Telegram Media Downloader

Allow you to download images, GIFs, videos, and voice messages on Telegram webapp from private channels which disable downloading and restrict saving content

目前為 2023-11-09 提交的版本,檢視 最新版本

您需要先安裝使用者腳本管理器擴展,如 TampermonkeyGreasemonkeyViolentmonkey 之後才能安裝該腳本。

You will need to install an extension such as Tampermonkey to install this script.

您需要先安裝使用者腳本管理器擴充功能,如 TampermonkeyViolentmonkey 後才能安裝該腳本。

您需要先安裝使用者腳本管理器擴充功能,如 TampermonkeyUserscripts 後才能安裝該腳本。

你需要先安裝一款使用者腳本管理器擴展,比如 Tampermonkey,才能安裝此腳本

您需要先安裝使用者腳本管理器擴充功能後才能安裝該腳本。

(我已經安裝了使用者腳本管理器,讓我安裝!)

你需要先安裝一款使用者樣式管理器擴展,比如 Stylus,才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展,比如 Stylus,才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展,比如 Stylus,才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展後才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展後才能安裝此樣式

你需要先安裝一款使用者樣式管理器擴展後才能安裝此樣式

(我已經安裝了使用者樣式管理器,讓我安裝!)

// ==UserScript==
// @name         Telegram Media Downloader
// @name:zh-CN   Telegram下载器
// @version      1.053
// @namespace    https://github.com/Neet-Nestor/Telegram-Media-Downloader
// @description  Allow you to download images, GIFs, videos, and voice messages on Telegram webapp from private channels which disable downloading and restrict saving content
// @description:zh-cn 从禁止下载的Telegram频道中下载图片、视频及语音消息
// @author       Nestor Qin
// @license      GNU GPLv3
// @website      https://github.com/Neet-Nestor/Telegram-Media-Downloader
// @match        https://web.telegram.org/*
// @match        https://webk.telegram.org/*
// @match        https://webz.telegram.org/*
// @icon         https://img.icons8.com/color/452/telegram-app--v5.png
// ==/UserScript==

(function () {
  const logger = {
    info: (message, fileName = null) => {
      console.log(
        `[Tel Download] ${fileName ? `${fileName}: ` : ""}${message}`
      );
    },
    error: (message, fileName = null) => {
      console.error(
        `[Tel Download] ${fileName ? `${fileName}: ` : ""}${message}`
      );
    },
  };
  const contentRangeRegex = /^bytes (\d+)-(\d+)\/(\d+)$/;
  const REFRESH_DELAY = 500;

  const tel_download_video = (url) => {
    let _blobs = [];
    let _next_offset = 0;
    let _total_size = null;
    let _file_extension = "mp4";

    let fileName =
      (Math.random() + 1).toString(36).substring(2, 10) + "." + _file_extension;

    // Some video src is in format:
    // 'stream/{"dcId":5,"location":{...},"size":...,"mimeType":"video/mp4","fileName":"xxxx.MP4"}'
    try {
      const metadata = JSON.parse(
        decodeURIComponent(url.split("/")[url.split("/").length - 1])
      );
      if (metadata.fileName) {
        fileName = metadata.fileName;
      }
    } catch (e) {
      // Invalid JSON string, pass extracting fileName
    }
    logger.info(`URL: ${url}`, fileName);

    const fetchNextPart = () => {
      fetch(url, {
        method: "GET",
        headers: {
          Range: `bytes=${_next_offset}-`,
        },
        "User-Agent":
          "User-Agent Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:109.0) Gecko/20100101 Firefox/117.0",
      })
        .then((res) => {
          if (![200, 206].includes(res.status)) {
            throw new Error("Non 200/206 response was received: " + res.status);
          }
          const mime = res.headers.get("Content-Type").split(";")[0];
          if (!mime.startsWith("video/")) {
            throw new Error("Get non video response with MIME type " + mime);
          }
          _file_extension = mime.split("/")[1];
          fileName =
            fileName.substring(0, fileName.indexOf(".") + 1) + _file_extension;

          const match = res.headers
            .get("Content-Range")
            .match(contentRangeRegex);

          const startOffset = parseInt(match[1]);
          const endOffset = parseInt(match[2]);
          const totalSize = parseInt(match[3]);

          if (startOffset !== _next_offset) {
            logger.error("Gap detected between responses.", fileName);
            logger.info("Last offset: " + _next_offset, fileName);
            logger.info("New start offset " + match[1], fileName);
            throw "Gap detected between responses.";
          }
          if (_total_size && totalSize !== _total_size) {
            logger.error("Total size differs", fileName);
            throw "Total size differs";
          }

          _next_offset = endOffset + 1;
          _total_size = totalSize;

          logger.info(
            `Get response: ${res.headers.get(
              "Content-Length"
            )} bytes data from ${res.headers.get("Content-Range")}`,
            fileName
          );
          logger.info(
            `Progress: ${((_next_offset * 100) / _total_size).toFixed(0)}%`,
            fileName
          );
          return res.blob();
        })
        .then((resBlob) => {
          _blobs.push(resBlob);
        })
        .then(() => {
          if (!_total_size) {
            throw new Error("_total_size is NULL");
          }

          if (_next_offset < _total_size) {
            fetchNextPart();
          } else {
            save();
          }
        })
        .catch((reason) => {
          logger.error(reason, fileName);
        });
    };

    const save = () => {
      logger.info("Finish downloading blobs", fileName);
      logger.info("Concatenating blobs and downloading...", fileName);

      const blob = new Blob(_blobs, { type: "video/mp4" });
      const blobUrl = window.URL.createObjectURL(blob);

      logger.info("Final blob size: " + blob.size + " bytes", fileName);

      const a = document.createElement("a");
      document.body.appendChild(a);
      a.href = blobUrl;
      a.download = fileName;
      a.click();
      document.body.removeChild(a);
      window.URL.revokeObjectURL(blobUrl);

      logger.info("Download triggered", fileName);
    };

    fetchNextPart();
  };

  const tel_download_audio = (url) => {
    let _blobs = [];
    let _next_offset = 0;
    let _total_size = null;
    const fileName = (Math.random() + 1).toString(36).substring(2, 10) + ".ogg";

    const fetchNextPart = () => {
      fetch(url, {
        method: "GET",
        headers: {
          Range: `bytes=${_next_offset}-`,
        },
      })
        .then((res) => {
          if (res.status !== 206 && res.status !== 200) {
            logger.error(
              "Non 200/206 response was received: " + res.status,
              fileName
            );
            return;
          }

          const mime = res.headers.get("Content-Type").split(";")[0];
          if (!mime.startsWith("audio/")) {
            logger.error(
              "Get non audio response with MIME type " + mime,
              fileName
            );
            throw "Get non audio response with MIME type " + mime;
          }

          try {
            const match = res.headers
              .get("Content-Range")
              .match(contentRangeRegex);

            const startOffset = parseInt(match[1]);
            const endOffset = parseInt(match[2]);
            const totalSize = parseInt(match[3]);

            if (startOffset !== _next_offset) {
              logger.error("Gap detected between responses.");
              logger.info("Last offset: " + _next_offset);
              logger.info("New start offset " + match[1]);
              throw "Gap detected between responses.";
            }
            if (_total_size && totalSize !== _total_size) {
              logger.error("Total size differs");
              throw "Total size differs";
            }

            _next_offset = endOffset + 1;
            _total_size = totalSize;
          } finally {
            logger.info(
              `Get response: ${res.headers.get(
                "Content-Length"
              )} bytes data from ${res.headers.get("Content-Range")}`
            );
            return res.blob();
          }
        })
        .then((resBlob) => {
          _blobs.push(resBlob);
        })
        .then(() => {
          if (_next_offset < _total_size) {
            fetchNextPart();
          } else {
            save();
          }
        })
        .catch((reason) => {
          logger.error(reason, fileName);
        });
    };

    const save = () => {
      logger.info(
        "Finish downloading blobs. Concatenating blobs and downloading...",
        fileName
      );

      let blob = new Blob(_blobs, { type: "audio/ogg" });
      const blobUrl = window.URL.createObjectURL(blob);

      logger.info("Final blob size in bytes: " + blob.size, fileName);

      blob = 0;

      const a = document.createElement("a");
      document.body.appendChild(a);
      a.href = blobUrl;
      a.download = fileName;
      a.click();
      document.body.removeChild(a);
      window.URL.revokeObjectURL(blobUrl);

      logger.info("Download triggered", fileName);
    };

    fetchNextPart();
  };

  const tel_download_image = (imageUrl) => {
    const fileName =
      (Math.random() + 1).toString(36).substring(2, 10) + ".jpeg"; // assume jpeg

    const a = document.createElement("a");
    document.body.appendChild(a);
    a.href = imageUrl;
    a.download = fileName;
    a.click();
    document.body.removeChild(a);

    logger.info("Download triggered", fileName);
  };

  logger.info("Initialized");

  // For webz /a/ webapp
  setInterval(() => {
    // All media opened are located in .media-viewer-movers > .media-viewer-aspecter
    const mediaContainer = document.querySelector(
      "#MediaViewer .MediaViewerSlide--active"
    );
    if (!mediaContainer) return;
    const mediaViewerActions = document.querySelector(
      "#MediaViewer .MediaViewerActions"
    );
    if (!mediaViewerActions) return;

    const videoPlayer = mediaContainer.querySelector(
      ".MediaViewerContent > .VideoPlayer"
    );
    const img = mediaContainer.querySelector(".MediaViewerContent > div > img");
    // 1. Video player detected - Video or GIF
    // container > .MediaViewerSlides > .MediaViewerSlide > .MediaViewerContent > .VideoPlayer > video[src]
    const downloadIcon = document.createElement("i");
    downloadIcon.className = "icon icon-download";
    const downloadButton = document.createElement("button");
    downloadButton.className =
      "Button smaller translucent-white round tel-download";
    downloadButton.setAttribute("type", "button");
    downloadButton.setAttribute("title", "Download");
    downloadButton.setAttribute("aria-label", "Download");
    if (videoPlayer) {
      const videoUrl = videoPlayer.querySelector("video").currentSrc;
      downloadButton.setAttribute("data-tel-download-url", videoUrl);
      downloadButton.appendChild(downloadIcon);
      downloadButton.onclick = () => {
        tel_download_video(videoUrl);
      };

      // Add download button to video controls
      const controls = videoPlayer.querySelector(".VideoPlayerControls");
      if (controls) {
        const buttons = controls.querySelector(".buttons");
        if (!buttons.querySelector("button.tel-download")) {
          const spacer = buttons.querySelector(".spacer");
          spacer.after(downloadButton);
        }
      }

      // Add/Update/Remove download button to topbar
      if (mediaViewerActions.querySelector("button.tel-download")) {
        const telDownloadButton = mediaViewerActions.querySelector(
          "button.tel-download"
        );
        if (
          mediaViewerActions.querySelectorAll('button[title="Download"]')
            .length > 1
        ) {
          // There's existing download button, remove ours
          mediaViewerActions.querySelector("button.tel-download").remove();
        } else if (
          telDownloadButton.getAttribute("data-tel-download-url") !== videoUrl
        ) {
          // Update existing button
          telDownloadButton.onclick = () => {
            tel_download_video(videoUrl);
          };
          telDownloadButton.setAttribute("data-tel-download-url", videoUrl);
        }
      } else if (
        !mediaViewerActions.querySelector('button[title="Download"]')
      ) {
        // Add the button if there's no download button at all
        mediaViewerActions.prepend(downloadButton);
      }
    } else if (img && img.src) {
      downloadButton.setAttribute("data-tel-download-url", img.src);
      downloadButton.appendChild(downloadIcon);
      downloadButton.onclick = () => {
        tel_download_image(img.src);
      };

      // Add/Update/Remove download button to topbar
      if (mediaViewerActions.querySelector("button.tel-download")) {
        const telDownloadButton = mediaViewerActions.querySelector(
          "button.tel-download"
        );
        if (
          mediaViewerActions.querySelectorAll('button[title="Download"]')
            .length > 1
        ) {
          // There's existing download button, remove ours
          mediaViewerActions.querySelector("button.tel-download").remove();
        } else if (
          telDownloadButton.getAttribute("data-tel-download-url") !== img.src
        ) {
          // Update existing button
          telDownloadButton.onclick = () => {
            tel_download_image(img.src);
          };
          telDownloadButton.setAttribute("data-tel-download-url", img.src);
        }
      } else if (
        !mediaViewerActions.querySelector('button[title="Download"]')
      ) {
        // Add the button if there's no download button at all
        mediaViewerActions.prepend(downloadButton);
      }
    }
  }, REFRESH_DELAY);

  // For webk /k/ webapp
  setInterval(() => {
    /* Voice Message */
    const pinnedAudio = document.body.querySelector(".pinned-audio");
    let dataMid;
    let downloadButtonPinnedAudio =
      document.body.querySelector("._tel_download_button_pinned_container") ||
      document.createElement("button");
    if (pinnedAudio) {
      dataMid = pinnedAudio.getAttribute("data-mid");
      downloadButtonPinnedAudio.className =
        "btn-icon tgico-download _tel_download_button_pinned_container";
      downloadButtonPinnedAudio.innerHTML =
        '<span class="tgico button-icon">\uE93E</span>';
    }
    const voiceMessages = document.body.querySelectorAll("audio-element");
    voiceMessages.forEach((voiceMessage) => {
      const bubble = voiceMessage.closest(".bubble");
      if (
        !bubble ||
        bubble.querySelector("._tel_download_button_pinned_container")
      ) {
        return; /* Skip if there's already a download button */
      }
      if (
        dataMid &&
        downloadButtonPinnedAudio.getAttribute("data-mid") !== dataMid &&
        voiceMessage.getAttribute("data-mid") === dataMid
      ) {
        downloadButtonPinnedAudio.onclick = (e) => {
          e.stopPropagation();
          tel_download_audio(link);
        };
        downloadButtonPinnedAudio.setAttribute("data-mid", dataMid);
        const link =
          voiceMessage.audio && voiceMessage.audio.getAttribute("src");
        if (link) {
          pinnedAudio
            .querySelector(".pinned-container-wrapper-utils")
            .appendChild(downloadButtonPinnedAudio);
        }
      }
    });

    // All media opened are located in .media-viewer-movers > .media-viewer-aspecter
    const mediaContainer = document.querySelector(".media-viewer-whole");
    if (!mediaContainer) return;
    const mediaAspecter = mediaContainer.querySelector(
      ".media-viewer-movers .media-viewer-aspecter"
    );
    const mediaButtons = mediaContainer.querySelector(
      ".media-viewer-topbar .media-viewer-buttons"
    );
    if (!mediaAspecter || !mediaButtons) return;

    // If the download button is hidden, we can simply unhide it
    if (mediaButtons.querySelector(".btn-icon.tgico-download")) {
      const button = mediaButtons.querySelector(
        "button.btn-icon.tgico-download"
      );
      if (button.classList.contains("hide")) {
        button.classList.remove("hide");
      }
    }
    // If forward button is hidden, we can simply unhide it too
    if (mediaButtons.querySelector("button.btn-icon.tgico-forward")) {
      const button = mediaButtons.querySelector(
        "button.btn-icon.tgico-forward"
      );
      if (button.classList.contains("hide")) {
        button.classList.remove("hide");
      }
    }

    if (mediaAspecter.querySelector(".ckin__player")) {
      // 1. Video player detected - Video and it has finished initial loading
      // container > .ckin__player > video[src]

      // add download button to videos
      const controls = mediaAspecter.querySelector(
        ".default__controls.ckin__controls"
      );
      const videoUrl = mediaAspecter.querySelector("video").src;

      if (controls && !controls.querySelector(".tel-download")) {
        const brControls = controls.querySelector(
          ".bottom-controls .right-controls"
        );
        const downloadButton = document.createElement("button");
        downloadButton.className =
          "btn-icon default__button tgico-download tel-download";
        downloadButton.innerHTML =
          '<span class="tgico button-icon">\uE93E</span>';
        downloadButton.setAttribute("type", "button");
        downloadButton.setAttribute("title", "Download");
        downloadButton.setAttribute("aria-label", "Download");
        downloadButton.onclick = () => {
          tel_download_video(videoUrl);
        };
        brControls.prepend(downloadButton);
      }
    } else if (
      mediaAspecter.querySelector("video") &&
      mediaAspecter.querySelector("video") &&
      !mediaButtons.querySelector("button.btn-icon.tgico-download")
    ) {
      // 2. Video HTML element detected, could be either GIF or unloaded video
      // container > video[src]
      const videoUrl = mediaAspecter.querySelector("video").src;
      const downloadButton = document.createElement("button");
      downloadButton.className = "btn-icon tgico-download tel-download";
      downloadButton.innerHTML =
        '<span class="tgico button-icon">\uE93E</span>';
      downloadButton.setAttribute("type", "button");
      downloadButton.setAttribute("title", "Download");
      downloadButton.setAttribute("aria-label", "Download");
      downloadButton.onclick = () => {
        tel_download_video(videoUrl);
      };
      mediaButtons.prepend(downloadButton);
    } else if (!mediaButtons.querySelector("button.btn-icon.tgico-download")) {
      // 3. Image without download button detected
      // container > img.thumbnail
      if (!mediaAspecter.querySelector("img.thumbnail")) {
        return;
      }
      const imageUrl = mediaAspecter.querySelector("img.thumbnail").src;
      if (!imageUrl) {
        return;
      }
      const downloadButton = document.createElement("button");
      downloadButton.className = "btn-icon tgico-download tel-download";
      downloadButton.innerHTML =
        '<span class="tgico button-icon">\uE93E</span>';
      downloadButton.setAttribute("type", "button");
      downloadButton.setAttribute("title", "Download");
      downloadButton.setAttribute("aria-label", "Download");
      downloadButton.onclick = () => {
        tel_download_image(imageUrl);
      };
      mediaButtons.prepend(downloadButton);
    }
  }, REFRESH_DELAY);
})();