import/restore: automatically detect prefix from the full path

dashboard/src/utils.js

@@ -739,6 +739,25 @@ function getColor(numOfSteps, step) {
   return `hsl(${deg*step} 70% 50%)`;
 }
 
+// split path into a prefix (anything before timestamp or 'snapshot') and the remaining remotePath
+function parseFullBackupPath(fullPath) {
+    const parts = fullPath.split('/');
+    const timestampRegex = /^\d{4}-\d{2}-\d{2}-\d{6}-\d{3}$/; // timestamp (tag)
+
+    const idx = parts.findIndex(p => timestampRegex.test(p) || p === 'snapshot');
+
+    let remotePath, prefix;
+    if (idx === -1) {
+      remotePath = parts.pop() || parts.pop(); // if fs+rsync there may be a trailing slash, so this removes it. this is basename()
+      prefix = parts.join('/'); // this is dirname()
+    } else {
+      prefix = parts.slice(0, idx).join('/');
+      remotePath = parts.slice(idx).join('/');
+    }
+
+    return { prefix, remotePath };
+}
+
 // named exports
 export {
   prettyRelayProviderName,
@@ -757,7 +776,8 @@ export {
   getColor,
   prettySchedule,
   parseSchedule,
-  prettySiteLocation
+  prettySiteLocation,
+  parseFullBackupPath
 };
 
 // default export
@@ -778,5 +798,6 @@ export default {
   getColor,
   prettySchedule,
   parseSchedule,
-  prettySiteLocation
+  prettySiteLocation,
+  parseFullBackupPath
 };