import os,fnmatch
import tempfile,subprocess
from optparse import OptionParser
from collections import deque
import time

### GLOBALS
LOCAL_DIRECTORY = "/home/sdobbs/transfer_test" # set this to the base directory 
FILE_GLOB = "dana_rest_*.hddm"  # transfer files that match this
NUM_TO_TRANSFER = 3  # number of files to transfer per gridftp invocation

REMOTE_HOST = "numep-grid6.research.northwestern.edu"
REMOTE_DIRECTORY = "/mnt/xrootd/gluex/dc2/transfer_test"

LOG_FILENAME = "transfer.log"
LOG_ERROR_FILENAME = "transfer-err.log"
VERBOSE = False


if __name__ == "__main__":
    ### handle runtime options
    parser = OptionParser()
    parser.add_option("-v", "--verbose", action="store_true", dest="verbose",
                      help="print verbose output to screen")
    parser.add_option("-m", "--match", dest="glob",
                      help="transfer files that match a particular pattern (supports *,?,[])", metavar="GLOB")
    parser.add_option("-n", "--num-files", dest="num_files",
                      help="number of files to transfer at once", metavar="NUM_FILES")

    (options, args) = parser.parse_args()
    if options.verbose: VERBOSE = options.verbose
    if options.glob: FILE_GLOB = options.glob
    if options.num_files: NUM_TO_TRANSFER = options.num_file

    ### build list of files
    filelist = deque()
    for root, dirs, files in os.walk(LOCAL_DIRECTORY):
        for f in fnmatch.filter(files, FILE_GLOB):
            filelist.append( os.path.join(root,f) )

    ### open files for logging
    logfile = open(LOG_FILENAME, "a")
    logerrfile = open(LOG_ERROR_FILENAME, "a")

    ### transfer files
    done = False
    while not done:
        tf = tempfile.NamedTemporaryFile(mode='w')
        reportstr = "copying the following files:\n"

        for i in xrange(NUM_TO_TRANSFER):
            try:
                filepath = filelist.popleft()
                filename = filepath.split("/")[-1]
                #reportstr = reportstr + filepath + "\n"

                filepair = "file:///" + filepath + " gsiftp://" + REMOTE_HOST + REMOTE_DIRECTORY + "/" + filename
                reportstr = reportstr + filepair + "\n"
                print >>tf, filepair
            except IndexError:
                done = True

        # make sure that the file names are written to disk so that globus-url-copy can read them
        tf.flush()

        cmd = "globus-url-copy -f " + tf.name

        print >>logfile, reportstr
        if VERBOSE: print reportstr
        #if VERBOSE: print cmd
    
        process = subprocess.Popen(cmd.split(), shell=False, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        (cmdstdout, cmdstderr) = process.communicate()
        if process.returncode != 0:
            print "Error with transfer! (code %d)" % (process.returncode)
            print cmdstderr
            print >>logerrfile, "Error with transfer! (code %d)" % (process.returncode)
            print >>logerrfile, cmdstderr

    ### cleanup
    logfile.close()
    logerrfile.close()