#!/usr/bin/env python3
############################################################
# Program is part of MintPy                                #
# Copyright(c) 2013-2019, Zhang Yunjun, Heresh Fattahi     #
# Author:  Zhang Yunjun, Heresh Fattahi                    #
############################################################


import os
import argparse
from mintpy.utils import readfile, utils as ut


# key configuration parameter name
configKeys = ['mintpy.deramp',
              'mintpy.deramp.maskFile',
             ]


###########################################################################################
TEMPLATE = """template:
## remove phase ramp for each epoch, useful to check localized deformation, i.e. volcanic, land subsidence, etc.
## [linear, quadratic]
mintpy.deramp          = auto  #[no / linear / quadratic], auto for no - no ramp will be removed
mintpy.deramp.maskFile = auto  #[filename / no], auto for maskTempCoh.h5, mask file for ramp estimation
"""

EXAMPLE = """example:
  remove_ramp.py  timeseries.h5      -m maskTempCoh.h5
  remove_ramp.py  ifgramStack.h5     -m maskTempCoh.h5  -d unwrapPhase_bridging
  remove_ramp.py  090214_101120.unw  -m maskTempCoh.h5  -s quadratic
"""

def create_parser():
    parser = argparse.ArgumentParser(description='Remove phase ramp',
                                     formatter_class=argparse.RawTextHelpFormatter,
                                     epilog=TEMPLATE + '\n' + EXAMPLE)

    parser.add_argument('file', help='File for ramp removal')
    parser.add_argument('-m', '--mask', dest='mask_file', default='maskTempCoh.h5',
                        help='mask for pixels used in ramp estimation\n' +
                             'default - maskTempCoh.h5\n' +
                             'no - use the whole area')
    parser.add_argument('-s', dest='surface_type', default='linear',
                        choices={'linear', 'quadratic',
                                 'linear_range', 'linear_azimuth',
                                 'quadratic_range', 'quadratic_azimuth'},
                        help='type of surface/ramp to remove, linear by default')
    parser.add_argument('-d','--dset', dest='dset', 
                        help='dataset name to be derampped in ifgramStack file\n' + 
                             'e.g.: unwrapPhase\n' +
                             '      unwrapPhase_bridging')
    parser.add_argument('-o', '--outfile', help='Output file name.')
    parser.add_argument('--update', dest='update_mode', action='store_true',
                        help='Enable update mode, and skip inversion if:\n'+
                             '1) output file already exists, readable '+
                             'and newer than input file\n' +
                             '2) all configuration parameters are the same.')
    return parser


def cmd_line_parse(iargs=None):
    parser = create_parser()
    inps = parser.parse_args(args=iargs)

    if not inps.outfile:
        inps.outfile = '{}_ramp.h5'.format(os.path.splitext(inps.file)[0])
    return inps


def run_or_skip(inps):
    print('-'*50)
    print('update mode: ON')
    flag = 'skip'

    # check output file
    if not os.path.isfile(inps.outfile):
        flag = 'run'
        print('1) output file {} NOT found.'.format(inps.outfile))
    else:
        print('1) output file {} already exists.'.format(inps.outfile))
        infiles = [inps.file]
        if inps.mask_file:
            infiles.append(inps.mask_file)
        ti = max(os.path.getmtime(i) for i in infiles)
        to = os.path.getmtime(inps.outfile)
        if ti > to:
            flag = 'run'
            print('2) output file is NOT newer than input file: {}.'.format(infiles))
        else:
            print('2) output file is newer than input file: {}.'.format(infiles))

    # check configuration
    if flag == 'skip':
        iDict = {}
        iDict['mintpy.deramp'] = inps.surface_type
        iDict['mintpy.deramp.maskFile'] = inps.mask_file
        atr = readfile.read_attribute(inps.outfile)
        if any(str(iDict[key]) != atr.get(key, 'None') for key in configKeys):
            flag = 'run'
            print('3) NOT all key configration parameters are the same:{}'.format(configKeys))
        else:
            print('3) all key configuration parameters are the same:{}'.format(configKeys))

    # result
    print('run or skip: {}.'.format(flag))
    return flag


###########################################################################################
def main(iargs=None):
    inps = cmd_line_parse(iargs)

    # --update option
    if inps.update_mode and run_or_skip(inps) == 'skip':
        return inps.outfile

    out_file = ut.run_deramp(inps.file,
                             ramp_type=inps.surface_type,
                             mask_file=inps.mask_file,
                             out_file=inps.outfile,
                             datasetName=inps.dset)

    # config parameter
    print('add/update the following configuration metadata to file:\n{}'.format(configKeys))
    atr_new = {}
    atr_new['mintpy.deramp'] = inps.surface_type
    atr_new['mintpy.deramp.maskFile'] = inps.mask_file
    ut.add_attribute(out_file, atr_new)
    return


###########################################################################################
if __name__ == '__main__':
    main()