🐛 Fixed infinitescroll when a paged url is loaded directly (#447)

closes #445
- added an fn to sanitize the pathname, that might include a pagination url
- fixed an issue, where the request would still be made if the current page is bigger than max pages
- added comments

assets/js/infinitescroll.js

@@ -1,3 +1,5 @@
+/* global maxPages */
+
 // Code snippet inspired by https://github.com/douglasrodrigues5/ghost-blog-infinite-scroll
 $(function ($) {
     var currentPage = 1;
@@ -13,9 +15,6 @@ $(function ($) {
     var lastWindowHeight = window.innerHeight;
     var lastDocumentHeight = $document.height();
 
-    // remove hash params from pathname
-    pathname = pathname.replace(/#(.*)$/g, '').replace('/\//g', '/');
-
     function onScroll() {
         lastScrollY = window.scrollY;
         requestTick();
@@ -34,7 +33,29 @@ $(function ($) {
         ticking = true;
     }
 
+    function sanitizePathname(path) {
+        var paginationRegex = /(?:page\/)(\d)(?:\/)$/i;
+
+        // remove hash params from path
+        path = path.replace(/#(.*)$/g, '').replace('////g', '/');
+
+        // remove pagination from the path and replace the current pages
+        // with the actual requested page. E. g. `/page/3/` indicates that
+        // the user actually requested page 3, so we should request page 4
+        // next, unless it's the last page already.
+        if (path.match(paginationRegex)) {
+            currentPage = parseInt(path.match(paginationRegex)[1]);
+
+            path = path.replace(paginationRegex, '');
+        }
+
+        return path;
+    }
+
     function infiniteScroll() {
+        // sanitize the pathname from possible pagination or hash params
+        pathname = sanitizePathname(pathname);
+
         // return if already loading
         if (isLoading) {
             return;
@@ -46,15 +67,22 @@ $(function ($) {
             return;
         }
 
-        // return if currentPage is the last page already
-        if (currentPage === maxPages) {
+        /**
+        * maxPages is defined in default.hbs and is the value
+        * of the amount of pagination pages.
+        * If we reached the last page or are past it,
+        * we return and disable the listeners.
+        */
+        if (currentPage >= maxPages) {
+            window.removeEventListener('scroll', onScroll, {passive: true});
+            window.removeEventListener('resize', onResize);
             return;
         }
 
         isLoading = true;
 
         // next page
-        currentPage++;
+        currentPage += 1;
 
         // Load more
         var nextPage = pathname + 'page/' + currentPage + '/';