#!/usr/bin/env python
# -*- coding: utf-8 -*

""" bg_utils.py: general utilities for Bethe-Goldstone correlation calculation."""

from os import listdir, unlink
from os.path import join, isfile
from subprocess import call
from math import factorial

from bg_time import timer_phase
from bg_print import print_ref_header, print_ref_end

__author__ = 'Dr. Janus Juul Eriksen, JGU Mainz'
__copyright__ = 'Copyright 2017'
__credits__ = ['Prof. Juergen Gauss', 'Dr. Filippo Lipparini']
__license__ = '???'
__version__ = '0.4'
__maintainer__ = 'Dr. Janus Juul Eriksen'
__email__ = 'jeriksen@uni-mainz.de'
__status__ = 'Development'

def run_calc_hf(molecule):
   #
   molecule['input_hf'](molecule)
   #
   call(molecule['backend_prog_exe']+' &> OUTPUT.OUT',shell=True) 
   #
   molecule['get_dim'](molecule)
   #
   if (not molecule['error'][-1]): rm_dir_content(molecule)
   #
   return molecule

def run_calc_corr(molecule,drop_string,level):
   #
   molecule['input_corr'](molecule,drop_string,level)
   #
   call(molecule['backend_prog_exe']+' &> OUTPUT.OUT',shell=True)
   #
   molecule['write_energy'](molecule,level)
   #
   if (not molecule['error'][-1]): rm_dir_content(molecule)
   #
   return molecule

def rm_dir_content(molecule):
   #
   for the_file in listdir(molecule['scr']):
      #
      file_path = join(molecule['scr'],the_file)
      #
      try:
         #
         if isfile(file_path):
            #
            unlink(file_path)
      #
      except Exception as e:
         #
         print(e)
   #
   return

def ref_calc(molecule):
   #
   print_ref_header()
   #
   timer_phase(molecule,'time_tot',1,'REF')
   #
   run_calc_corr(molecule,'','REF')
   #
   timer_phase(molecule,'time_tot',1,'REF')
   #
   print_ref_end(molecule)
   #
   return molecule

def orb_string(molecule,l_limit,u_limit,tup,string):
   #
   # generate list with all occ/virt orbitals
   #
   dim = range(l_limit+1,(l_limit+u_limit)+1)
   #
   # generate list with all orbs the should be dropped (not part of the current tuple)
   #
   drop = sorted(list(set(dim)-set(tup.tolist())))
   #
   # for virt scheme, explicitly drop the core orbitals for frozen core
   #
   if ((molecule['exp'] == 'virt') and molecule['frozen']):
      #
      for i in range(molecule['ncore'],0,-1):
         #
         drop.insert(0,i)
   #
   # now write the string
   #
   inc = 0
   #
   string['drop'] = ''
   #
   for i in range(0,len(drop)):
      #
      if (inc == 0):
         #
         string['drop'] += 'DROP_MO='+str(drop[i])
      #
      else:
         #
         if (drop[i] == (drop[i-1]+1)):
            #
            if (i < (len(drop)-1)):
               #
               if (drop[i] != (drop[i+1]-1)):
                  #
                  string['drop'] += '>'+str(drop[i])
            #
            else:
               #
               string['drop'] += '>'+str(drop[i])
         #
         else:
            #
            string['drop'] += '-'+str(drop[i])
      #
      inc += 1
   #
   if (string['drop'] != ''):
      #
      string['drop'] += '\n'
   #
   return string

def n_theo_tuples(dim,k,theo_work):
   #
   theo_work.append(factorial(dim)/(factorial(k)*factorial(dim-k)))
   #
   return theo_work