#!/usr/bin/python

# Export keywords of all fits files in the current directory to a csv file 

import os
import sys
import fnmatch
import pyfits
import string
import csv

if len(sys.argv) != 2:
  print " "
  print "Usage: fits_list_head_to_csv.py dirname "
  print " "
  sys.exit("Export keywords of all fits files in the current directory to a csv file \n")
  
toplevel = sys.argv[-1]
outfile = 'index_' + toplevel + '.csv'
outfp = open(outfile, 'w')
writer = csv.writer(outfp)
writer.writerow( ('File Name', 'Directory', 'Target', 'Observation Date', 'Exposure Time', 'Filter', 'Telescope', 'Instrument', 'Created Date') )

pattern = '*.fits'

for dirname, dirnames, filenames in os.walk(toplevel):
  for filename in fnmatch.filter(filenames, pattern):
    fullfilename = os.path.join(dirname, filename)
    
    try:    
    
      # Open a fits image file
      hdulist = pyfits.open(fullfilename)
      
    except IOError: 
      print 'Error opening ', fullfilename
      break       
    
    # Get the primary image header
    prihdr = hdulist[0]
    
    #Parse  primary header elements for the index
    if 'EXPTIME' in prihdr.header:
      imexptime = prihdr.header['EXPTIME']
    else:
      imexptime =  '  ' 
        
    if 'DATE-OBS' in prihdr.header:
      imdateobs = prihdr.header['DATE-OBS']
    else:
      imdateobs = '  '
      
    if 'TARGET'  in prihdr.header:
      imtarget = prihdr.header['TARGET']
    else:
      imtarget = '  '
      
    if 'FILTER' in prihdr.header:
      imfilter = prihdr.header['FILTER']
    else:
      imfilter = '  '
      
    if 'TELESCOP' in prihdr.header:
      imtelescope = prihdr.header['TELESCOP']
    else:
      imtelescope = '  '
      
    if 'INSTRUME' in prihdr.header:
      iminstrument = prihdr.header['INSTRUME']
    else:
      iminstrument = '  '
      
    if 'DATE' in prihdr.header:
      imcreatedate = prihdr.header['DATE']
    else:
      imcreatedate = '  ' 
                      
    writer.writerow( (filename, dirname, imtarget, imdateobs, imexptime, imfilter, imtelescope, iminstrument, imcreatedate) )
    
outfp.close()



exit()