</Text>
              </TouchableOpacity>

              {/* 协议 */}
              <View style={styles.agreementRow}>
                <Text style={styles.agreementText}>同意《平台服务协议》详情</Text>
                <Switch value={checked} onValueChange={setChecked} />
              </View>
            </ScrollView>

            {/* 支付按钮 */}
            <TouchableOpacity
              style={[styles.payBtn, submitting && styles.payBtnDisabled]}
              onPress={handlePay}
              disabled={submitting}
            >
              <Text style={styles.payBtnText}>
                ¥{lastPrice} 立即支付
              </Text>
            </TouchableOpacity>
          </View>
        </View>
      </Modal>
    );
  }
);

const styles = StyleSheet.create({
  overlay: {
    flex: 1,
    justifyContent: 'flex-end',
  },
  mask: {
    ...StyleSheet.absoluteFillObject,
    backgroundColor: 'rgba(0,0,0,0.5)',
  },
  content: {
    backgroundColor: '#fff',
    borderTopLeftRadius: 15,
    borderTopRightRadius: 15,
    maxHeight: '80%',
  },
  header: {
    flexDirection: 'row',
    justifyContent: 'center',
    alignItems: 'center',
    paddingVertical: 15,
    borderBottomWidth: 1,
    borderBottomColor: '#eee',
  },
  title: {
    fontSize: 16,
    fontWeight: '600',
    color: '#333',
  },
  closeBtn: {
    position: 'absolute',
    right: 15,
    fontSize: 28,
    color: '#999',
  },
  scrollContent: {
    paddingHorizontal: 15,
  },
  goodsInfo: {
    flexDirection: 'row',
    paddingVertical: 15,
    borderBottomWidth: 1,
    borderBottomColor: '#eee',
  },
  goodsImage: {
    width: 90,
    height: 90,
    borderRadius: 8,
    backgroundColor: '#f5f5f5',
  },
  goodsDetail: {
    flex: 1,
    marginLeft: 12,
    justifyContent: 'space-between',
  },
  goodsName: {
    fontSize: 14,
    color: '#333',
    lineHeight: 20,
  },
  priceRow: {
    flexDirection: 'row',
    alignItems: 'center',
  },
  price: {
    fontSize: 18,
    fontWeight: 'bold',
    color: '#ff6b00',
  },
  deposit: {
    fontSize: 12,
    color: '#8b3dff',
    marginLeft: 10,
    backgroundColor: 'rgba(139,61,255,0.1)',
    paddingHorizontal: 8,
    paddingVertical: 2,
    borderRadius: 10,
  },
  quantityRow: {
    flexDirection: 'row',
    alignItems: 'center',
  },
  qtyBtn: {
    width: 28,
    height: 28,
    borderRadius: 14,
    backgroundColor: '#f5f5f5',
    justifyContent: 'center',
    alignItems: 'center',
  },
  qtyBtnDisabled: {
    opacity: 0.3,
  },
  qtyBtnText: {
    fontSize: 18,
    color: '#333',
  },
  qtyNum: {
    fontSize: 16,
    color: '#333',
    marginHorizontal: 15,
  },
  row: {
    flexDirection: 'row',
    justifyContent: 'space-between',
    alignItems: 'center',
    paddingVertical: 15,
    borderBottomWidth: 1,
    borderBottomColor: '#eee',
  },
  rowLabel: {
    fontSize: 14,
    color: '#333',
  },
  rowValue: {
    fontSize: 14,
    color: '#ff6b00',
  },
  balance: {
    color: '#ff6b00',
  },
  payTypeSection: {
    paddingVertical: 10,
    borderBottomWidth: 1,
    borderBottomColor: '#eee',
  },
  payTypeItem: {
    flexDirection: 'row',
    justifyContent: 'space-between',
    alignItems: 'center',
    paddingVertical: 10,
  },
  payTypeName: {
    fontSize: 14,
    color: '#333',
  },
  radio: {
    width: 20,
    height: 20,
    borderRadius: 10,
    borderWidth: 2,
    borderColor: '#ddd',
  },
  radioActive: {
    borderColor: '#ff6b00',
    backgroundColor: '#ff6b00',
  },
  phoneRow: {
    paddingVertical: 15,
    borderBottomWidth: 1,
    borderBottomColor: '#eee',
  },
  phoneLabel: {
    fontSize: 14,
    color: '#333',
    marginBottom: 10,
  },
  required: {
    color: '#dd524d',
  },
  phoneInput: {
    height: 40,
    backgroundColor: '#f5f5f5',
    borderRadius: 8,
    paddingHorizontal: 12,
    fontSize: 14,
  },
  addressRow: {
    flexDirection: 'row',
    justifyContent: 'space-between',
    alignItems: 'center',
    paddingVertical: 15,
    borderBottomWidth: 1,
    borderBottomColor: '#eee',
  },
  addressInfo: {
    flex: 1,
  },
  addressName: {
    fontSize: 14,
    color: '#333',
    fontWeight: '500',
  },
  addressDetail: {
    fontSize: 12,
    color: '#666',
    marginTop: 4,
  },
  noAddress: {
    fontSize: 14,
    color: '#999',
  },
  arrow: {
    fontSize: 20,
    color: '#999',
    marginLeft: 10,
  },
  agreementRow: {
    flexDirection: 'row',
    justifyContent: 'space-between',
    alignItems: 'center',
    paddingVertical: 15,
  },
  agreementText: {
    fontSize: 14,
    color: '#666',
  },
  payBtn: {
    marginHorizontal: 15,
    marginTop: 15,
    height: 50,
    backgroundColor: '#ff6b00',
    borderRadius: 25,
    justifyContent: 'center',
    alignItems: 'center',
  },
  payBtnDisabled: {
    opacity: 0.6,
  },
  payBtnText: {
    color: '#fff',
    fontSize: 16,
    fontWeight: '600',
  },
});