decode b64 bytes for non-multipart message too

gpgmymail

@@ -77,6 +77,31 @@ def decode_email(message: email.message.Message) -> email.message.Message:
     # then find and replaces in decoded_bytes the b64 payload
     # with the decoded payload
     # lol
+
+    def decode_b64_part(
+        part: email.message.Message,
+        decoded_bytes: bytes,
+        most_recent_boundary: str = None
+    ) -> bytes:
+        if part.get("Content-Transfer-Encoding") == "base64":
+            b64_str = part.get_payload()
+            # remove the boundary as we don't want to change this
+            if most_recent_boundary:
+                b64_str = b64_str.replace(most_recent_boundary, "")
+            # sometimes we have leftover hyphens from a boundary, so strip:
+            # hyphens not in base64 so we know not to use them
+            # strip whitespace first
+            b64_str = b64_str.strip()
+            b64_str = b64_str.strip('-')
+            b64_str = b64_str.encode()  # turn into bytes-like object
+            # this will also decode the boundary so there'll be some nonsese
+            # chars at end of email but it's nbd
+            decoded_b64_str = part.get_payload(decode=True)
+            return decoded_bytes.replace(
+                b64_str,
+                decoded_b64_str
+            )
+
     quopri_decoded_message = email.message_from_bytes(decoded_bytes)
     if quopri_decoded_message.is_multipart():
         most_recent_boundary = None
@@ -85,24 +110,17 @@ def decode_email(message: email.message.Message) -> email.message.Message:
             if part.is_multipart() and part.get_boundary():
                 most_recent_boundary = part.get_boundary()
             else:
-                if part.get("Content-Transfer-Encoding") == "base64":
-                    b64_str = part.get_payload()
-                    # remove the boundary as we don't want to change this
-                    b64_str = b64_str.replace(most_recent_boundary, "")
-                    # sometimes we have leftover hyphens from a boundary, so strip:
-                    # hyphens not in base64 so we know not to use them
-                    # strip whitespace first
-                    b64_str = b64_str.strip()
-                    b64_str = b64_str.strip('-')
-                    b64_str = b64_str.encode()  # turn into bytes-like object
-                    decoded_b64_str = part.get_payload(decode=True)
-                    decoded_bytes = decoded_bytes.replace(
-                        b64_str,
-                        decoded_b64_str
-                    )
+                decoded_bytes = decode_b64_part(
+                    part,
+                    decoded_bytes,
+                    most_recent_boundary
+                )
     else:
-        # TODO
-        pass
+        decoded_bytes = decode_b64_part(
+            quopri_decoded_message,
+            decoded_bytes,
+            None
+        )
 
     decoded_bytes = decoded_bytes.replace(
         b'Content-Transfer-Encoding: base64',