From 7c2fc516bbdc5dd8d5339a63370e2c56e5f9fbb1 Mon Sep 17 00:00:00 2001
From: Bruno Windels <brunow@matrix.org>
Date: Wed, 14 Oct 2020 15:10:32 +0200
Subject: [PATCH] restore last url if not providing a specific one on startup

---
 src/domain/RootViewModel.js | 15 +++++++++------
 src/main.js                 |  9 ++++++++-
 2 files changed, 17 insertions(+), 7 deletions(-)

diff --git a/src/domain/RootViewModel.js b/src/domain/RootViewModel.js
index f81591db..24c810c7 100644
--- a/src/domain/RootViewModel.js
+++ b/src/domain/RootViewModel.js
@@ -35,13 +35,13 @@ export class RootViewModel extends ViewModel {
         this._sessionViewModel = null;
     }
 
-    async load() {
+    async load(lastUrlHash) {
         this.track(this.navigation.observe("login").subscribe(() => this._applyNavigation()));
         this.track(this.navigation.observe("session").subscribe(() => this._applyNavigation()));
-        this._applyNavigation();
+        this._applyNavigation(lastUrlHash);
     }
 
-    async _applyNavigation() {
+    async _applyNavigation(restoreHashIfAtDefault) {
         const isLogin = this.navigation.observe("login").get();
         const sessionId = this.navigation.observe("session").get();
         if (isLogin) {
@@ -58,9 +58,12 @@ export class RootViewModel extends ViewModel {
             }
         } else {
             try {
-                // redirect depending on what sessions are already present
-                const sessionInfos = await this._sessionInfoStorage.getAll();
-                const url = this._urlForSessionInfos(sessionInfos);
+                let url = restoreHashIfAtDefault;
+                if (!url) {
+                    // redirect depending on what sessions are already present
+                    const sessionInfos = await this._sessionInfoStorage.getAll();
+                    url = this._urlForSessionInfos(sessionInfos);
+                }
                 this.urlRouter.history.replaceUrl(url);
                 this.urlRouter.applyUrl(url);
             } catch (err) {
diff --git a/src/main.js b/src/main.js
index 8294aa46..af686d2b 100644
--- a/src/main.js
+++ b/src/main.js
@@ -142,11 +142,18 @@ export async function main(container, paths, legacyExtras) {
             navigation
         });
         window.__brawlViewModel = vm;
-        await vm.load();
+        const lastUrlHash = window.localStorage?.getItem("hydrogen_last_url_hash");
+        await vm.load(lastUrlHash);
         // TODO: replace with platform.createAndMountRootView(vm, container);
         const view = new RootView(vm);
         container.appendChild(view.mount());
+        window.addEventListener("beforeunload", storeUrlHashOnClose);
     } catch(err) {
         console.error(`${err.message}:\n${err.stack}`);
     }
 }
+
+function storeUrlHashOnClose() {
+    window.localStorage?.setItem("hydrogen_last_url_hash", document.location.hash);
+    window.removeEventListener("beforeunload", storeUrlHashOnClose);
+}