#!/usr/bin/env python

import os,sys,string,re
from optparse import OptionParser

pathInfo = {\
            'acml': './acml4.4.0',
            'fftw': './fftw',
            'msc':  '/msc',
           }

validShells = {\
               'bash':['.bashrc','.bash_profile'],
               'csh': ['.cshrc'],
              }

environment = [\
                { 'name': 'DAMASK_ROOT',
                  'delete':'DamaskRoot',
                  'substitute':'[DamaskRoot]',
                  'append': False,
                 },
                { 'name': 'DAMASK_BIN',
                  'delete':'os.path.join(DamaskRoot,"bin")',
                  'substitute':'[os.path.join(DamaskRoot,"bin")]',
                  'append': False,
                 },
                { 'name': 'PATH',
                  'delete':'"${DAMASK_BIN}"',
                  'substitute':'["${DAMASK_BIN}"]',
                  'append': True,
                 },
                { 'name': 'PYTHONPATH',
                  'delete':'"${DAMASK_ROOT}/lib"',
                  'substitute':'["${DAMASK_ROOT}/lib"]',
                  'append': True,
                 },
                { 'name': 'LD_LIBRARY_PATH',
                  'delete':'"acml"',                                                 # what keywords trigger item deletion from existing path 
                  'substitute':'[os.path.join(pathInfo["acml"],"ifort64_mp/lib"),\
                                 os.path.join(pathInfo["acml"],"ifort64/lib")]',     # what to substitute for deleted path items
                  'append': True,                                                    # whether new entries append to existing ${env}
                 },
              ]
parser = OptionParser(usage="%prog [options]", description = """
Sets up your shell resource to be compatible with DAMASK. 
""" + string.replace('$Id$','\n','\\n')
)

parser.add_option("-s","--shell", type="string", 
                  dest = "shell", \
                  help = "type of shell, e.g. "+', '.join(validShells.keys())+" [%default]")

parser.set_defaults(shell = 'bash')

(options, args) = parser.parse_args()

DamaskRoot = os.path.normpath(os.path.join(os.path.dirname(os.path.realpath(sys.argv[0])),'../'))
try:                                        # check for user-defined pathinfo
  file = open(os.path.join(DamaskRoot,'lib/pathinfo'))
  content = file.readlines()
  file.close()
  for line in content:
    pathInfo[line.split()[0].lower()] = os.path.normpath(line.split()[1])
except:
  pass

theShell = options.shell.lower()
theHome = os.getenv('USERPROFILE') or os.getenv('HOME')

if theShell == 'bash':
  for theRC in validShells[theShell]:
    thePath = os.path.join(theHome,theRC)
    if os.path.exists(thePath):
      rc = open(os.path.join(theHome,theRC))
      content = map(string.strip,rc.readlines())
      rc.close()

      output = []
      for var in environment: var['matched'] = False
  
      for line in content:
        for var in environment:
          m = re.search(r'^(.*? %s=)([^;]*)(.*)$'%var['name'],line)
          if m:
            substitute = [path for path in m.group(2).split(':') if eval(var['delete']) not in path] + \
                         eval(var['substitute'])
            line = m.group(1)+':'.join(substitute)+m.group(3)
            var['matched'] = True

        output.append(line)

      for var in environment:
        if not var['matched']:
          output.append('export %s=%s'%(var['name'],':'.join({True:['${%s}'%var['name']],False:[]}[var['append']]+\
                                                             eval(var['substitute']))))

      rc = open(os.path.join(theHome,theRC),'w')
      rc.write('\n'.join(output)+'\n')
      rc.close()

elif theShell == 'csh':
  print 'csh not supported yet...'