const { findSellerByDomain } = require("../db/seller.db")
const { getSellerById, getSellerIdByDomain } = require("./redis/sellerCache.service")

function normalizeDomain(hostname) {
  return hostname.replace(/^www\./, "")
}

async function findSellerFromLink(url) {
  let hostname

  try {
    hostname = new URL(url).hostname
  } catch {
    return null
  }

  const domain = normalizeDomain(hostname)

  const cachedSellerId = await getSellerIdByDomain(domain)
  if (cachedSellerId) {
    const cachedSeller = await getSellerById(cachedSellerId)
    if (cachedSeller) return cachedSeller
  }

  const seller = await findSellerByDomain(domain)
  if (seller) return seller

  const domainParts = domain.split(".")
  for (let i = 1; i <= domainParts.length - 2; i += 1) {
    const parentDomain = domainParts.slice(i).join(".")
    const cachedParentId = await getSellerIdByDomain(parentDomain)
    if (cachedParentId) {
      const cachedParent = await getSellerById(cachedParentId)
      if (cachedParent) return cachedParent
    }

    const parentSeller = await findSellerByDomain(parentDomain)
    if (parentSeller) return parentSeller
  }

  return null
}

module.exports = {
  findSellerFromLink,
}