Insert a Google Docs icon link for viewing PDF/PPT/TIFF with Google Document Viewer.

view-with-gdv.user.js

// ==UserScript==
// @name           View PDF/PPT/TIFF with Google Document Viewer
// @namespace      http://hail2u.net/
// @description    Insert a Google Docs icon for viewing PDF/PPT/TIFF with Google Document Viewer.
// @include        http://*
// @include        https://*
// @exclude        http://docs.google.com/*
// ==/UserScript==

(function () {
  function addLink (d) {
    Array.forEach(d.getElementsByTagName("a"), function (a) {
      if (a.href.match(/\.(pdf|ppt|tiff?)$/i) && !a.href.match(/docs\.google\.com/) && !a.href.match(/q=related:/i)) {
        var gdico = document.createElement("img");
        gdico.setAttribute("src", "http://docs.google.com/favicon.ico");
        gdico.setAttribute("style", "border:none;");
        var gdv = document.createElement("a");
        gdv.setAttribute("href", "http://docs.google.com/gview?url=" + encodeURIComponent(a.href) + "&hl=ja");
        gdv.appendChild(gdico);
        a.parentNode.insertBefore(gdv, a.nextSibling);
        a.parentNode.insertBefore(document.createTextNode(" "), a.nextSibling);
      }
    });
  }

  addLink(document);

  document.body.addEventListener('AutoPagerize_DOMNodeInserted', function (e) {
    addLink(e.target);
  }, false);

  if (typeof LDR !== undefined) {
    var w = unsafeWindow;

    var watcher = {
      callAddLink: function (d) {
        this.cancel();
        addLink(d);
      },

      setup: function (feed) {
        this.cancel();
        var item_count = feed.items.length;
        var d = document.getElementById("right_container");
        var self = this;
        this.timeoutID = setInterval(function () {
          if (d.getElementsByClassName("item").length === item_count) {
            self.callAddLink(d);
          }
        }, 1000);
      },

      cancel: function () {
        if (typeof this.timeoutID === "number") {
          clearInterval(this.timeoutID);
          delete this.timeoutID;
        }
      }
    };

    w.register_hook('after_printfeed', function (feed) {
      watcher.setup(feed);
    });
  }
})();