import { useEffect, useState } from 'react';
import { useNavigate } from 'react-router-dom';
import { deleteDiscount, fetchDiscounts, upsertDiscount } from '../api';
import type { Discount } from '../types';
import './Discounts.css';

export function Discounts() {
  const [list, setList] = useState<Discount[]>([]);
  const [domain, setDomain] = useState('');
  const [discount, setDiscount] = useState('');
  const [note, setNote] = useState('');
  const [editing, setEditing] = useState<Discount | null>(null);
  const [error, setError] = useState('');
  const navigate = useNavigate();

  const load = () => fetchDiscounts().then(setList).catch(() => {});

  useEffect(() => { load(); }, []);

  const handleSubmit = async (e: React.FormEvent) => {
    e.preventDefault();
    setError('');
    const d = parseFloat(discount);
    if (isNaN(d) || d <= 0 || d > 1) {
      setError('折扣系数需在 0~1 之间，如 0.8 表示八折');
      return;
    }
    try {
      await upsertDiscount(domain.trim(), d, note.trim() || undefined);
      setDomain(''); setDiscount(''); setNote(''); setEditing(null);
      load();
    } catch (err: any) {
      setError(err.message);
    }
  };

  const startEdit = (item: Discount) => {
    setEditing(item);
    setDomain(item.domain);
    setDiscount(String(item.discount));
    setNote(item.note ?? '');
  };

  const handleDelete = async (id: number) => {
    await deleteDiscount(id);
    load();
  };

  return (
    <div className="discounts-page">
      <header className="discounts-header">
        <span className="discounts-title">折扣管理</span>
      </header>

      <form className="discount-form" onSubmit={handleSubmit}>
        <input
          className="discount-input"
          placeholder="域名，如 aigc.wangxunai.com"
          value={domain}
          onChange={e => setDomain(e.target.value)}
          required
        />
        <input
          className="discount-input discount-input--short"
          placeholder="折扣系数，如 0.8"
          value={discount}
          onChange={e => setDiscount(e.target.value)}
          required
        />
        <input
          className="discount-input"
          placeholder="备注（可选）"
          value={note}
          onChange={e => setNote(e.target.value)}
        />
        <button className="discount-btn discount-btn--primary" type="submit">
          {editing ? '保存' : '添加'}
        </button>
        {editing && (
          <button className="discount-btn" type="button" onClick={() => {
            setEditing(null); setDomain(''); setDiscount(''); setNote('');
          }}>取消</button>
        )}
      </form>
      {error && <div className="discount-error">{error}</div>}

      <div className="discount-table-wrap">
        <table className="discount-table">
          <thead>
            <tr>
              <th>域名</th>
              <th>折扣系数</th>
              <th>折扣</th>
              <th>备注</th>
              <th>更新时间</th>
              <th>操作</th>
            </tr>
          </thead>
          <tbody>
            {list.map(item => (
              <tr key={item.id}>
                <td className="td-domain">
                    <button
                      className="td-domain-link"
                      onClick={() => navigate(`/discounts/${encodeURIComponent(item.domain)}/model-prices`)}
                    >
                      {item.domain}
                    </button>
                  </td>
                <td className="td-discount">{item.discount}</td>
                <td className="td-discount">{Math.round(item.discount * 10)}折</td>
                <td className="td-note">{item.note ?? '—'}</td>
                <td className="td-time">{new Date(item.updated_at).toLocaleString()}</td>
                <td className="td-actions">
                    <button className="discount-btn discount-btn--sm discount-btn--config" onClick={() => navigate(`/discounts/${encodeURIComponent(item.domain)}/model-prices`)}>模型价格</button>
                    <button className="discount-btn discount-btn--sm" onClick={() => startEdit(item)}>编辑</button>
                    <button className="discount-btn discount-btn--sm discount-btn--danger" onClick={() => handleDelete(item.id)}>删除</button>
                  </td>
              </tr>
            ))}
          </tbody>
        </table>
        {list.length === 0 && <div className="empty-msg">暂无折扣配置，所有域名按原价返回</div>}
      </div>
    </div>
  );
}