'use strict';

// Public modules from npm
const puppeteer = require('puppeteer'); // skipcq: JS-0128

// 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');

  const 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
  const 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');
  const results = [];
  for (const element of resultsThread) {
    const 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
  const titleHandle = await divHandle.$(selectors.THREAD_TITLE);
  const forumHandle = await divHandle.$(selectors.SEARCH_THREADS_MEMBERSHIP);

  // Get the forum where the thread was posted
  const 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/', '');
  const endIndex = link.indexOf('.');
  const 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) {
  const 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;

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