import argparse
import logging
import os
import sys

from jinja2 import Environment
from jinja2 import FileSystemLoader


logging.basicConfig(stream=sys.stdout, level=logging.DEBUG)
log = logging.getLogger('mysql_template_config')

if __name__ == '__main__':
    parser = argparse.ArgumentParser()
    parser.add_argument('-c', '--config-template')
    parser.add_argument('-o', '--config-file')
    args = parser.parse_args()
    if os.getenv('MYSQL_ROLE'):
        assert os.environ['MYSQL_ROLE'] in ['replica', 'source'], 'MYSQL_ROLE must be one of [replica, source]'
    env_variables = os.environ.items()
    jinja_env = Environment(
        loader=FileSystemLoader('/'), lstrip_blocks=True, trim_blocks=True
    )
    config_template = jinja_env.get_template(args.config_template)
    config_file = config_template.render(env_variables)
    log.info('%s was successfully created' % args.config_file)
    with open(args.config_file, 'w') as f:
        f.write(config_file)