#!/usr/bin/perl

use warnings;
use strict;

=head1 NAME

 exchange-tk.pl - A tool to calculate the calories in diabetes exchanges.

=head1 SYNOPSIS

 exchange-tk.pl [options]
 Options:
        --help           brief help message
        --man            full documentation

This is a Perl-Tk program so it is GUI and visual. Enter the exchanges
and press the Compute button to do the calculations.

=head1 VERSION

 author   David Myers
 date     February 11, 2009
 modified N/A

=head1 DESCRIPTION

 exchange-tk.pl - A tool to calculate the calories in diabetes exchanges.

=head1 COPYRIGHT

 This program is copyrighted (C) 2010 by David Myers. All rights are
 reserved.

 This program is licensed under the terms of the the Artistic License 
 version 2.0. A copy of the license can be found at this URL:

 http://www.opensource.org/licenses/artistic-license-2.0.php

=head1 BUGS

  In Ubuntu, you may have to

  export XMODIFIERS=""

  to get this code to work.

  for more details, see the bug documented here:
  https://bugs.launchpad.net/ubuntu/+source/perl-tk/+bug/283806

=cut


use English;
use Tk;
use Getopt::Long;
use Pod::Usage;

my $help = 0;
my $man  = 0;

GetOptions(
    'help|?' => \$help,
    man      => \$man,
) or pod2usage(2);

pod2usage( -exitval => 0, -verbose => 1 ) if $help;
pod2usage( -exitval => 0, -verbose => 2 ) if $man;


my $Version = "0.11";

my $debug = 0;


#
# calories/gram list
#

my $cal_fat     = 9.0;
my $cal_protein = 4.0;
my $cal_carb    = 4.0;
my $cal_alcohol = 7.0;

# exchange diet groups

my @exc_map = (
    "",               "starch",    "fruit",      "skim_milk",
    "one_milk",       "two_milk",  "whole_milk", "veggies",
    "very_lean_meat", "lean_meat", "fat_meat",   "very_fat_meat",
    "fats",
);

my %exchange_groups = (
    starch         => [ "Starch",         15, 3, 1, 80 ],
    fruit          => [ "Fruits",         15, 0, 0, 60 ],
    skim_milk      => [ "Skim Milk",      12, 8, 0, 90 ],
    one_milk       => [ "1% Milk",        12, 8, 1, 100 ],
    two_milk       => [ "2% Milk",        12, 8, 3, 120 ],
    whole_milk     => [ "Whole Milk",     12, 8, 5, 150 ],
    veggies        => [ "Vegetables",     5,  2, 0, 25 ],
    very_lean_meat => [ "Very Lean Meat", 0,  7, 1, 35 ],
    lean_meat      => [ "Lean Meat",      0,  7, 3, 55 ],
    fat_meat       => [ "Med Fat Meat",   0,  7, 5, 75 ],
    very_fat_meat  => [ "Very Fat Meat",  0,  7, 8, 100 ],
    fats           => [ "Fats",           0,  0, 5, 45 ],
);

my $main = MainWindow->new();
$main->title("Diabetic Exchange Calculator V $Version");
$main->configure( -background => 'cyan' );

# Build Frames and Widgets

my $top = $main->Frame( -background => 'cyan' )->grid();

my $menuframe =
  $top->Frame( -background => 'cyan' )
  ->grid( -row => 0, -column => 0, -sticky => 'w' );

my $dataframe =
  $top->Frame( -background => 'cyan' )
  ->grid( -row => 0, -column => 1, -sticky => 'w' );

my $go = $menuframe->Button(
    -text       => "Compute",
    -background => 'white',
    -command    => \&compute
);

$go->grid( -row => 0, -column => 0, -sticky => 'w' );

for my $fill ( 1 .. 13 ) {

    my $fill_text = $menuframe->Label( -text => '   ', -background => 'cyan' );
    $fill_text->grid( -row => $fill, -column => 0, -sticky => 'w' );

}

my $stop = $menuframe->Button(
    -text       => 'Quit',
    -background => 'red',
    -command    => sub { exit(0) }
);

$stop->grid( -row => 14, -column => 0, -sticky => 'w' );

my @column_labels = (
    "Category", "Servings", "Carbs (g)", "Proteins (g)",
    "Fats (g)", "Calories"
);

for my $col_lbl ( 0 .. 5 ) {
    my $col_txt = $dataframe->Label(
        -text       => $column_labels[$col_lbl],
        -background => 'cyan'
    );

    $col_txt->grid( -row => 0, -column => $col_lbl, -sticky => 'w' );
}

my @rowlabels = (
    "",                                  $exchange_groups{starch}[0],
    $exchange_groups{fruit}[0],          $exchange_groups{skim_milk}[0],
    $exchange_groups{one_milk}[0],       $exchange_groups{two_milk}[0],
    $exchange_groups{whole_milk}[0],     $exchange_groups{veggies}[0],
    $exchange_groups{very_lean_meat}[0], $exchange_groups{lean_meat}[0],
    $exchange_groups{fat_meat}[0],       $exchange_groups{very_fat_meat}[0],
    $exchange_groups{fats}[0],           "Total",
    "Percent Calories"
);

for my $row ( 1 .. 14 ) {
    my $row_txt = $dataframe->Label(
        -text       => $rowlabels[$row],
        -background => 'cyan'
    );
    $row_txt->grid( -row => $row, -column => 0, -sticky => 'w' );
}

my @serving       = ();
my @serving_value = ();
for my $row ( 1 .. 12 ) {
    $serving_value[$row] = "0";
    $serving[$row]       = $dataframe->Entry(
        -width        => 4,
        -background   => 'white',
        -state        => 'normal',
        -textvariable => \$serving_value[$row]
    );
    $serving[$row]->grid( -row => $row, -column => '1', -pady => 1 );
}

my @carbs_obj   = ();
my @carbs_value = ();
for my $row ( 1 .. 12 ) {
    $carbs_value[$row] =
      $serving_value[$row] * $exchange_groups{ $exc_map[$row] }[1];
    $carbs_obj[$row] = $dataframe->Label(
        -background   => 'cyan',
        -state        => 'normal',
        -textvariable => \$carbs_value[$row]
    );
    $carbs_obj[$row]->grid(
        -row    => $row,
        -column => '2',
        -pady   => 1
    );
}

my @protein_obj   = ();
my @protein_value = ();
for my $row ( 1 .. 12 ) {
    $protein_value[$row] =
      $serving_value[$row] * $exchange_groups{ $exc_map[$row] }[2];
    $protein_obj[$row] = $dataframe->Label(
        -background   => 'cyan',
        -state        => 'normal',
        -textvariable => \$protein_value[$row]
    );
    $protein_obj[$row]->grid(
        -row    => $row,
        -column => '3',
        -pady   => 1
    );
}

my @fat_obj   = ();
my @fat_value = ();
for my $row ( 1 .. 12 ) {
    $fat_value[$row] =
      $serving_value[$row] * $exchange_groups{ $exc_map[$row] }[3];
    $fat_obj[$row] = $dataframe->Label(
        -background   => 'cyan',
        -state        => 'normal',
        -textvariable => \$fat_value[$row]
    );
    $fat_obj[$row]->grid(
        -row    => $row,
        -column => '4',
        -pady   => 1
    );
}

my @cal_obj   = ();
my @cal_value = ();
for my $row ( 1 .. 12 ) {
    $cal_value[$row] =
      $serving_value[$row] * $exchange_groups{ $exc_map[$row] }[4];
    $cal_obj[$row] = $dataframe->Label(
        -background   => 'cyan',
        -state        => 'normal',
        -textvariable => \$cal_value[$row]
    );
    $cal_obj[$row]->grid(
        -row    => $row,
        -column => '5',
        -pady   => 1
    );
}

my @total_obj   = ();
my @total_value = ();
for my $col ( 2 .. 5 ) {
    $total_value[$col] = "    ";
    $total_obj[$col]   = $dataframe->Label(
        -background   => 'cyan',
        -state        => 'normal',
        -textvariable => \$total_value[$col]
    );
    $total_obj[$col]->grid(
        -row    => 13,
        -column => $col,
        -pady   => 1
    );
}

my @pct_obj   = ();
my @pct_value = ();
for my $col ( 2 .. 5 ) {
    $pct_value[$col] = "    ";
    $pct_obj[$col]   = $dataframe->Label(
        -background   => 'cyan',
        -state        => 'normal',
        -textvariable => \$pct_value[$col]
    );
    $pct_obj[$col]->grid(
        -row    => 14,
        -column => $col,
        -pady   => 1
    );
}

#
# functions to compute totals and percentages.
#

sub compute_starch {
    for my $row ( 1 .. 12 ) {
        $carbs_value[$row] =
          $serving_value[$row] * $exchange_groups{ $exc_map[$row] }[1];
    }
}

sub compute_protein {
    for my $row ( 1 .. 12 ) {
        $protein_value[$row] =
          $serving_value[$row] * $exchange_groups{ $exc_map[$row] }[2];
    }
}

sub compute_fat {
    for my $row ( 1 .. 12 ) {
        $fat_value[$row] =
          $serving_value[$row] * $exchange_groups{ $exc_map[$row] }[3];
    }
}

sub compute_calories {
    for my $row ( 1 .. 12 ) {
        $cal_value[$row] =
          $serving_value[$row] * $exchange_groups{ $exc_map[$row] }[4];
    }
}

sub compute_total {
    my $sum;
    $sum = 0;
    for my $row ( 1 .. 12 ) {
        $sum += $carbs_value[$row];
    }
    $total_value[2] = $sum;
    $sum = 0;
    for my $row ( 1 .. 12 ) {
        $sum += $protein_value[$row];
    }
    $total_value[3] = $sum;
    $sum = 0;
    for my $row ( 1 .. 12 ) {
        $sum += $fat_value[$row];
    }
    $total_value[4] = $sum;
    $sum = 0;
    for my $row ( 1 .. 12 ) {
        $sum += $cal_value[$row];
    }
    $total_value[5] = $sum;
}

sub compute_pct {
    my $total = $total_value[5] || 1; 
    my $pct = $total_value[2] * $cal_carb * 100.0 / $total;
    $pct_value[2] = sprintf( "%4.1f", $pct ) . "%";
    $pct = $total_value[3] * $cal_protein * 100.0 / $total;
    $pct_value[3] = sprintf( "%4.1f", $pct ) . "%";
    $pct = $total_value[4] * $cal_fat * 100.0 / $total;
    $pct_value[4] = sprintf( "%4.1f", $pct ) . "%";

}

# button press to bind them all.

sub compute {
    compute_starch();
    compute_protein();
    compute_fat();
    compute_calories();
    compute_total();
    compute_pct();
}

MainLoop();