#!/usr/bin/perl
### make_raw_envisat.pl

use Env qw(INT_SCR INT_BIN SAR_IDL_DIR OUR_SCR VOR_DIR INS_DIR PS_BIN);
use lib "$INT_SCR";  #### Location of Generic.pm
use Generic;

###Usage info/check
sub Usage{

`$INT_SCR/pod2man.pl  $PS_BIN/make_raw_envisat.pl`;
exit 1;
}
@ARGV >= 1  or Usage();
@args = @ARGV;

$rawdata        = shift;
#$frame          = shift;
$orbit_type     = "HDR";
#$Lstart         = shift;
#$Lend           = shift;
#$Pstart         = shift;
#$Pend           = shift;

#################
Message "Checking I/O";
#################
@Infiles  = ($rawdata, $auxdata, $orbdata);
#@Outfiles = ("$date.raw",  "$date.raw.rsc");
#&IOcheck(\@Infiles);
Log ("make_raw_envisat.pl", @args);

##ERS GENERAL DIFINITIONS###
#
#$C                        = 299792458;
## new value
 $ONE_WAY_DELAY            = 3.4449923715353358e-06;
## old value
##$ONE_WAY_DELAY            = -2.0168e-06;
#$RANGE_SAMPLING_FREQUENCY = 18.950420e6;
#$ANTENNA_SIDE             = -1;
#$ANTENNA_LENGTH           = 12;
#$SEC_PER_PRI_COUNT        = 210.94e-09;
#
################
## FR 20020903
#$ANTENNA_LENGTH           = 10;
#
################
##Soren's paper
#$RANGE_SAMPLING_FREQUENCY = 18.962468e6;
#$SEC_PER_PRI_COUNT        = 210.943006e-9;
#$ONE_WAY_DELAY            = 6.622e-6 / 2;
##chirp_length 37.12e-6
##chirp bandwidth 15.50829e6;
#
#$PLANET_GM       = 3.98600448073E+14;
#$PLANET_SPINRATE = 7.29211573052E-05;
#
###END ERS GENERAL DEFINITIONS

###ENVISAT GENERAL DIFINITIONS

#$ONE_WAY_DELAY            = 

$ANTENNA_SIDE             = -1;
# value from handbook (Eric Fielding))
$ANTENNA_LENGTH_hndbk           = 10;
#from read_raw.pro
#$ANTENNA_LENGTH           = 11.1;
$chirp_slope              = 5.88741157e11;

$PLANET_GM                = 3.98600448073E+14;
$PLANET_SPINRATE          = 7.29211573052E-05;
$C                        = 299792458;
$pi                       = atan2(1,1)*4;
$r2d                      = 180/$pi;   


$ae                       = 6378137;  #WGS84 reference ellipsoid
$flat                     = 1./298.257223563;

#$sat                      = ENVISAT;
$sat                      = ERS1; #trick


###END ENVISAT GENERAL DEFINITIONS
 open(RAW,$rawdata);
 for ($i=1; $i<65; $i++) {
   ($name,$value) = split /\=/,<RAW>;
   chomp($value);
   #Message "Name: $name";
   #Message "Value: $value";
   if ($name eq "PRODUCT") {@tmp = split /\_/,$value; $orbnum=$tmp[7]; ($unkn,$foo)=split /\./,$tmp[8];}
   if ($name eq "SWATH") {($foo,$swath)=split /\"/,$value;}
   if ($name eq "SENSING_START") {($foo,$sense_st)=split /\"/,$value;}
   if ($name eq "SENSING_STOP") {($foo,$sense_sp)=split /\"/,$value;}
   if ($name eq "PROC_CENTER") {($foo,$proc_center)=split /\"/,$value;}
 }
 close(RAW);
($year,$month,$day,$first_line_utc)= split /\:/, Date_to_UTC($sense_st);

$yr=$year;
$yr =~ s/^(..)(..)$/\2/;

$date = $year.$month.$day;
$shortdate = $yr.$month.$day;

($foo,$foo,$foo,$last_line_utc)= split /\:/, Date_to_UTC($sense_sp);

$header = $date."_".$orbnum."_".$unkn."_".$swath;

#######
Message "Retrieving Orbit file from $VOR_DIR";
#######
@files = `ls -1 $VOR_DIR/DOR_VOR*`;
chomp($orbdata = Get_Filename($sense_st, $sense_sp, @files));
Message "Using orbit file: $orbdata";
if (!$orbdata) {Message "Orbit file was not found in $VOR_DIR";exit 1;}

#######
Message "Retrieving Instrument file from $INS_DIR";
#######
@files = `ls -1 $INS_DIR/ASA_INS*`;
chomp($auxdata = Get_Filename($sense_st, $sense_sp, @files));
Message "Using Instrument file: $auxdata";
if (!$auxdata) {Message "Instrument file was not found in $INS_DIR";exit 1;}
  
#############################
Message "Running IDL script";
#############################

$datfile=$header."_raw_byte.dat";
  
if (-s $shortdate.".raw") {
  Message "$shortdate.raw already exists, NOT RUNNING READ_RAW";
} else {
  $read_raw_args = "/dumpbyte, filename=\"".$rawdata."\", auxname=\"".$auxdata."\"";
#  $read_raw_args = "/dumpbyte, /debug, filename=\"".$rawdata."\", auxname=\"/data/pkgs6/SAR/ENVISAT_IDL/ASA_INS_AXVIEC20030424_154116_20030428_000000_20031231_235959\"";
  Message "read_raw,par,$read_raw_args";
  open(ARGUS,">read_raw.in");
  print ARGUS "read_raw,par,".$read_raw_args;
  print ARGUS "\nexit\n";
  close(ARGUS);
  system "$SAR_IDL_DIR/idl read_raw.in";
  if (-s $datfile) {
    system "/bin/mv $datfile $shortdate.raw";
  } else {
    Message "read_raw failed, $datfile does not exist";
    exit 1;
  }
}

$mphfile=$header."_mph.txt";
$logfile=$header."_log.txt";
$focusfile=$header."_focusing.in";
$hdrfile="hdr_data_points_".$shortdate.".rsc";

#if (-s $mphfile && -s $datfile && -s $focusfile){
if (-s $mphfile && -s $focusfile){


################################
Message "Writing the imagery resource file";
################################

$center_utc     = ($first_line_utc+$last_line_utc)/2;

($foo, $cn_ms) = split /\./, $center_utc;
while (length($cn_ms) < 3) {$cn_ms .="0";}
$cn_s = ($center_utc - ($cn_ms/1000))%60;
while (length($cn_s) < 2) {$cn_s ="0".$cn_s;}
$cn_mn = (($center_utc - ($cn_ms/1000) - $cn_s)/60)%60;
while (length($cn_mn) < 2) {$cn_mn ="0".$cn_mn;}
$cn_hr = (($center_utc - ($cn_ms/1000) - $cn_s)/60 - $cn_mn)/60;
while (length($cn_hr) < 2) {$cn_hr ="0".$cn_hr;}

#Use_rsc "$shortdate.raw write FIRST_FRAME                    $frame";
Use_rsc "$shortdate.raw write FIRST_FRAME_SCENE_CENTER_TIME  $year$month$day$cn_hr$cn_mn$cn_s$cn_ms";
Use_rsc "$shortdate.raw write FIRST_FRAME_SCENE_CENTER_LINE  000";
Use_rsc "$shortdate.raw write DATE                           $shortdate";
Use_rsc "$shortdate.raw write FIRST_LINE_YEAR                $year";
Use_rsc "$shortdate.raw write FIRST_LINE_MONTH_OF_YEAR       $month";
Use_rsc "$shortdate.raw write FIRST_LINE_DAY_OF_MONTH        $day";
Use_rsc "$shortdate.raw write FIRST_CENTER_HOUR_OF_DAY       $cn_hr";
Use_rsc "$shortdate.raw write FIRST_CENTER_MN_OF_HOUR        $cn_mn";
Use_rsc "$shortdate.raw write FIRST_CENTER_S_OF_MN           $cn_s";
Use_rsc "$shortdate.raw write FIRST_CENTER_MS_OF_S           $cn_ms";
Use_rsc "$shortdate.raw write PROCESSING_FACILITY            $proc_center";


 open(FOCUS,$focusfile);
$foo = <FOCUS>;
$foo = <FOCUS>;
$foo = <FOCUS>;
$width = <FOCUS>;
$foo = <FOCUS>;
$foo = <FOCUS>;
$wavelength = <FOCUS>;
$fsamp_hz = <FOCUS>;
$chirp_hz = <FOCUS>;
$ANTENNA_LENGTH = <FOCUS>;
$foo = <FOCUS>;
$pulse_length = <FOCUS>;
$prf = <FOCUS>;
$two_way_delay = <FOCUS>;
$length = <FOCUS>; 
$foo = <FOCUS>;
$foo = <FOCUS>;
$foo = <FOCUS>;
$ibias = <FOCUS>;
$qbias = $ibias;
 close(FOCUS);

$Lstart or $Lstart = 1;
$Lend or $Lend = $length;
$Pstart or $Pstart = 1;
$Pend or $Pend = $width;
$Pend = $Pend * 2;

$last_utc   = $first_line_utc+$length/$prf;

#Message "Original last line UTC: $last_line_utc  New last line UTC: $last_utc";

$starting_range = ($two_way_delay/2) * $C;
$range_pixel_size = $C / $fsamp_hz /2;

Use_rsc "$shortdate.raw write PLATFORM                 ENVISAT";
Use_rsc "$shortdate.raw write ORBIT_NUMBER             $orbnum"; 
Use_rsc "$shortdate.raw write STARTING_RANGE           $starting_range"; 
Use_rsc "$shortdate.raw write RANGE_PIXEL_SIZE         $range_pixel_size"; 
Use_rsc "$shortdate.raw write TWO_WAY_DELAY            $two_way_delay"; 
Use_rsc "$shortdate.raw write PRF                      $prf";
Use_rsc "$shortdate.raw write ANTENNA_SIDE             $ANTENNA_SIDE";
Use_rsc "$shortdate.raw write ANTENNA_LENGTH           $ANTENNA_LENGTH_hndbk";
Use_rsc "$shortdate.raw write FILE_LENGTH              $length";
Use_rsc "$shortdate.raw write XMIN                     $Pstart";
Use_rsc "$shortdate.raw write XMAX                     $Pend";
Use_rsc "$shortdate.raw write WIDTH                    $Pend";
Use_rsc "$shortdate.raw write YMIN                     $Lstart";
Use_rsc "$shortdate.raw write YMAX                     $Lend";
Use_rsc "$shortdate.raw write RANGE_SAMPLING_FREQUENCY $fsamp_hz";
Use_rsc "$shortdate.raw write PLANET_GM                $PLANET_GM";
Use_rsc "$shortdate.raw write PLANET_SPINRATE          $PLANET_SPINRATE";

######
Message "Reformating Orbit information into HDR style";
######
Get_Orbit_Data();

($q1,$q2,$Lat,$Lon,$height_mid, $x0, $y0, $z0, $vx0, $vy0,$vz0) = split /\s+/,
    `$INT_SCR/state_vector.pl $year$month$day $center_utc $sat $orbit_type $shortdate`;
Status "state_vector.pl";


if ($orbit_type eq "HDR"){
 $r     = sqrt($x0**2+$y0**2+$z0**2);
 $r1    = sqrt($x0**2+$y0**2);
 $Lat   = atan2($z0,$r1);
 $Lon   = atan2($y0,$x0);
 $H     = $r-$ae;
 for ($i=1; $i<7; $i++){
  $N      = $ae/(sqrt(1-$flat*(2-$flat)*sin($Lat)**2));
  $TanLat = $z0/$r1/(1-(2-$flat)*$flat*$N/($N+$H));
  $Lat    = atan2($TanLat,1);
  $H      = $r1/cos($Lat)-$N;
 }
 $height_mid=$H; 
}

$N    = $ae/sqrt(1-$flat*(2-$flat)*sin($Lat)**2);
$earth_radius_mid=$N;

$ve=-sin($Lon)*$vx0+cos($Lon)*$vy0;
$vn=-sin($Lat)*cos($Lon)*$vx0-sin($Lat)*sin($Lon)*$vy0+cos($Lat)*$vz0;
$hdg = atan2($ve,$vn);
$e2 = $flat*(2-$flat);
$M = $ae*(1-$e2)/(sqrt(1-$e2*sin($Lat)**2))**3;
$earth_radius_mid_old = $N*$M/($N*(cos($hdg))**2+$M*(sin($hdg))**2);
Message "old earthradius: $earth_radius_mid_old  new earthradius: $earth_radius_mid";

($q1,$q2,$q3,$q4,$height_top, $x0, $y0, $z0, $vx, $vy,$vz) = split /\s+/,
    `$INT_SCR/state_vector.pl $year$month$day $first_line_utc $sat $orbit_type $shortdate`;
Status "state_vector.pl";

if ($orbit_type eq "HDR"){
 $r     = sqrt($x0**2+$y0**2+$z0**2);
 $r1    = sqrt($x0**2+$y0**2);
 $Lat   = atan2($z0,$r1);
 $Lon   = atan2($y0,$x0);
 $H     = $r-$ae;
 for ($i=1; $i<7; $i++){
  $N      = $ae/(sqrt(1-$flat*(2-$flat)*sin($Lat)**2));
  $TanLat = $z0/$r1/(1-(2-$flat)*$flat*$N/($N+$H));
  $Lat    = atan2($TanLat,1);
  $H      = $r1/cos($Lat)-$N;
 }
 $height_top=$H; 
}

$height_dt=($height_mid-$height_top)/($center_utc-$first_line_utc);
if ($vz0 > 0) {$orbit_direction =  "ascending";}
else          {$orbit_direction = "descending";}
$velocity_mid=sqrt($vx0**2 + $vy0**2 + $vz0**2);
$Latd=$Lat*$r2d;
$Lond=$Lon*$r2d;
$hdgd=$hdg*$r2d;

Use_rsc "$shortdate.raw write FIRST_LINE_UTC  $first_line_utc"; 
Use_rsc "$shortdate.raw write CENTER_LINE_UTC $center_utc"; 
Use_rsc "$shortdate.raw write LAST_LINE_UTC   $last_line_utc"; 
Use_rsc "$shortdate.raw write HEIGHT       $height_top";
Use_rsc "$shortdate.raw write HEIGHT_DT    $height_dt";
Use_rsc "$shortdate.raw write VELOCITY     $velocity_mid";
Use_rsc "$shortdate.raw write LATITUDE     $Latd";
Use_rsc "$shortdate.raw write LONGITUDE    $Lond";
Use_rsc "$shortdate.raw write HEADING      $hdgd";
Use_rsc "$shortdate.raw write EARTH_RADIUS $earth_radius_mid";
Use_rsc "$shortdate.raw write ORBIT_DIRECTION $orbit_direction";
Use_rsc "$shortdate.raw write FILE_START      $file_start";
Use_rsc "$shortdate.raw write WAVELENGTH      $wavelength";
Use_rsc "$shortdate.raw write PULSE_LENGTH    $pulse_length";
Use_rsc "$shortdate.raw write CHIRP_SLOPE     $chirp_slope";
Use_rsc "$shortdate.raw write I_BIAS          $ibias";
Use_rsc "$shortdate.raw write Q_BIAS          $qbias";

###############################
Message "Doppler Computation"; 
###############################

#$line_0=100;
#$line_1=$length - 200;
#
#$dop_rng1=0;
#$dop_rng2=0;
#$dop_rng3=0;
#
#`$INT_BIN/dopiq <<end
#$shortdate.raw
#$width,$line_0,$line_1
#$i_bias,$prf
#end
#`;
#$DopUnwStr = `$INT_SCR/DopUnw.pl dop.out`;
#$DopUnwStr =~ /Quadratic doppler:\s+(\S+)\s+(\S+)\s+(\S+)/;
#@QuadDopCoeff = ( $1, $2, $3 );
#
#
#Use_rsc "$shortdate.raw write DOPPLER_RANGE0  $QuadDopCoeff[0]";
#Use_rsc "$shortdate.raw write DOPPLER_RANGE1  $QuadDopCoeff[1]";
#Use_rsc "$shortdate.raw write DOPPLER_RANGE2  $QuadDopCoeff[2]";
#Use_rsc "$shortdate.raw write DOPPLER_RANGE3  0.";

# use Eric Fielding's external routine
system "$OUR_SCR/scan_doppler.pl $shortdate $length";

#Scan_doppler.pl doesn't currently calculate squint, run these lines
#until it does
  $dopp0 = Use_rsc "$shortdate.raw read DOPPLER_RANGE0";
  $sin_theta = sqrt( 1 - ($height_top / $starting_range)**2 );
  $fd = $dopp0 * $prf;
  $sin_squint = $fd / ( 2 * $velocity_mid * $sin_theta ) * $wavelength;
  $squint_rad = atan2( $sin_squint, sqrt( 1 - $sin_squint ** 2 ) );
  $squint_deg = $squint_rad * $r2d;
  Use_rsc "$shortdate.raw write SQUINT          $squint_deg";
#Done with squint calculation

system "$INT_SCR/GetPeg.pl $shortdate.raw $orbit_type";

open PEGOUT, "$shortdate.peg.out";
while( defined( $Line = <PEGOUT> ) ){
	if( $Line =~ /Peg Lat\/Lon , H =\s+(\S+)\s+(\S+)\s+(\S+)/ ){
		$Latd = $1;
		$Lond = $2;
	}
	if( $Line =~ /Peg Heading =\s+(\S+)/ ){
		$hdgd = $1;
	}
	if( $Line =~ /Vertical Fit:\s+(\S+)\s+(\S+)\s+(\S+)/ ){
		@Height_poly = ( $1, $2, $3 );
	}
	if( $Line =~ /Platform SCH Velocity \(m\/s\):\s+(\S+)\s+(\S+)\s+(\S+)/ ){
		@VelocitySCH = ( $1, $2, $3 );
		$velocity_mid = Norm( @VelocitySCH );
	}
	if( $Line =~ /Platform SCH Acceleration \(m\/s\^2\):\s+(\S+)\s+(\S+)\s+(\S+)/ ){
		@AccelerationSCH = ( $1, $2, $3 );
	}
}

close PEGOUT;


Use_rsc "$shortdate.raw write HEIGHT       $Height_poly[0]";
Use_rsc "$shortdate.raw write HEIGHT_DS    $Height_poly[1]";
Use_rsc "$shortdate.raw write HEIGHT_DDS   $Height_poly[2]";
Use_rsc "$shortdate.raw write VELOCITY     $velocity_mid";
Use_rsc "$shortdate.raw write VELOCITY_S   $VelocitySCH[0]";
Use_rsc "$shortdate.raw write VELOCITY_C   $VelocitySCH[1]";
Use_rsc "$shortdate.raw write VELOCITY_H   $VelocitySCH[2]";
Use_rsc "$shortdate.raw write ACCELERATION_S   $AccelerationSCH[0]";
Use_rsc "$shortdate.raw write ACCELERATION_C   $AccelerationSCH[1]";
Use_rsc "$shortdate.raw write ACCELERATION_H   $AccelerationSCH[2]";
Use_rsc "$shortdate.raw write LATITUDE     $Latd";
Use_rsc "$shortdate.raw write LONGITUDE    $Lond";
Use_rsc "$shortdate.raw write HEADING      $hdgd";
Use_rsc "$shortdate.raw write RLOOKS           1";
Use_rsc "$shortdate.raw write ALOOKS           1";
Use_rsc "$shortdate.raw write BEAM             $swath";

} else {
  Message "IDL script did not complete successfully";
  exit 1;
}

exit 0;

sub Get_Orbit_Data() {
  local($date);
  local($input);
  local($i);
  local($j);
  local($sense_st);
  local($sense_sp);
  local($st_utc);
  local($sp_utc);
  local($orbnum);
  
  open(ORBIT,$orbdata);
  
  for ($i=1; $i<44; $i++) {
   ($name,$value) = split /\=/,<ORBIT>;
    chomp($value);
    if ($name eq "SENSING_START") {($foo,$sense_st)=split /\"/,$value;}
    if ($name eq "SENSING_STOP") {($foo,$sense_sp)=split /\"/,$value;}
    if ($name eq "NUM_DSD") {$j = $value*8;}
  }
  
  ($st_yr,$st_mon,$st_day,$st_utc) = split /\:/, Date_to_UTC($sense_st);
  ($sp_yr,$sp_mon,$sp_day,$sp_utc) = split /\:/, Date_to_UTC($sense_sp);

  CHECK_ORB_DATE: {
    if (($sp_yr < $year ) || ($st_yr > $year )) {Message "Orbit file is for wrong year"; exit 1;} 
    if ($sp_yr > $year ) {$sp_mon += 12};
    if ($st_yr < $year ) {$st_mon -= 12};
    if (($sp_mon < $month) || ($st_mon > $month)) {Message "Orbit file is for wrong month"; exit 1;} 
    if ($sp_mon > $month) {$sp_day += 31;}
    if ($st_mon < $month) {$sp_day -= 31;}
    if (($sp_day < $day) || ($st_day > $day)) {Message "Orbit file is for wrong day"; exit 1;}
    if ($sp_day > $day) {$sp_utc += 86400;}
    if ($st_day < $day) {$st_utc -= 86400;}
    if (($sp_utc < $first_line_utc) || ($st_utc > $last_line_utc)) {Message "Orbit file is for wrong time"; exit 1;}
  }
  
  for ($i; $i<44+$j; $i++) {
   ($name,$value) = split /\=/,<ORBIT>;
    chomp($value);
  }
  $i=0;
  while (<ORBIT>) {
    ($caldate, $time, $foo, $orbnum, $x, $y, $z, $vx, $vy, $vz, $foo) = split /\s+/;
    $input = $caldate." ".$time;
    ($orb_yr, $orb_mon, $orb_day,$utc_time) = split /\:/, Date_to_UTC($input);
    if ($orb_day == $day) {
      if (abs($utc_time - $center_utc) <= 175) {
        $buff[$i]=$utc_time." ".$x." ".$y." ".$z." ".$vx." ".$vy." ".$vz;  
        $i++; 
      }
    }
  }
  open(HDR,">$hdrfile");
  foreach $line (@buff) {print HDR "${line}\n";}
  close(HDR);
  close(ORBIT);
}

sub Get_Filename()
{
  local($datastart, $datastop, @files) = @_;
  local($orbpath, $orbname, $startdate, $stopdate);
  local($st_year, $st_mon, $st_day);

  ($dst_year,$dst_mon,$dst_day,$dst_utc)= split /\:/, Date_to_UTC($datastart);
  $dst_caldate = "$dst_year"."$dst_mon"."$dst_day";
  $dst_ddate = Date_to_DecDate($dst_caldate);
  ($dsp_year,$dsp_mon,$dsp_day,$dsp_utc)= split /\:/, Date_to_UTC($datastop);
  $dsp_caldate = "$dsp_year"."$dsp_mon"."$dsp_day";
  $dsp_ddate = Date_to_DecDate($dsp_caldate);
  
  foreach $file (@files) {
    ($foo,$foo,$foo,$foo,$orbstart, $orb_sttime, $orbstop, $orb_sptime)=split /\_/, $file;
    $sp_ddate = Date_to_DecDate($orbstop);
    if ($sp_ddate >= $dst_ddate) {
      $st_ddate = Date_to_DecDate($orbstart);
      if ($st_ddate <= $dsp_ddate) {
        if ($orbstop != $dsp_caldate && $orbstart != $dst_caldate) {$orbname=$file; last;}
        if ($orbstop == $dsp_caldate && $orb_sptime > $dsp_utc) {
          if  ($orbstart != $dst_caldate) {$orbname=$file; last;}
          if  ($orbstart == $dst_caldate && $orb_sttime < $dst_utc) {$orbname=$file; last;}
        }  
      }
    }
  }
return $orbname;
}
  
sub Date_to_UTC()
{
  local($full_date) = @_;
  local($caldate);
  local($time);
  local($date);
  local($mon);
  local($year);
  local($day);
  local($hr);
  local($mn);
  local($s);
  local($ms);
  local($time_utc);
  
  ($caldate,$time)=split /\ /,$full_date;
  ($day,$mon,$year)=split /\-/,$caldate;
  ($hr, $mn, $s)=split /\:/,$time;
  ($s, $ms)=split /\./,$s;
  $ms =~ s/^(\d{3})(\d*)$/\1/;

  MONTH: {
    if ($mon eq "JAN") {$mon="01";last MONTH;}
    if ($mon eq "FEB") {$mon="02";last MONTH;}
    if ($mon eq "MAR") {$mon="03";last MONTH;}
    if ($mon eq "APR") {$mon="04";last MONTH;}
    if ($mon eq "MAY") {$mon="05";last MONTH;}
    if ($mon eq "JUN") {$mon="06";last MONTH;}
    if ($mon eq "JUL") {$mon="07";last MONTH;}
    if ($mon eq "AUG") {$mon="08";last MONTH;}
    if ($mon eq "SEP") {$mon="09";last MONTH;}
    if ($mon eq "OCT") {$mon="10";last MONTH;}
    if ($mon eq "NOV") {$mon="11";last MONTH;}
    if ($mon eq "DEC") {$mon="12";last MONTH;}
  }
  $time_utc = ($hr * 3600) + ($mn * 60) + $s + $ms/1000;
  $output = $year.":".$mon.":".$day.":".$time_utc;
  return $output;	
}

sub Date_to_DecDate() 
{
  local($caldate) = @_;
  local($mon);
  local($year);
  local($day, $days);
  
  $_ = $caldate;
  s/^(.{4})(..)(..)$/\1\2\3/;
  ($year, $mon, $day) = ($1, $2, $3);
  DAYS_OF_MONTH: {
    if ($mon eq "01") {$days=0;last DAYS_OF_MONTH;}
    if ($mon eq "02") {$days=31;last DAYS_OF_MONTH;}
    if ($mon eq "03") {$days=59;last DAYS_OF_MONTH;}
    if ($mon eq "04") {$days=90;last DAYS_OF_MONTH;}
    if ($mon eq "05") {$days=120;last DAYS_OF_MONTH;}
    if ($mon eq "06") {$days=151;last DAYS_OF_MONTH;}
    if ($mon eq "07") {$days=181;last DAYS_OF_MONTH;}
    if ($mon eq "08") {$days=212;last DAYS_OF_MONTH;}
    if ($mon eq "09") {$days=243;last DAYS_OF_MONTH;}
    if ($mon eq "10") {$days=273;last DAYS_OF_MONTH;}
    if ($mon eq "11") {$days=304;last DAYS_OF_MONTH;}
    if ($mon eq "12") {$days=334;last DAYS_OF_MONTH;}
  }
  $julday = $days + $day;
  $div = 365;
  if ($year % 4 == 0 && $mon > 2) {$julday++;$div++}
  $decdate = $year+($julday/$div);
  return $decdate;
}


=pod

=head1 USAGE

B<make_raw_envisat.pl> I< rawdata_filename>

=head1 FUNCTION

Creates I<date>.raw and I<date>.raw.rsc from level 0 envisat data files

=head1 ROUTINES CALLED

idl read_raw

state_vector.pl

dopiq-new

GetPeg.pl

DopUnw.pl

=head1 CALLED BY

none

=head1 FILES USED

Level_0_Datafile

=head1 FILES CREATED

I<date>.raw

I<date>.raw.rsc

dop.out

=head1 HISTORY

Shell Script : Francois ROGEZ 96/98
Perl  Script : Rowena LOHMAN 04/18/98
Modifications: Frederic CRAMPE, Oct 21, 1998
Hacked for ENVISAT: Ingrid JOHANSON, Feb 19 2004

=head1 LAST UPDATE

Frederic CRAMPE, Oct 06, 1999

=cut