import { useEffect, useMemo, useState, useRef } from 'react';

import type { ExamClient } from '../../data/mockData';
import { searchPhysicalExamAddItem, getAddItemCustomerInfo } from '../../api';
import { Button, Input } from '../ui';
import { cls } from '../../utils/cls';
import nozImage from '../../assets/image/noz.png';

interface AddonTag {
  title: string;
  type: 1 | 2 | 3 | 4; // 1: 热门(红), 2: 普通(灰), 3: 医生推荐(蓝), 4: 折扣信息
}

interface AddonItem {
  id?: string;
  name: string;
  paid?: boolean;
  tags?: AddonTag[];
  originalPrice?: string;
  currentPrice?: string;
}

interface ExamAddonPanelProps {
  client: ExamClient;
}

export const ExamAddonPanel = ({ client }: ExamAddonPanelProps) => {
  const [addonList, setAddonList] = useState<AddonItem[]>([]);
  // 防抖：内部输入值（用于显示）
  const [addonSearchInput, setAddonSearchInput] = useState('');
  // 防抖：实际用于 API 调用的值（延迟更新）
  const [debouncedAddonSearch, setDebouncedAddonSearch] = useState('');
  const debounceTimerRef = useRef<number | null>(null);
  const [addonLoading, setAddonLoading] = useState(false);
  const [addonError, setAddonError] = useState<string | null>(null);
  // 折扣比例（1 = 100%）
  const [discountRatio, setDiscountRatio] = useState<number>(1);
  // 渠道折扣列表
  const [channelDiscounts, setChannelDiscounts] = useState<
    { channel_id?: string | null; channel_name?: string | null; discount_rate?: number | null; discount_name?: string | null }[]
  >([]);
  // 下拉框状态
  const [isDiscountDropdownOpen, setIsDiscountDropdownOpen] = useState(false);
  const discountDropdownRef = useRef<HTMLDivElement>(null);
  // 结算方式：'self' 自费, 'account' 挂账
  const [paymentMethod, setPaymentMethod] = useState<'self' | 'account'>('self');
  const [isPaymentMethodDropdownOpen, setIsPaymentMethodDropdownOpen] = useState(false);
  const paymentMethodDropdownRef = useRef<HTMLDivElement>(null);
  // 挂账公司
  const [accountCompany, setAccountCompany] = useState<string>('圆和');
  const [isAccountCompanyDropdownOpen, setIsAccountCompanyDropdownOpen] = useState(false);
  const accountCompanyDropdownRef = useRef<HTMLDivElement>(null);

  // 点击外部关闭下拉框
  useEffect(() => {
    const handleClickOutside = (event: MouseEvent) => {
      if (discountDropdownRef.current && !discountDropdownRef.current.contains(event.target as Node)) {
        setIsDiscountDropdownOpen(false);
      }
      if (paymentMethodDropdownRef.current && !paymentMethodDropdownRef.current.contains(event.target as Node)) {
        setIsPaymentMethodDropdownOpen(false);
      }
      if (accountCompanyDropdownRef.current && !accountCompanyDropdownRef.current.contains(event.target as Node)) {
        setIsAccountCompanyDropdownOpen(false);
      }
    };

    if (isDiscountDropdownOpen || isPaymentMethodDropdownOpen || isAccountCompanyDropdownOpen) {
      document.addEventListener('mousedown', handleClickOutside);
    }

    return () => {
      document.removeEventListener('mousedown', handleClickOutside);
    };
  }, [isDiscountDropdownOpen, isPaymentMethodDropdownOpen, isAccountCompanyDropdownOpen]);

  // 获取体检加项客户信息（用于拿到渠道折扣等信息）
  useEffect(() => {
    const physical_exam_id = Number(client.id);
    if (!physical_exam_id) return;

    const fetchCustomerInfo = async () => {
      try {
        const res = await getAddItemCustomerInfo({ physical_exam_id });
        if (res.Status === 200 && res.Data?.listChannelDiscount && res.Data.listChannelDiscount.length > 0) {
          setChannelDiscounts(res.Data.listChannelDiscount);
          const rate = res.Data.listChannelDiscount[0]?.discount_rate;
          if (typeof rate === 'number' && rate > 0) {
            setDiscountRatio(rate);
          }
        } else {
          setChannelDiscounts([]);
        }
      } catch (err) {
        console.error('获取加项客户信息失败', err);
      }
    };

    fetchCustomerInfo();
  }, [client.id]);

  // 防抖：当输入值变化时，延迟 0.5 秒后更新 debouncedAddonSearch（用于 API 调用）
  useEffect(() => {
    if (debounceTimerRef.current) {
      window.clearTimeout(debounceTimerRef.current);
    }

    debounceTimerRef.current = window.setTimeout(() => {
      setDebouncedAddonSearch(addonSearchInput);
    }, 500);

    return () => {
      if (debounceTimerRef.current) {
        window.clearTimeout(debounceTimerRef.current);
      }
    };
  }, [addonSearchInput]);

  // 拉取加项列表
  useEffect(() => {
    const fetchList = async () => {
      setAddonLoading(true);
      setAddonError(null);
      try {
        const res = await searchPhysicalExamAddItem({
          discount_ratio: discountRatio || 1,
          item_name: debouncedAddonSearch.trim() || null,
        });
        if (res.Status === 200 && Array.isArray(res.Data)) {
          const list: AddonItem[] = res.Data.map((item) => ({
            id: item.item_id ? String(item.item_id) : `addon_${item.item_name}`,
            name: item.item_name || '',
            originalPrice:
              item.original_price !== undefined && item.original_price !== null
                ? Number(item.original_price).toFixed(2)
                : '0.00',
            currentPrice:
              item.actual_received_amount !== undefined && item.actual_received_amount !== null
                ? Number(item.actual_received_amount).toFixed(2)
                : item.original_price !== undefined && item.original_price !== null
                  ? Number(item.original_price).toFixed(2)
                  : '0.00',
            tags: [],
            paid: false,
          }));
          setAddonList(list);
        } else {
          setAddonError(res.Message || '获取加项列表失败');
          setAddonList([]);
        }
      } catch (err) {
        console.error('获取加项列表失败', err);
        setAddonError('获取加项列表失败，请稍后重试');
        setAddonList([]);
      } finally {
        setAddonLoading(false);
      }
    };
    fetchList();
  }, [debouncedAddonSearch, discountRatio]);

  const allAddons = useMemo(() => addonList, [addonList]);

  const [selectedIds, setSelectedIds] = useState<Set<string>>(new Set());

  const maxSelect = 15;
  const selectedCount = selectedIds.size;

  const filteredAddons = allAddons;

  const toggleSelect = (id: string) => {
    if (selectedIds.has(id)) {
      setSelectedIds(prev => {
        const next = new Set(prev);
        next.delete(id);
        return next;
      });
    } else {
      if (selectedCount < maxSelect) {
        setSelectedIds(prev => new Set(prev).add(id));
      }
    }
  };

  // 计算价格汇总
  const selectedItems = allAddons.filter(item => selectedIds.has(item.id || item.name));
  const totalOriginal = selectedItems.reduce((sum, item) => {
    return sum + parseFloat(item.originalPrice || item.currentPrice || '0');
  }, 0);
  const totalCurrent = selectedItems.reduce((sum, item) => {
    return sum + parseFloat(item.currentPrice || item.originalPrice || '0');
  }, 0);
  const discount = totalOriginal - totalCurrent;

  // 获取标签样式
  const getTagStyle = (tag: AddonTag) => {
    switch (tag.type) {
      case 1: // 热门
        return 'bg-[#FDF0F0] text-[#BC4845]';
      case 3: // 医生推荐
        return 'bg-[#ECF0FF] text-[#6A6AE5]';
      case 4: // 折扣信息
        return 'bg-[#4C5460] text-[#F1F2F5]';
      default: // 2: 普通
        return 'bg-[#F1F2F5] text-[#464E5B]';
    }
  };

  // 获取折扣信息文字（从 tags 中提取 type 4 的标签，或计算折扣）
  const getDiscountText = (item: AddonItem) => {
    const discountTag = item.tags?.find(t => t.type === 4);
    if (discountTag) return discountTag.title;

    const orig = parseFloat(item.originalPrice || '0');
    const curr = parseFloat(item.currentPrice || '0');
    if (orig > 0 && curr < orig) {
      const percent = Math.round((curr / orig) * 100);
      return `渠道 ${percent} 折`;
    }
    return '渠道价';
  };

  // 构建折扣选项列表
  const discountOptions = useMemo(() => {
    const options: Array<{ value: number; label: string }> = [
      { value: 1, label: '100%（无折扣）' },
    ];
    channelDiscounts.forEach((item) => {
      const rate = typeof item.discount_rate === 'number' && item.discount_rate > 0 ? item.discount_rate : 1;
      const percent = Math.round(rate * 100);
      const label = item.discount_name || `${percent}%`;
      options.push({ value: rate, label });
    });
    return options;
  }, [channelDiscounts]);

  // 获取当前选中的标签
  const currentDiscountLabel = useMemo(() => {
    const option = discountOptions.find(opt => opt.value === discountRatio);
    return option?.label || '100%（无折扣）';
  }, [discountRatio, discountOptions]);

  // 处理折扣选择
  const handleDiscountSelect = (value: number) => {
    setDiscountRatio(value);
    setIsDiscountDropdownOpen(false);
  };

  // 处理结算方式选择
  const handlePaymentMethodSelect = (value: 'self' | 'account') => {
    setPaymentMethod(value);
    setIsPaymentMethodDropdownOpen(false);
  };

  // 处理挂账公司选择
  const handleAccountCompanySelect = (value: string) => {
    setAccountCompany(value);
    setIsAccountCompanyDropdownOpen(false);
  };

  // 结算方式选项
  const paymentMethodOptions: Array<{ value: 'self' | 'account'; label: string }> = [
    { value: 'self', label: '自费' },
    { value: 'account', label: '挂账' },
  ];

  // 挂账公司选项（可以根据实际需求从接口获取）
  const accountCompanyOptions: Array<{ value: string; label: string }> = [
    { value: '圆和', label: '圆和' },
  ];

  return (
    <div className='space-y-4'>
      {/* 标题和说明 */}
      <div>
        <div className='flex items-center justify-between mb-3 gap-4'>
          <div className='flex items-center gap-2'>
            <h3 className='text-lg font-semibold text-gray-900 whitespace-nowrap'>体检套餐加项选择</h3>
            <div className='flex items-center gap-2 text-xs text-gray-600'>
              {/* <span className='whitespace-nowrap'>折扣比例</span> */}
              <div ref={discountDropdownRef} className='relative'>
                <button
                  type='button'
                  onClick={() => setIsDiscountDropdownOpen(!isDiscountDropdownOpen)}
                  className={cls(
                    'border-gray-300 rounded-lg px-3 py-1.5 text-xs text-gray-700 bg-white',
                    'focus:outline-none focus:ring-1 focus:ring-blue-500 focus:border-blue-500',
                    'min-w-[140px] flex items-center justify-between gap-2',
                    'hover:border-gray-400 transition-colors'
                  )}
                >
                  <span>{currentDiscountLabel}</span>
                  <span className={cls('text-gray-400 transition-transform text-[10px]', isDiscountDropdownOpen && 'rotate-180')}>
                    ▼
                  </span>
                </button>
                {isDiscountDropdownOpen && (
                  <div className='absolute z-50 w-full mt-1 bg-white border border-gray-300 rounded-lg shadow-lg overflow-hidden'>
                    {discountOptions.map((option) => (
                      <button
                        key={option.value}
                        type='button'
                        onClick={() => handleDiscountSelect(option.value)}
                        className={cls(
                          'w-full px-3 py-2 text-xs text-left transition-colors',
                          'hover:bg-gray-50',
                          discountRatio === option.value && 'bg-blue-50 text-blue-700 font-medium',
                          discountRatio !== option.value && 'text-gray-700'
                        )}
                      >
                        {option.label}
                      </button>
                    ))}
                  </div>
                )}
              </div>
            </div>
          </div>

          <div className='w-[260px] flex items-center gap-2'>
            <Input
              placeholder='搜索 加项名称'
              value={addonSearchInput}
              onChange={(e) => setAddonSearchInput(e.target.value)}
              className='text-sm flex-1'
            />
            {addonSearchInput && (
              <Button
                className='px-3 py-1.5 text-xs whitespace-nowrap'
                onClick={() => setAddonSearchInput('')}
              >
                重置
              </Button>
            )}
          </div>
        </div>
        {/* <div className='text-xs text-gray-600 space-y-1'>
          <div>最多可选 {maxSelect} 项 · 一排 5 个</div>
          <div>已勾选 {selectedCount} 项,自费加项费用按渠道折扣价结算。</div>
        </div> */}
      </div>

      {/* 加项网格 */}
      <div className='overflow-y-auto overflow-x-hidden max-h-[366px]'>
        <div className='grid grid-cols-5 gap-3 min-h-[142px]'>
          {addonError && (
            <div className='col-span-5 text-xs text-amber-600'>{addonError}</div>
          )}
          {addonLoading && (
            <div className='col-span-5 text-xs text-gray-500'>加载中...</div>
          )}
          {!addonLoading && !addonError && filteredAddons.length === 0 && (
            <div className='col-span-5 text-xs text-gray-500'>暂无数据</div>
          )}
          {filteredAddons.map((item) => {
            const id = item.id || item.name;
            const isSelected = selectedIds.has(id);
            const origPrice = parseFloat(item.originalPrice || '0');
            const currPrice = parseFloat(item.currentPrice || '0');

            return (
              <div
                key={id}
                className='border rounded-lg p-3 cursor-pointer transition-all flex flex-col relative'
                onClick={() => toggleSelect(id)}
              >
                {/* 无折扣标签图片 - 浮动在右上角 */}
                <img
                  src={nozImage}
                  alt='无折扣'
                  className='absolute top-[-10px] right-[-10px] w-12 h-12 object-contain pointer-events-none z-10'
                />

                {/* 第一行：复选框 + 名称 */}
                <div className='flex items-start gap-2 mb-1'>
                  <input
                    type='checkbox'
                    checked={isSelected}
                    onChange={() => toggleSelect(id)}
                    onClick={(e) => e.stopPropagation()}
                    className='mt-0.5 w-4 h-4 rounded border-gray-300 text-blue-600 focus:ring-blue-500'
                  />
                  <div className='flex-1 min-w-0'>
                    <div className='font-semibold text-[14px] text-gray-900'>{item.name}</div>
                  </div>
                </div>

                {/* 第二行：标签 */}
                {item.tags && item.tags.length >= 0 && (
                  <div className='flex flex-wrap gap-1 mb-1 pl-6'>
                    {item.tags
                      .filter(t => t.type !== 4) // 折扣信息单独显示
                      .map((tag, idx) => (
                        <span
                          key={idx}
                          className={`text-[10px] px-2 rounded-full ${getTagStyle(tag)}`}
                        >
                          {tag.title}
                        </span>
                      ))}
                  </div>
                )}

                {/* 第三行：价格信息（固定在卡片底部） */}
                <div className='mt-auto pt-1'>
                  <div className='flex flex-col'>
                    {origPrice >= 0 && origPrice >= currPrice && (
                      <span className='text-xs text-gray-400 line-through'>¥{origPrice.toFixed(0)}</span>
                    )}
                    <div className='flex items-center justify-between gap-2'>
                      <span className='text-[14px] font-bold text-red-600'>¥{currPrice.toFixed(0)}</span>
                      <span className={`text-[10px] px-2 rounded-full bg-[#EAFCF1] text-[#447955] whitespace-nowrap`}>
                        {getDiscountText(item)}
                      </span>
                    </div>
                  </div>
                </div>
              </div>
            );
          })}
        </div>
      </div>

      {/* 底部汇总和支付 */}
      <div className='border-t pt-4 mt-6 flex items-center justify-between'>
        <div className='space-y-1 text-sm'>
          <div className='text-gray-600'>
            加项原价合计: <span className='text-gray-900'>¥{totalOriginal.toFixed(0)}</span>
          </div>
          <div className='text-gray-600'>
            渠道折扣价: <span className='text-xl font-bold text-red-600'>¥{totalCurrent.toFixed(0)}</span>
            {discount > 0 && (
              <span className='text-gray-500 ml-1'>已优惠 ¥{discount.toFixed(0)}</span>
            )}
          </div>
          {/* <div className='text-xs text-gray-500'>结算方式: 个人支付 (微信 / 支付宝)</div> */}
        </div>
        <div className='flex items-center gap-3'>
          {/* 结算方式 */}
          <div className='flex items-center gap-2 text-xs text-gray-600'>
            <span className='whitespace-nowrap'>结算方式</span>
            <div ref={paymentMethodDropdownRef} className='relative'>
              <button
                type='button'
                onClick={() => setIsPaymentMethodDropdownOpen(!isPaymentMethodDropdownOpen)}
                className={cls(
                  'border border-gray-300 rounded-lg px-3 py-1.5 text-xs text-gray-700 bg-white',
                  'focus:outline-none focus:ring-1 focus:ring-blue-500 focus:border-blue-500',
                  'min-w-[100px] flex items-center justify-between gap-2',
                  'hover:border-gray-400 transition-colors'
                )}
              >
                <span>{paymentMethodOptions.find(opt => opt.value === paymentMethod)?.label || '自费'}</span>
                <span className={cls('text-gray-400 transition-transform text-[10px]', isPaymentMethodDropdownOpen && 'rotate-180')}>
                  ▼
                </span>
              </button>
              {isPaymentMethodDropdownOpen && (
                <div className='absolute z-50 w-full bottom-full mb-1 bg-white border border-gray-300 rounded-lg shadow-lg overflow-hidden'>
                  {paymentMethodOptions.map((option) => (
                    <button
                      key={option.value}
                      type='button'
                      onClick={() => handlePaymentMethodSelect(option.value)}
                      className={cls(
                        'w-full px-3 py-2 text-xs text-left transition-colors',
                        'hover:bg-gray-50',
                        paymentMethod === option.value && 'bg-blue-50 text-blue-700 font-medium',
                        paymentMethod !== option.value && 'text-gray-700'
                      )}
                    >
                      {option.label}
                    </button>
                  ))}
                </div>
              )}
            </div>
          </div>

          {/* 挂账公司 */}
          {paymentMethod === 'account' && (
            <div className='flex items-center gap-2 text-xs text-gray-600'>
              <span className='whitespace-nowrap'>挂账公司</span>
              <div ref={accountCompanyDropdownRef} className='relative'>
                <button
                  type='button'
                  onClick={() => setIsAccountCompanyDropdownOpen(!isAccountCompanyDropdownOpen)}
                  className={cls(
                    'border border-gray-300 rounded-lg px-3 py-1.5 text-xs text-gray-700 bg-white',
                    'focus:outline-none focus:ring-1 focus:ring-blue-500 focus:border-blue-500',
                    'min-w-[100px] flex items-center justify-between gap-2',
                    'hover:border-gray-400 transition-colors'
                  )}
                >
                  <span>{accountCompany}</span>
                  <span className={cls('text-gray-400 transition-transform text-[10px]', isAccountCompanyDropdownOpen && 'rotate-180')}>
                    ▼
                  </span>
                </button>
                {isAccountCompanyDropdownOpen && (
                  <div className='absolute z-50 w-full bottom-full mb-1 bg-white border border-gray-300 rounded-lg shadow-lg overflow-hidden'>
                    {accountCompanyOptions.map((option) => (
                      <button
                        key={option.value}
                        type='button'
                        onClick={() => handleAccountCompanySelect(option.value)}
                        className={cls(
                          'w-full px-3 py-2 text-xs text-left transition-colors',
                          'hover:bg-gray-50',
                          accountCompany === option.value && 'bg-blue-50 text-blue-700 font-medium',
                          accountCompany !== option.value && 'text-gray-700'
                        )}
                      >
                        {option.label}
                      </button>
                    ))}
                  </div>
                )}
              </div>
            </div>
          )}

          <Button
            className='bg-[#269745] hover:bg-[#269745]/80 rounded-3xl text-white px-6 py-3 text-base font-medium'
            disabled={selectedCount === 0}
          >
            确认支付 ¥{totalCurrent.toFixed(0)}
          </Button>
        </div>
      </div>
    </div>
  );
};