#!/usr/bin/env python

import os

from subprocess import call
from jinja2 import Template

cookie_file = "/etc/nginx/cookies.conf"

def print_to_file(content, filename):
    with open(filename, 'a') as content_file:
        content_file.write("\n".join(content.split('\\n')))

def render_nginx_config(env):
    with open('./nginx.conf', 'r') as content_file:
        content = content_file.read()
        template = Template(content)
        print_to_file(template.render(env), "/etc/nginx/nginx.conf")

def generate_dh_param():
    call(["openssl", "dhparam", "-out", "/etc/ssl/certs/dhparam.pem", "4096"])

def set_cookie_value(name, value):
    print_to_file("add_header Set-Cookie 'conjur_{0}={1}';".format(name, value), cookie_file)

def read_env():
    conjur_username = os.environ.get('CONJUR_USERNAME')
    conjur_password = os.environ.get('CONJUR_PASSWORD')

    if conjur_username:
        set_cookie_value('username', conjur_username)

    if conjur_password:
        set_cookie_value('password', conjur_password)

    conjur_appliance_url = os.environ.get('CONJUR_APPLIANCE_URL')
    conjur_appliance_ca = os.environ.get('CONJUR_APPLIANCE_CA')
    server_hostname = os.environ.get('SERVER_HOSTNAME', 'localhost')
    server_ssl_crt = os.environ.get('SERVER_SSL_CRT')
    server_ssl_key = os.environ.get('SERVER_SSL_KEY')
    dh_param = os.environ.get('DH_PARAM_PEM')

    server_ssl = False

    if server_ssl_crt and server_ssl_key:
        server_ssl = True
        print_to_file(server_ssl_key, "/etc/nginx/ssl.key")
        print_to_file(server_ssl_crt, "/etc/nginx/ssl.crt")

        if dh_param:
            print_to_file(dh_param, "/etc/ssl/certs/dhparam.pem")
        else:
            generate_dh_param()

    appliance_ca = False

    if conjur_appliance_ca:
        appliance_ca = True
        print_to_file(conjur_appliance_ca, "/etc/nginx/conjur.ca")

    env = {
        "server_ssl": server_ssl,
        "server_hostname": server_hostname,
        "appliance_ca": appliance_ca,
        "conjur_appliance_url": conjur_appliance_url
    }

    render_nginx_config(env)

read_env()

os.system('/usr/sbin/nginx -g "daemon off; error_log stderr info;"')