implemented opening of external links in new tab

frontend/src/urls.svelte.js

@@ -1,3 +1,22 @@
+const anchor_regex = /<a\s+([^>]*)href=['"]([^'"]+)['"]([^>]*)>/gi;
+
 export function api(rel_path){
     return `${location.protocol}//${location.host.replace('5173','8080')}/api/${rel_path}`;
 }
+
+export function target(code){
+    if (!code) return null;
+    let altered = code;
+
+    let match;
+    while(match = anchor_regex.exec(code)) {
+        const orig = match[0];
+        const href = match[2];
+        if (orig.includes('target=')) continue; // if there is already a target: skip
+        if (!href.includes('://')) continue; // if this is a relative path: skip
+        const anchor = '<a target="_blank" '+orig.substring(3);
+        altered = altered.replaceAll(orig,anchor);
+    }
+
+    return altered;
+}