#!/usr/bin/env python
import sys, os, string, re
import urllib

def parseOptions(argv):
    """
    Parses command-line options.
    Returns a dictionary with specified options as keys:
    -opt1             --> 'opt1' : None
    -opt2 val         --> 'opt2' : 'val'
    -opt3=val         --> 'opt3' : 'val'
    Usually called as
    options = parseOptions(sys.argv[1:])
    """
    options = {}
    argc = len(argv)
    i = 0
    while ( i < argc ):
        if argv[i][0] != '-':
            i = i + 1
            continue
        eq = string.find(argv[i], '=')
        if eq > 0 :
            opt = argv[i][:eq]
            val = argv[i][eq+1:]
            pass
        else:
            opt = argv[i]
            val = None
            if ( i+1 < argc and argv[i+1][0] != '-' ):
                i = i + 1
                val = argv[i]
                pass
            pass
        options[opt] = val
        i = i + 1
        pass
    return options

###########################################################################

def getAssignmentID(dataset, owner) :
    """Get Assignment ID from RefDB using Owner/Dataset Names) """

    urlbase = "http://cmsdoc.cern.ch/cms/production/www/cgi/SQL/DsOwnToAs.php?"
    url = urlbase + "DatasetName=" + dataset + "&OutputOwner=" + owner + "&scriptstep=1"
#    content = os.popen("wget -q -O - '" + url + "'").readlines();
    try:
        f = urllib.urlopen(url)
    except IOError:
        print '\nERROR accessing DsOwnToAs for Owner/Dataset: '+owner+'/'+dataset+'\n'

    content = f.readlines()

    assignment = ""
    for line in content:
        assignments = re.findall(r'Assignments.*<TD>(.*)', line)
        if assignments:
           assignments = assignments[0]
           if assignments.count(',') > 0:
               head = 'Assignments:'
           else:
               head = 'Assignment:';
           #print head,assignments
           #print assignments
           assignment = assignments.split(',')[0]
    return assignment

###########################################################################

if __name__ == '__main__':

    # parse command line options
    options = parseOptions(sys.argv[1:])

    # initialize variables
    owner = 'blank'
    dataset = 'blank'
    verbose = '0'
    help = '0'

    # fill variables from command line
    for opt in options.keys():
        if ( opt == '-owner' ):
            owner = options[opt]
        if ( opt == '-dataset' ):
            dataset = options[opt]
        if ( opt == '-verbose' or opt == '-v'):
            verbose = '1'
        if ( opt == '-help' or opt == '-h'):
            help = '1'

    # error output or usage output
    if ( owner == 'blank' or dataset == 'blank' or help =='1' ) :
        print 'assignment.py usage:'
        print ''
        print '-owner <owner>           :                                                                                  (requested)'
        print '-dataset <dataset>       :                                                                                  (requested)'
        print '-verbose / -v            : verbose output                                                                   (optional)'
        print '-help / -h               : this message                                                                     (optional)'
        print ''
        sys.exit(0)

    id = getAssignmentID(dataset,owner)

    print 'AssignmentId for dataset: ',dataset,' owner: ',owner,' is: ',id