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

from optparse import OptionParser, Option

# -----------------------------
class extendableOption(Option):
# -----------------------------
# used for definition of new option parser action 'extend', which enables to take multiple option arguments
# taken from online tutorial http://docs.python.org/library/optparse.html
  
  ACTIONS = Option.ACTIONS + ("extend",)
  STORE_ACTIONS = Option.STORE_ACTIONS + ("extend",)
  TYPED_ACTIONS = Option.TYPED_ACTIONS + ("extend",)
  ALWAYS_TYPED_ACTIONS = Option.ALWAYS_TYPED_ACTIONS + ("extend",)

  def take_action(self, action, dest, opt, value, values, parser):
    if action == "extend":
      lvalue = value.split(",")
      values.ensure_value(dest, []).extend(lvalue)
    else:
      Option.take_action(self, action, dest, opt, value, values, parser)


########################################################
# MAIN
########################################################

parser = OptionParser(option_class=extendableOption, usage='%prog options', description = """
Configures the compilation and installation of DAMASK

""")
defaults={'DAMASK_BIN':'depending on access rights',
          'FFTW_ROOT':'/usr',
          'MSC_ROOT' :'/msc',
          'DAMASK_NUM_THREADS':4,
          'MARC_VERSION':'2015',
          'spectralOptions':{},
         }

#--- if local config file exists, read, otherwise assume global config file  ------------------------
configFile = os.path.join(os.getenv('HOME'),'.damask/damask.conf') \
             if os.path.isfile(os.path.join(os.getenv('HOME'),'.damask/damask.conf')) \
			 else '/etc/damask.conf'

#--- set default values according to read in values  ------------------------------------------------
try:
  with open(configFile,'r') as f:
    print('\n<<<<< reading default values from %s\n'%configFile)
    for line in f:
      line = line.strip()
      if line.startswith('#') or line == '':
        pass

      [key,value] = (re.split('[= ]',line)+[None,None])[:2]
      
      if key == 'DAMASK_NUM_THREADS':
        defaults['DAMASK_NUM_THREADS'] = int(value)
      if key == 'DAMASK_BIN':
        defaults['DAMASK_BIN'] = value
except IOError:
  pass

parser.add_option('--prefix',                dest='prefix', metavar='string',
                                             help='location of (links to) DAMASK executables [%default]')
parser.add_option('--with-OMP-threads','--with-omp-threads',      
                                             dest='threads', type='int', metavar='int',
                                             help='number of openMP threads [%default]')
parser.add_option('--with-spectral-options', dest='spectraloptions', action='extend', metavar='<string LIST>',
                                             help='options for compilation of spectral solver')

parser.set_defaults(prefix      = defaults['DAMASK_BIN'])
parser.set_defaults(mscRoot     = defaults['MSC_ROOT'])
parser.set_defaults(marcVersion = defaults['MARC_VERSION'])
parser.set_defaults(threads     = defaults['DAMASK_NUM_THREADS'])
parser.set_defaults(spectraloptions = [])

(options,filenames) = parser.parse_args()


#--- read config file if present to keep comments and order ---------------------------------------
output = []
try: 
  with open(configFile,'r') as f:
    for line in f:
      line = line.strip()
      items = re.split('[= ]',line)
    
      if (not line or items[0].startswith('#')):
        pass
      if items[0] == 'DAMASK_BIN':
        line = '%s=%s'%(items[0],options.prefix)
        options.prefix ='depending on access rights'
      if items[0] == 'MSC_ROOT':
        line = '%s=%s'%(items[0],options.mscRoot)
        options.mscRoot =''
      if items[0] == 'MARC_VERSION':
        line = '%s=%s'%(items[0],options.marcVersion)
        options.marcVersion =''
      if items[0] == 'DAMASK_NUM_THREADS':
        line = '%s=%s'%(items[0],options.threads)
        options.threads =''
      for spectralOption in options.spectraloptions:
        [key,value] = re.split('[= ]',spectralOption)[0:2]
        if key == items[0]:
          line = '%s=%s'%(items[0],value)
          options.spectraloptions.remove(spectralOption)
      output.append(line)
except IOError:
  pass

#--- write remaining options --------------------------------------------------------------------------
for opt, value in options.__dict__.items():
  if opt == 'prefix' and value != 'depending on access rights':
    output.append('DAMASK_BIN=%s'%value)
  if opt == 'mscRoot' and value != '':
    output.append('MSC_ROOT=%s'%value)
  if opt == 'marcVersion' and value != '':
    output.append('MARC_VERSION=%s'%value)
  if opt == 'threads' and value != '':
    output.append('DAMASK_NUM_THREADS=%s'%value)

for spectralOption in options.spectraloptions:
  output.append(spectralOption)

#--- decide where do save the data -------------------------------------------------------------------
configDir = '/etc' if os.access('/etc/', os.W_OK) \
                   else os.path.join(os.getenv('HOME'),'.damask')           # use system-wide config if possible
configFileNew = os.path.join(configDir,'damask.conf')

if not os.path.isdir(configDir):
  os.mkdir(configDir)

print('\n>>>>> writing values to %s\n'%configFileNew)
with open(configFileNew,'w') as f:
  for line in output:
    print(line)
    f.write(line+'\n')