hnim.js

   1 (() => {
   2   const comments = document.querySelectorAll("tr.comtr");
   3   const items = document.querySelectorAll("table.itemlist tr.athing");
   4   const morelink = document.querySelectorAll("a.morelink");
   5
   6   const elements = [
   7     ...Array.from(items),
   8     ...Array.from(comments),
   9     ...Array.from(morelink),
  10   ];
  11
  12   let elementsIndex = 0;
  13   let selectedElement = elements[elementsIndex];
  14   selectedElement.style.outline = '1px dashed black';
  15
  16   const visible = (element) => {
  17     let bounds = element.getBoundingClientRect();
  18     return bounds.top >= 0 && bounds.bottom <= window.innerHeight;
  19   }
  20
  21   const changeWithVisibleCallback = (comment, callback) => {
  22     if (comment == null) {
  23       return;
  24     }
  25     selectedElement.style.outline = '';
  26     selectedElement = comment;
  27     selectedElement.style.outline = '1px dashed black';
  28     while (!visible(comment)) {
  29       callback();
  30     }
  31   }
  32
  33   const change = (comment) => {
  34     elementsIndex = elements.indexOf(comment);
  35     changeWithVisibleCallback(comment, () => {});
  36   }
  37
  38   // Curry callback for moving downpage
  39   const changeDownpage = () => {
  40     elementsIndex = Math.min(elementsIndex + 1, elements.length);
  41     changeWithVisibleCallback(elements[elementsIndex], () => {window.scrollTo(0, window.scrollY + selectedElement.offsetHeight)});
  42   }
  43
  44   // Curry callback for moving up page
  45   const changeUppage = () => {
  46     elementsIndex = Math.max(elementsIndex - 1, 0);
  47     changeWithVisibleCallback(elements[elementsIndex], () => {window.scrollTo(0, window.scrollY - selectedElement.offsetHeight)});
  48   }
  49
  50   document.addEventListener("click", (e) => {
  51     change(e.target.closest("tr.athing"));
  52   })
  53   document.addEventListener("keydown", (e) => {
  54     if (e.isComposing) {
  55       return;
  56     }
  57     switch (e.key) {
  58       case "j":
  59         do {
  60           changeDownpage();
  61         } while (selectedElement.classList.contains("noshow"));
  62         break;
  63       case "k":
  64         do {
  65           changeUppage();
  66         } while (selectedElement.classList.contains("noshow"));
  67         break;
  68       case "m":
  69       case "Enter":
  70         let togg = selectedElement.querySelector(".togg");
  71         if (togg) {
  72           togg.click();
  73         }
  74         else if (elementsIndex == elements.length - 1) {
  75           selectedElement.click();
  76         }
  77         break;
  78       case "o":
  79         window.location.href = "https://news.ycombinator.com/item?id=" + selectedElement.id;
  80       case "p":
  81         while (selectedElement.querySelector("td.ind").firstElementChild.width != 0) {
  82           changeUppage();
  83         }
  84         break;
  85       default:
  86         //noop
  87     }
  88   })
  89 })();