#!/usr/bin/env python3
############################################################
# Program is part of MintPy                                #
# Copyright (c) 2013, Zhang Yunjun, Heresh Fattahi         #
# Author: Zhang Yunjun, 2-17                               #
############################################################


import sys
import numpy as np
from mintpy.utils import readfile, writefile, utils as ut


USAGE = """
usage:  range_distance.py  file  [outfile]

Generates range distance (in Radar Coordinate) for each pixel
  with required attributes read from the h5 file

input arguments:
  file    : string, input  file name/path
  outfile : string, output file name/path for 2D incidence angle 
            calculated from file in radar coord

example:
  range_distance.py  velocity.h5
  range_distance.py  timeseries.h5
"""

def usage():
    print(USAGE)
    return


def main(argv):
    try:
        File = argv[0]
        atr = readfile.read_attribute(File)
    except:
        usage()
        sys.exit(1)

    try:
        outFile = argv[1]
    except:
        outFile = 'rangeDistance.h5'

    # Calculate look angle
    range_dis = ut.range_distance(atr, dimension=2)

    # Geo coord
    if 'Y_FIRST' in atr.keys():
        print('Input file is geocoded, only center range distance is calculated: ')
        print(range_dis)
        length = int(atr['LENGTH'])
        width = int(atr['WIDTH'])
        range_dis_mat = np.zeros((length, width), np.float32)
        range_dis_mat[:] = range_dis
        range_dis = range_dis_mat

    print('writing >>> '+outFile)
    atr['FILE_TYPE'] = 'mask'
    atr['UNIT'] = 'm'
    try:
        atr.pop('REF_DATE')
    except:
        pass
    writefile.write(range_dis, out_file=outFile, metadata=atr)
    return outFile


############################################################
if __name__ == '__main__':
    main(sys.argv[1:])