Add Compoships for multile key relationships, first implemented with Service::class

app/Models/Scopes/SiteScope.php

@@ -17,7 +17,12 @@ class SiteScope implements Scope
 	 */
 	public function apply(Builder $builder, Model $model)
 	{
-		// @todo Need to only do this, if the original query doesnt already have a where condition with a site_id
-		$builder->where($model->getTable().'.site_id',config('site')->site_id);
+		$builder->when(
+			! collect($builder->getQuery()->wheres)->pluck('column')->contains(function($item) { return preg_match('/^(.*[^.]\.)?site_id/',$item); }),
+			function($q) use ($model)
+			{
+				return $q->where($model->getTable().'.site_id',config('site')->site_id);
+			}
+		);
 	}
 }