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

import argparse
import os
import sys
import logging
import brozzler
import threading
import time
import signal
import pprint
import traceback
import brozzler.worker

arg_parser = argparse.ArgumentParser(prog=os.path.basename(__file__),
        description='crawl-url - browse urls, follow links',
        formatter_class=argparse.ArgumentDefaultsHelpFormatter)
arg_parser.add_argument('-u', '--url', dest='amqp_url', default='amqp://guest:guest@localhost:5672/%2f',
        help='URL identifying the amqp server to talk to')
arg_parser.add_argument('-e', '--executable', dest='chrome_exe', default='chromium-browser',
        help='executable to use to invoke chrome')
arg_parser.add_argument('-n', '--max-browsers', dest='max_browsers', default='1',
        help='max number of chrome instances simultaneously browsing pages')
arg_parser.add_argument('-v', '--verbose', dest='log_level',
        action="store_const", default=logging.INFO, const=logging.DEBUG)
arg_parser.add_argument('--version', action='version',
        version="brozzler {} - {}".format(brozzler.version, os.path.basename(__file__)))
args = arg_parser.parse_args(args=sys.argv[1:])

logging.basicConfig(stream=sys.stdout, level=args.log_level,
        format='%(asctime)s %(process)d %(levelname)s %(threadName)s %(name)s.%(funcName)s(%(filename)s:%(lineno)d) %(message)s')
# the way we're using it, amqp is too verbose at debug level
logging.getLogger("amqp").setLevel(logging.INFO)

def sigterm(signum, frame):
    raise brozzler.ShutdownRequested('shutdown requested (caught SIGTERM)')
def sigint(signum, frame):
    raise brozzler.ShutdownRequested('shutdown requested (caught SIGINT)')

def dump_state(signum, frame):
    pp = pprint.PrettyPrinter(indent=4)
    state_strs = []

    for th in threading.enumerate():
        state_strs.append(str(th))
        stack = traceback.format_stack(sys._current_frames()[th.ident])
        state_strs.append("".join(stack))

    logging.warn("dumping state (caught signal {})\n{}".format(signum, "\n".join(state_strs)))

signal.signal(signal.SIGQUIT, dump_state)
signal.signal(signal.SIGTERM, sigterm)
signal.signal(signal.SIGINT, sigint)

worker = brozzler.worker.BrozzlerWorker(amqp_url=args.amqp_url,
        max_browsers=int(args.max_browsers), chrome_exe=args.chrome_exe)

worker.start()

try:
    while True:
        time.sleep(0.5)
except brozzler.ShutdownRequested as e:
    worker.shutdown_now()

    for th in threading.enumerate():
        if th != threading.current_thread():
            th.join()

logging.info("all done, exiting")