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

VERSION='1.0'

import pyfits
from optparse import OptionParser

import numpy


parser = OptionParser()
##parser.add_option("-i","--input",dest="InputFilename",
##                  help="Input filename (required)", metavar="RAWIMAGE")
##parser.add_option("-o","--output",dest="OutputFilename",
##                  help="Output Filename (required)", metavar="FITSIMAGE")


(options, args) = parser.parse_args ()

InputFilename = args[0]
OutputFilename = InputFilename.replace('.dat','.fits')

print InputFilename, OutputFilename

#print len(options.keys())


NX = 2160
NY = 2053

# Ouverture de l'image en mode lecture binaire (windows)
try:
    f= open(InputFilename,'rb')
except IOError :
    print "Impossible d'ouvrir l'image"
    exit (1)

# Creation de l'array d'entiers non signés + byteswap
a = numpy.fromfile(file=f, dtype=numpy.uint16, count=-1)
a.byteswap(True)
f.close()

# dispatch des parties du binaire + conversion en signed int
gauche = numpy.cast[numpy.int16](a[NX*NY/2:NX*NY]-32768)
droite = numpy.cast[numpy.int16](a[:NX*NY/2]-32768)
observables = numpy.cast[numpy.int16](a[-5:-1]-32768)

# Construction de l'image (flip de la partie droite)
b=numpy.empty(NX,dtype=numpy.int16)
gauche.resize(NY,NX/2)
droite.resize(NY,NX/2)
b = numpy.hstack((gauche,numpy.fliplr(droite)))


# Creation de l'objet fits
hdu = pyfits.PrimaryHDU(b)
hdulist = pyfits.HDUList([hdu])

prihdr = hdulist[0].header

prihdr.update('BSCALE',1,'scale')
prihdr.update('BZERO',32768,'origin of the scale')


prihdr.update('OBS1',observables[0],'Observable 1')
prihdr.update('OBS2',observables[1],'Observable 2')
prihdr.update('OBS3',observables[2],'Observable 3')
prihdr.update('OBS4',observables[3],'Observable 4')
prihdr.update('Conv','pyraw2fits','Logiciel de conversion utilise')
prihdr.update('ConvVer',VERSION,'Version de raw2fits')


of = OutputFilename

hdu.writeto(of,clobber=True)