'''
Created on Set 10, 2017

@author: Juan C. Espinoza
'''


import os
import sys
import time
import glob
import datetime

import numpy

from schainpy.model.proc.jroproc_base import ProcessingUnit
from schainpy.model.data.jrodata import Parameters
from schainpy.model.io.jroIO_base import JRODataReader, isNumber
from schainpy.utils import log

FILE_HEADER_STRUCTURE = numpy.dtype([
    ('year', 'f'),
    ('doy', 'f'),
    ('nint', 'f'),
    ('navg', 'f'),
    ('fh', 'f'),
    ('dh', 'f'),
    ('nheights', 'f'),    
    ('ipp', 'f')
])

REC_HEADER_STRUCTURE = numpy.dtype([
    ('magic', 'f'),
    ('hours', 'f'),
    ('timedelta', 'f'),
    ('h0', 'f'),
    ('nheights', 'f'),
    ('snr1', 'f'),
    ('snr2', 'f'),
    ('snr', 'f'),
])

DATA_STRUCTURE = numpy.dtype([
    ('range', '<u4'),
    ('status', '<u4'),
    ('zonal', '<f4'),
    ('meridional', '<f4'),
    ('vertical', '<f4'),
    ('zonal_a', '<f4'),
    ('meridional_a', '<f4'),
    ('corrected_fading', '<f4'),  # seconds
    ('uncorrected_fading', '<f4'),  # seconds
    ('time_diff', '<f4'),
    ('major_axis', '<f4'),
    ('axial_ratio', '<f4'),
    ('orientation', '<f4'),
    ('sea_power', '<u4'),
    ('sea_algorithm', '<u4')
])


class JULIAParamReader(JRODataReader, ProcessingUnit):
    '''
    Julia data (eej, spf, 150km) *.dat files
    '''

    ext = '.dat'

    def __init__(self, **kwargs):

        ProcessingUnit.__init__(self, **kwargs)

        self.dataOut = Parameters()
        self.counter_records = 0
        self.flagNoMoreFiles = 0
        self.isConfig = False
        self.filename = None
        self.clockpulse = 0.15
        self.kd = 213.6

    def setup(self,
              path=None,
              startDate=None,
              endDate=None,
              ext=None,              
              startTime=datetime.time(0, 0, 0),
              endTime=datetime.time(23, 59, 59),
              timezone=0,
              format=None,
              **kwargs):

        self.path = path
        self.startDate = startDate
        self.endDate = endDate
        self.startTime = startTime
        self.endTime = endTime
        self.datatime = datetime.datetime(1900, 1, 1)
        self.format = format

        if self.path is None:
            raise ValueError, "The path is not valid"

        if ext is None:
            ext = self.ext

        self.search_files(self.path, startDate, endDate, ext)
        self.timezone = timezone
        self.fileIndex = 0

        if not self.fileList:
            log.warning('There is no files matching these date in the folder: {}'.format(
                path), self.name)

        self.setNextFile()

    def search_files(self, path, startDate, endDate, ext):
        '''
         Searching for BLTR rawdata file in path
         Creating a list of file to proces included in [startDate,endDate]

         Input: 
             path - Path to find BLTR rawdata files
             startDate - Select file from this date
             enDate - Select file until this date
             ext - Extension of the file to read
        '''
        
        log.success('Searching files in {} '.format(path), self.name)        
        fileList0 = glob.glob1(path, '{}*{}'.format(self.format.upper(), ext))
        fileList0.sort()

        self.fileList = []
        self.dateFileList = []

        for thisFile in fileList0:            
            year = thisFile[2:4]
            if not isNumber(year):
                continue

            month = thisFile[4:6]
            if not isNumber(month):
                continue

            day = thisFile[6:8]
            if not isNumber(day):
                continue

            year, month, day = int(year), int(month), int(day)
            dateFile = datetime.date(year+2000, month, day)
            
            if (startDate > dateFile) or (endDate < dateFile):
                continue

            self.fileList.append(thisFile)
            self.dateFileList.append(dateFile)
        
        return

    def setNextFile(self):

        file_id = self.fileIndex

        if file_id == len(self.fileList):
            log.success('No more files in the folder', self.name)
            self.flagNoMoreFiles = 1
            return 0
        
        log.success('Opening {}'.format(self.fileList[file_id]), self.name)
        filename = os.path.join(self.path, self.fileList[file_id])

        dirname, name = os.path.split(filename)        
        self.siteFile = name.split('.')[0]
        if self.filename is not None:
            self.fp.close()
        self.filename = filename
        self.fp = open(self.filename, 'rb')
        self.t0 = [7, 0, 0]
        self.tf = [18, 0, 0]
        
        self.header_file = numpy.fromfile(self.fp, FILE_HEADER_STRUCTURE, 1)
        yy = self.header_file['year'] - 1900 * (self.header_file['year'] > 3000)
        self.year = int(yy + 1900 * (yy < 1000))
        self.doy = int(self.header_file['doy'])
        self.H0 = self.clockpulse*numpy.round(self.header_file['fh']/self.clockpulse)
        self.dH = self.clockpulse*numpy.round(self.header_file['dh']/self.clockpulse)        
        self.ipp = self.clockpulse*numpy.round(self.header_file['ipp']/self.clockpulse)        
        
        tau = self.ipp / 1.5E5        
        
        self.nheights = int(self.header_file['nheights'])
        self.heights = numpy.arange(self.nheights) * self.dH + self.H0    

        self.sizeOfFile = os.path.getsize(self.filename)
        self.counter_records = 0
        self.flagIsNewFile = 0
        self.fileIndex += 1

        return 1

    def readNextBlock(self):

        while True:
            if self.fp.tell() == self.sizeOfFile:
                self.flagIsNewFile = 1
                if not self.setNextFile():
                    return 0

            self.readBlock()

            if (self.datatime < datetime.datetime.combine(self.startDate, self.startTime)) or \
               (self.datatime > datetime.datetime.combine(self.endDate, self.endTime)):
                log.warning(
                    'Reading Record No. {} -> {} [Skipping]'.format(
                        self.counter_records,
                        self.datatime.ctime()),
                    self.name)
                continue
            break

        log.log('Reading Record No. {} -> {}'.format(
            self.counter_records,
            self.datatime.ctime()), self.name)

        return 1

    def readBlock(self):
        
        header_rec = numpy.fromfile(self.fp, REC_HEADER_STRUCTURE, 1)
        self.timedelta = header_rec['timedelta']
        if header_rec['magic'] == 888.:
            h0 = self.clockpulse * numpy.round(header_rec['h0'] / self.clockpulse)
            nheights = int(header_rec['nheights'])            
            hours = float(header_rec['hours'][0])            
            self.datatime = datetime.datetime(self.year, 1, 1) + datetime.timedelta(days=self.doy-1, hours=hours)
            self.time = (self.datatime - datetime.datetime(1970,1,1)).total_seconds()
            
            buffer = numpy.fromfile(self.fp, 'f', 8*nheights).reshape(nheights, 8)
            idh0 = int(numpy.round((self.H0 - h0) / self.dH))
            if idh0 == 0 and buffer[0,0] > 1E8: 
                buffer[0,0] = buffer[1,0]
            
            pow0 = buffer[:, 0]
            pow1 = buffer[:, 1]
            acf0 = (buffer[:,2] + buffer[:,3]*1j) / pow0
            acf1 = (buffer[:,4] + buffer[:,5]*1j) / pow1
            dccf = (buffer[:,6] + buffer[:,7]*1j) / (pow0*pow1)

            ### SNR
            sno = (pow0 + pow1 - header_rec['snr']) / header_rec['snr']
            sno10 = numpy.log10(sno)
            dsno = 1.0 / numpy.sqrt(self.header_file['nint'] * self.header_file['navg']) * (1 + (1 / sno))
            
            ### Vertical Drift
            sp = numpy.sqrt(numpy.abs(acf0)*numpy.abs(acf1))
            sp[numpy.where(numpy.abs(sp) >= 1.0)] = numpy.sqrt(0.9999)
                        
            vzo = -numpy.arctan2(acf0.imag + acf1.imag,acf0.real + acf1.real)*1.5E5*1.5/(self.ipp*numpy.pi)
            dvzo = numpy.sqrt(1.0 - sp*sp)*0.338*1.5E5/(numpy.sqrt(self.header_file['nint']*self.header_file['navg'])*sp*self.ipp)            
            err = numpy.where(dvzo <= 0.1)
            dvzo[err] = 0.1

            #Zonal Drifts
            dt = self.header_file['nint']*self.ipp / 1.5E5
            coh = numpy.sqrt(numpy.abs(dccf))
            err = numpy.where(coh >= 1.0)            
            coh[err] = numpy.sqrt(0.99999)
                
            err = numpy.where(coh <= 0.1)
            coh[err] = numpy.sqrt(0.1)
                    
            vxo = numpy.arctan2(dccf.imag, dccf.real)*self.heights[idh0]*1.0E3/(self.kd*dt)
            dvxo = numpy.sqrt(1.0 - coh*coh)*self.heights[idh0]*1.0E3/(numpy.sqrt(self.header_file['nint']*self.header_file['navg'])*coh*self.kd*dt)
            
            err = numpy.where(dvxo <= 0.1)            
            dvxo[err] = 0.1
            
            N = range(len(pow0))

            self.buffer = numpy.zeros((6, self.nheights)) + numpy.nan

            self.buffer[0, idh0+numpy.array(N)] = sno10
            self.buffer[1, idh0+numpy.array(N)] = vzo
            self.buffer[2, idh0+numpy.array(N)] = vxo            
            self.buffer[3, idh0+numpy.array(N)] = dvzo
            self.buffer[4, idh0+numpy.array(N)] = dvxo
            self.buffer[5, idh0+numpy.array(N)] = dsno

            self.counter_records += 1

        return

    def readHeader(self):
        '''
        RecordHeader of BLTR rawdata file
        '''

        header_structure = numpy.dtype(
            REC_HEADER_STRUCTURE.descr + [
                ('antenna_coord', 'f4', (2, self.nchannels)),
                ('rx_gains', 'u4', (self.nchannels,)),
                ('rx_analysis', 'u4', (self.nchannels,))
            ]
        )

        self.header_rec = numpy.fromfile(self.fp, header_structure, 1)
        self.lat = self.header_rec['lat'][0]
        self.lon = self.header_rec['lon'][0]
        self.delta = self.header_rec['delta_r'][0]
        self.correction = self.header_rec['dmode_rngcorr'][0]
        self.imode = self.header_rec['dmode_index'][0]
        self.antenna = self.header_rec['antenna_coord']
        self.rx_gains = self.header_rec['rx_gains']        
        self.time = self.header_rec['time'][0]               
        dt = datetime.datetime.utcfromtimestamp(self.time)
        if dt.date()>self.datatime.date():
            self.flagDiscontinuousBlock = 1
        self.datatime = dt
        
    def readData(self):
        '''
        Reading and filtering data block record of BLTR rawdata file, filtering is according to status_value.

        Input:
            status_value - Array data is set to NAN for values that are not equal to status_value

        '''

        data_structure = numpy.dtype(
            DATA_STRUCTURE.descr + [
                ('rx_saturation', 'u4', (self.nchannels,)),
                ('chan_offset', 'u4', (2 * self.nchannels,)),
                ('rx_amp', 'u4', (self.nchannels,)),
                ('rx_snr', 'f4', (self.nchannels,)),
                ('cross_snr', 'f4', (self.kchan,)),
                ('sea_power_relative', 'f4', (self.kchan,))]
        )

        data = numpy.fromfile(self.fp, data_structure, self.nranges)

        height = data['range']
        winds = numpy.array(
            (data['zonal'], data['meridional'], data['vertical']))
        snr = data['rx_snr'].T

        winds[numpy.where(winds == -9999.)] = numpy.nan
        winds[:, numpy.where(data['status'] != self.status_value)] = numpy.nan
        snr[numpy.where(snr == -9999.)] = numpy.nan
        snr[:, numpy.where(data['status'] != self.status_value)] = numpy.nan
        snr = numpy.power(10, snr / 10)

        return height, winds, snr

    def set_output(self):
        '''
        Storing data from databuffer to dataOut object
        '''

        self.dataOut.data_SNR = self.buffer[0]
        self.dataOut.heights = self.heights
        self.dataOut.data_param = self.buffer[1:,]
        self.dataOut.utctimeInit = self.time
        self.dataOut.utctime = self.dataOut.utctimeInit
        self.dataOut.useLocalTime = False
        self.dataOut.paramInterval = self.timedelta
        self.dataOut.timezone = self.timezone        
        self.dataOut.sizeOfFile = self.sizeOfFile
        self.dataOut.flagNoData = False
        self.dataOut.flagDiscontinuousBlock = self.flagDiscontinuousBlock

    def getData(self):
        '''
        Storing data from databuffer to dataOut object
        '''
        if self.flagNoMoreFiles:
            self.dataOut.flagNoData = True
            log.success('No file left to process', self.name)
            return 0

        if not self.readNextBlock():
            self.dataOut.flagNoData = True
            return 0

        self.set_output()

        return 1