#!/usr/bin/perl -w
# RWB  June 22, 2001
# This is a Perl script read in, sift, and analyze a lot of data from
# the USCG VTM system.  It will copy data from CD ROM to disk, unzip the
# files, extract ferry files (for the Marin, for now), scan for ferry
# runs and calculate various quantities.  The file sequence (the
# example is data from april 25, 2001) is:
#	h:\2001\04\april2001.zip to hard disk (must be done from Windows)
#	april2001.zip to 20010425.log  (unzip)
#       20010425.log to mar10425.log   (sortvtm: Marin only)
#	mar10425.log to mar10425.dat   (scanvtm; calcvtm)
   use strict;
   my @mname=('january','february','march','april','may','june','july',
      'august','september','october','november','december');
   my @ndays=(31,28,31,30,31,30,31,31,30,31,30,31);
   my $iy1=2001; # first year (can be changed interactively)
   my $im10=1;    # first month (ditto)
   my $iy2=2001; # last year (ditto)
   my $im20=1;    # last month (ditto)
   my $iday10=1;    # first day (ditto)
   my $iday20=1;    # last day (ditto)
   my $iunzip=0;    # flag for unpkzip (ditto)
   my $isort=0;     # flag for sortvtm (ditto)
   my $iscan=0;     # flag for scanvtm (ditto)
   my $icalc=0;     # flag for calcvtm (ditto)
   my $idellog=0;   # flag for dlog (ditto)
   my $idelzip=0;   # flag for dzip (ditto)
   my ($im,$im1,$im2,$iy,$id);
   my ($iya,$ima,$imb,$id1,$id2);

   askval(); # Set parameters interactively.

   ###### Unzip data and sort out the data for the Marin, by PST days.
   $im1=$im10; # correct first time around.
   $im2=$12; # correct until last year.
   for ($iy=$iy1; $iy <= $iy2; $iy++) {
      if($iy!=$iy1) {$im1=1;} # Replace special first month.
      if($iy==$iy2) {$im2=$im20;} # Put in special last month.
      for($im=$im1; $im <= $im2; $im++) {
         unpkzip($iy,$im); # Unzip a month's VTM loggings. 
      }
      $iya=$iy; # One year at a time.
      $ima=$im1;
      $imb=$im2;
   }
   sortvtm(); # sort out Marin files by PST days.

   ###### Scan for ferry runs, and carry out calculations; save results
   ###### in WDSK (IDL) format.
   $im1=$im10; # correct first time around.
   $id1=$iday10; # correct first time around.
   $im2=$12; # correct until last year.
   for ($iy=$iy1; $iy <= $iy2; $iy++) {
      if($iy!=$iy1) {$im1=1;} # Replace special first month.
      if($iy==$iy2) {$im2=$im20;} # Put in special last month.
      for($im=$im1; $im <= $im2; $im++) {
	 if( $iy!=$iy1||$im!=$im1 ) { $id1=1; } # Replace special first day.
	 $id2=$ndays[$im-1];
	 if($im==2&&$iy%4==0) { $id2++; }
	 if( $iy==$iy2&&$im==$im20) { $id2=$iday20; } # Put in special last day.
	 for($id=$id1; $id <= $id2; $id++) {
	    scancalc(); # Call IDL to scan and calculate.
	    if( $idellog ne 0) { dlog(); } # Delete log files for all ships.
         }
	 if( $idelzip ne 0) { dzip(); } # Delete zip file.
      }
   }
### END of main script.

#	Subroutine to prompt for dates and drive letter.
sub askval() {
   print "This PERL script looks for USCG VTM-system data on the CD-ROM\n";
   print "drive, and copies it to /d4/Darmat/data/naut/vtm, making\n";
   print "subdirectories as needed.  Then the file is unziped,\n";
   print "sorted, and scanned for ferry runs, and calculations for\n";
   print "the ferry runs are carried out.\n";
   my $a;
   
   print "\$iy1,\$iy2,\$im10,\$im20,\$iday10,\$iday20 = $iy1, $iy2, $im10,
      $im20, $iday10, $iday20\n";

   print "first year:     $iy1: ";
   $a=<STDIN>;
   chomp($a);
   if(length($a) gt 0) {$iy1=$a,$iy2=$a};

   print "first month:    $im10: ";
   $a=<STDIN>;
   chomp($a);
   if(length($a) gt 0) {$im10=$a,$im20=$a};

   print "first day:      $iday10: ";
   $a=<STDIN>;
   chomp($a);
   if(length($a) gt 0) {$iday10=$a;$iday20=$a;}
   if($iday10==1) {$iday20=$ndays[$im10-1];}

   print "last year:      $iy2: ";
   $a=<STDIN>;
   chomp($a);
   if(length($a) gt 0) {$iy2=$a;}

   print "last month:     $im20: ";
   $a=<STDIN>;
   chomp($a);
   if(length($a) gt 0) {$im20=$a;}
   if($iy2!=$iy1||$im20!=$im10) {$iday20=$ndays[$im20-1];}

   print "last day:       $iday20: ";
   $a=<STDIN>;
   chomp($a);
   if(length($a) gt 0) {$iday20=$a};

   print "iunzip (0->don't unzip):            $iunzip: ";
   $a=<STDIN>;
   chomp($a);
   if(length($a) gt 0) {$iunzip=$a};

   print "isort (0->don't sort):              $isort: ";
   $a=<STDIN>;
   chomp($a);
   if(length($a) gt 0) {$isort=$a};

   print "iscan (0->don't scan):              $iscan: ";
   $a=<STDIN>;
   chomp($a);
   if(length($a) gt 0) {$iscan=$a};

   print "icalc (0->don't calc):              $icalc: ";
   $a=<STDIN>;
   chomp($a);
   if(length($a) gt 0) {$icalc=$a};

   print "idellog (0->don't delete):          $idellog: ";
   $a=<STDIN>;
   chomp($a);
   if(length($a) gt 0) {$idellog=$a};

   print "idelzip (0->don't delete):          $idelzip: ";
   $a=<STDIN>;
   chomp($a);
   if(length($a) gt 0) {$idelzip=$a};

   print "\$iy1,\$iy2,\$im10,\$im20,\$iday10,\$iday20 = 
      $iy1, $iy2, $im10, $im20, $iday10, $iday20\n";
   print "\$iunzip, \$isort, \$iscan, \$icalc, \$idellog, \idelzip = 
      $iunzip, $isort, $iscan, $icalc, $idellog, $idelzip\n";
      
} ### END of subroutine ask()

#  Subroutine to unzip a month of logged ship records.
sub unpkzip() {
   my ($infn, $expath);
   if( !$iunzip ) { return 0; }
   $infn='/d4/Darmat/data/naut/vtm/'.sprintf("%4d",$iy).'/'.
      sprintf("%02d",$im).'/'.$mname[$im-1].sprintf("%4d",$iy).'.zip';
   $expath=substr($infn,0,32);
   print "\$infn = $infn\n\$expath = $expath\n";
   if( !(-e $infn) ) { return 0; }
   system("unzip $infn -d $expath"); # Unzip one month of data.
   return 1;
} ### END of sub inpkzip()

#  Subroutine to spawn the IDL job which sorts out Marin data,
#  sortvtm.pro.  The variables $iya, $ima, and $imb are inherited
#  from the calling script.  Only data from a single year is
# processed in one call.
sub sortvtm() {
   if( !$isort ) { return 0; }
   open( TEMP,'>ptemp1.tmp' );
   print TEMP "sortvtm,".sprintf("%d,%d,%d,%d,%d,%d\n",$iy1,$iy2,$im10,
      $im20,$iday10,$iday20)."exit\n";
   close( TEMP );
   system("idl ptemp1.tmp"); # Call IDL to sort data.
   unlink( "ptemp1.tmp" );
   return 1;
} ### END of sub sortvtm()

#  Subroutine to spawn the IDL jobs to scan Marin files for ferry runs
#  and to carry out calculations.  Each call to this subroutine handles
#  one day's data.
sub scancalc() {
   my $stat1=0;
   my $stat2=0;

   if( $iscan ) {
      open( TEMP,'>ptemp1.tmp' );
      print TEMP "scanvtm,".sprintf("%d,%d,%d\n",$iya,$ima,$id)."exit\nn";
      close( TEMP );
      $stat1=system("idl ptemp1.tmp"); # Call IDL to sort data.
      unlink( "ptemp1.tmp" );
   }

   if( $icalc ) {
      open( TEMP,'>ptemp1.tmp' );
      print TEMP "calcvtm,".sprintf("%d,%d,%d\n",$iya,$ima,$id)."exit\nn";
      close( TEMP );
      $stat2=system("idl ptemp1.tmp"); # Call IDL to sort data.
      unlink( "ptemp1.tmp" );
   }

   return $stat1*$stat2;
} ### END of sub sortvtm()

#  Subroutines to delete the large files with information for all boats
#  in the Bay, after use.  The date information $iy, $im and $id are
#  inherited from the main script, as well as a list of names of months.
sub dlog() {
   my ($filename,$status);
   $status=0;
   $filename='/d4/Darmat/data/naut/vtm/'.sprintf("%04d",$iy).'/'.
      sprintf("%02d",$im).'/'.sprintf("%04d%02d%02d",$iy,$im,$id).
      '.log';
   if(-e $filename) {$status=unlink $filename;}
   print "Deleting $filename, status = $status\n";
   return $status;
} # End of sub dlog()

sub dzip() {
   my ($filename,$status);
   $status=0;
   $filename='/d4/Darmat/data/naut/vtm/'.sprintf("%04d",$iy).'/'.
      sprintf("%02d",$im).'/'.$mname[$im-1].sprintf("%04d",$iy).
      '.zip';
   if(-e $filename) {$status=unlink $filename;}
   print "Deleting $filename, status = $status\n";
   return $status;
} # End of sub dzip()