edc

#!/data/data/com.termux/files/usr/bin/python3
import datetime, fernet, getpass, hashlib, os, sys
class EDC():
    def __init__(self, keystr: str, file: str) -> None:
        key              = fernet.base64.urlsafe_b64encode(hashlib.sha256(keystr.encode()).digest())
        self.fernet      = fernet.Fernet(key)
        self.hash        = hashlib.sha256(hashlib.sha256(keystr.encode()).hexdigest().encode()).hexdigest()
        self.file        = file
        self.encryptData = lambda data: self.fernet.encrypt(data)
        self.decryptData = lambda data: self.fernet.decrypt(data)

    def encrypt(self) -> None:
        with open(self.file, 'r') as file:
            lines = file.readlines()
            if len(lines) != 0:
                if lines[0][0] == ':':
                    raise Exception("EncryptError: {} is already encrypted ".format(self.file))

        with open(self.file, 'rb') as file:
            data = file.read()
        data = self.encryptData(data)
        with open(self.file, 'wb') as file:
            file.write(data)

        with open(self.file, 'r') as file:
            lines = file.readlines()
        lines     = [':' + self.hash + '\n'] + lines
        with open(self.file, 'w') as file:
            file.writelines(lines)
            
    def decrypt(self) -> None:
        with open(self.file, 'r') as file:
            lines = file.readlines()
        if lines[0] != ':' + self.hash + '\n':
            print(lines[0])
            raise Exception("KeyError: Invalid key")

        dt = str(datetime.datetime.now().strftime("%Y-%m-%d_%H:%M:%S"))
        with open(self.file, 'rb') as outfile:
            with open('/data/data/com.termux/files/home/.config/edm/cache/'+dt, 'wb') as infile:
                infile.write(outfile.read())
        lines = lines[1:]
        with open(self.file, 'w') as file:
            file.writelines(lines)

        with open(self.file, 'rb') as file:
            data = file.read()
        try: 
            data = self.decryptData(data)
        except fernet.InvalidToken:
            with open(self.file, 'r') as file:
                lines = file.readlines()
            lines = [':' + self.hash + '\n' ] + lines
            with open(self.file, 'w') as file:
                file.writelines(lines)
            raise KeyboardInterrupt
        with open(self.file, 'wb') as file:
            file.write(data)

    def editor(self, estr = "vi {} {}") -> None:
        self.decrypt()
        os.system(estr.format('-n', self.file))
        self.encrypt()

    def new(self) -> None:
        open(self.file, 'a')
        self.encrypt()

def main(args):
    file = args[0]
    try:
        open(file)
    except FileNotFoundError:
        if 'y' == input("Do you want to create file: {} (y/n)".format(file)).lower():
            key1 = getpass.getpass("Key         : ")
            key2 = getpass.getpass("Re Enter Key: ")
            if key1 == key2:
                edc = EDC(key1, file)
                edc.new()
                edc.editor()
        sys.exit()

    if '-a' in args:
        try:
            action = args[args.index('-a') +1]
            if action == 'e':
                key1 = getpass.getpass("Key         : ")
                key2 = getpass.getpass("Re Enter Key: ")
                if key1 == key2:
                    edc = EDC(key1, file)
                    edc.encrypt()

            elif action == 'd':
                key = getpass.getpass("Key: ")
                edc = EDC(key, file)
                edc.decrypt()

            elif action.lower() == 'o':
                key = getpass.getpass("Key: ")
                edc = EDC(key, file)
                edc.editor()

        except IndexError:
            raise Exception("InvalidOptionError")

if __name__ == '__main__':
    try:
        main(sys.argv[1:])
    except IndexError:
        raise Exception("FileNotMentionedError")