From bdc8a6b111ce8a69fdb9f88e38f2fe05142f5654 Mon Sep 17 00:00:00 2001
From: schlagmichdoch <schlagmichdoch@users.noreply.github.com>
Date: Thu, 9 Nov 2023 04:49:16 +0100
Subject: [PATCH] Only start loading of deferred assets after UI is ready

---
 public/index.html                             |   9 +-
 public/scripts/main.js                        | 327 ++++++------------
 public/scripts/ui-main.js                     | 173 +++++++++
 .../{main-styles.css => styles-main.css}      |   0
 4 files changed, 273 insertions(+), 236 deletions(-)
 create mode 100644 public/scripts/ui-main.js
 rename public/styles/{main-styles.css => styles-main.css} (100%)

diff --git a/public/index.html b/public/index.html
index b71028d..06ff099 100644
--- a/public/index.html
+++ b/public/index.html
@@ -35,7 +35,7 @@
     <meta property="og:image" content="images/logo_transparent_512x512.png">
     <!-- Resources -->
     <link rel="preload" href="lang/en.json" as="fetch">
-    <link rel="stylesheet" type="text/css" href="styles/main-styles.css">
+    <link rel="stylesheet" type="text/css" href="styles/styles-main.css">
     <link rel="manifest" href="manifest.json">
 </head>
 
@@ -599,13 +599,8 @@
     <script src="scripts/util-main.js"></script>
     <script src="scripts/localization.js"></script>
     <script src="scripts/persistent-storage.js"></script>
+    <script src="scripts/ui-main.js"></script>
     <script src="scripts/main.js"></script>
-    <script defer src="scripts/util.js"></script>
-    <script defer src="scripts/network.js"></script>
-    <script defer src="scripts/ui.js"></script>
-    <script defer src="scripts/qr-code.min.js"></script>
-    <script defer src="scripts/zip.min.js"></script>
-    <script defer src="scripts/no-sleep.min.js"></script>
     <!-- Sounds -->
     <audio id="blop" autobuffer="true">
         <source src="sounds/blop.mp3" type="audio/mpeg">
diff --git a/public/scripts/main.js b/public/scripts/main.js
index 4e412eb..056bb22 100644
--- a/public/scripts/main.js
+++ b/public/scripts/main.js
@@ -1,179 +1,3 @@
-class FooterUI {
-
-    constructor() {
-        this.$displayName = $('display-name');
-        this.$discoveryWrapper = $$('footer .discovery-wrapper');
-
-        // Show "Loading…"
-        this.$displayName.setAttribute('placeholder', this.$displayName.dataset.placeholder);
-
-        this.$displayName.addEventListener('keydown', e => this._onKeyDownDisplayName(e));
-        this.$displayName.addEventListener('keyup', e => this._onKeyUpDisplayName(e));
-        this.$displayName.addEventListener('blur', e => this._saveDisplayName(e.target.innerText));
-
-        Events.on('display-name', e => this._onDisplayName(e.detail.displayName));
-        Events.on('self-display-name-changed', e => this._insertDisplayName(e.detail));
-
-        // Load saved display name on page load
-        Events.on('ws-connected', _ => this._loadSavedDisplayName());
-
-        Events.on('evaluate-footer-badges', _ => this._evaluateFooterBadges());
-    }
-
-    _evaluateFooterBadges() {
-        if (this.$discoveryWrapper.querySelectorAll('div:last-of-type > span[hidden]').length < 2) {
-            this.$discoveryWrapper.classList.remove('row');
-            this.$discoveryWrapper.classList.add('column');
-        }
-        else {
-            this.$discoveryWrapper.classList.remove('column');
-            this.$discoveryWrapper.classList.add('row');
-        }
-        Events.fire('redraw-canvas');
-        Events.fire('fade-in-ui');
-    }
-
-    _loadSavedDisplayName() {
-        this._getSavedDisplayName()
-            .then(displayName => {
-                console.log("Retrieved edited display name:", displayName)
-                if (displayName) {
-                    Events.fire('self-display-name-changed', displayName);
-                }
-            });
-    }
-
-    _onDisplayName(displayName){
-        console.debug(displayName)
-        // set display name
-        this.$displayName.setAttribute('placeholder', displayName);
-    }
-
-
-    _insertDisplayName(displayName) {
-        this.$displayName.textContent = displayName;
-    }
-
-    _onKeyDownDisplayName(e) {
-        if (e.key === "Enter" || e.key === "Escape") {
-            e.preventDefault();
-            e.target.blur();
-        }
-    }
-
-    _onKeyUpDisplayName(e) {
-        // fix for Firefox inserting a linebreak into div on edit which prevents the placeholder from showing automatically when it is empty
-        if (/^(\n|\r|\r\n)$/.test(e.target.innerText)) e.target.innerText = '';
-    }
-
-    async _saveDisplayName(newDisplayName) {
-        newDisplayName = newDisplayName.replace(/(\n|\r|\r\n)/, '')
-        const savedDisplayName = await this._getSavedDisplayName();
-        if (newDisplayName === savedDisplayName) return;
-
-        if (newDisplayName) {
-            PersistentStorage.set('editedDisplayName', newDisplayName)
-                .then(_ => {
-                    Events.fire('notify-user', Localization.getTranslation("notifications.display-name-changed-permanently"));
-                })
-                .catch(_ => {
-                    console.log("This browser does not support IndexedDB. Use localStorage instead.");
-                    localStorage.setItem('editedDisplayName', newDisplayName);
-                    Events.fire('notify-user', Localization.getTranslation("notifications.display-name-changed-temporarily"));
-                })
-                .finally(() => {
-                    Events.fire('self-display-name-changed', newDisplayName);
-                    Events.fire('broadcast-send', {type: 'self-display-name-changed', detail: newDisplayName});
-                });
-        }
-        else {
-            PersistentStorage.delete('editedDisplayName')
-                .catch(_ => {
-                    console.log("This browser does not support IndexedDB. Use localStorage instead.")
-                    localStorage.removeItem('editedDisplayName');
-                })
-                .finally(() => {
-                    Events.fire('notify-user', Localization.getTranslation("notifications.display-name-random-again"));
-                    Events.fire('self-display-name-changed', '');
-                    Events.fire('broadcast-send', {type: 'self-display-name-changed', detail: ''});
-                });
-        }
-    }
-
-    _getSavedDisplayName() {
-        return new Promise((resolve) => {
-            PersistentStorage.get('editedDisplayName')
-                .then(displayName => {
-                    if (!displayName) displayName = "";
-                    resolve(displayName);
-                })
-                .catch(_ => {
-                    let displayName = localStorage.getItem('editedDisplayName');
-                    if (!displayName) displayName = "";
-                    resolve(displayName);
-                })
-        });
-    }
-}
-
-class BackgroundCanvas {
-    constructor() {
-        this.c = $$('canvas');
-        this.cCtx = this.c.getContext('2d');
-        this.$footer = $$('footer');
-
-        // fade-in on load
-        Events.on('fade-in-ui', _ => this._fadeIn());
-
-        // redraw canvas
-        Events.on('resize', _ => this.init());
-        Events.on('redraw-canvas', _ => this.init());
-        Events.on('translation-loaded', _ => this.init());
-    }
-
-    _fadeIn() {
-        this.c.classList.remove('opacity-0');
-    }
-
-    init() {
-        let oldW = this.w;
-        let oldH = this.h;
-        let oldOffset = this.offset
-        this.w = document.documentElement.clientWidth;
-        this.h = document.documentElement.clientHeight;
-        this.offset = this.$footer.offsetHeight - 27;
-        if (this.h >= 800) this.offset += 10;
-
-        if (oldW === this.w && oldH === this.h && oldOffset === this.offset) return; // nothing has changed
-
-        this.c.width = this.w;
-        this.c.height = this.h;
-        this.x0 = this.w / 2;
-        this.y0 = this.h - this.offset;
-        this.dw = Math.round(Math.max(this.w, this.h, 1000) / 13);
-
-        this.drawCircles(this.cCtx);
-    }
-
-
-    drawCircle(ctx, radius) {
-        ctx.beginPath();
-        ctx.lineWidth = 2;
-        let opacity = Math.max(0, 0.3 * (1 - 1 * radius / Math.max(this.w, this.h)));
-        ctx.strokeStyle = `rgba(128, 128, 128, ${opacity})`;
-        ctx.arc(this.x0, this.y0, radius, 0, 2 * Math.PI);
-        ctx.stroke();
-    }
-
-    drawCircles(ctx) {
-        ctx.clearRect(0, 0, this.w, this.h);
-        for (let i = 0; i < 13; i++) {
-            this.drawCircle(ctx, this.dw * i + 33 + 66);
-        }
-    }
-}
-
-
 class PairDrop {
     constructor() {
         this.$header = $$('header.opacity-0');
@@ -186,6 +10,12 @@ class PairDrop {
 
         this.$head = $$('head');
 
+        this.$installBtn = $('install');
+
+        this.registerServiceWorker();
+
+        Events.on('beforeinstallprompt', e => this.onPwaInstallable(e));
+
         Events.on('initial-translation-loaded', _ => {
             const backgroundCanvas = new BackgroundCanvas();
             const footerUI = new FooterUI();
@@ -196,11 +26,34 @@ class PairDrop {
             // Evaluate UI elements and fade in UI
             this.evaluateUI();
 
-            // Load delayed assets
+            // Load deferred assets
             this.loadDeferredAssets();
         });
     }
 
+    registerServiceWorker() {
+        if ('serviceWorker' in navigator) {
+            navigator.serviceWorker
+                .register('/service-worker.js')
+                .then(serviceWorker => {
+                    console.log('Service Worker registered');
+                    window.serviceWorker = serviceWorker
+                });
+        }
+    }
+
+    onPwaInstallable(e) {
+        if (!window.matchMedia('(display-mode: minimal-ui)').matches) {
+            // only display install btn when not installed
+            this.$installBtn.removeAttribute('hidden');
+            this.$installBtn.addEventListener('click', () => {
+                this.$installBtn.setAttribute('hidden', true);
+                e.prompt();
+            });
+        }
+        return e.preventDefault();
+    }
+
     evaluateUI() {
         // Check whether notification permissions have already been granted
         if ('Notification' in window && Notification.permission !== 'granted') {
@@ -236,14 +89,20 @@ class PairDrop {
     }
 
     loadDeferredAssets() {
-        console.debug("Load deferred assets");
-        if (document.readyState === "loading") {
-            // Loading hasn't finished yet
-            Events.on('DOMContentLoaded', _ => this.hydrate());
-        } else {
-            // `DOMContentLoaded` has already fired
-            this.hydrate();
-        }
+        console.log("Load deferred assets");
+        this.deferredStyles = [
+            "styles/deferred-styles.css"
+        ];
+        this.deferredScripts = [
+            "scripts/util.js",
+            "scripts/network.js",
+            "scripts/ui.js",
+            "scripts/qr-code.min.js",
+            "scripts/zip.min.js",
+            "scripts/no-sleep.min.js"
+        ];
+        this.deferredStyles.forEach(url => this.loadStyleSheet(url, _ => this.onStyleLoaded(url)))
+        this.deferredScripts.forEach(url => this.loadScript(url, _ => this.onScriptLoaded(url)))
     }
 
     loadStyleSheet(url, callback) {
@@ -255,53 +114,63 @@ class PairDrop {
         this.$head.appendChild(stylesheet);
     }
 
+    loadScript(url, callback) {
+        let script = document.createElement("script");
+        script.src = url;
+        script.onload = callback;
+        document.body.appendChild(script);
+    }
+
+    onStyleLoaded(url) {
+        // remove entry from array
+        const index = this.deferredStyles.indexOf(url);
+        if (index !== -1) {
+            this.deferredStyles.splice(index, 1);
+        }
+        this.onAssetLoaded();
+    }
+
+    onScriptLoaded(url) {
+        // remove entry from array
+        const index = this.deferredScripts.indexOf(url);
+        if (index !== -1) {
+            this.deferredScripts.splice(index, 1);
+        }
+        this.onAssetLoaded();
+    }
+
+    onAssetLoaded() {
+        if (this.deferredScripts.length || this.deferredStyles.length) return;
+
+        console.log("Loading of deferred assets completed. Start UI hydration.");
+
+        this.hydrate();
+    }
+
     hydrate() {
-        this.loadStyleSheet('styles/deferred-styles.css', _ => {
-                const peersUI = new PeersUI();
-                const languageSelectDialog = new LanguageSelectDialog();
-                const receiveFileDialog = new ReceiveFileDialog();
-                const receiveRequestDialog = new ReceiveRequestDialog();
-                const sendTextDialog = new SendTextDialog();
-                const receiveTextDialog = new ReceiveTextDialog();
-                const pairDeviceDialog = new PairDeviceDialog();
-                const clearDevicesDialog = new EditPairedDevicesDialog();
-                const publicRoomDialog = new PublicRoomDialog();
-                const base64ZipDialog = new Base64ZipDialog();
-                const toast = new Toast();
-                const notifications = new Notifications();
-                const networkStatusUI = new NetworkStatusUI();
-                const webShareTargetUI = new WebShareTargetUI();
-                const webFileHandlersUI = new WebFileHandlersUI();
-                const noSleepUI = new NoSleepUI();
-                const broadCast = new BrowserTabsConnector();
-                const server = new ServerConnection();
-                const peers = new PeersManager(server);
-        });
+        const peersUI = new PeersUI();
+        const languageSelectDialog = new LanguageSelectDialog();
+        const receiveFileDialog = new ReceiveFileDialog();
+        const receiveRequestDialog = new ReceiveRequestDialog();
+        const sendTextDialog = new SendTextDialog();
+        const receiveTextDialog = new ReceiveTextDialog();
+        const pairDeviceDialog = new PairDeviceDialog();
+        const clearDevicesDialog = new EditPairedDevicesDialog();
+        const publicRoomDialog = new PublicRoomDialog();
+        const base64ZipDialog = new Base64ZipDialog();
+        const toast = new Toast();
+        const notifications = new Notifications();
+        const networkStatusUI = new NetworkStatusUI();
+        const webShareTargetUI = new WebShareTargetUI();
+        const webFileHandlersUI = new WebFileHandlersUI();
+        const noSleepUI = new NoSleepUI();
+        const broadCast = new BrowserTabsConnector();
+        const server = new ServerConnection();
+        const peers = new PeersManager(server);
+        console.log("UI hydrated.")
     }
 }
 
 const persistentStorage = new PersistentStorage();
 const pairDrop = new PairDrop();
-const localization = new Localization();
-
-if ('serviceWorker' in navigator) {
-    navigator.serviceWorker
-        .register('/service-worker.js')
-        .then(serviceWorker => {
-            console.log('Service Worker registered');
-            window.serviceWorker = serviceWorker
-        });
-}
-
-window.addEventListener('beforeinstallprompt', installEvent => {
-    if (!window.matchMedia('(display-mode: minimal-ui)').matches) {
-        // only display install btn when not installed
-        const installBtn = $('install')
-        installBtn.removeAttribute('hidden');
-        installBtn.addEventListener('click', () => {
-            installBtn.setAttribute('hidden', true);
-            installEvent.prompt();
-        });
-    }
-    return installEvent.preventDefault();
-});
\ No newline at end of file
+const localization = new Localization();
\ No newline at end of file
diff --git a/public/scripts/ui-main.js b/public/scripts/ui-main.js
new file mode 100644
index 0000000..a9c9f6d
--- /dev/null
+++ b/public/scripts/ui-main.js
@@ -0,0 +1,173 @@
+class FooterUI {
+
+    constructor() {
+        this.$displayName = $('display-name');
+        this.$discoveryWrapper = $$('footer .discovery-wrapper');
+
+        // Show "Loading…"
+        this.$displayName.setAttribute('placeholder', this.$displayName.dataset.placeholder);
+
+        this.$displayName.addEventListener('keydown', e => this._onKeyDownDisplayName(e));
+        this.$displayName.addEventListener('keyup', e => this._onKeyUpDisplayName(e));
+        this.$displayName.addEventListener('blur', e => this._saveDisplayName(e.target.innerText));
+
+        Events.on('display-name', e => this._onDisplayName(e.detail.displayName));
+        Events.on('self-display-name-changed', e => this._insertDisplayName(e.detail));
+
+        // Load saved display name on page load
+        Events.on('ws-connected', _ => this._loadSavedDisplayName());
+
+        Events.on('evaluate-footer-badges', _ => this._evaluateFooterBadges());
+    }
+
+    _evaluateFooterBadges() {
+        if (this.$discoveryWrapper.querySelectorAll('div:last-of-type > span[hidden]').length < 2) {
+            this.$discoveryWrapper.classList.remove('row');
+            this.$discoveryWrapper.classList.add('column');
+        }
+        else {
+            this.$discoveryWrapper.classList.remove('column');
+            this.$discoveryWrapper.classList.add('row');
+        }
+        Events.fire('redraw-canvas');
+        Events.fire('fade-in-ui');
+    }
+
+    _loadSavedDisplayName() {
+        this._getSavedDisplayName()
+            .then(displayName => {
+                console.log("Retrieved edited display name:", displayName)
+                if (displayName) {
+                    Events.fire('self-display-name-changed', displayName);
+                }
+            });
+    }
+
+    _onDisplayName(displayName){
+        // set display name
+        this.$displayName.setAttribute('placeholder', displayName);
+    }
+
+
+    _insertDisplayName(displayName) {
+        this.$displayName.textContent = displayName;
+    }
+
+    _onKeyDownDisplayName(e) {
+        if (e.key === "Enter" || e.key === "Escape") {
+            e.preventDefault();
+            e.target.blur();
+        }
+    }
+
+    _onKeyUpDisplayName(e) {
+        // fix for Firefox inserting a linebreak into div on edit which prevents the placeholder from showing automatically when it is empty
+        if (/^(\n|\r|\r\n)$/.test(e.target.innerText)) e.target.innerText = '';
+    }
+
+    async _saveDisplayName(newDisplayName) {
+        newDisplayName = newDisplayName.replace(/(\n|\r|\r\n)/, '')
+        const savedDisplayName = await this._getSavedDisplayName();
+        if (newDisplayName === savedDisplayName) return;
+
+        if (newDisplayName) {
+            PersistentStorage.set('editedDisplayName', newDisplayName)
+                .then(_ => {
+                    Events.fire('notify-user', Localization.getTranslation("notifications.display-name-changed-permanently"));
+                })
+                .catch(_ => {
+                    console.log("This browser does not support IndexedDB. Use localStorage instead.");
+                    localStorage.setItem('editedDisplayName', newDisplayName);
+                    Events.fire('notify-user', Localization.getTranslation("notifications.display-name-changed-temporarily"));
+                })
+                .finally(() => {
+                    Events.fire('self-display-name-changed', newDisplayName);
+                    Events.fire('broadcast-send', {type: 'self-display-name-changed', detail: newDisplayName});
+                });
+        }
+        else {
+            PersistentStorage.delete('editedDisplayName')
+                .catch(_ => {
+                    console.log("This browser does not support IndexedDB. Use localStorage instead.")
+                    localStorage.removeItem('editedDisplayName');
+                })
+                .finally(() => {
+                    Events.fire('notify-user', Localization.getTranslation("notifications.display-name-random-again"));
+                    Events.fire('self-display-name-changed', '');
+                    Events.fire('broadcast-send', {type: 'self-display-name-changed', detail: ''});
+                });
+        }
+    }
+
+    _getSavedDisplayName() {
+        return new Promise((resolve) => {
+            PersistentStorage.get('editedDisplayName')
+                .then(displayName => {
+                    if (!displayName) displayName = "";
+                    resolve(displayName);
+                })
+                .catch(_ => {
+                    let displayName = localStorage.getItem('editedDisplayName');
+                    if (!displayName) displayName = "";
+                    resolve(displayName);
+                })
+        });
+    }
+}
+
+class BackgroundCanvas {
+    constructor() {
+        this.c = $$('canvas');
+        this.cCtx = this.c.getContext('2d');
+        this.$footer = $$('footer');
+
+        // fade-in on load
+        Events.on('fade-in-ui', _ => this._fadeIn());
+
+        // redraw canvas
+        Events.on('resize', _ => this.init());
+        Events.on('redraw-canvas', _ => this.init());
+        Events.on('translation-loaded', _ => this.init());
+    }
+
+    _fadeIn() {
+        this.c.classList.remove('opacity-0');
+    }
+
+    init() {
+        let oldW = this.w;
+        let oldH = this.h;
+        let oldOffset = this.offset
+        this.w = document.documentElement.clientWidth;
+        this.h = document.documentElement.clientHeight;
+        this.offset = this.$footer.offsetHeight - 27;
+        if (this.h >= 800) this.offset += 10;
+
+        if (oldW === this.w && oldH === this.h && oldOffset === this.offset) return; // nothing has changed
+
+        this.c.width = this.w;
+        this.c.height = this.h;
+        this.x0 = this.w / 2;
+        this.y0 = this.h - this.offset;
+        this.dw = Math.round(Math.max(this.w, this.h, 1000) / 13);
+
+        this.drawCircles(this.cCtx);
+    }
+
+
+    drawCircle(ctx, radius) {
+        ctx.beginPath();
+        ctx.lineWidth = 2;
+        let opacity = Math.max(0, 0.3 * (1 - 1 * radius / Math.max(this.w, this.h)));
+        ctx.strokeStyle = `rgba(128, 128, 128, ${opacity})`;
+        ctx.arc(this.x0, this.y0, radius, 0, 2 * Math.PI);
+        ctx.stroke();
+    }
+
+    drawCircles(ctx) {
+        ctx.clearRect(0, 0, this.w, this.h);
+        for (let i = 0; i < 13; i++) {
+            this.drawCircle(ctx, this.dw * i + 33 + 66);
+        }
+    }
+}
\ No newline at end of file
diff --git a/public/styles/main-styles.css b/public/styles/styles-main.css
similarity index 100%
rename from public/styles/main-styles.css
rename to public/styles/styles-main.css