From f4391796416a998903fcd3e3e0dc7e8cca3614f2 Mon Sep 17 00:00:00 2001
From: gitama2023 <138025603+gitama2023@users.noreply.github.com>
Date: Fri, 7 Jul 2023 16:18:01 +0800
Subject: [PATCH] Added a prompt for users using poor scaling

Added a JavaScript file that detects browser scaling and prompts users when scale is not 100%
---
 javascript/badScaleChecker.js | 108 ++++++++++++++++++++++++++++++++++
 1 file changed, 108 insertions(+)
 create mode 100644 javascript/badScaleChecker.js

diff --git a/javascript/badScaleChecker.js b/javascript/badScaleChecker.js
new file mode 100644
index 00000000..625ad309
--- /dev/null
+++ b/javascript/badScaleChecker.js
@@ -0,0 +1,108 @@
+(function() {
+    var ignore = localStorage.getItem("bad-scale-ignore-it") == "ignore-it";
+
+    function getScale() {
+        var ratio = 0,
+            screen = window.screen,
+            ua = navigator.userAgent.toLowerCase();
+
+        if (window.devicePixelRatio !== undefined) {
+            ratio = window.devicePixelRatio;
+        } else if (~ua.indexOf('msie')) {
+            if (screen.deviceXDPI && screen.logicalXDPI) {
+                ratio = screen.deviceXDPI / screen.logicalXDPI;
+            }
+        } else if (window.outerWidth !== undefined && window.innerWidth !== undefined) {
+            ratio = window.outerWidth / window.innerWidth;
+        }
+
+        return ratio == 0 ? 0 : Math.round(ratio * 100);
+    }
+
+    var showing = false;
+
+    var div = document.createElement("div");
+    div.style.position = "fixed";
+    div.style.top = "0px";
+    div.style.left = "0px";
+    div.style.width = "100vw";
+    div.style.backgroundColor = "firebrick";
+    div.style.textAlign = "center";
+    div.style.zIndex = 99;
+
+    var b = document.createElement("b");
+    b.innerHTML = 'Bad Scale: ??% ';
+
+    div.appendChild(b);
+
+    var note1 = document.createElement("p");
+    note1.innerHTML = "Change your browser or your computer settings!";
+    note1.title = 'Just make sure "computer-scale" * "browser-scale" = 100% ,\n' +
+        "you can keep your computer-scale and only change this page's scale,\n" +
+        "for example: your computer-scale is 125%, just use [\"CTRL\"+\"-\"] to make your browser-scale of this page to 80%.";
+    div.appendChild(note1);
+
+    var note2 = document.createElement("p");
+    note2.innerHTML = " Otherwise, it will cause this page to not function properly!";
+    note2.title = "When you click \"Copy image to: [inpaint sketch]\" in some img2img's tab,\n" +
+        "if scale<100% the canvas will be invisible,\n" +
+        "else if scale>100% this page will take large amount of memory and CPU performance.";
+    div.appendChild(note2);
+
+    var btn = document.createElement("button");
+    btn.innerHTML = "Click here to ignore";
+
+    div.appendChild(btn);
+
+    function tryShowTopBar(scale) {
+        if (showing) return;
+
+        b.innerHTML = 'Bad Scale: ' + scale + '% ';
+
+        var updateScaleTimer = setInterval(function() {
+            var newScale = getScale();
+            b.innerHTML = 'Bad Scale: ' + newScale + '% ';
+            if (newScale == 100) {
+                var p = div.parentNode;
+                if (p != null) p.removeChild(div);
+                showing = false;
+                clearInterval(updateScaleTimer);
+                check();
+            }
+        }, 999);
+
+        btn.onclick = function() {
+            clearInterval(updateScaleTimer);
+            var p = div.parentNode;
+            if (p != null) p.removeChild(div);
+            ignore = true;
+            showing = false;
+            localStorage.setItem("bad-scale-ignore-it", "ignore-it");
+        };
+
+        document.body.appendChild(div);
+    }
+
+    function check() {
+        if (!ignore) {
+            var timer = setInterval(function() {
+                var scale = getScale();
+                if (scale != 100 && !ignore) {
+                    tryShowTopBar(scale);
+                    clearInterval(timer);
+                }
+                if (ignore) {
+                    clearInterval(timer);
+                }
+            }, 999);
+        }
+    }
+
+    if (document.readyState != "complete") {
+        document.onreadystatechange = function() {
+            if (document.readyState != "complete") check();
+        };
+    } else {
+        check();
+    }
+})();