Added VC.checkRewrite() class method

Change-Id: If8a557a37a59eb850f936bcfd1a591b789f3a933
diff --git a/dev/js/src/init.js b/dev/js/src/init.js
index 16a58ff..81ed093 100644
--- a/dev/js/src/init.js
+++ b/dev/js/src/init.js
@@ -330,10 +330,16 @@
           show['collection'] = true;
         };
       };
+
       vcname.onclick = vcclick;
       if (show['collection']) {
         vcclick.apply();
       };
+
+      // Check
+      if (_checkVCrewrite(vcClass)) {
+        console.log("Rewrite!");
+      };
     };
 
     
@@ -417,3 +423,10 @@
   };
   return vc;
 };
+
+function _checkVCrewrite (vcClass) {
+  if (KorAP.koralQuery !== undefined && KorAP.koralQuery["collection"]) {
+    return vcClass.checkRewrite(KorAP.koralQuery["collection"]);
+  };
+  return false;
+}
diff --git a/dev/js/src/vc.js b/dev/js/src/vc.js
index 3e9f16e..5ba68d1 100644
--- a/dev/js/src/vc.js
+++ b/dev/js/src/vc.js
@@ -176,13 +176,39 @@
     },
 
 
+    // Check if the virtual corpus contains a rewrite
+    // This is a class method
+    checkRewrite : function (json) {
+
+      // There is a rewrite attribute
+      if (json['rewrites'] !== undefined) {
+        return true;
+      }
+
+      // There is a group to check for rewrites
+      else if (json['@type'] === 'koral:docGroup') {
+        var ops = json['operands'];
+        if (ops === undefined)
+          return false;
+
+        for (var i in ops) {
+
+          // "this" is the class
+          if (this.checkRewrite(ops[i])) {
+            return true;
+          };
+        };
+      };
+      return false;
+    },
+
     /**
      * Clean the virtual document to uspecified doc.
      */
     clean : function () {
       if (this._root.ldType() !== "non") {
-	this._root.destroy();
-	this.root(unspecDocClass.create(this));
+	      this._root.destroy();
+	      this.root(unspecDocClass.create(this));
       };
       return this;
     },