Render SVG as base64 image and improve scaling

QuickLook.Plugin/QuickLook.Plugin.ImageViewer/Resources/svg2html.html

@@ -19,9 +19,12 @@
             user-select: none;
         }
 
-        #svgWrapper {
+        #svgWrapper img {
             transform-origin: center center;
             transition: transform 0.1s ease-out;
+            display: block;
+            max-width: 100%;
+            max-height: 100%;
         }
     </style>
 </head>

QuickLook.Plugin/QuickLook.Plugin.ImageViewer/Resources/svg2html.js

@@ -1,14 +1,44 @@
 (async function () {
+    function encodeSvgToBase64(svg) {
+        const utf8Bytes = new TextEncoder().encode(svg);
+        let binary = '';
+        for (const byte of utf8Bytes) {
+            binary += String.fromCharCode(byte);
+        }
+        return btoa(binary);
+    }
+
+    function fixSvgSize(svg) {
+        const viewBoxMatch = svg.match(/viewBox\s*=\s*["']?([\d\s\.]+)["']/i);
+        if (!viewBoxMatch) return svg;
+
+        const parts = viewBoxMatch[1].trim().split(/\s+/);
+        if (parts.length !== 4) return svg;
+
+        const width = parseFloat(parts[2]);
+        const height = parseFloat(parts[3]);
+
+        if (/width\s*=/.test(svg) || /height\s*=/.test(svg)) {
+            return svg;
+        }
+
+        return svg.replace(
+            /<svg([^>]*)>/i,
+            `<svg width="${width}" height="${height}"$1>`
+        );
+    }
+
     const wrapper = document.getElementById("svgWrapper");
-
     const svgString = await chrome.webview.hostObjects.external.GetSvgContent();
-
-    wrapper.innerHTML = svgString;
+    const base64 = encodeSvgToBase64(fixSvgSize(svgString));
+    const img = new Image();
+    img.src = `data:image/svg+xml;base64,${base64}`;
+    img.style.transform = "scale(1)";
 
     let scale = 1;
 
     function updateTransform() {
-        wrapper.style.transform = `scale(${scale})`;
+        img.style.transform = `scale(${scale})`;
     }
 
     document.addEventListener("wheel", (e) => {
@@ -16,12 +46,7 @@
 
         const scaleFactor = 1.2;
 
-        if (e.deltaY < 0) {
-            scale *= scaleFactor;
-        } else {
-            scale /= scaleFactor;
-        }
-
+        scale *= (e.deltaY < 0 ? scaleFactor : 1 / scaleFactor);
         updateTransform();
     }, { passive: false });
 
@@ -31,5 +56,6 @@
         updateTransform();
     });
 
+    wrapper.appendChild(img);
     updateTransform();
 })();