#!/usr/bin/python

import sys, os, getopt

def usage():
    print ''
    print 'break_into_pieces'
    print ''
    print 'takes file with operations (base_file) and breaks them into several files with'
    print 'a specified number of operations per file (operations_per_file).'
    print 'The name of the base_file is used for hte output files with an index number added for distinction.' 
    print 'Each operation can spread over multiple lines (number_of_lines_per_operation).'
    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>_to_be_staged_srmcp.cpy'
    print '--operations_per_file (-f)  <number>   :       number of operations per file, default: 30'
    print '--lines_per_operation (-l)  <number>   :       number of lines per operation, default: 1'
    print ''
    print '--base_is_executable (-e)              :       base_file is a script and should be broken into scripts'
    print ''
    print '--srmcp (-s)                           :       srmcp mode, write main script which calls breaked files as -copyjobfile for srmcp'
    print '--srmcp_file_name (-n)      <file_name>:       file_name of srmcp main script, default: <tier>_stage_script.sh'
    print ''
    

def main(argv) :

    # default
    tier = ''
    base_file_name = ''
    operations_per_file = 30
    lines_per_operation = 1
    srmcp = 0
    srmcp_file_name = ''
    base_is_executable = 0

    try:
        opts, args = getopt.getopt(argv, "hdt:b:f:l:sn:e", ["help", "debug", "tier=", "base_file_name=", "operations_per_file=", "lines_per_operation=", "srmcp", "srmcp_file_name=", "base_is_executable"])
    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 ("-f","--operations_per_file") :
            operations_per_file = int(arg)
        elif opt in ("-l","--lines_per_operation") :
            lines_per_operation = int(arg)
        elif opt in ("-s","--srmcp") :
            srmcp = 1
        elif opt in ("-n","--srmcp_file_name") :
            srmcp_file_name = arg
        elif opt in ("-e","--base_is_executable") :
            base_is_executable = 1

    if base_is_executable == 1 and srmcp == 1:
        print ''
        print 'Please either activate srmcp mode or switch on base_is_executable'
        usage()
        sys.exit(2)

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

    if srmcp == 1 :
        if srmcp_file_name == '' :
            if tier == '' :
                usage()
                sys.exit()
            else :
                srmcp_file_name = tier+'_stage_script.sh'
            

    try:
        base_file = open(base_file_name)
    except IOError:
        print 'Could not open file: ',base_file_name
        sys.exit()

    if srmcp == 1 :
        srmcp_file = open(srmcp_file_name,'w')
        srmcp_file.write('#!/bin/sh\n')

    base_file_name_template = os.path.splitext(base_file_name)[0]

    counter = 0
    breaker_counter = 0

    base_file_line = base_file.readline()

    if base_is_executable :
        if base_file_line[0] == '#' :
            base_file_line = base_file.readline()

    while base_file_line :

        if breaker_counter == 0 :

            base_file_break_name = base_file_name_template + '_' + str(counter)
            if  base_is_executable :
                base_file_break_name += '.sh'
            else :
                base_file_break_name += '.cpy'
            report_file_break_name = base_file_name_template + '_' + str(counter) + '.rpt'
            file = open(base_file_break_name,'w')
            if base_is_executable :
                file.write('#!/bin/sh\n')
            counter += 1
            breaker_counter = 0

        elif breaker_counter == operations_per_file :

            file.close()
            if base_is_executable :
                os.chmod(base_file_break_name,0755)

            if srmcp == 1 :
                srmcp_file.write('~/srmclient/bin/srmcp -debug=true -copyjobfile='+base_file_break_name+' -report='+report_file_break_name+'\n')
            
            base_file_break_name = base_file_name_template + '_' + str(counter)
            if  base_is_executable :
                base_file_break_name += '.sh'
            else :
                base_file_break_name += '.cpy'
            report_file_break_name = base_file_name_template + '_' + str(counter) + '.rpt'
            file = open(base_file_break_name,'w')
            if base_is_executable :
                file.write('#!/bin/sh\n')
            counter += 1
            breaker_counter = 0

        for i in range(lines_per_operation) :
            file.write(base_file_line)
            base_file_line = base_file.readline()

        breaker_counter += 1

    if srmcp == 1 :
        if os.path.exists(base_file_break_name) :
            file.close()
            if base_is_executable :
                os.chmod(base_file_break_name,0755)
            srmcp_file.write('~/srmclient/bin/srmcp -debug=true -copyjobfile='+base_file_break_name+' -report='+report_file_break_name+'\n')
        os.chmod(srmcp_file_name,0755)

    print 'File: ',base_file_name,' broken up into: ',counter,' files.'


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