import React, { type CSSProperties } from 'react';
import { Card, Col, Row } from 'antd';
import { useIntersectionObserver } from 'usehooks-ts';
import ReactECharts from '../../components/ECharts';
import type { ClassroomOccupancy, GanttRoom } from './Dashboard.types';
import { buildClassroomHeatmapOption, buildGanttOption } from './DashboardCharts';

const useInViewport = (rootMargin = '200px') => {
  const { ref, isIntersecting } = useIntersectionObserver({
    rootMargin,
    freezeOnceVisible: true,
  });
  return { ref, inView: isIntersecting };
};

const LazySection: React.FC<{
  title: string;
  vp: { ref: (node?: Element | null) => void; inView: boolean };
  minHeight: number;
  style?: CSSProperties;
  children: React.ReactNode;
}> = ({ title, vp, minHeight, style, children }) => {
  return (
    <div ref={vp.ref} style={style}>
      {vp.inView ? (
        <Row gutter={[16, 16]}>
          <Col xs={24}>
            <Card title={title}>{children}</Card>
          </Col>
        </Row>
      ) : (
        <Card title={title} style={{ minHeight }}>
          <div style={{ textAlign: 'center', padding: 40, color: '#999' }}>加载中…</div>
        </Card>
      )}
    </div>
  );
};

export const ClassroomHeatmapCard: React.FC<{
  data: ClassroomOccupancy[];
  isMobile: boolean;
}> = ({ data, isMobile }) => {
  const vp = useInViewport('200px');
  return (
    <LazySection
      title="教室占用热力图"
      vp={vp}
      minHeight={isMobile ? 340 : 440}
      style={{ marginBottom: 24 }}
    >
      {data.length > 0 ? (
        <ReactECharts
          option={buildClassroomHeatmapOption(data)}
          style={{ width: '100%', height: isMobile ? 300 : 400 }}
        />
      ) : (
        <div style={{ textAlign: 'center', padding: 40, color: '#999' }}>暂无教室数据</div>
      )}
    </LazySection>
  );
};

export const GanttCard: React.FC<{ data: GanttRoom[]; isMobile: boolean }> = ({
  data,
  isMobile,
}) => {
  const vp = useInViewport('200px');
  return (
    <LazySection
      title="入住时间线（甘特图）"
      vp={vp}
      minHeight={isMobile ? 340 : 490}
    >
      {data.length > 0 ? (
        <ReactECharts
          option={buildGanttOption(data)}
          style={{ width: '100%', height: isMobile ? 300 : 450 }}
        />
      ) : (
        <div style={{ textAlign: 'center', padding: 40, color: '#999' }}>暂无入住数据</div>
      )}
    </LazySection>
  );
};
