static/js/pager: Run on cache persistence

Run a limited seek interval

1 files changed, 25 insertions, 6 deletions

diff --git a/assets/js/index.js b/assets/js/index.js
index a766e4a..b0f2f84 100644
--- a/assets/js/index.js
+++ b/assets/js/index.js
@@ -5,6 +5,7 @@
         document.cookie.indexOf("disabled");
         return console.log("Pager is disabled due to cookie restrictions.");
     }
+    let seek;
     let settings = {
         pager: {}
     };
@@ -14,8 +15,9 @@
     const scrollRestore = function(url) {
         if (history.scrollRestoration) history.scrollRestoration = "manual";
         settings = JSON.parse(localStorage[key]);
-        const fragment = self.location.hash.slice(1) && document.getElementById(self.location.hash.slice(1));
-        const fragmentInURL = self.location.hash.length > 0;
+        const hash = self.location.hash;
+        const fragment = hash.slice(1) && document.getElementById(hash.slice(1));
+        const fragmentInURL = hash.length > 0;
         if (fragmentInURL && document.body.contains(fragment)) {
             settings["pager"][url] = self.pageYOffset;
             localStorage[key] = JSON.stringify(settings);
@@ -25,7 +27,16 @@
             });
         }
         if (settings["pager"][url] > 0) {
-            return self.scrollTo(0, settings["pager"][url]);
+            self.scrollTo(0, settings["pager"][url]);
+            let i1 = 0;
+            return seek = setInterval(function(position) {
+                i1++;
+                if (i1 > 100) clearInterval(seek);
+                if (document.documentElement.scrollHeight >= position + document.documentElement.clientHeight) {
+                    clearInterval(seek);
+                    self.scrollTo(0, position);
+                }
+            }, 4, settings["pager"][url]);
         }
         settings["pager"][url] = self.pageYOffset;
         localStorage[key] = JSON.stringify(settings);
@@ -48,15 +59,23 @@
         }
     };
     self.addEventListener("DOMContentLoaded", function() {
-        scrollRestore(url);
         self.addEventListener("click", function(event) {
             const up = document.getElementById("top");
             const back = document.getElementById("back");
             reverseTrack(back, up, event);
         });
     });
-    self.addEventListener("hashchange", function() {
-        scrollRestore(url);
+    [
+        "DOMContentLoaded",
+        "pageshow",
+        "hashchange"
+    ].forEach(function(event) {
+        self.addEventListener(event, function(event) {
+            if (event.type === "pageshow") {
+                return event.persisted && self.scrollTo(0, settings["pager"][url]);
+            }
+            scrollRestore(url);
+        });
     });
     [
         "click",