import cache from "memory-cache";

import { formatApiCall } from "utils/proxy/api-helpers";
import { httpProxy } from "utils/proxy/http";
import getServiceWidget from "utils/config/service-helpers";
import createLogger from "utils/logger";

const proxyName = "homeboxProxyHandler";
const sessionTokenCacheKey = `${proxyName}__sessionToken`;
const logger = createLogger(proxyName);

async function login(widget, service) {
  logger.debug("Homebox is rejecting the request, logging in.");

  const loginUrl = new URL(`${widget.url}/api/v1/users/login`).toString();
  const loginBody = `username=${encodeURIComponent(widget.username)}&password=${encodeURIComponent(widget.password)}`;
  const loginParams = {
    method: "POST",
    headers: { "Content-Type": "application/x-www-form-urlencoded" },
    body: loginBody,
  };

  const [, , data] = await httpProxy(loginUrl, loginParams);

  try {
    const { token, expiresAt } = JSON.parse(data.toString());
    const expiresAtDate = new Date(expiresAt).getTime();
    cache.put(`${sessionTokenCacheKey}.${service}`, token, expiresAtDate - Date.now());
    return { token };
  } catch (e) {
    logger.error("Unable to login to Homebox API: %s", e);
  }

  return { token: false };
}

async function apiCall(widget, endpoint, service) {
  const key = `${sessionTokenCacheKey}.${service}`;
  const url = new URL(formatApiCall("{url}/api/v1/{endpoint}", { endpoint, ...widget }));
  const headers = {
    "Content-Type": "application/json",
    Authorization: `${cache.get(key)}`,
  };
  const params = { method: "GET", headers };

  let [status, contentType, data, responseHeaders] = await httpProxy(url, params);

  if (status === 401 || status === 403) {
    logger.debug("Homebox API rejected the request, attempting to obtain new access token");
    const { token } = await login(widget, service);
    headers.Authorization = `${token}`;

    // retry request with new token
    [status, contentType, data, responseHeaders] = await httpProxy(url, params);

    if (status !== 200) {
      logger.error("HTTP %d logging in to Homebox, data: %s", status, data);
      return { status, contentType, data: null, responseHeaders };
    }
  }

  if (status !== 200) {
    logger.error("HTTP %d getting data from Homebox, data: %s", status, data);
    return { status, contentType, data: null, responseHeaders };
  }

  return { status, contentType, data: JSON.parse(data.toString()), responseHeaders };
}

export default async function homeboxProxyHandler(req, res) {
  const { group, service } = req.query;

  if (!group || !service) {
    logger.debug("Invalid or missing service '%s' or group '%s'", service, group);
    return res.status(400).json({ error: "Invalid proxy service type" });
  }

  const widget = await getServiceWidget(group, service);
  if (!widget) {
    logger.debug("Invalid or missing widget for service '%s' in group '%s'", service, group);
    return res.status(400).json({ error: "Invalid proxy service type" });
  }

  if (!cache.get(`${sessionTokenCacheKey}.${service}`)) {
    await login(widget, service);
  }

  // Get stats for the main blocks
  const { data: groupStats } = await apiCall(widget, "groups/statistics", service);

  // Get group info for currency
  const { data: groupData } = await apiCall(widget, "groups", service);

  return res.status(200).send({
    items: groupStats?.totalItems,
    locations: groupStats?.totalLocations,
    labels: groupStats?.totalLabels,
    totalWithWarranty: groupStats?.totalWithWarranty,
    totalValue: groupStats?.totalItemPrice,
    users: groupStats?.totalUsers,
    currencyCode: groupData?.currency,
  });
}