fix(sign)

src/Traits/SignableData.php

@@ -12,37 +12,47 @@ trait SignableData
 {
     public function sign(SignerInterface $signer): self
     {
-        // 1. Create a clone to represent the data-to-be-signed (without existing signatures)
-        $clone = clone $this;
+        // 1. Get raw data as array
+        $data = $this->toArray();
 
-        // We explicitly set digestSignatures to null or empty for the signature calculation
-        // assuming the bank expects the "business payload" only.
-        // If the bank expects the field "digestSignatures": [] to be present in signed string,
-        // we should initialize it as empty collection.
-        // Based on common practices, we exclude it or keep it null.
-        // Let's assume we exclude it (set to null if the property is nullable).
-        $clone->digestSignatures = null;
+        // 2. Remove existing signatures if any
+        unset($data['digestSignatures']);
 
-        // 2. Serialize to JSON
-        // We use JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES to match typical API expectations
-        $jsonToSign = $clone->toJson(JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);
+        // 3. Canonicalize (RFC 8785 - simple version: sort keys, remove nulls, no spaces)
+        $canonicalData = $this->canonicalizeArray($data);
+        
+        $jsonToSign = json_encode($canonicalData, JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES);
 
-        // 3. Sign
+        // 4. Sign
         $signature = $signer->sign($jsonToSign);
 
-        // 4. Attach signature to the original object
+        // 5. Attach signature to the original object
         if ($this->digestSignatures === null) {
             $this->digestSignatures = new DataCollection(DigestSignatureData::class, []);
         }
 
-        // We can't push to DataCollection directly if it's not array-access compatible in all versions,
-        // but Spatie DataCollection is usually iterable.
-        // Safest way is to reconstruct it.
         $current = array_values($this->digestSignatures->toCollection()->all());
-        $current[] = new DigestSignatureData($signature, 'cms');
+        $current[] = new DigestSignatureData($signature, 'rsa');
 
         $this->digestSignatures = new DataCollection(DigestSignatureData::class, $current);
 
         return $this;
     }
+
+    private function canonicalizeArray(array $array): array
+    {
+        // Remove nulls and empty strings
+        $array = array_filter($array, fn($v) => $v !== null);
+
+        // Sort keys lexically
+        ksort($array);
+
+        foreach ($array as $key => $value) {
+            if (is_array($value)) {
+                $array[$key] = $this->canonicalizeArray($value);
+            }
+        }
+
+        return $array;
+    }
 }