#!/usr/bin/perl
use FileHandle;
use File::Basename;
use FILE::Path;
use Getopt::Long;

$scd = 1.0;		#image display intensity scale factor
$expd = 0.4;		#image display exponent
$ext = "bmp";		#default image extension BMP
$n_ovr = 4;

GetOptions ('e=f' => \$expd, 's=f' => \$scd, 'b' => \$ext_flg, 'q' => \$qflg, 'p' => \$pix_flg, 'c' => \$cal_flg, 'j' => \$ls_flg);

if (($#ARGV + 1) < 5){die <<EOS;}
*** Preprocessing of a set of ASF SLC images using par_ASF_SLC
*** Copyright 2014, Gamma Remote Sensing, v1.5 6-May-2014 cw/km ***
*** RTC Processing of ASF SLC products ***

usage: $0 <CEOS_list> <DEM> <DEM_par> <mode> <GEO_dir> <log>
    CEOS_list	(input) 2 column list of CEOS format SLC image products
		  1. CEOS format SLC image data (*.D, IMG*)
                  2. CEOS format leader file (*.L, LED*)
    DEM         (input) input DEM
    DEM_par     (input) input DEM parameter file
    mode        processing mode:
                  0: read in CEOS format data from different Sensors (PALSAR, ERS-1, ERS-2, JERS-1, Radarsat-1)
                  1: perform geocoding and pixel area correction
    GEO_dir     directory to store geocoded results
    log         (output) processing log file

    -s scale     (option) set image display scale factor (default: $scd)   
    -e exp       (option) set image display exponent (default: $expd)
    -b           (option) set raster image type to SUN raster (default: $ext)
    -q           (option) quiet mode, run through with no display
    -p           (option) use pixel area program to generate simulated SAR image in range-doppler coordinates
    -c           (option) generate calibrated image products
    -j           (option) do not use layover-shadow map in call to pixel_area
    -o n_ovr     (option) offset estimation patch over-sampling factor (default:4)

  NOTE: Each frame listed in the CEOS_list must be in a separate directory. The same DEM is used for all images in
  the CEOS_list
EOS

$options =" -o $n_ovr -e $expd -s $scd";   #set the oversampling factor for offset matching to 4
if($ext_flg == 1){$options = $options." -b";}   #set to Sun Raster, BMP is default
if($qflg == 1)   {$options = $options." -q";}
if($pix_flg == 1){$options = $options." -p";}
if($cal_flg == 1){$options = $options." -c";}
if($ls_flg == 1) {$options = $options." -j";}  #do not use lay-over/shadow mask when running pixel_area within mk_geo_radcal

open(SLIST, "<$ARGV[0]") or die "ERROR $0: ASF CEOS format SLC list does not exist: $ARGV[0]\n";
$dem = $ARGV[1];
$dem_par =$ARGV[2];
my ($dem_name, $dir1, $ext1) = fileparse($dem, qr/\.[^.]*/); #extension is the last bit after the last period 

$mode = $ARGV[3];
($mode == 0 || $mode == 1) or die "ERROR: invalid value for mode: $ARGV[3]\n";

print "ASF_GEO_proc options: $options\n";

LINE: while (<SLIST>) {		#read list of directories with unreformated SLC data
  $time = localtime;
  chomp $_;
  next LINE if /^$/; 		#skip blank lines in input list
  next LINE if /^#/; 		#skip comments in the input list
  @fields = split;		#extract data file name
  $ceos_data = $fields[0];
  $ceos_ldr = $fields[1];
  my ($s1, $dir1, $ext1) = fileparse($ceos_data, qr/\.[^.]*/); #extension is the last bit after the last period 
  print "\nCEOS data file: $ceos_data    CEOS leader file: $ceos_ldr\n";
  
  $log = $dir1.$ARGV[5];
  open(LOG,">$log") or die "ERROR $0: cannot open log file: $log\n";
  print LOG "$0 @ARGV\n\n";	#print command line that was used
  print "PROCESSING START: $time\n\n";
  print LOG "PROCESSING START: $time\n\n";
  close LOG;
  
  my @ceos_params = ldr_parse("$ceos_ldr");	#parse CEOS leader file
  $id = $ceos_params[2];
  $satellite = $ceos_params[1];
  $beam = $ceos_params[4];
  $adc = $ceos_params[5];
  print "radar beam: $beam   ADC rate: $adc\n";
  
  $geo_dir = $ARGV[4];
  if ($ceos_params[1] eq "ALOS"){
    $id_tmp = $id;
    if ($s1 =~ /IMG-([HV][HV])/){   #match H or V and return math in $1
      $id = $id_tmp."_$1";
      $geo_dir = $geo_dir."_$1";
    }
  }
  
  $slc = "$dir1".$id.".slc";
  $slc_par = "$dir1".$id.".slc.par";
  $mli = "$dir1".$id.".mli";
  $mli_par = "$dir1".$id.".mli.par";

  print "SLC image: $slc     SLC parameter file: $slc_par\n";
  print "MLI image: $mli     MLI parameter file: $mli_par\n";
  
  if ($mode == 0){
    if($ceos_params[1] eq "RSAT-1"){
      execute("par_RSAT_SLC $ceos_ldr $slc_par $ceos_data $slc 60.0", $log);
      if ($id =~ /_FN/){
        execute("multi_look $slc $slc_par $mli $mli_par 2 2",$log);
      }
      else {
        execute("multi_look $slc $slc_par $mli $mli_par 1 4",$log);
      }
    }
    elsif ($ceos_params[1] eq "ALOS"){
    
      execute("par_EORC_PALSAR $ceos_ldr $slc_par $ceos_data $slc", $log);
      if ($adc eq "16.000"){
        execute("multi_look $slc $slc_par $mli $mli_par 1 4",$log);
      }
      else {
        execute("multi_look $slc $slc_par $mli $mli_par 1 2",$log);
      }
    }
    else {  #ERS-1, ERS-2, JERS-1
      execute("par_ASF_SLC $ceos_ldr $slc_par $ceos_data $slc",$log);
      if($satellite eq "JERS-1"){
        execute("multi_look $slc $slc_par $mli $mli_par 1 3",$log);
      }
      else{  #ERS-1, ERS-2
        execute("multi_look $slc $slc_par $mli $mli_par 1 5",$log);
     }
    }
    @width = extract_param($mli_par, "range_samples:");
    execute("raspwr $mli $width[1] 1 0 1 1 $scd $expd 1 $mli".".$ext", $log);
  }
  else {
    $dem_seg = "$dir1".$geo_dir."\/".$dem_name."_seg.dem";
    $dem_seg_par = $dem_seg."_par";
    $geo_dir1 = $dir1.$geo_dir;
    
    print "DEM segment name: $dem_seg  DEM segment parameter file $dem_seg_par\n";
    
    if($ceos_params[1] eq "RSAT-1"){
      if ($id =~ /_FN/){
        $post = 6.944444e-5;  #1/4 arc-sec
      }
      else {
        $post = 1.388888e-4;  #1/2 arc-sec
      }
    }
    elsif ($ceos_params[1] eq "ALOS"){
      if ($adc eq "16.000"){
        $post = 1.388888e-4;  #1/2 arc-sec
      }
      else {
        $post = 6.944444e-5;  #1/4 arc sec
      }  #1/2 arc-sec
    }
    else {  #ERS-1, ERS-2, JERS-1
      if($satellite eq "JERS-1"){
        $post = 1.388888e-4;  #1/2 arc-sec
      }
      else{  #ERS-1, ERS-2
        $post = 1.388888e-4;  #1/2 arc-sec
     }
    }
    
    $cmd = "mk_geo_radcal $mli $mli_par $dem $dem_par $dem_seg $dem_seg_par $geo_dir1 $id $post";
    execute($cmd." 0 2 $options", $log);
    eval {
      execute($cmd." 1 2 $options", $log);
    } or do {
      print "ASF_GEO_proc mode 1: Determination of the initial offset failed, skipping initial offset for $mli\n";
    };
    eval {
      execute($cmd." 2 2 $options", $log);
    } or do {
       print "ASF_GEO_proc mode2: Failed to determine offset model for $mli\n";
       next LINE;
    };
    execute($cmd." 3 2 $options", $log);
  }
}

$time = localtime;
print "\nPROCESSING END: $time\n";
print LOG "\nPROCESSING END: $time\n";
exit 0;

sub extract_param{
  my ($infile,$keyword) = @_;
  open(PAR_IN,$infile) || die "ERROR $0: cannot open parameter file: $infile\n";

  while(<PAR_IN>){
    chomp;
    @tokens = split;
    if($tokens[0] eq $keyword){close PAR_IN; return @tokens;}
  }
  close PAR_IN;
  die "ERROR $0: keyword $keyword not found in file: $infile\n";
}

sub execute{
  my ($command, $log) = @_;
  print "$command\n";
  print LOG ("\n${command}\n");
  close LOG;
  $exit = system("$command 1>> $log 2>&1");
  $exit == 0 or die "ERROR $0: non-zero exit status: $command\n";
  if (-e $log){
    open(LOG,">>$log") or die "ERROR $0: cannot open log file: $log\n";
  }
  else {
    open(LOG,">$log") or die "ERROR : cannot open log file: $log\n";
  }
  LOG->autoflush;
}

sub ldr_parse {
  my ($infile)=@_;		# Get passed parameters
  open (INPUT, "$infile") or die "ERROR: opening CEOS leader file: $infile\n";
  binmode INPUT;

  my ($process, $satellite);
  my ($buf, @parms);
  
  read (INPUT, $buf, 4096);
  $process = substr($buf, 31, 9);
  $process =~ s/^\s+//;    #remove leading whitespace
  $process =~ s/\s+$//;    #remove trailing whitespace
  
  $satellite = substr($buf, 1116, 6);
  $satellite =~ s/^\s+//;
  $satellite =~ s/\s+$//;
  
  $id=substr($buf, 740, 24);
  $id =~ s/^\s+//; 
  $id =~ s/\s+$//;
  
  $date = substr($buf, 788, 8);
  close (INPUT);
  print "Processor : $process  Satellite: $satellite  ID: $id  Date: $date\n";
  
  $beam = substr($buf, 2488, 3);
  $adc = substr($buf, 1436, 6);
  
  @parms=("$process", "$satellite", "$id", "$date", "$beam", "$adc");
  return @parms;
}