# poslib.pl
#
#  Poslib Perl interface for Zaza map applet.
#
#  Copyright (C) 2001 Brian Rudy (brudyNO@SPAMpraecogito.com)
#
#  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
#  (at your option) 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.
#
#  
# Requires:
#  Config::IniFiles
#  IPC::ShareLite
#
# Needed by libposlib.so, DISPLAY_LOCALIZE, and posServer
#
## Revision History 
##
# 0.41 8-16-2001
# Fleshed-out new goal semaphore and goal loading. Now operational
# with basic client voting and loading to the planner.
#
# 0.40 8-15-2001
# Added client fingerprinting, goal voting and vote tabulation. 
# Added stubs for new goal semaphores.
#
# 0.30 8-14-2001 
# Basic goal ini reading via Config::IniFiles and storage in shared 
# memory for posServer access.
#
# 0.20 8-13-2001
# Fixed position hash storage and retrieval w/ proper serialization.
# 
# 0.10 8-10-2001
# First working version. Only impliments position retrieval. 
#

use IPC::ShareLite;
use DynaLoader;
use Config::IniFiles;

my $debug = 0;
#my $goalfile = "/home/brudy/posServer/ex_goals.ini";
#my $goalfile = "/home/brudy/posServer/in_goals.ini";
my $goalfile = "/home/brudy/posServer/mccabe_goals.ini";



use Storable qw(freeze thaw);

# These default to 65,536 bytes each, so use the default
# with care.
my $posshare = new IPC::ShareLite( -key => 1492,
                             -create  => 'yes',
                             -destroy => 'no',
                             -size    => 200 ) or die $!;

my $goalshare = new IPC::ShareLite( -key => 1493,
                             -create  => 'yes',
                             -destroy => 'no', 
                             -size    => 5000 ) or die $!;

my $voteshare = new IPC::ShareLite( -key => 1494,
                             -create  => 'yes',
                             -destroy => 'no' ) or die $!;

my $semaphoreshare = new IPC::ShareLite( -key => 1495,
                             -create  => 'yes',
                             -destroy => 'no',
                             -size    => 8  ) or die $!;

sub poslibinit {
  # not 0, helps client debugging
  pushpos(1, 1, 1);
  flushsemaphores();
  flushvotes();
  read_goal_file();
}

sub pushpos {
  ($x, $y, $theta) = @_ ;

  if ($debug) {
    print "got x=" . $x . " ,y=" . $y . ", and theta=" . $theta . "\n";
  }
 
  %Position = ('x' => $x, 'y' => $y, 'theta' => $theta); 
  $posshare->store(freeze(\%Position));

  if ($debug) {
    ## This is for verification only
    my %retpos = %{thaw($posshare->fetch)};
    my $nx = %retpos->{'x'};
    my $ny = %retpos->{'y'};
    my $ntheta = %retpos->{'theta'};
    print "now x=" . $nx . " , y=" . $ny . ", and theta=" . $ntheta ."\n";
  } 
  # this is totally arbitrary right now
  return $x + $y; 
}


sub poppos {
   my %fretpos = %{thaw($posshare->fetch)};   
#  print "Current position is x=" . %fretpos->{'x'} . ", y=" . %fretpos->{'y'} . ", theta=" . %fretpos->{'theta'} . "\n";  
  %fretpos->{'x'}, %fretpos->{'y'}, %fretpos->{'theta'};
}


sub read_goal_file {
  my $goalini = new Config::IniFiles( -file => $goalfile );

  # load it all into an Array of Hashes
  
  my @GoalAoH;
  for (my $i = 0; $i <= 19; $i++) {
   if ($goalini->val( $i, 'Enabled' ) eq 'yes') {
     $GoalAoH[$i]{Name}    = $goalini->val( $i, 'Name' );
     $GoalAoH[$i]{URL}     = $goalini->val( $i, 'URL' );
     $GoalAoH[$i]{Appletx} = $goalini->val( $i, 'Appletx' );
     $GoalAoH[$i]{Applety} = $goalini->val( $i, 'Applety' );
     $GoalAoH[$i]{Realx}   = $goalini->val( $i, 'Realx' );
     $GoalAoH[$i]{Realy}   = $goalini->val( $i, 'Realy' );
     $GoalAoH[$i]{Enabled} = $goalini->val( $i, 'Enabled' );
     $GoalAoH[$i]{Votes}   = 0;
     #print "\$i=" . $i . " is enabled\n";
   }
   #else {
   #  print "\$i=" . $i . " is disabled\n";
   #}
  }
  
  # Then read it all out again
  #for $index (0 .. $#GoalAoH) {
  #  print "[" . $index . "]\n";
  #  print "Name="    . $GoalAoH[$index]{Name} . "\n";
  #  print "URL="     . $GoalAoH[$index]{URL} . "\n";
  #  print "Appletx=" . $GoalAoH[$index]{Appletx} . "\n";
  #  print "Applety=" . $GoalAoH[$index]{Applety} . "\n";
  #  print "Realx="   . $GoalAoH[$index]{Realx} . "\n";
  #  print "Realy="   . $GoalAoH[$index]{Realy} . "\n";
  #  print "Enabled="   . $GoalAoH[$index]{Enabled} . "\n";
  #  print "Votes="   . $GoalAoH[$index]{Votes} . "\n";
  #}
 
  my $frozengoals = freeze(\@GoalAoH);
  #print "\n\$frozengoals is " . length($frozengoals) . " bytes.\n";
  #print "Storing in shared memory...\n"; 
  $goalshare->store($frozengoals);

  #print "...and now retrieving\n";
  #my @newgoalsAoH = @{thaw($goalshare->fetch)};
  #
  #for $j (0 .. $#newgoalsAoH) {
  # print "$j is { ";
  # for $role (keys %{ $newgoalsAoH[$j] }) {
  #   print "$role= $newgoalsAoH[$j]{$role}\n";
  # }
  # print "}\n";
  #}
}



# pop the goals AoH out of shared memory
sub popgoals {
  @{thaw($goalshare->fetch)};
}



# register vote for goal
sub votegoal {
  ($goalnum, $clientip) = @_ ;

  #my $binip = IpToBin($clientip);

  ## Kludgy Client Fingerprinting Schema (TM) ;)

  # %votelist is a hash of arrays, with the key as the 
  # client's IP address and the array element as the goal
  # number.
  my %votelist = %{thaw($voteshare->fetch)};
  if ($votelist{$clientip}[$goalnum] == 1) {
    print "no\n";
    print "I already have a vote from you for that goal.\n";
  } 
  else {
    $votelist{$clientip}[$goalnum] = 1;
    print "ok\n";
    print "Vote accepted.\n";
    $voteshare->store(freeze(\%votelist));
    # This is for testing only!
    $semaphoreshare->store("1");
  }

  #print "The unmodified string is " . length($clientip) . 
  # " and the binary version is " . length($binip) . " which is " . 
  # $binip . ".\n";
  #print "Hey " . $clientip . " I got your goal " . $goalnum . 
  # " right here...\n";
}


# Tally all votes
sub tallyvotes {
  my %votelist = %{thaw($voteshare->fetch)};
  my @mrgoals = popgoals();
  my $votestotal = 0;
  my %votetally;
  for $client (keys %votelist) {
    for $i (0 .. $#{ $votelist{$client} }) {
      if ($votelist{$client}[$i] == 1) {
        $votetally{$i}++;
      }
    }
  }  
  # how many have we got?
  for $j (keys %votetally) {
    print $votetally{$j} . " votes for " . $mrgoals[$j]{Name} . ".\n";
    $votestotal += $votetally{$j};
  }
  if (($votestotal != 0) && ((keys %votetally) != 0)) {
    my $votesaverage = sprintf("%.0f", $votestotal/(keys %votetally));
    print "The total number of votes is " . $votestotal . 
     ". The average number is " . $votesaverage . "\n";
  }
  else {
    print "There are no votes!\n";
  }
}


# Print current vote tabulation (for debugging)
sub printvotes {
  my @mrgoals = popgoals();
  my %votelist = %{thaw($voteshare->fetch)};
  for $client (keys %votelist) {
    print $client . "\n";
    for $i (0 .. $#{ $votelist{$client} }) {
      if ($votelist{$client}[$i] == 1) {
        print "--" . $mrgoals[$i]{Name} . "\n";
      }
    }
    print "\n";
  }
}


# Return the first voted goal found
# This function is for testing only
sub getgoal {
  my @mrgoals = popgoals();
  my %votelist = %{thaw($voteshare->fetch)};
  for $client (keys %votelist) {
    for $i (0 .. $#{ $votelist{$client} }) {
      if ($votelist{$client}[$i] == 1) {
        return($mrgoals[$i]{Realx}, $mrgoals[$i]{Realy});
      }
    }
  }
}


# Flush out semaphore shared memory
sub flushsemaphores {
  $semaphoreshare->store("0");
}


# Flush out vote shared memory space
sub flushvotes {
  my %votelist;
  $votelist{'127.0.0.1'}[0] = 0;
  $voteshare->store(freeze(\%votelist));
}


# Check if a new goal has been added
sub newgoal {
  my $check = $semaphoreshare->fetch;
  if ($check eq '1') {
    return 1;
  }
  else {
    return 0;
  }
}



#
# Components of the following sub have been borrowed from Charles
# Kereke's IpMath.pl (http://homepages.waymark.net/~ckerekes/IpMath.pl)
#

#This sub converts an entire ip address or subnet mask to char
sub IpToBin {

	my ($ip) = @_[0];  #this is the ip to convert
	my @octets, $bin;
	
	#Split up octets into the array
	@octets=split(/\./,$ip);

	#Append the decimal value of the octets	
	$bin = unpack("c", $octets[0]);
	$bin .= unpack("c", $octets[1]);
	$bin .= unpack("c", $octets[2]);
	$bin .= unpack("c", $octets[3]);

	#return the result in $bin
	$bin;
}





1;