#!/usr/bin/perl
# glucopilot2gnuplot
# Author: Shankar Chakkere <shankara@erols.com, schakkere@denro.com>
# Date: 12 Feb 1999
# Status: Working
# Abstract:
# This program will extract the information from the imported GlucoPilot text
# for ploting in Gnuplot or any other spread sheet.
# The Glucopilot export file is in reverse order, current ( last ) entry on top
# of the file. The data has to be filtered because it is difficult to plot using
# Gnuplot which needs just 2 colums of data. The program provides the switches to 
# filter according to the category ( Pre breakfast, Lunch, Dinner etc. ) with or 
# without from /to dates.
#
# History: 
#
# 5 march 1999 
# Add -c to filter file according to category
#
# 17 march 1999
# Add -f and -t to filter file according to `from date` to\or `to date`
#
# Note: Convert the GlucoPilot text to unix format before using on unix
#       machines ( reason CR/LF)
# Copyright (C) 1999 Shankar Chakkere
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
#
# Visit http://www.fsf.org for more information

##############################################################################

($#ARGV < 0 ) && &usage; #     $#ARGV -1 when no command line parameter

# Clear all flags
$cat = 0;
$from = 0;
$to = 0;

# Extract switches
while ($ARGV[0] =~ m/^-/)
 {                          
    $_= shift(@ARGV);
                                
    s/^-//;
        while (s/^.//)
         {                             
            if ($& eq 'c')
              {                         
                $cat = 1;                        
                $pattern = $ARGV[0];
                shift(@ARGV);
               }
            elsif ($& eq 'f')
               {
                $from = 1;
                $fromdate = $ARGV[0];
                shift(@ARGV);
                }
            elsif ($& eq 't')
               {
                $to = 1;
                $todate = $ARGV[0];
                shift(@ARGV);
                }
           else 
                {                                 
                &badusage("Unknown option \-$&\n");
                }                                        
          }                                    
  } #while ($ARGV[0] =~ m/^-/)

$file = $ARGV[0];
open(FILE, $file) || die "Can't open input file : $file";

$number = 0; # To count number of datas

# Print the Title
print "$0 extracted data ";
print " Category: $pattern" if $cat;
print " From: $fromdate" if $from;
print " To: $todate" if $to;
print "\n";

# Pass flag should be set to extract the data.
$pass = 0;
# Pass all if no flags
$pass = 1 if (!$to && !$from && !$cat);
# Pass from the start of the file till the 'from date'
$pass = 1 if ($from && !$to); 
# pass all if just category
$pass = 1 if ($cat && !$to && !$from) ; 
# Flag to indicate still in from date, this is needed to include all 
# data of `from date`
$inequal = 0;

while (<FILE>)
{      
     if(/^"/){
        chop(); # no CR/LF
        chop(); # remove extra " at the end
        ($date,$time,$type,$category,$level,$remarks) = (split(/","/));
        ($quote,$date)=split(/"/,$date); # Remove starting "

        # Filter `To date`
        # Note: `To date` comes first before `From date`.
        # because the list is in reverse order, current data first.

        if ($to && !$pass) # set pass flag if date is found
          {
          $pass = 1 if ($todate eq $date);
          }


        # Set stop flag (pass = 0)
        
        if ($from && $pass )
          {
          # pass while in equality
          $inequal = 1 if ($fromdate eq $date);
          $pass = 0 if (($fromdate ne $date) && $inequal);
          }

        if ($cat) # if -c
          {
          &pushdata if(($pass) && ($pattern eq $category));
          }
        else      #if -t or -f 
          {
          &pushdata if($pass);
          }
  }  # if(/^"/)
} # while (<FILE>

# Print the data 
# NOTE:GlucoPilot will store the current data on the top of the list
# and I don't know a way to tell Excel to reverse the table.

for ($i=1 ; $i <=$number ; $i++) 
   {
   print "$i $data2prn[$number - $i]";
   }

close FILE;

sub usage { 
    die <<EOF
$0 will extract the information from GlucoPilot-export-file for ploting.
       Usage: $0 [-c] Category [-f] date [-t] date GlucoPilot-export-file
       Where:
         -c[ategory] will filter the data according to category.
         -f[rom] date.
         -t[o] date.
EOF
}

sub badusage
 {
    print STDERR $_[0];           
    &usage;                       
    exit 1;                       
}                                 

sub  pushdata
  {
    push(@data2prn,"$date $level\n");
    $number = $number + 1; #The serial number
  }