asb_cloud_front/src/pages/Deposit.jsx

import { Map, Overlay } from "pigeon-maps"
import pointer from '../images/pointer.svg'
import {Link} from "react-router-dom";
import LoaderPortal from '../components/LoaderPortal'
import { useState, useEffect } from "react";
import {ClusterService} from '../services/api'

const calcViewParams = (clusters) => {
  if (clusters.length === 0)
    return {center:[60.81226, 70.0562], zoom: 5}

  const center = clusters.reduce((sum, cluster) => {
    sum[0] += (cluster.latitude / clusters.length)
    sum[1] += (cluster.longitude / clusters.length)
    return sum
  }, [0, 0])

  const maxDeg = clusters.reduce((max, cluster) => {
    const dLatitude = Math.abs(center[0] - cluster.latitude)
    const dLongitude = Math.abs(center[1] - cluster.longitude)
    const d = dLatitude > dLongitude ? dLatitude : dLongitude
    return d > max ? d : max
  }, 0)

  return {center, zoom: maxDeg*25}
}

export default function Deposit() {
  const [clustersData, setClustersData] = useState([])
  const [showLoader, setShowLoader] = useState(false)

  const updateClusters = async()=>{
    setShowLoader(true) 
    try{
      const data = await ClusterService.getClusters()
      setClustersData(data)
    }catch{
      //ignore
    }    
    setShowLoader(false) 
  }

  useEffect(()=>{updateClusters()}, [])

  const viewParams = calcViewParams(clustersData)

  return (
    <LoaderPortal show={showLoader}>
      <Map 
        height='100vh'
        center={viewParams.center}
        zoom={viewParams.zoom}
        >
        {clustersData.map(cluster =>
          <Overlay  
            width={32} 
            anchor={[cluster.latitude, cluster.longitude]} 
            key={`${cluster.latitude}  ${cluster.longitude}`}
            >
              <Link to={`/cluster/${cluster.id}`}>
                <img width={40} src={pointer} alt="+"/>
                <span>{cluster.name}</span>
              </Link>
              
          </Overlay >)}
      </Map>
    </LoaderPortal>
  );
}