Exclude JS source code from the output

_javascript/utils/category-collapse.js

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+/*
+ * Tab 'Categories' expand/close effect.
+ */
+
+$(function() {
+  const childPrefix = "l_";
+  const parentPrefix = "h_";
+  const collapse = $(".collapse");
+
+  /* close up top-category */
+  collapse.on("hide.bs.collapse", function () { /* Bootstrap collapse events. */
+    const parentId = parentPrefix + $(this).attr("id").substring(childPrefix.length);
+    if (parentId) {
+      $(`#${parentId} .far.fa-folder-open`).attr("class", "far fa-folder fa-fw");
+      $(`#${parentId} i.fas`).addClass("rotate");
+      $(`#${parentId}`).removeClass("hide-border-bottom");
+    }
+  });
+
+  /* expand the top category */
+  collapse.on("show.bs.collapse", function() {
+    const parentId = parentPrefix + $(this).attr("id").substring(childPrefix.length);
+    if (parentId) {
+      $(`#${parentId} .far.fa-folder`).attr("class", "far fa-folder-open fa-fw");
+      $(`#${parentId} i.fas`).removeClass("rotate");
+      $(`#${parentId}`).addClass("hide-border-bottom");
+    }
+  });
+
+});

_javascript/utils/lang-badge.js

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+/**
+ *  Add language indicator to code snippets
+ */
+
+$(function() {
+  const prefix = "language-";
+  const regex = new RegExp(`^${prefix}([a-z])+$`);
+
+  $(`div[class^=${prefix}`).each(function() {
+    let classes = $(this).attr("class").split(" ");
+
+    classes.forEach((_class) => {
+      if (regex.test(_class)) {
+        let lang = _class.substring(prefix.length);
+        $(this).attr("lang", `${lang}`);
+      }
+    });
+
+  });
+});

_javascript/utils/pageviews.js

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+/*
+ * Count page views form GA or local cache file.
+ *
+ * Dependencies:
+ *   - jQuery
+ *   - countUp.js <https://github.com/inorganik/countUp.js>
+ */
+
+const getInitStatus = (function () {
+  let hasInit = false;
+  return () => {
+    let ret = hasInit;
+    if (!hasInit) {
+      hasInit = true;
+    }
+    return ret;
+  };
+}());
+
+const PvOpts = (function () {
+  function getContent(selector) {
+    return $(selector).attr("content");
+  }
+
+  function hasContent(selector) {
+    let content = getContent(selector);
+    return (typeof content !== "undefined" && content !== false);
+  }
+
+  return {
+    getProxyMeta() {
+      return getContent("meta[name=pv-proxy-endpoint]");
+    },
+    getLocalMeta() {
+      return getContent("meta[name=pv-cache-path]");
+    },
+    hasProxyMeta() {
+      return hasContent("meta[name=pv-proxy-endpoint]");
+    },
+    hasLocalMeta() {
+      return hasContent("meta[name=pv-cache-path]");
+    }
+  };
+
+}());
+
+const PvStorage = (function () {
+  const Keys = {
+    KEY_PV: "pv",
+    KEY_PV_SRC: "pv_src",
+    KEY_CREATION: "pv_created_date"
+  };
+
+  const Source = {
+    LOCAL: "same-origin",
+    PROXY: "cors"
+  };
+
+  function get(key) {
+    return localStorage.getItem(key);
+  }
+
+  function set(key, val) {
+    localStorage.setItem(key, val);
+  }
+
+  function saveCache(pv, src) {
+    set(Keys.KEY_PV, pv);
+    set(Keys.KEY_PV_SRC, src);
+    set(Keys.KEY_CREATION, new Date().toJSON());
+  }
+
+  return {
+    keysCount() {
+      return Object.keys(Keys).length;
+    },
+    hasCache() {
+      return (localStorage.getItem(Keys.KEY_PV) !== null);
+    },
+    getCache() {
+      return JSON.parse(localStorage.getItem(Keys.KEY_PV));
+    },
+    saveLocalCache(pv) {
+      saveCache(pv, Source.LOCAL);
+    },
+    saveProxyCache(pv) {
+      saveCache(pv, Source.PROXY);
+    },
+    isExpired() {
+      let date = new Date(get(Keys.KEY_CREATION));
+      date.setHours(date.getHours() + 1);   // per hour
+      return Date.now() >= date.getTime();
+    },
+    isFromLocal() {
+      return get(Keys.KEY_PV_SRC) === Source.LOCAL;
+    },
+    isFromProxy() {
+      return get(Keys.KEY_PV_SRC) === Source.PROXY;
+    },
+    newerThan(pv) {
+      return PvStorage.getCache().totalsForAllResults["ga:pageviews"] > pv.totalsForAllResults["ga:pageviews"];
+    },
+    inspectKeys() {
+      if (localStorage.length !== PvStorage.keysCount()) {
+        localStorage.clear();
+        return;
+      }
+
+      for(let i = 0; i < localStorage.length; i++){
+        const key = localStorage.key(i);
+        switch (key) {
+          case Keys.KEY_PV:
+          case Keys.KEY_PV_SRC:
+          case Keys.KEY_CREATION:
+            break;
+          default:
+            localStorage.clear();
+            return;
+        }
+      }
+    }
+  };
+}()); /* PvStorage */
+
+function countUp(min, max, destId) {
+  if (min < max) {
+    let numAnim = new CountUp(destId, min, max);
+    if (!numAnim.error) {
+      numAnim.start();
+    } else {
+      console.error(numAnim.error);
+    }
+  }
+}
+
+function countPV(path, rows) {
+  let count = 0;
+
+  if (typeof rows !== "undefined" ) {
+    for (let i = 0; i < rows.length; ++i) {
+      const gaPath = rows[parseInt(i, 10)][0];
+      if (gaPath === path) { /* path format see: site.permalink */
+        count += parseInt(rows[parseInt(i, 10)][1], 10);
+        break;
+      }
+    }
+  }
+
+  return count;
+}
+
+function tacklePV(rows, path, elem, hasInit) {
+  let count = countPV(path, rows);
+  count = (count === 0 ? 1 : count);
+
+  if (!hasInit) {
+    elem.text(new Intl.NumberFormat().format(count));
+  } else {
+    const initCount = parseInt(elem.text().replace(/,/g, ""), 10);
+    if (count > initCount) {
+      countUp(initCount, count, elem.attr("id"));
+    }
+  }
+}
+
+function displayPageviews(data) {
+  if (typeof data === "undefined") {
+    return;
+  }
+
+  let hasInit = getInitStatus();
+  const rows = data.rows; /* could be undefined */
+
+  if ($("#post-list").length > 0) { /* the Home page */
+    $(".post-preview").each(function() {
+      const path = $(this).find("a").attr("href");
+      tacklePV(rows, path, $(this).find(".pageviews"), hasInit);
+    });
+
+  } else if ($(".post").length > 0) { /* the post */
+    const path = window.location.pathname;
+    tacklePV(rows, path, $("#pv"), hasInit);
+  }
+}
+
+function fetchProxyPageviews() {
+  if (PvOpts.hasProxyMeta()) {
+    $.ajax({
+      type: "GET",
+      url: PvOpts.getProxyMeta(),
+      dataType: "jsonp",
+      jsonpCallback: "displayPageviews",
+      success: (data) => {
+        PvStorage.saveProxyCache(JSON.stringify(data));
+      },
+      error: (jqXHR, textStatus, errorThrown) => {
+        console.log("Failed to load pageviews from proxy server: " + errorThrown);
+      }
+    });
+  }
+}
+
+function fetchLocalPageviews(hasCache = false) {
+  return fetch(PvOpts.getLocalMeta())
+    .then(response => response.json())
+    .then(data => {
+      if (hasCache) {
+        // The cache from the proxy will sometimes be more recent than the local one
+        if (PvStorage.isFromProxy() && PvStorage.newerThan(data)) {
+          return;
+        }
+      }
+      displayPageviews(data);
+      PvStorage.saveLocalCache(JSON.stringify(data));
+    });
+}
+
+$(function() {
+  if ($(".pageviews").length <= 0) {
+    return;
+  }
+
+  PvStorage.inspectKeys();
+
+  if (PvStorage.hasCache()) {
+    displayPageviews(PvStorage.getCache());
+
+    if (PvStorage.isExpired()) {
+      if (PvOpts.hasLocalMeta()) {
+        fetchLocalPageviews(true).then(fetchProxyPageviews);
+      } else {
+        fetchProxyPageviews();
+      }
+
+    } else {
+      if (PvStorage.isFromLocal()) {
+        fetchProxyPageviews();
+      }
+    }
+
+  } else { // no cached
+
+    if (PvOpts.hasLocalMeta()) {
+      fetchLocalPageviews().then(fetchProxyPageviews);
+    } else {
+      fetchProxyPageviews();
+    }
+  }
+
+});

_javascript/utils/smooth-scroll.js

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+/*
+  Safari doesn't support CSS `scroll-behavior: smooth`,
+  so here is a compatible solution for all browser to smooth scrolling
+
+  See: <https://css-tricks.com/snippets/jquery/smooth-scrolling/>
+
+  Warning: It must be called after all `<a>` tags (e.g., the dynamic TOC) are ready.
+*/
+
+$(function() {
+  $("a[href*='#']")
+    .not("[href='#']")
+    .not("[href='#0']")
+    .click(function(event) {
+
+      if (this.pathname.replace(/^\//, "") === location.pathname.replace(/^\//, "")) {
+        if (location.hostname === this.hostname) {
+
+          const REM = 16; /* 16px */
+
+          const hash = decodeURI(this.hash);
+          let isFnRef = RegExp(/^#fnref:/).test(hash);
+          let isFn = RegExp(/^#fn:/).test(hash);
+          let selector = hash.includes(":") ? hash.replace(/\:/, "\\:") : hash;
+          let target = $(selector);
+
+          if (target.length) {
+            event.preventDefault();
+
+            if (history.pushState) { /* add hash to URL */
+              history.pushState(null, null, hash);
+            }
+
+            let curOffset = $(this).offset().top;
+            let destOffset = target.offset().top;
+            const scrollUp = (destOffset < curOffset);
+            const topbarHeight = $("#topbar-wrapper").outerHeight();
+
+            if (scrollUp && isFnRef) {
+              /* Avoid the top-bar covering `fnref` when scrolling up
+                because `fnref` has no `%anchor`(see: module.scss) style. */
+              destOffset -= (topbarHeight + REM / 2);
+            }
+
+            $("html,body").animate({
+              scrollTop: destOffset
+            }, 800, () => {
+
+              const $target = $(target);
+              $target.focus();
+
+              const SCROLL_MARK = "scroll-focus";
+
+              /* clean up old scroll mark */
+              if ($(`[${SCROLL_MARK}=true]`).length) {
+                $(`[${SCROLL_MARK}=true]`).attr(SCROLL_MARK, false);
+              }
+
+              /* Clean :target links */
+              if ($(":target").length) { /* element that visited by the URL with hash */
+                $(":target").attr(SCROLL_MARK, false);
+              }
+
+              /* set scroll mark to footnotes */
+              if (isFn || isFnRef) {
+                $target.attr(SCROLL_MARK, true);
+              }
+
+              if ($target.is(":focus")) { /* Checking if the target was focused */
+                return false;
+              } else {
+                $target.attr("tabindex", "-1"); /* Adding tabindex for elements not focusable */
+                $target.focus(); /* Set focus again */
+              }
+            });
+          }
+        }
+      }
+
+    }); /* click() */
+});

_javascript/utils/timeago.js

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+/*
+ * Calculate the Timeago
+ */
+
+$(function() {
+
+  const timeagoElem = $(".timeago");
+
+  let toRefresh = timeagoElem.length;
+
+  let intervalId = void 0;
+
+  function timeago(iso, preposition) {
+    let now = new Date();
+    let past = new Date(iso);
+    let prep = (typeof preposition !== "undefined" ? `${preposition} ` : "");
+
+    if (past.getFullYear() !== now.getFullYear()) {
+      toRefresh -= 1;
+      return prep + past.toLocaleString("en-US", {
+        year: "numeric",
+        month: "short",
+        day: "numeric"
+      });
+    }
+
+    if (past.getMonth() !== now.getMonth()) {
+      toRefresh -= 1;
+      return prep + past.toLocaleString("en-US", {
+        month: "short",
+        day: "numeric"
+      });
+    }
+
+    let seconds = Math.floor((now - past) / 1000);
+
+    let day = Math.floor(seconds / 86400);
+    if (day >= 1) {
+      toRefresh -= 1;
+      return day + " day" + (day > 1 ? "s" : "") + " ago";
+    }
+
+    let hour = Math.floor(seconds / 3600);
+    if (hour >= 1) {
+      return hour + " hour" + (hour > 1 ? "s" : "") + " ago";
+    }
+
+    let minute = Math.floor(seconds / 60);
+    if (minute >= 1) {
+      return minute + " minute" + (minute > 1 ? "s" : "") + " ago";
+    }
+
+    return "just now";
+  }
+
+  function updateTimeago() {
+    $(".timeago").each(function() {
+      if ($(this).children("i").length > 0) {
+        let node = $(this).children("i");
+        let date = node.text(); /* ISO Date: "YYYY-MM-DDTHH:MM:SSZ" */
+        $(this).text(timeago(date, $(this).attr("prep")));
+        $(this).append(node);
+      }
+    });
+
+    if (toRefresh === 0 && typeof intervalId !== "undefined") {
+      clearInterval(intervalId); /* stop interval */
+    }
+    return toRefresh;
+  }
+
+  if (toRefresh === 0) {
+    return;
+  }
+
+  if (updateTimeago() > 0) { /* run immediately */
+    intervalId = setInterval(updateTimeago, 60000); /* run every minute */
+  }
+
+});