#!/usr/bin/env python
# vim:set sw=4 et:

from __future__ import absolute_import

try:
    import queue
except ImportError:
    import Queue as queue

import logging
import sys
import hashlib
import argparse
import os
import socket

import certauth.certauth

import warcprox.playback
import warcprox.dedup
import warcprox.warcwriter
import warcprox.warcprox
import warcprox.controller

def _build_arg_parser(prog=os.path.basename(sys.argv[0])):
    arg_parser = argparse.ArgumentParser(prog=prog,
            description='warcprox - WARC writing MITM HTTP/S proxy',
            formatter_class=argparse.ArgumentDefaultsHelpFormatter)
    arg_parser.add_argument('-p', '--port', dest='port', default='8000',
            help='port to listen on')
    arg_parser.add_argument('-b', '--address', dest='address',
            default='localhost', help='address to listen on')
    arg_parser.add_argument('-c', '--cacert', dest='cacert',
            default='./{0}-warcprox-ca.pem'.format(socket.gethostname()),
            help='CA certificate file; if file does not exist, it will be created')
    arg_parser.add_argument('--certs-dir', dest='certs_dir',
            default='./{0}-warcprox-ca'.format(socket.gethostname()),
            help='where to store and load generated certificates')
    arg_parser.add_argument('-d', '--dir', dest='directory',
            default='./warcs', help='where to write warcs')
    arg_parser.add_argument('-z', '--gzip', dest='gzip', action='store_true',
            help='write gzip-compressed warc records')
    arg_parser.add_argument('-n', '--prefix', dest='prefix',
            default='WARCPROX', help='WARC filename prefix')
    arg_parser.add_argument('-s', '--size', dest='size',
            default=1000*1000*1000,
            help='WARC file rollover size threshold in bytes')
    arg_parser.add_argument('--rollover-idle-time',
            dest='rollover_idle_time', default=None,
            help="WARC file rollover idle time threshold in seconds (so that Friday's last open WARC doesn't sit there all weekend waiting for more data)")
    try:
        hash_algos = hashlib.algorithms_guaranteed
    except AttributeError:
        hash_algos = hashlib.algorithms
    arg_parser.add_argument('-g', '--digest-algorithm', dest='digest_algorithm',
            default='sha1', help='digest algorithm, one of {}'.format(', '.join(hash_algos)))
    arg_parser.add_argument('--base32', dest='base32', action='store_true',
            default=False, help='write digests in Base32 instead of hex')
    arg_parser.add_argument('-j', '--dedup-db-file', dest='dedup_db_file',
            default='./warcprox-dedup.db', help='persistent deduplication database file; empty string or /dev/null disables deduplication')
    arg_parser.add_argument('-P', '--playback-port', dest='playback_port',
            default=None, help='port to listen on for instant playback')
    arg_parser.add_argument('--playback-index-db-file', dest='playback_index_db_file',
            default='./warcprox-playback-index.db',
            help='playback index database file (only used if --playback-port is specified)')
    arg_parser.add_argument('--version', action='version',
            version="warcprox {}".format(warcprox.version_str))
    arg_parser.add_argument('-v', '--verbose', dest='verbose', action='store_true')
    arg_parser.add_argument('-q', '--quiet', dest='quiet', action='store_true')
    # [--ispartof=warcinfo ispartof]
    # [--description=warcinfo description]
    # [--operator=warcinfo operator]
    # [--httpheader=warcinfo httpheader]

    return arg_parser


def main(argv=sys.argv):
    arg_parser = _build_arg_parser(prog=os.path.basename(argv[0]))
    args = arg_parser.parse_args(args=argv[1:])

    if args.verbose:
        loglevel = logging.DEBUG
    elif args.quiet:
        loglevel = logging.WARNING
    else:
        loglevel = logging.INFO

    logging.basicConfig(stream=sys.stdout, level=loglevel,
            format='%(asctime)s %(process)d %(levelname)s %(threadName)s %(name)s.%(funcName)s(%(filename)s:%(lineno)d) %(message)s')

    try:
        hashlib.new(args.digest_algorithm)
    except Exception as e:
        logging.fatal(e)
        exit(1)

    if args.dedup_db_file in (None, '', '/dev/null'):
        logging.info('deduplication disabled')
        dedup_db = None
    else:
        dedup_db = warcprox.dedup.DedupDb(args.dedup_db_file)

    recorded_url_q = queue.Queue()

    ca_name = 'Warcprox CA on {}'.format(socket.gethostname())[:64]
    ca = certauth.certauth.CertificateAuthority(args.cacert, args.certs_dir,
                                                ca_name=ca_name)

    proxy = warcprox.warcprox.WarcProxy(
            server_address=(args.address, int(args.port)), ca=ca,
            recorded_url_q=recorded_url_q,
            digest_algorithm=args.digest_algorithm)

    if args.playback_port is not None:
        playback_index_db = warcprox.playback.PlaybackIndexDb(args.playback_index_db_file)
        playback_server_address=(args.address, int(args.playback_port))
        playback_proxy = warcprox.playback.PlaybackProxy(server_address=playback_server_address,
                ca=ca, playback_index_db=playback_index_db,
                warcs_dir=args.directory)
    else:
        playback_index_db = None
        playback_proxy = None

    warc_writer = warcprox.warcwriter.WarcWriter(directory=args.directory,
            gzip=args.gzip, prefix=args.prefix, port=int(args.port),
            rollover_size=int(args.size), base32=args.base32,
            dedup_db=dedup_db, digest_algorithm=args.digest_algorithm,
            playback_index_db=playback_index_db)
    warc_writer_thread = warcprox.warcwriter.WarcWriterThread(
            recorded_url_q=recorded_url_q, warc_writer=warc_writer,
            rollover_idle_time=int(args.rollover_idle_time) if args.rollover_idle_time is not None else None)

    controller = warcprox.controller.WarcproxController(proxy, warc_writer_thread, playback_proxy)
    controller.run_until_shutdown()


if __name__ == '__main__':
    main()