import os
from django.conf import settings
import tempfile
import subprocess
import shlex
import base64


class KKBSign(object):
    """docstring for KBBSign"""

    def check(self, rawsign, data):
        tempSignature = tempfile.NamedTemporaryFile(mode="wb", delete=False)
        tempData = tempfile.NamedTemporaryFile(mode="wb", delete=False)
        tempPubKey = tempfile.NamedTemporaryFile(mode="wb", delete=False)
        rawsign = base64.b64decode(rawsign)[::-1]
        try:
            tempSignature.write(bytes(rawsign, 'UTF-8'))
        except Exception as e:
            tempSignature.write(rawsign)
        tempSignature.seek(0)

        try:
            tempData.write(bytes(data, 'UTF-8'))
        except Exception as e:
            tempData.write(data)
        tempData.seek(0)

        cmd = "".join(["openssl x509 -pubkey -noout -in ", settings.PUBLIC_KEY_FN])
        pubkey = \
            subprocess.Popen(shlex.split(cmd), shell=False, stdin=subprocess.PIPE,
                             stdout=subprocess.PIPE).communicate()[0]
        try:
            tempPubKey.write(bytes(pubkey, 'UTF-8'))
        except Exception as e:
            tempPubKey.write(pubkey)

        tempPubKey.seek(0)

        cmd = "".join(
                ["openssl dgst -sha1 -verify ", tempPubKey.name, " -signature ", tempSignature.name, " ",
                 tempData.name])
        result = \
            subprocess.Popen(shlex.split(cmd), shell=False, stdin=subprocess.PIPE,
                             stdout=subprocess.PIPE).communicate()[0]

        tempPubKey.close()
        tempData.close()
        tempSignature.close()
        os.unlink(tempPubKey.name)
        os.unlink(tempData.name)
        os.unlink(tempSignature.name)
        return result.decode('utf-8')

    def sign64(self, text):
        tempData = tempfile.NamedTemporaryFile(delete=False)
        try:
            tempData.write(bytes(text, 'UTF-8'))
        except Exception as e:
            tempData.write(text)
        tempData.seek(0)

        tempSignature = tempfile.NamedTemporaryFile(mode="rb", delete=False)
        cmd = "".join(["openssl dgst -sha1 -sign ", settings.PRIVATE_KEY_FN, " -passin ",
                       "".join(['pass:', settings.PRIVATE_KEY_PASS]), " -out ", tempSignature.name, " ", tempData.name])
        p = subprocess.Popen(shlex.split(cmd), shell=False, stdin=subprocess.PIPE)
        p.communicate()
        signature = tempSignature.read()[::-1]
        tempData.close()
        tempSignature.close()
        os.unlink(tempData.name)
        os.unlink(tempSignature.name)
        return base64.b64encode(signature)