fix(gtm): extend gtm config to set default consent mode on init

docs/content/scripts/tracking/google-tag-manager.md

@@ -48,6 +48,26 @@ export default defineNuxtConfig({
 })
 ```
 
+```ts [Default consent mode]
+export default defineNuxtConfig({
+  scripts: {
+    registry: {
+      googleTagManager: {
+        id: '<YOUR_ID>',
+        defaultConsent: {
+          // This can be any string or number value according to GTM documentation
+          // Here we set all consent types to 'denied' by default
+          'ad_user_data': 'denied',
+          'ad_personalization': 'denied',
+          'ad_storage': 'denied',
+          'analytics_storage': 'denied',
+        }
+      }
+    }
+  }
+})
+```
+
 ```ts [Environment Variables]
 export default defineNuxtConfig({
   scripts: {
@@ -154,6 +174,9 @@ export const GoogleTagManagerOptions = object({
 
     /** Referrer policy for analytics requests */
     authReferrerPolicy: optional(string()),
+
+    /** Default consent settings for GTM */
+    defaultConsent: optional(record(string(), union([string(), number()]))),
   })
 ```
 

src/runtime/registry/google-tag-manager.ts

@@ -2,7 +2,7 @@ import { withQuery } from 'ufo'
 import type { GTag } from './google-analytics'
 import { useRegistryScript } from '#nuxt-scripts/utils'
 import type { NuxtUseScriptOptions, RegistryScriptInput, UseFunctionType, UseScriptContext } from '#nuxt-scripts/types'
-import { object, string, optional, boolean, union, literal } from '#nuxt-scripts-validator'
+import { object, string, optional, boolean, union, literal, record, number } from '#nuxt-scripts-validator'
 
 /**
  * Improved DataLayer type that better reflects GTM's capabilities
@@ -16,7 +16,7 @@ export type DataLayer = Array<DataLayerItem>
  */
 export interface DataLayerPush {
   (...args: Parameters<GTag>): void
-  (obj: Record<string, unknown>): void
+  (obj: Record<string, unknown> | any[]): void
 }
 
 /**
@@ -109,6 +109,9 @@ export const GoogleTagManagerOptions = object({
 
   /** Referrer policy for analytics requests */
   authReferrerPolicy: optional(string()),
+
+  /** Default consent settings for GTM */
+  defaultConsent: optional(record(string(), union([string(), number()]))),
 })
 
 export type GoogleTagManagerInput = RegistryScriptInput<typeof GoogleTagManagerOptions>
@@ -161,17 +164,22 @@ export function useScriptGoogleTagManager<T extends GoogleTagManagerApi>(
               (window as any)[dataLayerName] = (window as any)[dataLayerName] || []
 
               // Create gtag function
-              function gtag() {
+              function gtag(...args: any[]) {
                 // Pushing arguments to dataLayer is necessary for GTM to process events
-                // eslint-disable-next-line prefer-rest-params
-                (window as any)[dataLayerName].push(arguments)
+                (window as any)[dataLayerName].push(args)
               }
 
               // Assign gtag to window for global access
               (window as any).gtag = gtag
 
               // Allow custom initialization
-              options?.onBeforeGtmStart?.(gtag);
+              options?.onBeforeGtmStart?.(gtag)
+
+              if (opts.defaultConsent) {
+                // Set default consent state if provided
+                // ts-disable-next-line
+                gtag('consent', 'default', opts.defaultConsent)
+              }
 
               // Push the standard GTM initialization event
               (window as any)[dataLayerName].push({