import React, { useState, useEffect } from 'react';
import { Table, Button, Modal, Form, Input, Select, Tag, Space, Message, Typography } from '@arco-design/web-react';

const { TextArea } = Input;
const { Title } = Typography;

interface Requirement {
  id: string;
  title: string;
  description?: string;
  priority: 'must' | 'should' | 'could' | 'wont';
  category: string;
  status: string;
  source?: string;
}

const PRIORITY_COLOR: Record<string, string> = { must: 'red', should: 'orange', could: 'blue', wont: 'grey' };
const PRIORITY_LABEL: Record<string, string> = { must: 'Must', should: 'Should', could: 'Could', wont: "Won't" };

export default function RequirementPage() {
  const [projectId] = useState('pmp-demo');
  const [data, setData] = useState<Requirement[]>([]);
  const [loading, setLoading] = useState(false);
  const [modalVisible, setModalVisible] = useState(false);
  const [form] = Form.useForm();

  const api = (path: string, opts?: RequestInit) => fetch(`/api/projects/${projectId}${path}`, opts);

  const fetchData = async () => {
    setLoading(true);
    try {
      const res = await api('/requirements');
      if (res.ok) { const d = await res.json(); setData(d?.requirements || (Array.isArray(d) ? d : [])) };
    } catch { Message.error('获取需求失败'); }
    setLoading(false);
  };

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

  const handleAdd = async () => {
    const values = form.getFieldsValue();
    try {
      const res = await api('/requirements', { method: 'POST', headers: { 'Content-Type': 'application/json' }, body: JSON.stringify(values) });
      if (res.ok) { Message.success('添加成功'); setModalVisible(false); form.resetFields(); fetchData(); }
      else Message.error('添加失败');
    } catch { Message.error('添加失败'); }
  };

  const handleCoverage = async () => {
    try {
      const res = await api('/requirements/coverage');
      if (res.ok) { const d = await res.json(); Modal.info({ title: '需求覆盖率', content: JSON.stringify(d, null, 2) }); }
    } catch { Message.error('获取覆盖率失败'); }
  };

  const handleConflict = async () => {
    try {
      const res = await api('/requirements/detect-conflicts', { method: 'POST' });
      if (res.ok) { const d = await res.json(); Modal.info({ title: '冲突检测结果', content: JSON.stringify(d, null, 2) }); }
    } catch { Message.error('冲突检测失败'); }
  };

  const columns = [
    { title: '标题', dataIndex: 'title' },
    { title: '优先级', dataIndex: 'priority', render: (v: string) => <Tag color={PRIORITY_COLOR[v]}>{PRIORITY_LABEL[v]}</Tag> },
    { title: '分类', dataIndex: 'category' },
    { title: '状态', dataIndex: 'status' },
    { title: '来源', dataIndex: 'source' },
  ];

  return (
    <div style={{ padding: 20 }}>
      <Title heading={4}>需求池管理</Title>
      <Space style={{ marginBottom: 16 }}>
        <Button type="primary" onClick={() => setModalVisible(true)}>添加需求</Button>
        <Button onClick={handleCoverage}>覆盖率</Button>
        <Button onClick={handleConflict}>冲突检测</Button>
      </Space>
      <Table rowKey="id" columns={columns} data={data} loading={loading} />
      <Modal title="添加需求" visible={modalVisible} onOk={handleAdd} onCancel={() => setModalVisible(false)}>
        <Form form={form} layout="vertical">
          <Form.Item label="标题" field="title" rules={[{ required: true }]}><Input /></Form.Item>
          <Form.Item label="描述" field="description"><TextArea /></Form.Item>
          <Form.Item label="优先级" field="priority" rules={[{ required: true }]}>
            <Select options={['must', 'should', 'could', 'wont'].map(v => ({ label: PRIORITY_LABEL[v], value: v }))} />
          </Form.Item>
          <Form.Item label="分类" field="category">
            <Select options={['功能', '性能', '安全', '体验', '其他'].map(v => ({ label: v, value: v }))} />
          </Form.Item>
        </Form>
      </Modal>
    </div>
  );
}