contentScript.js

const wikipediaPageCache = new Map()

function checkWikipediaPage(twitterHandle) {
  const cached = wikipediaPageCache.get(twitterHandle)
  if (cached) return Promise.resolve(cached)

  const safeTwitterHandle = encodeURIComponent(twitterHandle)

  const apiUrl = `https://hub.toolforge.org/P2002:${safeTwitterHandle}?format=json&lang=en,sv,auto`

  const promise = fetch(apiUrl)
    .then((response) =>
      response.ok ? response.json() : Promise.resolve(false)
    )
    .then((data) => {
      const destination = data.destination
      const url = destination?.url
      const title = destination?.preferedSitelink?.title
      return { url, title }
    })
    .catch((error) => {
      console.error("Error fetching Wikidata:", error)
      return false
    })
  wikipediaPageCache.set(twitterHandle, promise)
  return promise
}

const observerOptions = {
  root: null,
  rootMargin: "100px",
  threshold: 0.1,
}

const profileLinkObserver = new IntersectionObserver((entries, observer) => {
  entries.forEach((entry) => {
    if (entry.isIntersecting) {
      const profileLink = entry.target
      const twitterHandle = profileLink.getAttribute("href").replace("/", "")
      if (
        !profileLink.textContent ||
        twitterHandle.includes("/") ||
        twitterHandle.includes("?")
      ) {
        return
      }
      checkWikipediaPage(twitterHandle).then(({ url, title }) => {
        if (url) {
          const icon = document.createElement("img")
          icon.src = chrome.runtime.getURL("icon.svg")
          icon.style.width = "16px"
          icon.style.height = "16px"
          icon.style.margin = "2px 4px"
          if (!title.startsWith(profileLink.textContent)) {
            icon.style.opacity = "0.5"
          }
          icon.style.verticalAlign = "text-bottom"
          icon.title = `This account has a Wikipedia-page called ${title}.`

          const link = document.createElement("a")
          link.href = url
          link.appendChild(icon)

          const wrapper = document.createElement("span")
          wrapper.style.display = "flex"

          profileLink.parentNode.insertBefore(wrapper, profileLink)
          wrapper.appendChild(profileLink)
          wrapper.insertAdjacentElement("beforeend", link)

          profileLink.setAttribute("data-wikipedia-icon-added", "true")
        }
      })

      observer.unobserve(profileLink)
    }
  })
}, observerOptions)

function observeProfileLink(profileLink) {
  profileLinkObserver.observe(profileLink)
}

function addWikipediaIconToProfile() {
  const profileLinks = Array.from(
    document.querySelectorAll(
      '[data-testid="primaryColumn"] div[dir="auto"] a[href^="/"]:not([data-wikipedia-icon-added]), [data-testid="primaryColumn"] a[href^="/"][role="link"]:not([data-wikipedia-icon-added])'
    )
  ).filter((el) => !el.textContent.includes("@"))

  profileLinks.forEach((profileLink) => {
    profileLink.setAttribute("data-wikipedia-icon-added", "true")
    observeProfileLink(profileLink)
  })
}

const observer = new MutationObserver((mutations) => {
  mutations.forEach((mutation) => {
    if (mutation.type === "childList") {
      addWikipediaIconToProfile()
    }
  })
})

observer.observe(document.body, { childList: true, subtree: true })

addWikipediaIconToProfile()