#!/usr/bin/python2.6

"""
Read a feature file containing a 0 or 1 on each line, output 
all mafs whose index in maf_file corresponds to a row having a 1

usage: %prog feature_file < maf_file
"""

import psyco_full

import sys
import bx.align.maf

def __main__():

    feature_file = sys.argv[1]

    if len( sys.argv ) > 2:
        match = int( sys.argv[2] )
    else:
        match = 1
    
    feature_vector = [ int( line ) for line in file( feature_file ) ]

    maf_reader = bx.align.maf.Reader( sys.stdin )
    maf_writer = bx.align.maf.Writer( sys.stdout )

    index = 0

    for m in maf_reader:
        if feature_vector[ index ] == match: maf_writer.write( m )
        index += 1

if __name__ == "__main__": __main__()