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

# Example python script for extracting lightcurve data from WTS binary fits files
# This topic was discussed at the RoPACS meeting in Munich, 2010.
# Gabor Kovacs <gkovacs@ast.cam.ac.uk>

# Please note that objects are indexed from zero in fits files
# numbering goes from 1 however when referring to candidates on the WTS webpage, etc.

try:    
    import numpy as np
    import pyfits as pf
    from optparse import OptionParser
    import sys
except ImportError:
    print "This program requires Python 2.6 or higher and pyfits,numpy packages installed."
    sys.exit(1)

def parseopts():
    usage = "usage: %prog [options] input.fits"
    parser = OptionParser(usage=usage)
    parser.add_option("-o",
                type="string", dest="outfile",  default=None, 
                help="Output file name (default: stdout)")
    parser.add_option("-e",
                type="int", dest="ext", default=1, 
                help="Extension number: 1,2,3 or 4 (default:1)")
    parser.add_option("-j",
                type="int", dest="object",  default=0, 
                help="Object index (default: 0)")           
    (option, args) = parser.parse_args()
    try:
        infile=args[0]
    except IndexError:
        parser.print_help()
        sys.exit(1)
    return (option, args)

# === main

option, args = parseopts()
    
hdu=pf.open(args[0])

tbd=hdu[option.ext].data
iobj = option.object
# === Dropping lines with NaN values.
hjds=tbd[iobj]['hjd']
filter=np.isfinite(hjds)
fluxs=tbd[iobj]['flux']
filter=np.logical_and(filter, np.isfinite(fluxs))
fluxerrs=tbd[iobj]['fluxerr']
filter=np.logical_and(filter, np.isfinite(fluxerrs))
lcascii=np.column_stack( (hjds, fluxs, fluxerrs) )
norig=len(lcascii)
lcascii=lcascii[filter] # Keeping only rows where all 3 columns are finite
print >>sys.stderr,"Object index %d: %d rows dropped %d rows remain" % (iobj, norig - len(lcascii), len(lcascii))
#Occfit takes 80 characters per line maximum!
if option.outfile is None:
    f=sys.stdout
else:
    f=option.outfile
np.savetxt(f, lcascii, fmt="%.8f")