import ldap
import smtplib
import os

from cryptography.hazmat.primitives import serialization as crypto_serialization
from cryptography.hazmat.primitives.asymmetric import rsa
from cryptography.hazmat.backends import default_backend as crypto_default_backend


def validate(config, validate_remote=False):
    if not os.path.exists(config["JWT"]["PUBLIC_KEY"]):
        raise Exception(f'Public key does not exist {config["JWT"]["PUBLIC_KEY"]}')

    if not os.path.exists(config["JWT"]["PRIVATE_KEY"]):
        raise Exception(f'Private key does not exist {config["JWT"]["PRIVATE_KEY"]}')

    if not validate_remote:
        return

    conn = ldap.initialize(config["LDAP"]["URI"])
    if config["LDAP"].get("TIMEOUT"):
        conn.set_option(ldap.OPT_NETWORK_TIMEOUT, config["LDAP"]["TIMEOUT"])
    conn.simple_bind_s(config["LDAP"]["BIND_DN"], config["LDAP"]["BIND_PW"])
    conn.unbind_s()

    with smtplib.SMTP(
        host=config["SMTP"]["HOST"],
        port=config["SMTP"]["PORT"],
    ) as smtp:
        if config["SMTP"].get("TLS"):
            smtp.starttls()

        if config["SMTP"].get("LOGIN"):
            smtp.login(
                user=config["SMTP"]["LOGIN"],
                password=config["SMTP"].get("PASSWORD"),
            )


def setup_dev_keypair(config):
    if os.path.exists(config["JWT"]["PUBLIC_KEY"]) or os.path.exists(
        config["JWT"]["PRIVATE_KEY"]
    ):
        return

    key = rsa.generate_private_key(
        backend=crypto_default_backend(), public_exponent=65537, key_size=2048
    )
    private_key = key.private_bytes(
        crypto_serialization.Encoding.PEM,
        crypto_serialization.PrivateFormat.PKCS8,
        crypto_serialization.NoEncryption(),
    )
    public_key = key.public_key().public_bytes(
        crypto_serialization.Encoding.OpenSSH, crypto_serialization.PublicFormat.OpenSSH
    )

    with open(config["JWT"]["PUBLIC_KEY"], "wb") as fd:
        fd.write(public_key)

    with open(config["JWT"]["PRIVATE_KEY"], "wb") as fd:
        fd.write(private_key)