⚡ Improved the comments plug-in load function, close #12

static/js/third-party/statistics/firestore.js

@@ -0,0 +1,64 @@
+/* global CONFIG, firebase */
+
+firebase.initializeApp({
+  apiKey   : CONFIG.firestore.apiKey,
+  projectId: CONFIG.firestore.projectId
+});
+
+(function() {
+  const getCount = (doc, increaseCount) => {
+    // IncreaseCount will be false when not in article page
+    return doc.get().then(d => {
+      // Has no data, initialize count
+      let count = d.exists ? d.data().count : 0;
+      // If first view this article
+      if (increaseCount) {
+        // Increase count
+        count++;
+        doc.set({
+          count
+        });
+      }
+      return count;
+    });
+  };
+
+  const appendCountTo = el => {
+    return count => {
+      el.innerText = count;
+    };
+  };
+
+  const db = firebase.firestore();
+  const articles = db.collection(CONFIG.firestore.collection);
+
+  document.addEventListener('page:loaded', () => {
+
+    if (CONFIG.page.isPost) {
+      // Fix issue #118
+      // https://developer.mozilla.org/en-US/docs/Web/API/Node/textContent
+      const title = document.querySelector('.post-title').textContent.trim();
+      const doc = articles.doc(title);
+      let increaseCount = CONFIG.hostname === location.hostname;
+      if (localStorage.getItem(title)) {
+        increaseCount = false;
+      } else {
+        // Mark as visited
+        localStorage.setItem(title, true);
+      }
+      getCount(doc, increaseCount).then(appendCountTo(document.querySelector('.firestore-visitors-count')));
+    } else if (CONFIG.page.isHome) {
+      const promises = [...document.querySelectorAll('.post-title')].map(element => {
+        const title = element.textContent.trim();
+        const doc = articles.doc(title);
+        return getCount(doc);
+      });
+      Promise.all(promises).then(counts => {
+        const metas = document.querySelectorAll('.firestore-visitors-count');
+        counts.forEach((val, idx) => {
+          appendCountTo(metas[idx])(val);
+        });
+      });
+    }
+  });
+})();