import {
  getAuthString,
  getPageDom,
  getUrlParams,
  isClickModified,
} from "../libs/utils";
import { getAllComments, createSiblingLoader } from "../libs/dom-utils";
import { paths } from "../libs/paths";

const loaderCustomStyle = `
	height: 9px;
	margin-left: 5px;
`;

async function defaultButtons() {
  // Query all faveButtons that are, by default, present on the page
  // and have not been injected by this extension. This is achieved
  // by initialising this feature before `more-accessible-favorite`
  const faveButtonsList = document.querySelectorAll('a[href^="fave"]');

  for (const faveButton of faveButtonsList) {
    const auth = getUrlParams("auth", faveButton.href);
    const id = getUrlParams("id", faveButton.href);

    let unfave = faveButton.innerText === "un-favorite";
    let ongoingFavorite = false;

    faveButton.addEventListener("click", async (event) => {
      if (isClickModified(event)) {
        return;
      }

      event.preventDefault();

      if (ongoingFavorite) {
        return;
      }

      ongoingFavorite = true;

      const loader = createSiblingLoader(faveButton, loaderCustomStyle);
      await fetch(faveButton.href).then(() => loader.remove());

      unfave = !unfave;
      faveButton.innerHTML = unfave ? "un-favorite" : "favorite";
      faveButton.href = `fave?id=${id}&auth=${auth}${unfave ? "&un=t" : ""}`;

      ongoingFavorite = false;
    });
  }
}

async function commentButtons(metadata) {
  const items = getAllComments();

  for (const item of items) {
    const separatorPipe = document.createTextNode("| ");
    const faveButton = document.createElement("a");
    faveButton.innerText = "favorite";
    faveButton.classList.add("__rhn__fave-button");

    const headSpan = item.querySelector("span.comhead");
    const navsSpan = item.querySelector("span.navs");

    headSpan.insertBefore(separatorPipe, navsSpan);
    headSpan.insertBefore(faveButton, navsSpan);
  }

  let alreadyFaveItems = metadata.favorites;

  if (!alreadyFaveItems) {
    const page = await getPageDom(
      "https://news.ycombinator.com/favorites?comments=t&id=" + metadata.user
    );
    const fetchedPageItems = page.querySelectorAll(
      "table.itemlist > tbody > tr.athing"
    );
    alreadyFaveItems = [...fetchedPageItems].map((comm) => comm.id);
  }

  for (const item of items) {
    const { id } = item;
    const faveButton = item.querySelector(".__rhn__fave-button");
    faveButton.href = "javascript:void(0)";

    let unfave = false;

    if (alreadyFaveItems.includes(id)) {
      faveButton.innerHTML = "un-favorite";
      unfave = true;
    } else {
      faveButton.innerHTML = "favorite";
    }

    let ongoingFavorite = false;

    faveButton.addEventListener("click", async () => {
      if (ongoingFavorite) {
        return;
      }

      ongoingFavorite = true;

      const loader = createSiblingLoader(faveButton, loaderCustomStyle);

      const auth = await getAuthString(id);
      const url = `https://news.ycombinator.com/fave?id=${id}&auth=${auth}${
        unfave ? "&un=t" : ""
      }`;

      await fetch(url).then(() => loader.remove());

      unfave = !unfave;
      faveButton.innerHTML = unfave ? "un-favorite" : "favorite";

      ongoingFavorite = false;
    });
  }
}

async function storyButtons(metadata) {
  const items = document.querySelectorAll("td.subtext span.subline");

  for (const item of items) {
    const lastAnchorButton = item.lastElementChild;

    const separatorPipe = document.createTextNode(" | ");
    const faveButton = document.createElement("a");
    faveButton.innerText = "favorite";
    faveButton.classList.add("__rhn__fave-button");

    item.insertBefore(faveButton, lastAnchorButton);
    item.insertBefore(separatorPipe, lastAnchorButton);
  }

  let alreadyFaveItems = metadata.favorites;

  if (!alreadyFaveItems) {
    const page = await getPageDom(
      "https://news.ycombinator.com/favorites?id=" + metadata.user
    );
    const fetchedPageItems = page.querySelectorAll(
      "table.itemlist > tbody > tr.athing"
    );
    alreadyFaveItems = [...fetchedPageItems].map((story) => story.id);
  }

  for (const item of items) {
    const faveButton = item.querySelector(".__rhn__fave-button");

    const authStringElement =
      item.querySelector('a[href^="flag"]') ||
      item.querySelector('a[href^="hide"]');

    if (!authStringElement) {
      continue;
    }

    const authStringUrl = authStringElement.href.replace("?", "&");
    const auth = getUrlParams("auth", authStringUrl);
    const id = getUrlParams("id", authStringUrl);

    let unfave = false;

    if (alreadyFaveItems.includes(id)) {
      faveButton.href = `fave?id=${id}&auth=${auth}&un=t`;
      faveButton.innerHTML = "un-favorite";
      unfave = true;
    } else {
      faveButton.href = `fave?id=${id}&auth=${auth}`;
    }

    let ongoingFavorite = false;

    faveButton.addEventListener("click", async (event) => {
      event.preventDefault();

      if (ongoingFavorite) {
        return;
      }

      ongoingFavorite = true;

      const loader = createSiblingLoader(faveButton, loaderCustomStyle);
      await fetch(faveButton.href).then(() => loader.remove());

      unfave = !unfave;
      faveButton.innerHTML = unfave ? "un-favorite" : "favorite";
      faveButton.href = `fave?id=${id}&auth=${auth}${unfave ? "&un=t" : ""}`;

      ongoingFavorite = false;
    });
  }
}

async function init(metadata) {
  const { path } = metadata;

  await defaultButtons();

  if (paths.comments.includes(path)) {
    await commentButtons(metadata);
  } else if (paths.stories.includes(path)) {
    await storyButtons(metadata);
  }

  return true;
}

const details = {
  id: "more-accessible-favorite",
  pages: {
    include: [...paths.stories, ...paths.comments, "/favorites"],
    exclude: ["/jobs"],
  },
  loginRequired: true,
  init,
};

export default details;