import argparse
import ConfigParser
import os

import zuul.scheduler
import zuul.launcher.jenkins
import zuul.trigger.gerrit

import logging.config

def parse_arguments():
    parser = argparse.ArgumentParser(description='Project gating system.')
    parser.add_argument('-c', dest='config',
                        help='specify the config file')
    return parser.parse_args()

def read_config(args):
    config=ConfigParser.ConfigParser()
    if args.config:
        locations = [args.config]
    else:
        locations = ['/etc/zuul/zuul.conf',
                     '~/zuul.conf']
    for fp in locations:
        if os.path.exists(os.path.expanduser(fp)):
            config.read(fp)
            return config
    raise Exception("Unable to locate config file in %s" % locations)

def setup_logging(config):
    if config.has_option('zuul', 'log_config'):
        fp = os.path.expanduser(config.get('zuul', 'log_config'))
        if not os.path.exists(fp):
            raise Exception("Unable to read logging config file at %s" % fp)
        logging.config.fileConfig(fp)
    else:
        logging.basicConfig(level=logging.DEBUG)

def main(config):
    sched = zuul.scheduler.Scheduler(config)

    jenkins = zuul.launcher.jenkins.Jenkins(config, sched)
    gerrit = zuul.trigger.gerrit.Gerrit(config, sched)

    sched.setLauncher(jenkins)
    sched.setTrigger(gerrit)
    sched.run()

if __name__ == '__main__':
    args = parse_arguments()
    config = read_config(args)
    setup_logging(config)
    main(config)