#!/usr/bin/env python

# Written by Ross Cohen
# See LICENSE.TXT for license information.

try:
 import psyco
 assert psyco.__version__ >= 0x010300f0
 psyco.full()
except:
 pass

try:
    import Codeville.db
except ImportError:
    import sys, os.path
    from os.path import dirname, abspath, join
    pypath = "lib/python%d.%d/site-packages" % \
                (sys.version_info[0], sys.version_info[1])
    base   = dirname(dirname(abspath(sys.argv[0])))
    sys.path[0:0] = [ join(base, pypath) ]  # first place to look

from Codeville.db import VersionMismatchException
from Codeville.db import check_format_version, check_rebuild_version
from Codeville.db import write_rebuild_version
from Codeville.server import ServerHandler, ServerError
from Codeville.history import rebuild_from_points, rootnode
from ConfigParser import ConfigParser
from getopt import getopt, GetoptError
import os
from os import path
from random import seed
import signal
from sys import argv, exit
import sys
from time import time
from traceback import print_exc

sh = None
keyboard_interrupt = None

def signal_handler(signum, frame):
    print 'Shutting down...'
    sh.rs.doneflag.set()

def run(args):
    seed(time() + os.getpid())

    if sys.platform == 'win32':
        daemonize = False
        noconfig = True
    else:
        daemonize = True
        noconfig = False
        configfile = '/etc/cdvserver.conf'

    # parse command line arguments
    initialize = False
    rebuild    = False
    try:
        optlist, args = getopt(args, 'bc:df:il:no:p:ru:')
    except GetoptError:
        print """Valid options are:
	-b
	-c <configfile>
	-d
	-f <datadir>
	-i
	-l <logfile>
	-n
	-o <port>
	-p <pidfile>
	-r
	-u <user>"""
        return 1

    # do a first pass of the command line to pick up an alternate config
    for (opt, arg) in optlist:
        if opt == '-c':
            configfile = arg
        elif opt == '-n':
            noconfig = True

    config = ConfigParser()

    # set the defaults
    config.add_section('control')
    config.set('control',    'pidfile',    '/var/run/cdvserver.pid')
    config.set('control',    'backup',     'False')
    config.set('control',    'port',       '6601')
    if sys.platform == 'win32':
        config.set('control', 'datadir',    os.getcwd())
    else:
        config.set('control', 'datadir', '/var/lib/cdvserver')
        config.set('control', 'logfile', '/var/log/cdvserver.log')
    config.add_section('post-commit')

    # next read the config file
    if not noconfig:
        try:
            confighandle = open(configfile, 'r')
        except IOError, msg:
            print 'Could not open config file: ' + str(msg)
            return 1

        config.readfp(confighandle)
        confighandle.close()

    # finally, override everything else with command line options
    for (opt, arg) in optlist:
        if opt == '-b':
            config.set('control', 'backup', 'True')
        elif opt == '-d':
            daemonize = False
        elif opt == '-f':
            config.set('control', 'datadir', arg)
        elif opt == '-i':
            initialize = True
        elif opt == '-l':
            config.set('control', 'logfile', arg)
        elif opt == '-o':
            config.set('control', 'port', arg)
        elif opt == '-p':
            config.set('control', 'pidfile', arg)
        elif opt == '-r':
            rebuild = True
        elif opt == '-u':
            config.set('control', 'user', arg)

    if len(args) != 0:
        print 'Command takes no arguments'
        return 1

    metadata_dir = path.join(config.get('control', 'datadir'), '.cdv')

    # create the handler object
    global sh
    try:
        sh = ServerHandler(config)
    except ServerError, msg:
        print 'Error - %s' % (msg,)
        return 1

    # make sure we can read the repository format
    repo_marker = path.join(config.get('control', 'datadir'),
                            'codeville_repository')
    if initialize:
        if path.exists(repo_marker):
            print config.get('control', 'datadir') + " is already initialized as a repository"
            return 1
        crp = open(repo_marker, 'w')
        crp.close()

        sh.db_init(init=initialize)
        return 0

    else:
        if not path.exists(repo_marker):
            print config.get('control', 'datadir') + " is not a repository, start with -i to initalize one"
            return 1

        try:
            check_format_version(metadata_dir)
        except VersionMismatchException, versions:
            print "error - expected version %d does not match repository version %d, you probably need to run cdvupgrade." % versions.args
            return 1

    # sanity checks
    try:
        int(config.get('control', 'port'))
    except ValueError:
        print 'Invalid port %s' % config.get('control', 'port')
        return 1

    # bind the port before forking so that we can report errors
    try:
        sh.bind(int(config.get('control', 'port')))
    except Exception, msg:
        print 'Error - ' + str(msg)
        print 'Exiting...'
        sh.close()
        return 1

    if daemonize == True:
        try:
            loghandle = open(config.get('control', 'logfile'), 'a')
        except IOError:
            print 'Could not open log file, exiting...'
            sh.close()
            return 1

        # send all our output to the log
        sys.stdout.close()
        sys.stderr.close()
        sys.stdout = loghandle
        sys.stderr = loghandle

        # open the pid file before forking so we can report errors
        try:
            pidhandle = open(config.get('control', 'pidfile'), 'w')
        except IOError:
            print 'Could not write pid file, exiting...'
            sh.close()
            return 1

        # switch to the specified user
        if config.has_option('control', 'user'):
            import pwd
            try:
                pwe = pwd.getpwnam(config.get('control', 'user'))
            except KeyError:
                print 'No such user ' + config.get('control', 'user') + ', exiting...'
                os.remove(config.get('control', 'pidfile'))
                sh.close()
                return 1

            os.chown(config.get('control', 'pidfile'), pwe.pw_uid, pwe.pw_gid)
            os.chown(config.get('control', 'logfile'), pwe.pw_uid, pwe.pw_gid)

            try:
                os.setegid(pwe.pw_gid)
                os.seteuid(pwe.pw_uid)
            except OSError, msg:
                print 'Could not switch to user ' + pwe.pw_name + ', exiting...'
                os.remove(config.get('control', 'pidfile'))
                sh.close()
                return 1

        sh.db_init()

        pid = os.fork()
        if pid:
            pidhandle.write(str(pid))
            pidhandle.close()
            return 0

        pidhandle.close()

    else:
        sh.db_init()

    if rebuild:
        print 'Rebuilding...'

        # Don't sync the same point twice, this includes the root node
        points = sh.repolistdb.values()
        unique_points = dict.fromkeys(points)
        if unique_points.has_key(rootnode):
            del unique_points[rootnode]
        points = unique_points.keys()
        points[:0] = [rootnode]

        txn = sh.txn_begin()
        rebuild_from_points(sh, points, txn)
        sh.txn_commit(txn)
        write_rebuild_version(metadata_dir)
    else:
        try:
            check_rebuild_version(metadata_dir)
        except VersionMismatchException, versions:
            print "error - auxiliary format %d does not match repository format %d, you need to start the server with -r to rebuild" % versions.args
            return 1

    retval = 0

    print 'Listening for clients...'
    signal.signal(signal.SIGHUP, signal_handler)
    signal.signal(signal.SIGPIPE, signal.SIG_IGN)
    signal.signal(signal.SIGINT, signal_handler)
    signal.signal(signal.SIGTERM, signal_handler)
    try:
        sh.listen_forever()
    except:
        print_exc()
        retval = 1
    sh.close()

    if daemonize == True:
        if config.has_option('control', 'user'):
            os.seteuid(os.getuid())
        os.remove(config.get('control', 'pidfile'))

    return retval

if __name__ == '__main__':
    #import profile
    #retval = profile.run('run(argv[1:])')
    retval = run(argv[1:])
    exit(retval)