# Author: Heresh Fattahi

import os
import sys
import reader


# A dictionary to help with reading the data when more than one band exists
bandsDict = {

             'ISCE-unwrapped-phase' : [2] , 
             'ISCE-unwrapped-amplitude' : [1], 
             'ISCE-wrapped' : [1], 
             'ISCE-incidence' : [1], 
             'ISCE-heading':[2],
             'ISCE-offset-azimuth':[1],
             'ISCE-offset-range':[2],             
             'ISCE-offset-snr':[1],
}

class insarPair:
    """
     InsarPair object for a single InSAR pair.

    """
    def __init__(self, name='insarPair', dates=None, observation={}, quality={}, geometry={}, metadata=None):

        self.referenceDate, self.secondaryDate = dates
        #######################################
        
        self.observationsDict = observation
        self.qualityDict = quality
        self.geometryDict = geometry

        self.platform = 'platform'
        self.track = 'track'
        self.processor = None

        # platform, track and processor can get values from metadat if they exist   
        if metadata is not None:
           for key , value in metadata.items():
              setattr(self, key, value)
    
    def read(self,family):

        self.get_metadata(family)
        bands_key = self.processor + '-' + family
        if bands_key in bandsDict.keys(): 
           bands = bandsDict[bands_key] 
        else:
           bands = None
        data = reader.read(self.file , self.processor, bands=bands)
        return data, self.metadata

    def get_metadata(self,family):

        if family in self.observationsDict.keys():
           self.file = self.observationsDict[family]
        elif family in self.qualityDict.keys():
           self.file = self.qualityDict[family]
        elif family in self.geometryDict.keys():
           self.file = self.geometryDict[family]
        else:
           self.file = ''
        #else:
        #   '''error message''' 
        ############################
        # if the processor is not known, find the processor based on the file extension
        if self.processor is None:
           
           ext = self.file.split('.')[-1]
           if os.path.exists(self.file+'.xml'):
               self.processor = 'ISCE' 
           elif os.path.exists(self.file+'.rsc'):
               self.processor = 'ROI_PAC'
           elif os.path.exists(self.file+'.par'):
               self.processor = 'GAMMA'
           elif os.path.exists(self.file+'.par'):
               self.processor = 'GAMMA'
           elif ext == 'grd':
               self.processor = 'GMT'
           #what for DORIS

        if os.path.exists(self.file):
           self.metadata = reader.read_metadata(self.file, self.processor)
           self.length = int(self.metadata['LENGTH'])
           self.width = int(self.metadata['WIDTH']) 
        else:
           self.metadata = {}
           self.length = 0
           self.width = 0

        if self.platform is None and  'platform' in self.metadata.keys():
             self.platform = self.metadata['platform']
       
        if self.track is None and  'track' in self.metadata.keys():
             self.track = self.metadata['track'] 

        self.platform_track = self.platform + '-' + self.track
             
        if self.processor is None:
             if  'processor' in self.metadata.keys():
                  self.processor = self.metadata['processor']               
             else:
                  self.processor = 'ISCE'