"use strict";

// Public modules from npm
const puppeteer = require("puppeteer");

// Modules from file
const shared = require("./shared.js");
const constURLs = require("./constants/urls.js");
const selectors = require("./constants/css-selectors.js");
const { preparePage } = require("./puppeteer-helper.js");
const { isF95URL } = require("./urls-helper.js");

/**
 * @protected
 * Search the F95Zone portal to find possible conversations regarding the game you are looking for.
 * @param {puppeteer.Browser} browser Browser object used for navigation
 * @param {String} gamename Name of the game to search for
 * @returns {Promise<String[]>} List of URL of possible games  obtained from the preliminary research on the F95 portal
 */
module.exports.getSearchGameResults = async function (browser, gamename) {
  if (shared.debug) console.log("Searching " + gamename + " on F95Zone");

  let page = await preparePage(browser); // Set new isolated page
  await page.setCookie(...shared.cookies); // Set cookies to avoid login
  await page.goto(constURLs.F95_SEARCH_URL, {
    waitUntil: shared.WAIT_STATEMENT,
  }); // Go to the search form and wait for it

  // Explicitly wait for the required items to load
  await page.waitForSelector(selectors.SEARCH_FORM_TEXTBOX);
  await page.waitForSelector(selectors.TITLE_ONLY_CHECKBOX);
  await page.waitForSelector(selectors.SEARCH_BUTTON);

  await page.type(selectors.SEARCH_FORM_TEXTBOX, gamename); // Type the game we desire
  await page.click(selectors.TITLE_ONLY_CHECKBOX); // Select only the thread with the game in the titles
  await Promise.all([
    page.click(selectors.SEARCH_BUTTON), // Execute search
    page.waitForNavigation({
      waitUntil: shared.WAIT_STATEMENT,
    }), // Wait for page to load
  ]);

  // Select all conversation titles
  let resultsThread = await page.$$(selectors.SEARCH_THREADS_RESULTS_BODY);

  // For each element found extract the info about the conversation
  if (shared.debug) console.log("Extracting info from conversations");
  let results = [];
  for (let element of resultsThread) {
    let gameUrl = await getOnlyGameThreads(page, element);
    if (gameUrl !== null) results.push(gameUrl);
  }
  if (shared.debug) console.log("Find " + results.length + " conversations");
  await page.close(); // Close the page

  return results;
};

//#region Private methods
/**
 * @private
 * Return the link of a conversation if it is a game or a mod.
 * @param {puppeteer.Page} page Page containing the conversation to be analyzed
 * @param {puppeteer.ElementHandle} divHandle Element of the conversation to be analyzed
 * @return {Promise<String>} URL of the game/mod or null if the URL is not of a game
 */
async function getOnlyGameThreads(page, divHandle) {
  // Obtain the elements containing the basic information
  let titleHandle = await divHandle.$(selectors.THREAD_TITLE);
  let forumHandle = await divHandle.$(selectors.SEARCH_THREADS_MEMBERSHIP);

  // Get the forum where the thread was posted
  let forum = await getMembershipForum(page, forumHandle);
  if (forum !== "GAMES" && forum != "MODS") return null;

  // Get the URL of the thread from the title
  return await getThreadURL(page, titleHandle);
}

/**
 * @private
 * Obtain the membership forum of the thread passed throught "handle".
 * @param {puppeteer.Page} page Page containing the conversation to be analyzed
 * @param {puppeteer.ElementHandle} handle Handle containing the forum membership
 * @returns {Promise<String>} Uppercase membership category
 */
async function getMembershipForum(page, handle) {
  // The link can be something like:
  // + /forums/request.NUMBER/
  // + /forums/game-recommendations-identification.NUMBER/
  // + /forums/games.NUMBER/ <-- We need this

  let link = await page.evaluate(
    /* istanbul ignore next */
    (e) => e.getAttribute("href"),
    handle
  );

  // Parse link
  link = link.replace("/forums/", "");
  let endIndex = link.indexOf(".");
  let forum = link.substring(0, endIndex);

  return forum.toUpperCase();
}

/**
 * @private
 * Obtain the URL of the thread passed through "handle".
 * @param {puppeteer.Page} page Page containing the conversation to be analyzed
 * @param {puppeteer.ElementHandle} handle Handle containing the thread title
 * @returns {Promise<String>} URL of the thread
 */
async function getThreadURL(page, handle) {
  let relativeURLThread = await page.evaluate(
    /* istanbul ignore next */
    (e) => e.querySelector("a").href,
    handle
  );

  // Some game already have a full URL
  if (isF95URL(relativeURLThread)) return relativeURLThread;

  let urlThread = new URL(relativeURLThread, constURLs.F95_BASE_URL).toString();
  return urlThread;
}
//#endregion Private methods