naj-download-helper.user.js

// ==UserScript==
// @name        !NAJ: Download Helper
// @namespace   http://a4lg.com/
// @description Adds download control buttons
// @include     https://www.digital.archives.go.jp/DAS/meta/listPhoto*
// @version     1
// @grant       none
// ==/UserScript==
(function() {
  var dtype = document.getElementById("download_type");
  if (!dtype)
    return;
  dtype = dtype.value;
  var nvols = (function() {
    var i = 1;
    while (true) {
      if (!document.getElementById("id_" + i))
        return i - 1;
      ++i;
    }
    return null;
  })();
  var pages = [];
  var totalPages = 0;
  for (var i = 1; i <= nvols; i++) {
    pages.push(parseInt(document.getElementById("max_page_" + i).value));
    totalPages += pages[i - 1];
  }
  if (!maxDownloadCnt) {
    console.log("warning: maxDownloadCnt variable not found. falling back...");
    maxDownloadCnt = 500;
  }
  var downloadSelectionControl = document.createElement("select");
  downloadSelectionControl.addEventListener("change", function(e) {
    var range = e.target.value;
    range = range.split(",");
    var range0 = parseInt(range[0]);
    var range1 = parseInt(range[1]);
    var nvols = parseInt(range[2]);
    for (var i = 1; i <= nvols; i++) {
      document.getElementById("id_" + i.toString()).checked =
        (i >= range0 && i <= range1);
    }
  });
  // 自動ダウンロード用のコントロールを設置
  {
    var controlBox = document.createElement("table");
    controlBox.classList.add("simple-table");
    document.body.insertBefore(controlBox, document.body.childNodes[0]);
    var elem0, elem1;
    elem0 = document.createElement("tbody");
    controlBox.appendChild(elem0);
    elem1 = document.createElement("tr");
    elem0.appendChild(elem1);
    elem0 = document.createElement("th");
    elem0.style.width = "250px";
    elem0.textContent = "自動ダウンロードインデックス";
    elem1.appendChild(elem0);
    elem0 = document.createElement("td");
    elem1.appendChild(elem0);
    elem0.appendChild(downloadSelectionControl);
  }
  var addOption = function(downloadSelectionControl, range0, range1, nvols) {
    var labelFromId = function(n) {
      var l = document.getElementsByTagName("label");
      for (var i = 0; i < l.length; i++) {
        if (l[i].getAttribute("for") === "id_" + n.toString())
          return l[i].textContent;
      }
      return "(不明)";
    };
    var elem = document.createElement("option");
    elem.value = range0.toString() + "," + range1.toString() + "," + nvols.toString();
    downloadSelectionControl.appendChild(elem);
    var label0 = "表紙";
    if (range0 > 1)
      label0 = labelFromId(range0);
    var label1 = label0;
    if (range1 > 1)
      label1 = labelFromId(range1);
    if (range0 == 1 && range1 == nvols)
      elem.textContent = "全部";
    else if (label0 === label1)
      elem.textContent = label0;
    else
      elem.textContent = label0 + " - " + label1;
    elem.textContent = document.getElementById("id_" + range0.toString()).value + " : " + elem.textContent;
  };
  var constructed = false;
  if (totalPages < maxDownloadCnt) {
    addOption(downloadSelectionControl, 1, nvols, nvols);
    constructed = true;
  }
  var isInRange = false;
  var range0 = 1;
  var tmpPages = 0;
  for (var i = 0; i < nvols; i++) {
    if (pages[i] > maxDownloadCnt) {
      if (isInRange) {
        addOption(downloadSelectionControl, range0, i, nvols);
        isInRange = false;
      }
      continue;
    }
    if (!isInRange) {
      isInRange = true;
      range0 = i + 1;
    }
    if (tmpPages + pages[i] > maxDownloadCnt) {
      addOption(downloadSelectionControl, range0, i, nvols);
      tmpPages = 0;
      range0 = i + 1;
    }
    tmpPages += pages[i];
  }
  if (isInRange)
    addOption(downloadSelectionControl, range0, nvols, nvols);
  downloadSelectionControl.selectedIndex = 0;
  downloadSelectionControl.dispatchEvent(new Event("change"));
})();