// ==UserScript==
// @name        khinsider mass downloader
// @description mass downloader for downloads.khinsider.com
// @version     1.0.1
// @namespace   https://venipa.net/
// @license     GPL-3.0
// @author      Venipa <admin@venipa.net>
// @icon        https://www.google.com/s2/favicons?sz=64&domain=downloads.khinsider.com
// @match       https://*.khinsider.com/game-soundtracks/*
// @grant       GM_xmlhttpRequest
// @run-at      document-end
// @require     https://cdn.jsdelivr.net/npm/jszip@3.9.1/dist/jszip.min.js
// @require     https://cdn.jsdelivr.net/npm/file-saver@2.0.4/dist/FileSaver.min.js
// @connect     vgmsite.com
// @connect     vgmtreasurechest.com
// @downloadURL none
// ==/UserScript==

(function() {
  "use strict";
  const a = (e) => {
    if (["interactive", "complete"].indexOf(document.readyState) > -1)
      e();
    else {
      let t = false;
      document.addEventListener("DOMContentLoaded", () => {
        t || (t = true, setTimeout(e, 1));
      });
    }
  };
  const appInit = function() {
    function sanitizeFilename(input, options) {
      var illegalRe = /[\/\?<>\\:\*\|":]/g;
      var controlRe = /[\x00-\x1f\x80-\x9f]/g;
      var reservedRe = /^\.+$/;
      var windowsReservedRe = /^(con|prn|aux|nul|com[0-9]|lpt[0-9])(\..*)?$/i;
      function sanitize(input2, replacement) {
        var sanitized = input2.replace(illegalRe, replacement).replace(controlRe, replacement).replace(reservedRe, replacement).replace(windowsReservedRe, replacement);
        return sanitized.split("").splice(0, 255).join("");
      }
      return function(input2, options2) {
        var replacement = options2 && options2.replacement || "";
        var output = sanitize(input2, replacement);
        if (replacement === "") {
          return output;
        }
        return sanitize(output, "");
      }(input, options);
    }
    const downloadStatus = {
      running: false,
      skip: false
    };
    const queue = [];
    console.log("loaded mass downloader");
    var btns = document.querySelector('p[align="left"]');
    const TEXTS = {
      /**
       *
       * @param {string} type
       */
      DOWNLOAD(type) {
        return "Download Album (" + type + ")";
      },
      LOADING: "LOADING...",
      /**
       *
       * @param {number} value
       * @param {number} max
       * @param {string} type
       */
      PREPARE(max, type) {
        return "Preparing audio downloads... (Audio Files: " + max + ") (" + type + ")";
      },
      /**
       *
       * @param {number} value
       * @param {number} max
       * @param {string} type
       */
      PROGRESS_ITEM(value, max, type) {
        const maxLength = max.toString().length;
        return "Fetching... (" + value.toString().padStart(maxLength) + " / " + max + ") (" + type + ")";
      },
      ARCHIVE_START(value, type) {
        return "Compressing... " + value + " (" + type + ")";
      }
    };
    var dlButton = function(type) {
      var el = document.createElement("button");
      "btn khinsider-massdl".split(" ").forEach((cl) => el.classList.add(cl));
      el.innerText = TEXTS.DOWNLOAD(type || "default");
      el.dataset.type = type;
      return el;
    };
    var checkFlac = () => Array.from(document.querySelectorAll("#songlist_header th>b")).findIndex(
      (x) => x.innerText.trim() === "FLAC"
    ) !== -1;
    var spacerEl = function(x, y) {
      var el = document.createElement("div");
      el.style.width = (x || 0) + "px";
      el.style.height = (y || 0) + "px";
      el.style.display = "inline-block";
      return el;
    };
    var mp3DL = dlButton("mp3");
    var flacDL = dlButton("flac");
    var hasFlac = checkFlac();
    const setDisabledState = function(state) {
      mp3DL.disabled = state;
      if (hasFlac)
        flacDL.disabled = state;
    };
    const get = (url, responseType = "json", retry = 3) => new Promise((resolve, reject) => {
      try {
        GM_xmlhttpRequest({
          method: "GET",
          url,
          responseType,
          onerror: (e) => {
            if (retry === 0)
              reject(e);
            else {
              console.warn("Network error, retry.");
              if (e.status == 415) {
                url = url.slice(0, url.lastIndexOf(".")) + ".mp3";
              }
              setTimeout(() => {
                resolve(get(url, responseType, retry - 1));
              }, 1e3);
            }
          },
          onload: ({ status, response }) => {
            if ([200, 206].includes(status))
              resolve(response);
            else if (status === 415)
              setTimeout(() => {
                resolve(
                  get(
                    url.slice(0, url.lastIndexOf(".")) + ".mp3",
                    responseType,
                    retry - 1
                  )
                );
              }, 500);
            else if (retry === 0)
              reject(`${status} ${url}`);
            else {
              console.warn(status, url);
              setTimeout(() => {
                resolve(get(url, responseType, retry - 1));
              }, 500);
            }
          }
        });
      } catch (error) {
        reject(error);
      }
    }), requestPage = (url) => new Promise((resolve, reject) => {
      try {
        GM_xmlhttpRequest({
          method: "GET",
          url,
          responseType: "text",
          onerror: reject,
          onload: ({ status, response, error }) => {
            if (status === 200)
              resolve(response);
            reject(error);
          }
        });
      } catch (error) {
        reject(error);
      }
    });
    const startQueue = async (typeOfDL) => {
      if (!downloadStatus.running && queue.length > 0) {
        const dl = typeOfDL === "flac" ? flacDL : mp3DL;
        const zip = new JSZip();
        let i = 0;
        let l = queue.length;
        downloadStatus.running = true;
        dl.innerText = TEXTS.PREPARE(l, typeOfDL);
        do {
          const { url: meta, data } = await queue[0]();
          const { url, title } = meta;
          if (!data || data.size <= 0) {
            queue.shift();
            dl.innerText = TEXTS.PROGRESS_ITEM(i++, l, typeOfDL);
            continue;
          }
          let fname = url.split("/").reverse()[0];
          fname = fname.slice(0, fname.lastIndexOf("."));
          let fext = typeOfDL === "flac" ? "flac" : "mp3";
          if (data.type === "audio/mpeg")
            fext = "mp3";
          zip.file(
            sanitizeFilename(title).replace(/\.(mp3|flac)$/g, "") + "." + fext,
            data
          );
          queue.shift();
          dl.innerText = TEXTS.PROGRESS_ITEM(++i, l, typeOfDL);
        } while (queue.length > 0);
        downloadStatus.running = false;
        dl.innerText = TEXTS.ARCHIVE_START("0%", typeOfDL);
        return await zip.generateAsync({ type: "blob" }, (progress) => {
          dl.innerText = TEXTS.ARCHIVE_START(
            progress.percent.toFixed(2) + "%",
            typeOfDL
          );
        }).catch((err) => {
          console.error("failed to generate zip", err);
          return Promise.reject(err);
        });
      }
      return null;
    };
    const onClick = function(ev) {
      ev.preventDefault();
      if (ev.target.disabled)
        return;
      ev.target.disabled = true;
      setDisabledState(true);
      const typeOfDL = ev.target.dataset.type;
      const typeOfExt = typeOfDL === "flac" ? ".flac" : typeOfDL === "mp3" ? ".mp3" : "null";
      const header = Array.from(
        document.querySelectorAll("#songlist #songlist_header > th")
      );
      const hasCD = !!header.find(
        (x) => x.innerText && x.innerText.trim() === "CD"
      ), hasNumber = !!header.find(
        (x) => x.innerText && x.innerText.trim() === "#"
      );
      const urls = Array.from(
        document.querySelectorAll("#songlist #songlist_header ~ tr")
      ).filter((x) => x.querySelectorAll("td.clickable-row a").length > 0).map((x) => {
        const fields = x.querySelectorAll("td");
        let title = x.querySelectorAll("td.clickable-row a")[0].innerText, url = x.querySelector(".playlistDownloadSong a").href, meta = {
          CD: hasCD ? fields[1].innerText : null,
          PIECE: hasCD ? fields[2].innerText : hasNumber ? fields[1].innerText : null
        };
        title = title.replace(/\.(mp3|flac)$/g, "");
        return {
          title: (meta.CD ? meta.CD + "-" : "") + (meta.PIECE ? meta.PIECE.trim().match(/(\d+)/i)[0] + " " : "") + title + typeOfExt,
          ext: typeOfExt,
          url
        };
      });
      if (urls.length === 0) {
        ev.target.disabled = false;
        setDisabledState(false);
        return;
      }
      const pageName = document.querySelector("#pageContent>h2").innerText;
      queue.push(
        ...urls.map((x) => {
          return async () => {
            try {
              return {
                url: x,
                data: await requestPage(x.url).then((page) => {
                  const container = document.implementation.createHTMLDocument().documentElement;
                  container.style.display = "none";
                  container.innerHTML = page;
                  const fileUrl = Array.from(
                    container.querySelectorAll(".songDownloadLink")
                  ).map(
                    (s) => s.parentElement
                  ).find((d) => d.href.endsWith(x.ext)).href;
                  return get(fileUrl, "blob", 2);
                }).catch((err) => {
                  console.error(err);
                  return null;
                })
              };
            } catch (ex) {
              console.error(ex);
              return { url: x, data: null };
            }
          };
        })
      );
      startQueue(typeOfDL).then((data) => {
        ev.target.disabled = false;
        setDisabledState(false);
        if (data) {
          saveAs(data, pageName + ".zip");
          ev.target.innerText = TEXTS.DOWNLOAD(typeOfDL);
        }
      });
    };
    mp3DL.onclick = onClick;
    if (hasFlac)
      flacDL.onclick = onClick;
    if (btns) {
      btns.appendChild(mp3DL);
      if (hasFlac) {
        btns.appendChild(spacerEl(8, 0));
        btns.appendChild(flacDL);
      }
    }
  };
  a(appInit);
})();