#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# Copyright 2014 California Institute of Technology. ALL RIGHTS RESERVED.
# 
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
# 
# http://www.apache.org/licenses/LICENSE-2.0
# 
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
# 
# United States Government Sponsorship acknowledged. This software is subject to
# U.S. export control laws and regulations and has been classified as 'EAR99 NLR'
# (No [Export] License Required except when exporting to an embargoed country,
# end user, or in support of a prohibited end use). By downloading this software,
# the user agrees to comply with all applicable U.S. export laws and regulations.
# The user has the responsibility to obtain export licenses, or other export
# authority as may be required before exporting this software to any 'EAR99'
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# Authors: Kosal Khun, Marco Lavalle
#~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~



# Comment: Adapted from InsarProc/runCoherence.py
import logging
import operator
import isceobj
import sys
import os

from iscesys.ImageUtil.ImageUtil import ImageUtil as IU
from mroipac.correlation.correlation import Correlation

logger = logging.getLogger('isce.isceProc.runCoherence')

## mapping from algorithm method to Correlation instance method name
CORRELATION_METHOD = {
    'phase_gradient' : operator.methodcaller('calculateEffectiveCorrelation'),
    'cchz_wave' : operator.methodcaller('calculateCorrelation')
    }

def runCoherence(self, method="phase_gradient"):
    # correlation method is checked here, to raise an error as soon as possible
    if method not in CORRELATION_METHOD.keys():
        sys.exit("Unrecognized correlation method in runCoherence: %s" % method)

    infos = {}
    for attribute in ['topophaseFlatFilename']:
        infos[attribute] = getattr(self._isce, attribute)

    stdWriter = self._stdWriter

    for sceneid1, sceneid2 in self._isce.selectedPairs:
        pair = (sceneid1, sceneid2)
        resampAmpImages = self._isce.resampAmpImages[pair]
        widthInt = self._isce.resampIntImages[pair][self._isce.refPol].getWidth()
        for pol in self._isce.selectedPols:
            ampImage = resampAmpImages[pol].copy(access_mode='read')
            sid = self._isce.formatname(pair, pol)
            infos['outputPath'] = os.path.join(self.getoutputdir(sceneid1, sceneid2), sid)
            catalog = isceobj.Catalog.createCatalog(self._isce.procDoc.name)
            run(method, ampImage, widthInt, infos, stdWriter, catalog=catalog, sceneid=sid)
            self._isce.procDoc.addAllFromCatalog(catalog)


def run(method, ampImage, widthInt, infos, stdWriter, catalog=None, sceneid='NO_ID'):
    logger.info("Calculating Coherence: %s" % sceneid)

    # Initialize the flattened inteferogram
    topoflatIntFilename = infos['outputPath'] + '.' + infos['topophaseFlatFilename']
    intImage = isceobj.createIntImage()
    intImage.setFilename(topoflatIntFilename)
    intImage.setWidth(widthInt)
    intImage.setAccessMode('read')
    intImage.createImage()

    # Create the coherence image
    cohFilename = topoflatIntFilename.replace('.flat', '.cor')
    cohImage = isceobj.createOffsetImage()
    cohImage.setFilename(cohFilename)
    cohImage.setWidth(widthInt)
    cohImage.setAccessMode('write')
    cohImage.createImage()

    cor = Correlation()
    cor.configure()
    cor.wireInputPort(name='interferogram', object=intImage)
    cor.wireInputPort(name='amplitude', object=ampImage)
    cor.wireOutputPort(name='correlation', object=cohImage)

    try:
        CORRELATION_METHOD[method](cor)
    except KeyError:
        print("Unrecognized correlation method")
        sys.exit(1)
        pass
    return None