const allLinks = [...document.getElementsByTagName('a')];
const bodyInner = document.querySelector('.inner');
const tableElem = document.querySelector('table');
const infoRegex = /(-thumb)?\.(jpg|nfo|srt)$/;
let infoFiles = 0;
let infoFilesAccounted = 0;

const arrow = `
<svg version="1.1" id="back-arrow" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" x="0px" y="0px"
   viewBox="0 0 492 492" style="enable-background:new 0 0 492 492;" xml:space="preserve">
  <g>
    <g>
      <path fill="#fff" d="M464.344,207.418l0.768,0.168H135.888l103.496-103.724c5.068-5.064,7.848-11.924,7.848-19.124
        c0-7.2-2.78-14.012-7.848-19.088L223.28,49.538c-5.064-5.064-11.812-7.864-19.008-7.864c-7.2,0-13.952,2.78-19.016,7.844
        L7.844,226.914C2.76,231.998-0.02,238.77,0,245.974c-0.02,7.244,2.76,14.02,7.844,19.096l177.412,177.412
        c5.064,5.06,11.812,7.844,19.016,7.844c7.196,0,13.944-2.788,19.008-7.844l16.104-16.112c5.068-5.056,7.848-11.808,7.848-19.008
        c0-7.196-2.78-13.592-7.848-18.652L134.72,284.406h329.992c14.828,0,27.288-12.78,27.288-27.6v-22.788
        C492,219.198,479.172,207.418,464.344,207.418z"/>
    </g>
  </g>
</svg>
`;

function reencodeURI(uri) {
  return encodeURIComponent(decodeURIComponent(uri));
}

function getHref(tag) {
  return tag.getAttribute('href');
}

function findByHref(href) {
  return allLinks.filter((link) => {
    return reencodeURI(getHref(link)) === reencodeURI(href)
  });
}

function findWholeNumberInText(text, matchNumber) {
  const numbers = text.match(/\d+/g);
  return numbers
    && numbers.length
    && numbers.map((x) => parseInt(x, 10)).some((number) => number === matchNumber);
}

function findByInfoFile(infoFile) {
  const found = ['mkv', 'mp4', 'avi'].reduce((last, current) => {
    const element = findByHref(infoFile.replace(infoRegex, '.' + current))[0];
    return element || last;
  }, null);
  return found;
}

function deduplicateJointEpisode(textContent) {
  return new Promise((resolve, reject) => {
    const lns = textContent.split('\n');
    const result = [];
    let passed = 0;
    for (const line of lns) {
      if (line.startsWith('<episodedetails>')) {
        if (passed === 1) {
          break;
        }
        passed = 1;
      }
      result.push(line);
    }
    resolve(result.join('\n'));
  });
}

const parser = new window.DOMParser();
async function createXMLRequest(nfo) {
  return fetch(nfo)
    .then((response) => response.text())
    .then((text) => deduplicateJointEpisode(text))
    .then((str) => parser.parseFromString(str, 'text/xml'));
}

// Fill metadata boxes, generate buttons
function fillMeta(
  content, original, nfo, movieTitle, movieDescription, movieButtons
) {
  infoFilesAccounted += 1;
  if (!content) {
    return;
  }

  const titleEl = content.querySelector('title');
  const plotEl = content.querySelector('plot');
  const airedEl = content.querySelector('aired');
  const premieredEl = content.querySelector('premiered');
  const imdbEl = content.querySelector('uniqueid[type="imdb"]');
  const tvdbEl = content.querySelector('uniqueid[type="tvdb"]');

  if (!titleEl || !plotEl) {
    return;
  }

  if (airedEl || premieredEl) {
    const timestamp = original.parentElement.parentElement.querySelector('.timestamp');
    if (timestamp) {
      timestamp.innerText = (airedEl || premieredEl).textContent;
    }
  }

  const episode = content.querySelector('episode');
  const season = content.querySelector('season');
  let title = titleEl.textContent
  if (episode && season) {
    title = `(S${season.textContent} E${episode.textContent}) ` + title;
    original.parentElement.setAttribute('data-episode', episode.textContent);
  }

  movieTitle.innerText = title;
  movieDescription.innerText = plotEl.textContent;

  if (imdbEl) {
    const imlink = document.createElement('a');
    imlink.target = '_blank';
    imlink.innerText = 'IMDb';
    imlink.href = `https://www.imdb.com/title/${imdbEl.textContent}`;
    movieButtons.appendChild(imlink);
  }

  if (tvdbEl) {
    const tvlink = document.createElement('a');
    tvlink.target = '_blank';
    tvlink.innerText = 'The TVDB';
    tvlink.href = `http://www.thetvdb.com/?tab=series&id=${tvdbEl.textContent}`;
    movieButtons.appendChild(tvlink);
  }

  // Add "copy direct url" button
  if (
    getHref(nfo) !== 'tvshow.nfo'
    && navigator
    && navigator.clipboard
    && navigator.clipboard.writeText
  ) {
    const copybutton = document.createElement('button');
    copybutton.innerText = 'Copy direct URL';
    movieButtons.appendChild(copybutton);
    copybutton.addEventListener('click', (e) => {
      e.preventDefault();
      const popup = document.createElement('div');
      popup.className = 'tooltip';
      popup.innerText = 'Copied!';
      const url = window.location.href + reencodeURI(getHref(original));
      navigator.clipboard.writeText(url).then(() => {
        copybutton.appendChild(popup);
        setTimeout(() => copybutton.removeChild(popup), 1000);
      });
    });
  }
}

// Replace list entry with a metadata box
// Either create or populate
function createOrImproveMovieMeta(original, thumbnail, nfo) {
  let imgTag = `<img class="thumbnail" src="${thumbnail ? reencodeURI(getHref(thumbnail)) : ''}"/>`;
  let movieTitle = `<div class="movie-title">${original.innerText}</div>`;
  let movieDescription = `<div class="movie-description"></div>`;
  let movieButtons = `<div class="movie-buttons"></div>`;

  if (!thumbnail && !nfo) {
    return;
  }

  if (original.parentElement.classList.contains('enhanced')) {
    imgTag = original.querySelector('.thumbnail');
    movieTitle = original.querySelector('.movie-title');
    movieDescription = original.querySelector('.movie-description');
    movieButtons = original.querySelector('.movie-buttons');
    if (thumbnail) {
      imgTag.src = reencodeURI(getHref(thumbnail));
    }
  } else {
    original.classList.add('movie');
    original.innerHTML = imgTag + '<div class="meta-wrap">' + movieTitle + movieDescription + movieButtons + '</div>';
    original.parentElement.classList.add('enhanced');
    // quick innerHTML hack to create elements here lol
    imgTag = original.querySelector('.thumbnail');
    movieTitle = original.querySelector('.movie-title');
    movieDescription = original.querySelector('.movie-description');
    movieButtons = original.querySelector('.movie-buttons');
  }

  // Fetch metadata from the nfo file and populate the info box
  if (nfo) {
    createXMLRequest(reencodeURI(getHref(nfo)))
      .then((content) => fillMeta(content, original, nfo, movieTitle, movieDescription, movieButtons))
      .catch((e) => {
        infoFilesAccounted += 1;
        console.error(e);
      });
  }
}

// Promise that resolves when all info files that were found have been parsed
function waitUntilInfoComplete() {
  return new Promise((resolve, reject) => {
    if (infoFilesAccounted >= infoFiles) {
      resolve(true);
      return;
    }

    let seconds = 0;
    const accountWait = setInterval(() => {
      if (infoFilesAccounted >= infoFiles || seconds > 20) {
        clearInterval(accountWait);
        resolve(true);
        return;
      }
      seconds += 1;
    }, 500);
  });
}

// Get episode name or name of file
const getCellValue = (tr, idx) =>
  tr.children[idx].getAttribute('data-episode')
  || tr.children[idx].innerText
  || tr.children[idx].textContent;

// Compare numeric or (locale-aware, numeric-aware) by string values
const comparer = (idx, asc) => (a, b) => ((v1, v2) =>
    v1 !== '' && v2 !== '' && !isNaN(v1) && !isNaN(v2) ? v1 - v2 : v1.toString().localeCompare(v2, 'et', { numeric: true })
    )(getCellValue(asc ? a : b, idx), getCellValue(asc ? b : a, idx));

// Table sort by column index
const sortTableValues = (index) =>
  Array.from(tableElem.querySelectorAll('tr:nth-child(n+2):not(.btn-back)'))
  .sort(comparer(index, this.asc = !this.asc))
  .forEach((tr) => tableElem.appendChild(tr));

let tvShow;
function accountForMetadata() {
  allLinks.forEach((link) => {
    const url = getHref(link);

    // If nfo or jpg (or subtitle, for hiding it)..
    if (url.match(infoRegex)) {
      // Hide metadata file
      link.parentElement.parentElement.style.display = 'none';
      let findOriginal
      // Place TV show information in the beginning of the table
      if (url === 'tvshow.nfo' || url === 'poster.jpg') {
        if (url === 'poster.jpg' && !allLinks.find((found) => getHref(found) === 'tvshow.nfo')) {
          findOriginal = document.querySelector('a:not([href=".."])');
        } else {
          if (tvShow) {
            findOriginal = tvShow;
          } else {
            const wrapper = document.createElement('div');
            wrapper.className = 'highlight';
            tvShow = document.createElement('a');
            tvShow.className = 'movie';
            wrapper.appendChild(tvShow);
            bodyInner.insertBefore(wrapper, tableElem);
            findOriginal = tvShow;
          }
        }
      // Give posters to seasons
      } else if (url.startsWith('season') && url.includes('poster')) {
        // Find season by number
        const sn = url.match(/season(\d+)/);
        if (sn) {
          findOriginal = allLinks.find(
            ({ innerText }) => {
              return innerText.endsWith('/')
                && findWholeNumberInText(innerText, parseInt(sn[1], 10));
            });
        // Find specials folder
        } else if (url.includes('specials')) {
          findOriginal = allLinks.find(({ innerText }) => {
            const matchAgainst = innerText.toLowerCase();
            return (matchAgainst.startsWith('specials') || matchAgainst.startsWith('extras'))
              && innerText.endsWith('/');
          });
        }
      // Find the video file associated with this info file
      } else {
        findOriginal = findByInfoFile(url);
      }

      // Populate video file/season folder/tv show info box
      if (findOriginal) {
        if (url.match(/.nfo$/)) {
          infoFiles += 1;
        }
        createOrImproveMovieMeta(findOriginal,
          url.match(/.jpg$/) ? link : undefined,
          url.match(/.nfo$/) ? link : undefined,
        );
      }
    }

    // Replace the back button with a more descriptive one
    if (url === '..') {
      link.parentElement.parentElement.classList.add('btn-back');
      link.innerHTML = arrow + 'Back (..)';
    }
  });
  waitUntilInfoComplete().then(() => sortTableValues(0));
}

function createToggleCheckbox(field, value, description) {
  const form = document.createElement('div');
  const checkbox = document.createElement('input');
  const label = document.createElement('label');
  form.className = 'form ' + field;
  checkbox.type = 'checkbox';
  checkbox.id = field
  label.innerText = description;
  label.setAttribute('for', field);
  form.appendChild(checkbox);
  form.appendChild(label)
  bodyInner.appendChild(form);

  checkbox.addEventListener('change', (e) => {
    if (checkbox.checked) {
      window.localStorage.setItem(field, 'true');
    } else {
      window.localStorage.removeItem(field);
    }
    window.location.reload();
  });
  checkbox.checked = value === 'true';
}

if ('localStorage' in window) {
  const plainMode = window.localStorage.getItem('plainMode');
  if (plainMode !== 'true') {
    accountForMetadata();
  }
  createToggleCheckbox('plainMode', plainMode, 'Disable metadata / display plain index listing (less bandwidth required)');
} else {
  accountForMetadata();
}

document.querySelectorAll('th').forEach((th) => th.addEventListener('click', (() => {
  sortTableValues(Array.from(th.parentNode.children).indexOf(th));
})));