const FEED_URL = "https://jobs.appone.com/api/portal/v1/companyjobposts/seahaven";
const PORTAL_URL = "https://jobs.appone.com/seahaven";
const ALLOWED_HOSTS = new Set(["apply.appone.com", "jobs.appone.com"]);

function isAllowedJobUrl(value) {
  if (typeof value !== "string") return false;
  try {
    const url = new URL(value);
    return url.protocol === "https:" && ALLOWED_HOSTS.has(url.hostname);
  } catch {
    return false;
  }
}

function titleCase(value) {
  return value
    .replace(/[_-]+/g, " ")
    .toLowerCase()
    .replace(/\b\w/g, (char) => char.toUpperCase());
}

function formatSalary(salary) {
  if (!salary || salary.salaryOption !== "RANGE" || salary.periodType !== "YEAR") {
    return null;
  }
  const { minimum, maximum } = salary;
  if (!Number.isFinite(minimum) || !Number.isFinite(maximum)) return null;
  const money = new Intl.NumberFormat("en-US", {
    style: "currency",
    currency: "USD",
    maximumFractionDigits: 0,
  });
  return `${money.format(minimum)}\u2013${money.format(maximum)} per year`;
}

function normalizePost(post) {
  if (!post || typeof post !== "object") {
    throw new Error("Paychex job feed returned a posting that is not an object");
  }
  const title = typeof post.jobTitle === "string" ? post.jobTitle.trim() : "";
  if (!title) {
    throw new Error("Paychex job feed returned a posting without a title");
  }
  if (!isAllowedJobUrl(post.jobPostUrl)) {
    throw new Error(`Paychex job feed returned an unexpected apply URL for "${title}"`);
  }
  return {
    title,
    url: post.jobPostUrl,
    location: typeof post.location === "string" ? post.location.trim() : "",
    jobType: typeof post.jobType === "string" ? post.jobType.trim() : "",
    workplaceType: typeof post.workplaceType === "string" && post.workplaceType.trim()
      ? titleCase(post.workplaceType.trim())
      : "",
    salary: formatSalary(post.salary),
  };
}

module.exports = async function () {
  const response = await fetch(FEED_URL, {
    headers: {
      Accept: "application/json",
      "x-payx-bizpn": "Load Company Job Portal",
    },
    signal: AbortSignal.timeout(15000),
  });
  if (!response.ok) {
    throw new Error(`Paychex job feed request failed (${response.status})`);
  }

  const data = await response.json();
  if (!data || !Array.isArray(data.jobPosts)) {
    throw new Error("Paychex job feed is missing jobPosts");
  }

  return {
    portalUrl: PORTAL_URL,
    posts: data.jobPosts.map(normalizePost),
  };
};