#! /usr/bin/env python
# -----------------------------------------------------------------------
# Licensed to the Apache Software Foundation (ASF) under one
# or more contributor license agreements.  See the NOTICE file
# distributed with this work for additional information
# regarding copyright ownership.  The ASF licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License.  You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing,
# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied.  See the License for the
# specific language governing permissions and limitations
# under the License.
# -----------------------------------------------------------------------

# +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
# +
# + ducc_disk_info
# +
# + purpose: report on DUCC_HOME disk usage
# + 
# + input: none (DUCC_HOME implied from location of this script)
# + 
# + output: filesystem=<i>% quota=<j>%
# + 
# + exit code: the greater of { i, j }
# +
# +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

import os
import subprocess
import sys

from optparse import HelpFormatter
from optparse import OptionGroup
from optparse import OptionParser

# ----------------------------------------------

# Extend OptionParser class
class ExtendedOptionParser(OptionParser):
    # override epilog formatter so 
    # that newlines are not deleted!
    def format_epilog(self, formatter):
        return self.epilog

# ----------------------------------------------

cmd_df = 'df'
cmd_quota = 'quota'

code = -1
message = 'DUCC_HOME: '

# epilog for --help
def get_epilog():
    epilog = ''
    epilog = epilog + '\n'
    epilog = epilog+'Purpose: display the filesystem and quota usage for the DUCC_HOME directory relative to the location of this script.'
    epilog = epilog + '\n'
    return epilog

# parse command line
def parse_cmdline():
    global options
    parser = ExtendedOptionParser(epilog=get_epilog())
    width = 45
    parser.formatter.help_position = width
    parser.formatter.max_help_position = width
    parser.add_option('--code', action='store_true', dest='flag_code', default=False, 
        help='display exit code, which is the greater of disk usage percentage and quota usage percentage')
    parser.add_option('--debug', action='store_true', dest='flag_debug', default=False, 
        help='display debug information')
    parser.add_option('--nomsg', action='store_false', dest='flag_msg', default=True, 
        help='suppress display of filesystem and quota percentages used message')
    (options, args) = parser.parse_args()

# normalize path to always end with /
def normalize_path(path):
    retVal = path
    if(not path.endswith('/')):
        retVal = path+'/'
    return retVal

# normalize quota value to bytes
def normalize_quota(value):
    if(value.endswith('M')):
        tval = value.split('M')[0]
        retVal = int(tval)*1024*1024
    elif(value.endswith('k')):
        tval = value.split('k')[0]
        retVal = int(tval)*1024
    else:
        retVal = int(value)
    return retVal
        
# determine quota usage
def check_quota():
    global code
    global cmd_quota
    global message
    global filesystem
    try:
        p = subprocess.Popen([cmd_quota, '-A'], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        out, err = p.communicate()
        qfs = None
        data = None
        fs1 = normalize_path(filesystem)
        #print fs1
        for line in out.splitlines():
            tokens = line.split()
            #print tokens
            if(qfs == None):
                fs2 = normalize_path(tokens[0])
                #print fs2
                if(fs1 == fs2):
                    qfs = fs1
            elif(data == None):
                data = tokens
                break
        blocks = normalize_quota(data[0])
        limit = normalize_quota(data[2])
        qpct = int(blocks/(limit*1.0)*100)
        #print qfs, blocks, limit, qpct
        message = message+'quota='+str(qpct)+'%'+' '
    except Exception,e:
        emessage = 'Exception: '+str(e)
        emessage = emessage.strip()
        if(options.flag_debug):
            print emessage
        message = message+'quota='+'N/A'+' '
    return

# determine filesystem usage
def check_disk():
    global ducc_home
    global code
    global cmd_df
    global message
    global filesystem
    try:
        p = subprocess.Popen([cmd_df, ducc_home], stdout=subprocess.PIPE, stderr=subprocess.PIPE)
        out, err = p.communicate()
        pctused = 0
        for line in out.splitlines():
            tokens = line.split()
        filesystem = tokens[0].strip()
        pctused = tokens[4].split('%')[0]
        number = float(pctused)
        if(pctused > code):
            code = pctused
        message = message+'filesystem='+pctused+'%'+' '
    except Exception,e:
        emessage = 'Exception: '+str(e)
        emessage = emessage.strip()
        if(options.flag_debug):
            print emessage
        message = message+'filesystem='+'N/A'+' '
    return

# process
def process():
    check_disk()
    check_quota()
    return

# initialize
def initialize():
    global ducc_home
    pathname = os.path.dirname(sys.argv[0])   
    ducc_home = pathname.rsplit('/',2)[0]
    parse_cmdline()
    return

# main
def main(argv):  
    global ducc_home
    global message
    global code
    try:
        initialize()
        process()
    except Exception,e:
        message = 'Exception: '+str(e)
    message = message.strip()
    if(options.flag_msg):
        print message
    if(options.flag_code):
        sys.exit(code)
    
if __name__ == '__main__':
    main(sys.argv[1:])