Coomer Image Download Button

Adds a small download icon to images on Coomer post pages.

Aby zainstalować ten skrypt, wymagana jest instalacje jednego z następujących rozszerzeń: Tampermonkey, Greasemonkey lub Violentmonkey.

Aby zainstalować ten skrypt, wymagana jest instalacje jednego z następujących rozszerzeń: Tampermonkey, Violentmonkey.

Aby zainstalować ten skrypt, wymagana jest instalacje jednego z następujących rozszerzeń: Tampermonkey, Violentmonkey.

Aby zainstalować ten skrypt, wymagana będzie instalacja rozszerzenia Tampermonkey lub Userscripts.

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

Aby zainstalować ten skrypt, musisz zainstalować rozszerzenie menedżera skryptów użytkownika.

(Mam już menedżera skryptów użytkownika, pozwól mi to zainstalować!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

Będziesz musiał zainstalować rozszerzenie menedżera stylów użytkownika, aby zainstalować ten styl.

Będziesz musiał zainstalować rozszerzenie menedżera stylów użytkownika, aby zainstalować ten styl.

Musisz zainstalować rozszerzenie menedżera stylów użytkownika, aby zainstalować ten styl.

(Mam już menedżera stylów użytkownika, pozwól mi to zainstalować!)

// ==UserScript==
// @name         Coomer Image Download Button
// @namespace    http://tampermonkey.net/
// @version      1.5
// @description  Adds a small download icon to images on Coomer post pages.
// @match        https://coomer.st/*
// @grant        GM_xmlhttpRequest
// @grant        GM_addStyle
// @grant        GM_download
// @connect      *
// @run-at       document-end
// @author       nereids
// @icon         https://icons.duckduckgo.com/ip3/coomer.st.ico
// @license      MIT
// ==/UserScript==

(function () {
  'use strict';

  let imageCounter = 0;
  let lastUrl = location.href;

  // --- Styles ---
  GM_addStyle(`
    .coomer-dl-btn {
      position: absolute;
      bottom: 6px;
      left: 6px;
      width: 30px;
      height: 30px;
      border-radius: 50%;
      background: rgba(0,0,0,0.5);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      cursor: pointer;
      z-index: 2147483647;
      border: none;
      padding: 0;
    }
    .coomer-dl-btn svg { width:20px; height:20px; fill: white; pointer-events: none; }
    .coomer-dl-btn.downloading { opacity: 0.7; transform: scale(0.98); }
  `);

  // SVG download icon
  const ICON_SVG = `<svg xmlns="http://www.w3.org/2000/svg" height="48px" viewBox="0 -960 960 960" width="48px" fill="#e3e3e3"><path d="M434.5-396.5v-329q0-19 13.25-32.25T480.5-771q19 0 32.25 13.25T526-725.5V-395l119-119q13.5-13.5 32-13.5t32 14q13.5 13.5 13.5 32t-13.5 32L512.5-253q-14 14-33.5 14t-33-14L249.5-449.5Q236-463 235.75-481.25t13.75-32.25q14-13.5 32.75-14t32.75 13l119.5 118Z"/></svg>`;

  function getUserAndPost() {
    const userMatch = location.pathname.match(/\/user\/([^/]+)/);
    const postMatch = location.pathname.match(/\/post\/(\d+)/);
    return {
      username: userMatch ? userMatch[1] : "",
      postId: postMatch ? postMatch[1] : ""
    };
  }

  function findOriginal(img) {
    const anc = img.closest('a');
    if (anc && anc.href && /\/data\//.test(anc.href)) {
      return anc.href.split('?')[0];
    }
    if (img.srcset) {
      const candidates = img.srcset.split(',').map(s => s.trim().split(/\s+/)[0]);
      for (const c of candidates) {
        if (/\/data\//.test(c)) return c.split('?')[0];
      }
    }
    const attrs = ['data-src', 'data-full', 'data-original', 'data-img', 'data-lazy-src'];
    for (const a of attrs) {
      const v = img.getAttribute(a);
      if (v && /\/data\//.test(v)) return v.split('?')[0];
    }
    if (!img.src) return null;
    try {
      const u = new URL(img.src, location.href);
      u.pathname = u.pathname.replace('/thumbnail', '');
      if (u.hostname === 'img.coomer.st') u.hostname = 'n4.coomer.st';
      u.search = '';
      return u.toString();
    } catch (e) {
      return img.src.split('?')[0];
    }
  }

  function getExtension(url) {
    const m = url.match(/\.([a-zA-Z0-9]+)(?:\?|$)/);
    return m ? "." + m[1] : ".jpg";
  }

  function buildFilename(url, username, postId) {
    imageCounter += 1;
    return `${username}-${postId}_${imageCounter}${getExtension(url)}`;
  }

  function downloadBinary(url, filename, btn) {
    if (btn) btn.classList.add('downloading');
    GM_xmlhttpRequest({
      method: 'GET',
      url,
      responseType: 'arraybuffer',
      onload(res) {
        if (btn) btn.classList.remove('downloading');
        if (res.status >= 200 && res.status < 300 && res.response) {
          let ct = 'application/octet-stream';
          if (res.responseHeaders) {
            const m = res.responseHeaders.match(/content-type:\s*([^\r\n;]+)/i);
            if (m) ct = m[1].trim();
          }
          const blob = new Blob([res.response], { type: ct });
          const blobUrl = URL.createObjectURL(blob);
          const a = document.createElement('a');
          a.href = blobUrl;
          a.download = filename;
          document.body.appendChild(a);
          a.click();
          a.remove();
          setTimeout(() => URL.revokeObjectURL(blobUrl), 5000);
        } else {
          console.error('Binary download failed, status:', res.status);
          fallbackDownload(url, filename);
        }
      },
      onerror(err) {
        if (btn) btn.classList.remove('downloading');
        console.error('GM_xmlhttpRequest error', err);
        fallbackDownload(url, filename);
      },
      ontimeout() {
        if (btn) btn.classList.remove('downloading');
        console.error('GM_xmlhttpRequest timeout');
        fallbackDownload(url, filename);
      }
    });
  }

  function fallbackDownload(url, filename) {
    try {
      if (typeof GM_download === 'function') {
        try {
          GM_download({ url, name: filename });
          return;
        } catch (e) {
          GM_download(url, filename);
          return;
        }
      }
    } catch (e) {
      console.warn('GM_download fallback failed', e);
    }
    window.open(url, '_blank');
  }

  function addButtonsOnce() {
    const { username, postId } = getUserAndPost();
    if (!username || !postId) return; // only on post pages

    const images = Array.from(document.querySelectorAll('img'));
    images.forEach(img => {
      if (img.dataset.cdlAdded) return;
      if (!img.src || (!img.src.includes('/thumbnail/') && !img.src.includes('/data/'))) {
        img.dataset.cdlAdded = '1';
        return;
      }

      const orig = findOriginal(img);
      if (!orig) {
        img.dataset.cdlAdded = '1';
        return;
      }

      const parent = img.parentElement || img;
      const cs = getComputedStyle(parent);
      if (cs.position === 'static') {
        parent.style.position = 'relative';
        parent.dataset._cdl_posset = '1';
      }

      const btn = document.createElement('button');
      btn.className = 'coomer-dl-btn';
      btn.type = 'button';
      btn.title = 'Download full-size image';
      btn.innerHTML = ICON_SVG;
      btn.addEventListener('click', function (e) {
        e.stopPropagation();
        e.preventDefault();
        const filename = buildFilename(orig, username, postId);
        downloadBinary(orig, filename, btn);
      }, { capture: true });

      parent.appendChild(btn);
      img.dataset.cdlAdded = '1';
    });
  }

  function runForPost() {
    const { username, postId } = getUserAndPost();
    if (username && postId) {
      imageCounter = 0; // reset per post
      addButtonsOnce();
    }
  }

  // Watch for DOM changes
  const mo = new MutationObserver(addButtonsOnce);
  mo.observe(document.body, { childList: true, subtree: true });

  // Watch for URL changes (SPA navigation)
  function checkUrlChange() {
    if (location.href !== lastUrl) {
      lastUrl = location.href;
      runForPost();
    }
  }
  setInterval(checkUrlChange, 500);

  // Initial run
  runForPost();

})();