**********  July 6th colorsv2.cgi (Version 2 of colors.cgi  **********   

#!/usr/bin/perl -w

use CGI qw(:standard);

# Written by Mark Jacobson on Thursday July 5th, 2001
# colors.cgi version 2 ---> colorsv2.cgi
# Illustrates Subroutines (Chapter 13), aka Functions (Hour 8)

#  Array @c1 is used for the BGCOLOR value 
#  Array @c2 is used to the TEXT color value

@c1 = qw(Red  Green  Blue Black Purple Yellow White Pink Orange Brown);
@c2 = qw(Blue Yellow Yellow White Yellow Purple Black Black Black Pink);

($bgColor, $textColor, $recentColors) = &getColors;

print header,
      start_html(-title   => "BGColor $bgColor, Text Color $textColor",
                 -BGCOLOR => "$bgColor",
                 -TEXT    => "$textColor"),

      h1("This has background color $bgColor and text color $textColor"),

      start_form,
         "<INPUT TYPE='hidden' NAME='recentcolors' VALUE=$recentColors>",
         submit('Random Color'),
      end_form;

      if ($recentColors =~ m/:/)
      {
         $recentCount = $recentColors =~ tr/://;
         print "\n<P><HR><H2>Previous $recentCount (BGCOLOR,TEXT) color pairs:"
               . "\n<OL>\n";
         @c = split (/:/, $recentColors);
         for ($i = 1; $i <= $recentCount; $i++)
         {
            $colorCode = $c[$i];
            print "<LI>($c1[$colorCode],$c2[$colorCode])<P>\n";
         }      
         print "\n</OL></H2>\n";
      }

print end_html;

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

sub getColors
{
   $REPEAT_LENGTH = 6;

   srand;

   @c1 = qw(Red  Green  Blue Black Purple Yellow White Pink Orange Brown);
   @c2 = qw(Blue Yellow Yellow White Yellow Purple Black Black Black Pink);

   if (param())
   {
      $recently = param('recentcolors');
      @c = split (/:/, $recently);

      do {
         $whichColor = int (rand(@c1));
         $repeat = 0;

         for ($i=0; $i<@c; $i++) 
         {
            if ($whichColor == $c[$i])
            {
               $repeat = 1;
            }
         }   

      } while ($repeat == 1);

      unshift (@c, $whichColor);
      if (@c > $REPEAT_LENGTH)
      {
         pop @c;      
      }
      $recentColors = join(":", @c);
   }
   else
   {
      $whichColor = int (rand(@c1));
      $recentColors = $whichColor;
   }

   return ( $c1[$whichColor], $c2[$whichColor], $recentColors );
}