Extract TCF core metadata decoder into VG-Core protocol layer

manifest.json

@@ -37,6 +37,7 @@
     "src/background/request-observer.js",
     "src/background/gvl-service.js",
     "src/core/binary-utils.js",
+    "src/core/tcf-core-metadata-decoder.js",
     "src/background.js"
   ]
 },

src/background.js

@@ -502,43 +502,3 @@ async function persistObservedRequest(observedRequest) {
     tx.onerror = () => reject(tx.error);
   });
 }
-
-function decodeTcStringCoreMetadata(tcString) {
-  if (!tcString || typeof tcString !== "string") {
-    return null;
-  }
-
-  const coreSegment = tcString.split(".")[0];
-
-  try {
-    const bits = base64UrlToBits(coreSegment);
-
-    return {
-      version: bitsToInt(bits, 0, 6),
-      cmpId: bitsToInt(bits, 78, 12),
-      cmpVersion: bitsToInt(bits, 90, 12),
-      consentScreen: bitsToInt(bits, 102, 6),
-      consentLanguage: bitsToString(bits, 108, 12),
-      vendorListVersion: bitsToInt(bits, 120, 12),
-      tcfPolicyVersion: bitsToInt(bits, 132, 6),
-      isServiceSpecific: bitsToBoolean(bits, 138),
-      useNonStandardStacks: bitsToBoolean(bits, 139),
-      purposeOneTreatment: bitsToBoolean(bits, 200),
-      publisherCC: bitsToString(bits, 201, 12)
-    };
-  } catch (error) {
-    console.warn("VG-Observe could not decode TC string core metadata", error);
-    return null;
-  }
-}
-
-function bitsToString(bits, start, length) {
-  let result = "";
-
-  for (let index = start; index < start + length; index += 6) {
-    const charCode = bitsToInt(bits, index, 6) + 65;
-    result += String.fromCharCode(charCode);
-  }
-
-  return result;
-}

src/core/tcf-core-metadata-decoder.js

@@ -0,0 +1,39 @@
+function decodeTcStringCoreMetadata(tcString) {
+  if (!tcString || typeof tcString !== "string") {
+    return null;
+  }
+
+  const coreSegment = tcString.split(".")[0];
+
+  try {
+    const bits = base64UrlToBits(coreSegment);
+
+    return {
+      version: bitsToInt(bits, 0, 6),
+      cmpId: bitsToInt(bits, 78, 12),
+      cmpVersion: bitsToInt(bits, 90, 12),
+      consentScreen: bitsToInt(bits, 102, 6),
+      consentLanguage: bitsToString(bits, 108, 12),
+      vendorListVersion: bitsToInt(bits, 120, 12),
+      tcfPolicyVersion: bitsToInt(bits, 132, 6),
+      isServiceSpecific: bitsToBoolean(bits, 138),
+      useNonStandardStacks: bitsToBoolean(bits, 139),
+      purposeOneTreatment: bitsToBoolean(bits, 200),
+      publisherCC: bitsToString(bits, 201, 12)
+    };
+  } catch (error) {
+    console.warn("VG-Observe could not decode TC string core metadata", error);
+    return null;
+  }
+}
+
+function bitsToString(bits, start, length) {
+  let result = "";
+
+  for (let index = start; index < start + length; index += 6) {
+    const charCode = bitsToInt(bits, index, 6) + 65;
+    result += String.fromCharCode(charCode);
+  }
+
+  return result;
+}