#!/usr/bin/env python3

'''Parse the SEG-D file(created by SeaMAP GunLink4000

to extract the external header for all inormation

about source array and guns' firing'''

# # # protype made 18th June 2016

import os

import glob

from construct import String

#BINARYFILE = '2016-03-23.04-08-58.0907.segd'

GUNSTRINGS = 4

GUNSTOTALNUM = 64

GUN_STR_OFSET = 90+GUNSTRINGS*4

GUNS = list(range(GUNSTOTALNUM))

SEGD_FOLD = "F:/Faxian6_Backups/programming/2016YQ/"

os.chdir(SEGD_FOLD)

LINES = glob.glob('2016YQ*')

for LINE in LINES:

BINARYSAVE = "E:/mypython/"+LINE+"GLK4K_SEG-D_ExtHedSAVE02.txt"

os.chdir(SEGD_FOLD+LINE+"/")

SEGD_LIST = glob.glob('*.segd')

for SEGD_SHOTFILE in SEGD_LIST:

#print(SEGD_SHOTFILE)

BINARYFILE = SEGD_SHOTFILE

FD = open(BINARYFILE, 'rb')

SAVE = open(BINARYSAVE, 'at')#file appended ,text mode

FD.seek(96) #omit the first 96 bytes on begining of SEG-D file

BINDATA = FD.read(1514) #define the external header's length

BINSTR = String(1514, encoding="utf8").parse(BINDATA)

# print(BINSTR)

'''The offset 0 to 90 contained

the fixed GCS90(SYNTRAK) header information'''

SAVE.write('ID:'+BINSTR[0:6]+\

';Size:'+BINSTR[6:10]+'bytes'+\

';Line:'+BINSTR[10:18]+\

';ShotPoint:'+str(int(BINSTR[18:28]))+\

';ArrayMask:'+BINSTR[28:30]+\

';TriggerMode:'+BINSTR[30:31]+\

';GPS ShotDate:'+BINSTR[31:39]+\

';GPS ShotTime:'+BINSTR[40:48]+\

';Current Sequence:'+BINSTR[48:49]+\

';Strings:'+BINSTR[49:50]+\

';Guns in Array:'+BINSTR[50:52]+\

';Active Guns:'+BINSTR[52:54]+\

';DeltaError Guns:'+BINSTR[54:56]+\

';AutoFire Guns:'+BINSTR[56:58]+\

';MissFire Guns:'+BINSTR[58:60]+\

';Spread:'+BINSTR[60:63]+\

';VolumeFired(C.I.):'+BINSTR[63:68]+\

';AverAbsErr(ms):'+BINSTR[68:73]+\

';StdDevErr(ms):'+BINSTR[73:78]+\

';Spare:'+BINSTR[78:82]+\

';ManifoldPres(PSI):'+BINSTR[82:86]+\

';Deep Tow:'+'Used for time micro seconds'\

)

'''The each gun string's air pressure values'''

for string in range(GUNSTRINGS):

SAVE.write(';GunString No.'+str(string)+' Pres.:'+\

BINSTR[(90+string*4):(94+string*4)])

'''The each single gun's firing detail'''

'''(GUN_STR_OFSET+6)one Byte with BLANK'''

for GUN in GUNS:

SAVE.write(';GunPortNo.:'+BINSTR[(GUN_STR_OFSET+GUN*22):\

(GUN_STR_OFSET+2+GUN*22)]+\

';GunMode:'+BINSTR[(GUN_STR_OFSET+2+GUN*22):\

(GUN_STR_OFSET+3+GUN*22)]+\

';DetectMode:'+BINSTR[(GUN_STR_OFSET+3+GUN*22):\

(GUN_STR_OFSET+4+GUN*22)]+\

';Sequence(SOURCE)No.:'+BINSTR[(GUN_STR_OFSET+4+GUN*22):\

(GUN_STR_OFSET+5+GUN*22)]+\

';AutoFire:'+BINSTR[(GUN_STR_OFSET+5+GUN*22):\

(GUN_STR_OFSET+6+GUN*22)]+\

';Static Offset(ms):'+str((int(BINSTR[(GUN_STR_OFSET+7+GUN*22):\

(GUN_STR_OFSET+10+GUN*22)]))/10)+\

';GunDelay(ms):'+str((int(BINSTR[(GUN_STR_OFSET+10+GUN*22):\

(GUN_STR_OFSET+13+GUN*22)]))/10)+\

';FireTime(ms):'+str((int(BINSTR[(GUN_STR_OFSET+13+GUN*22):\

(GUN_STR_OFSET+16+GUN*22)]))/10)+\

';DeltaErrTime(ms):'+str((int(BINSTR[(GUN_STR_OFSET+16+GUN*22):\

(GUN_STR_OFSET+19+GUN*22)]))/10)+\

';Depth(meter):'+str((int(BINSTR[(GUN_STR_OFSET+19+GUN*22):\

(GUN_STR_OFSET+22+GUN*22)]))/10)\

)

SAVE.write('\n')

FD.close()

SAVE.close()