#!/usr/bin/perl
# Michael Tartaglia
# restaurant.cgi
#	This program helps a user decide upon a resaurant to dine in. The user
# enters some options, and the computer "flips coins" and tells the user which
# restaurant to go to


use strict;
use CGI qw( :standard );
require template;

template::startHTML("Freelance Program","Restaurant Chooser");

my $QUERY = $ENV{'QUERY_STRING'};	# QUERY STRING OF USER

# IF THERE WAS NO QUERY STRING (NO INITIAL SUBMISSION), THEN DISPLAY INTRO
print "<p>If you have ever been unable to decide which restaurant in which ",
	"you want to have dinner, this is the program for  you! Enter ",
	"the number of restaurants you are having trouble trying to ",
	"choose between.</p><BR><FORM ACTION=restaurant.cgi>",
	"<input type=text size=3 name=num><input type=submit></FORM>" if ($QUERY eq "");



# IF THERE WAS AN ENTRY MADE, AND IT WAS OF A NUMBER 'N',
#    DISPLAY A FORM THAT CONTAINS N ROWS OF BOXES IN WHICH
#    TO TYPE IN RESTAURANT NAMES
if ($QUERY ne "" && param("num") ne "") {
 my $n = param("num");
 $n =~ s/\D//g;		# ENSURE ONLY A NUMBER WAS ENTERED
 if ($n ne "") {
  print "STEP 2: Now, enter the names of each restaurant.<br>",
	"<FORM ACTION=restaurant.cgi>";
  print "Restaurant #$_: <input type=text size=20 name=\"r$_\"><br>"
	foreach (1 .. $n);
  print "<input type=submit></FORM>";
 }
 elsif ($n < 2) {	# AT LEAST 2 RESTAURANTS NEED BE ENTERED
  print "You need at least two restaurants!<br>",
	"Go back and fix your number." and goto END;
 } 
 else {			# IF NO VALID NUMBER WAS ENTERED
  print "Umm...<br>You gotta enter a number of restaurants.<br>",
	"Go back and fix your number." and goto END;
 }


# ELSE, IF THERE WAS AN ENTRY, AND IT DID NOT CONTAIN A NUMBER
#    GATHER THE RESTAURANT NAMES, "FLIP A COIN," AND DISPLAY
#    RESULTS TO USER
} elsif ($QUERY ne "" && param("num") eq "") {
 my $r = 1;			# INDEX
 my @foodStoreNames = ("");	# NAMES ENTERED IN FORM
 while (param("r$r") ne "") {	# READ IN RESTAURANT NAMES
  $foodStoreNames[$r-1] = param("r$r");
  $r++;
 }

 # IF LESS THAN TWO RESTAURANT NAMES ARE ENTERED
 print "You gotta enter at least two restaurant names!<br>",
	"Go back and fix what you entered."
	and goto END if ($foodStoreNames[0] eq "" || $foodStoreNames[1] eq "");
 my $stores = @foodStoreNames - 1;
 my @foodStoreChoices;		# FOOD STORE CHOICES
    $foodStoreChoices[$_] = 0 foreach (0 .. $stores);
 my $MAX = $stores*100;		# MAXIMUM NUMBER OF COIN FLIPS


 # FLIP COINS
 $foodStoreChoices[rand($stores+1)]++ foreach(1 .. $MAX);

 # AFTER COIN FLIPS, SORT THE FOOD STORES (USING BUBBLE SORTING) INTO
 #    DESCENDING ORDER
 my $swap;
 foreach my $i (0 .. $stores) {
  foreach my $j ($i .. $stores) {
   if ($foodStoreChoices[$j] > $foodStoreChoices[$i]) {
	my $swap = $foodStoreChoices[$i];
	$foodStoreChoices[$i] = $foodStoreChoices[$j];
	$foodStoreChoices[$j] = $swap;
	$swap = $foodStoreNames[$i];
	$foodStoreNames[$i] = $foodStoreNames[$j];
	$foodStoreNames[$j] = $swap;
 }}}


 # DISPLAY RESULTS TO USER
 print "According to what you entered,<br>the program found these ",
	"restaurants most appealing:<br><br><table class=\"noBr\">";
 print "<tr><td>", 1+$_ , ".</td><td>$foodStoreNames[$_]</td><td>(", 
	(int(10000*$foodStoreChoices[$_]/$MAX)/100),
	"\%)</td></tr>" foreach (0 .. $stores);
 print "</table>";
}


END:		# END BLOCK
template::endHTML();