#!/usr/bin/python

import sys, os, getopt

def usage():
    print ''
    print 'compare_two_list_of_dcache_files'
    print ''
    print 'compares a file with dcache url\'s (base_file) to file with filenames (comparison_file)'
    print 'writes out new file with dcache url\'s which are not in both files (output_file)'
    print ''
    print 'required parameters:'
    print '--tier (-t)                 <tier>     :       hit, digi, dst to use the default file names'
    print ''
    print 'optional parameters:'
    print '--help (-h)                            :       help'
    print '--debug (-d)                           :       debug statements'
    print ''
    print '--base_file_name (-b)       <file_name>:       base_file with dcache url\'s, default: <tier>_catalog.cpy'
    print '--comparison_file_name (-c) <file_name>:       comparison_file with file_names, default: <tier>_resilient.cpy'
    print '--output_file_name (-o)     <file_name>:       output_file with dcache url\'s not in both files, default: <tier>_to_be_staged.cpy'
    print ''
    

def main(argv) :

    # default
    tier = ''
    base_file_name = ''
    comparison_file_name = ''
    output_file_name = ''

    try:
        opts, args = getopt.getopt(argv, "hdt:b:c:o:", ["help", "debug", "tier=", "base_file_name=", "comparison_file_name=", "output_file_name="])
    except getopt.GetoptError:
        usage()
        sys.exit(2)

    # check command line parameter
    for opt, arg in opts :
        if opt in ("-h","--help") :
            usage()
            sys.exit()
        elif opt in ("-d","--debug") :
            global _debug
            _debug = 1
        elif opt in ("-t","--tier") :
            tier = arg
        elif opt in ("-b","--base_file_name") :
            base_file_name = arg
        elif opt in ("-c","--comparison_file_name") :
            comparison_file_name = arg
        elif opt in ("-o","--output_file_name") :
            output_file_name = arg

    if base_file_name == '':
        if tier == '' :
            usage()
            sys.exit()
        else :
            base_file_name = tier+'_catalog.cpy'

    if comparison_file_name == '':
        if tier == '' :
            usage()
            sys.exit()
        else :
            comparison_file_name = tier+'_resilient.cpy'

    if output_file_name == '':
        if tier == '' :
            usage()
            sys.exit()
        else :
            output_file_name = tier+'_to_be_staged.cpy'

    ## read in base file
    base_files = []
    try:
        base = open(base_file_name)
    except IOError:
        print 'Could not open file: ',base_file_name
        sys.exit()
        
    base_line = base.readline()
    counter = 0

    while base_line :
        base_line = base_line.strip()
        base_files.append(base_line)
        counter += 1
        base_line = base.readline()

    print 'Read in ',counter,' files from ',base_file_name

    # read in comparison file
    comparison_files = []
    try:
        comparison = open(comparison_file_name)
    except IOError:
        print 'Could not open file: ',comparison_file_name
        sys.exit()
        
    comparison_line = comparison.readline()
    counter = 0

    while comparison_line :
        comparison_line = comparison_line.strip()
        comparison_files.append(comparison_line)
        counter += 1
        comparison_line = comparison.readline()

    print 'Read in ',counter,' files from ',comparison_file_name

    # strip base list of path
    base_stripped_files = []
    for base_file in base_files :
        base_stripped_files.append(os.path.split(base_file)[1])

    # output file of url's which still have to be staged
    output = open(output_file_name,'w')

    # check both lists for same entries
    counter_only_in_base = 0
    counter_in_both = 0
    for base_stripped_file in base_stripped_files:
        if base_stripped_file in comparison_files :
            index = base_stripped_files.index(base_stripped_file)
            counter_in_both += 1
        else :
            index = base_stripped_files.index(base_stripped_file)
            output.write(base_files[index])
            output.write('\n')
            counter_only_in_base += 1

    print 'In both files: ',counter_in_both
    print 'Only in base file ',counter_only_in_base


if __name__ == '__main__' :
    main(sys.argv[1:])