import { useState, useCallback, useEffect } from 'react';
import {
  Button, Form, Input, InputNumber, message, Modal, Popconfirm, Result, Select, Space, Table, Tag,
} from 'antd';
import type { ColumnsType } from 'antd/es/table';

import {
  criticalValueThresholdApi,
  type CriticalValueThreshold,
  type CreateThresholdReq,
  type UpdateThresholdReq,
  INDICATOR_OPTIONS,
  DIRECTION_OPTIONS,
  LEVEL_OPTIONS,
  LEVEL_COLOR,
  INDICATOR_LABEL,
  DIRECTION_LABEL,
  LEVEL_LABEL,
} from '../../api/health/criticalValueThresholds';
import { PageContainer } from '../../components/PageContainer';
import { usePermission } from '../../hooks/usePermission';

export default function CriticalValueThresholdList() {
  const { hasPermission } = usePermission('health.critical-value-thresholds.list');

  const [data, setData] = useState<CriticalValueThreshold[]>([]);
  const [loading, setLoading] = useState(false);
  const [loaded, setLoaded] = useState(false);

  const [modalOpen, setModalOpen] = useState(false);
  const [editRecord, setEditRecord] = useState<CriticalValueThreshold | null>(null);
  const [submitting, setSubmitting] = useState(false);
  const [form] = Form.useForm();

  const fetchData = useCallback(async () => {
    setLoading(true);
    try {
      const list = await criticalValueThresholdApi.list();
      setData(list);
      setLoaded(true);
    } catch {
      message.error('加载危急值阈值失败');
    } finally {
      setLoading(false);
    }
  }, []);

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

  const handleCreate = () => {
    setEditRecord(null);
    form.resetFields();
    form.setFieldsValue({ level: 'critical' });
    setModalOpen(true);
  };

  const handleEdit = (record: CriticalValueThreshold) => {
    setEditRecord(record);
    form.setFieldsValue({
      indicator: record.indicator,
      direction: record.direction,
      threshold_value: record.threshold_value,
      level: record.level,
      department: record.department,
      age_min: record.age_min,
      age_max: record.age_max,
    });
    setModalOpen(true);
  };

  const handleSubmit = async () => {
    try {
      const values = await form.validateFields();
      setSubmitting(true);

      if (editRecord) {
        const req: UpdateThresholdReq = {
          threshold_value: values.threshold_value,
          level: values.level,
          department: values.department,
          age_min: values.age_min,
          age_max: values.age_max,
          version: editRecord.version,
        };
        await criticalValueThresholdApi.update(editRecord.id, req);
        message.success('阈值已更新');
      } else {
        const req: CreateThresholdReq = values;
        await criticalValueThresholdApi.create(req);
        message.success('阈值已创建');
      }

      setModalOpen(false);
      fetchData();
    } catch {
      // validation
    } finally {
      setSubmitting(false);
    }
  };

  const handleDelete = async (record: CriticalValueThreshold) => {
    try {
      await criticalValueThresholdApi.delete(record.id);
      message.success('阈值已删除');
      fetchData();
    } catch {
      message.error('删除失败');
    }
  };

  const columns: ColumnsType<CriticalValueThreshold> = [
    {
      title: '指标',
      dataIndex: 'indicator',
      width: 120,
      render: (v: string) => INDICATOR_LABEL[v] ?? v,
    },
    {
      title: '方向',
      dataIndex: 'direction',
      width: 80,
      render: (v: string) => DIRECTION_LABEL[v] ?? v,
    },
    {
      title: '阈值',
      dataIndex: 'threshold_value',
      width: 100,
      render: (v: number) => v,
    },
    {
      title: '级别',
      dataIndex: 'level',
      width: 80,
      render: (v: string) => (
        <Tag color={LEVEL_COLOR[v] ?? 'default'}>{LEVEL_LABEL[v] ?? v}</Tag>
      ),
    },
    {
      title: '科室',
      dataIndex: 'department',
      width: 100,
      render: (v: string) => v ?? '通用',
    },
    {
      title: '年龄范围',
      width: 120,
      render: (_, record) => {
        if (record.age_min == null && record.age_max == null) return '不限';
        return `${record.age_min ?? 0} - ${record.age_max ?? '∞'}`;
      },
    },
    {
      title: '状态',
      dataIndex: 'is_active',
      width: 80,
      render: (v: boolean) => <Tag color={v ? 'green' : 'default'}>{v ? '启用' : '停用'}</Tag>,
    },
    {
      title: '操作',
      width: 140,
      render: (_, record) => (
        <Space>
          <Button size="small" onClick={() => handleEdit(record)}>编辑</Button>
          <Popconfirm title="确定删除此阈值规则？" onConfirm={() => handleDelete(record)}>
            <Button size="small" danger>删除</Button>
          </Popconfirm>
        </Space>
      ),
    },
  ];

  if (!hasPermission) {
    return <Result status="403" title="权限不足" subTitle="您没有查看危急值阈值的权限" />;
  }

  return (
    <PageContainer
      title="危急值阈值"
      actions={<Button type="primary" onClick={handleCreate}>添加阈值</Button>}
    >
      <Space style={{ marginBottom: 16 }}>
        <Button type="primary" onClick={fetchData} loading={loading}>
          {loaded ? '刷新' : '加载阈值'}
        </Button>
      </Space>

      {loaded && (
        <Table<CriticalValueThreshold>
          rowKey="id"
          columns={columns}
          dataSource={data}
          loading={loading}
          pagination={false}
        />
      )}

      <Modal
        title={editRecord ? '编辑阈值' : '添加阈值'}
        open={modalOpen}
        onOk={handleSubmit}
        onCancel={() => setModalOpen(false)}
        confirmLoading={submitting}
        width={520}
      >
        <Form form={form} layout="vertical">
          {!editRecord && (
            <>
              <Form.Item name="indicator" label="指标" rules={[{ required: true, message: '请选择指标' }]}>
                <Select options={INDICATOR_OPTIONS} placeholder="选择指标" />
              </Form.Item>
              <Form.Item name="direction" label="方向" rules={[{ required: true, message: '请选择方向' }]}>
                <Select options={DIRECTION_OPTIONS} placeholder="偏高/偏低" />
              </Form.Item>
            </>
          )}
          <Form.Item name="threshold_value" label="阈值" rules={[{ required: true, message: '请输入阈值' }]}>
            <InputNumber style={{ width: '100%' }} step={0.1} />
          </Form.Item>
          <Form.Item name="level" label="级别">
            <Select options={LEVEL_OPTIONS} />
          </Form.Item>
          <Form.Item name="department" label="限定科室">
            <Input placeholder="留空表示通用规则" />
          </Form.Item>
          <Space style={{ width: '100%' }} size="middle">
            <Form.Item name="age_min" label="最小年龄">
              <InputNumber min={0} max={150} placeholder="不限" style={{ width: 200 }} />
            </Form.Item>
            <Form.Item name="age_max" label="最大年龄">
              <InputNumber min={0} max={150} placeholder="不限" style={{ width: 200 }} />
            </Form.Item>
          </Space>
        </Form>
      </Modal>
    </PageContainer>
  );
}
