#!/usr/bin/env python

"""
    Syslog -> Irk
"""

__version__ = '0.0'

import pvl.args
import pvl.syslog.args
import pvl.syslog.rule
import pvl.irker

import logging, optparse

log = logging.getLogger('main')

def parse_options (argv) :
    """
        Parse command-line arguments.
    """

    prog = argv[0]

    parser = optparse.OptionParser(
            prog        = prog,
            usage       = '%prog: [options]',
            version     = __version__,

            # module docstring
            description = __doc__,
    )
    
    # options
    parser.add_option_group(pvl.args.parser(parser))

    # input
    parser.add_option_group(pvl.syslog.args.parser(parser))
    parser.add_option_group(pvl.syslog.rule.parser(parser))
    parser.add_option_group(pvl.irker.parser(parser))

    # parse
    options, args = parser.parse_args(argv[1:])
    
    # apply
    pvl.args.apply(options, prog)

    return options, args

def main (argv) :
    options, args = parse_options(argv)

    if args :
        # XXX: targets
        target, = args
    else :
        target = None
    
    log.info("Open syslog...")
    syslog = pvl.syslog.args.apply(options)
    
    log.info("Load rules...")
    rules = pvl.syslog.rule.apply(options)

    log.info("Connect IRK..")
    irk, target = pvl.irker.apply(options, target=target)

  
    log.info("Process syslog messages...")
    for item in syslog :
        if rules :
            match = rules.apply(item)
        else :
            match = None, item['msg']

        if not match :
            continue

        tag, line = match
        
        log.info("%s", line)

        # TODO: map tag -> target?
        if target :
            target(line)
        else :
            print tag, line
    
    # done
    log.info("Exiting...")
    return 0

if __name__ == '__main__':
    import sys

    sys.exit(main(sys.argv))