import { CoreV1Api, Metrics } from "@kubernetes/client-node";

import getKubeConfig from "../../../utils/config/kubernetes";
import { parseCpu, parseMemory } from "../../../utils/kubernetes/kubernetes-utils";

export default async function handler(req, res) {
  const { type } = req.query;

  const kc = getKubeConfig();
  const coreApi = kc.makeApiClient(CoreV1Api);
  const metricsApi = new Metrics(kc);

  const nodes = await coreApi.listNode();
  const nodeCapacity = new Map();
  let cpuTotal = 0;
  let cpuUsage = 0;
  let memTotal = 0;
  let memUsage = 0;

  nodes.body.items.forEach((node) => {
    nodeCapacity.set(node.metadata.name, node.status.capacity);
    cpuTotal += Number.parseInt(node.status.capacity.cpu, 10);
    memTotal += parseMemory(node.status.capacity.memory);
  });

  const nodeMetrics = await metricsApi.getNodeMetrics();
  const nodeUsage = new Map();
  nodeMetrics.items.forEach((metrics) => {
    nodeUsage.set(metrics.metadata.name, metrics.usage);
    cpuUsage += parseCpu(metrics.usage.cpu);
    memUsage += parseMemory(metrics.usage.memory);
  });

  if (type === "cpu") {
    return res.status(200).json({
      cpu: {
        usage: (cpuUsage / cpuTotal) * 100,
        load: cpuUsage
      }
    });
  }
  // Maybe Storage CSI can provide this information
  // if (type === "disk") {
  //   if (!existsSync(target)) {
  //     return res.status(404).json({
  //       error: "Target not found",
  //     });
  //   }
  //
  //   return res.status(200).json({
  //     drive: await drive.info(target || "/"),
  //   });
  // }
  //
  if (type === "memory") {
    const SCALE_MB = 1024 * 1024;
    const usedMemMb = memUsage / SCALE_MB;
    const totalMemMb = memTotal / SCALE_MB;
    const freeMemMb = totalMemMb - usedMemMb;
    return res.status(200).json({
      memory: {
        usedMemMb,
        freeMemMb,
        totalMemMb
      }
    });
  }

  return res.status(400).json({
    error: "invalid type"
  });
}