#!/usr/bin/perl



use Mysql;
use strict;
use vars qw($school_name);
use vars qw($pass);

require "./cgi-lib.pl";
#do "./school_name.pl";
do "../password.pl";

my (%input, $text, $field);
&ReadParse(\%input);

my @rawCookies = split (/; /,$ENV{'HTTP_COOKIE'});
my %cookies;

foreach(@rawCookies){
    my ($key, $val) = split (/=/,$_);
    $cookies{$key} = $val;
} 

my $id = $input{id};
my $user = $input{user};
my $code = $input{code};
my $course = 0;#$input{course};
my @node;
my @edge;
#my $db_data = Mysql->connect("69.28.179.12", "login", "mark", $pass);
my $db_data = Mysql->connect("$cookies{host}", "$cookies{db}", "mark", $pass);
my $map;
if ($ENV{'HTTP_HOST'} =~ m/^(.*)\.thefacebook\.com/) {
    $map = $1;
}
my $cookie_host = $cookies{host};
my $cookie_db = $cookies{db};
my $sql = "SELECT * FROM school_data where map='$map'";
my $retval = $db_data->query($sql);
my %rs = $retval->fetchhash();
my $host = $rs{ip};
my $dbname = $rs{db};
#my $sql = "INSERT INTO viz (user,map,host,db) VALUES ('$user', '$map','$host', '$dbname')";
#$db_data->query($sql);
my $db = Mysql->connect($host, $dbname, "mark", $pass);
#my $db = Mysql->connect("69.28.179.11", "facebook", "mark", $pass);
my $retval; my $sql;
my %privacy;
my $num_degrees = 1;
my @already_expanded;
my %cs;
     
sub morph {
  my ($number) = @_;
  return ((((($number % 7) * 13) % 17) * 19) % 23);
}

sub share_course {
  my ($user1, $user2) = @_;
  $sql = "SELECT count(*) as count FROM course as course1, course as course2 WHERE " .
    "course1.id = '$user1' AND course2.id = '$user2' AND course1.course_id = course2.course_id";
  $retval = $db->query($sql);
  my %rs = $retval->fetchhash();
  return $rs{count};
}

sub is_one_degree {
  my ($user1, $user2) = @_;
  $sql = "SELECT count(*) as count FROM friend WHERE user1 = '$user1' AND user2 = '$user2'";
  $retval = $db->query($sql);
  my %rs = $retval->fetchhash();
  return $rs{count};
}

sub is_two_degrees {
  #my ($user1, $user2) = @_;
  #$sql = "SELECT count(*) as count FROM friend as f1, friend as f2 " .
  #  "WHERE f1.user1 = '$user1' AND f1.user2 = f2.user1 AND f2.user2 = '$user2'";
  #my %rs = $retval->fetchhash();
  #return $rs{count};
  return 0;
}

sub is_three_degrees {
  #my ($user1, $user2) = @_;
  return 0;
}

sub can_see {
  my ($user, $id, $type) = @_;
  if ($user eq $id) { return 1; }
  $sql = "SELECT house, year, " . $type . "_domain, " . $type . "_type, " .
         $type . "_allow FROM info WHERE info.id = '$id'";
  $retval = $db->query($sql);
  my %control = $retval->fetchhash();
  my $allow = $control{$type . '_allow'};
  my $domain = $control{$type . '_domain'};
  my $privacy_type = $privacy{$type};
  if (($domain eq "" or ($privacy{email} =~ m/$domain$/)) and
      ($control{$type . '_type'} =~ m/-$privacy_type/)) {
    if ($allow =~ m/-1/) {
      $cs{$id} = 1;
      return 1;
    } elsif (($allow =~ m/-2/) and $privacy{year} eq $control{year}) {
      $cs{$id} = 1;
      return 1;
    } elsif (($allow =~ m/-3/) and $privacy{house} eq $control{house}) {
      $cs{$id} = 1;
      return 1;
    } elsif (($allow =~ m/-4/) and share_course($user, $id)) {
      $cs{$id} = 1;
      return 1;
    } elsif (($allow =~ m/-5/) and is_one_degree($user, $id)) {
      $cs{$id} = 1;
      return 1;
    } elsif (($allow =~ m/-6/) and is_two_degrees($user, $id)) {
      $cs{$id} = 1;
      return 1;
    } elsif (($allow =~ m/-7/) and is_three_degrees($user, $id)) {
      $cs{$id} = 1;
      return 1;
    }
  }
  return 0;
}

sub find_node {
  my ($id, $type) = @_;
  for (my $i = 0; $i < @node; $i++) {
    if ($node[$i]{id} eq $id and $node[$i]{type} eq $type) {
      return $i;
    }
  }
  return -1;
}
      
sub find_connections {
  my ($this, $degree, $is_course) = @_;
  my ($type, $type_id);
  if (!$is_course) {
    $already_expanded[@already_expanded] = $this;
    $sql = "SELECT * FROM friend WHERE user1 = '$this' LIMIT 0, 200";
    $type = "friend";
    $type_id = 1;
  } else {
    $sql = "SELECT * FROM course WHERE course_id = '$this'";
    $type = "course";
    $type_id = 0;
  }
  my $return = $db->query($sql);
  while (my %row = $return->fetchhash()) {
    my $new_id;
    if (!$is_course) {
      # get the new id from the friend pair
      #if ($row{user1} eq $this) {
      #  $new_id = $row{user2};
      #} else {
      #  $new_id = $row{user1};
      #}
      $new_id = $row{user2};
    } else {
      $new_id = $row{id};
    }
    if ($degree > $num_degrees or $cs{$new_id} or can_see($user, $new_id, $type)) {
      # see if the id is already a node; if not, add it
      my $node_exists = 0;
      for (my $i = 0; $i < @node and !$node_exists; $i++) {
        if ($node[$i]{id} eq $new_id and $node[$i]{type} eq 1) {
          $node_exists = 1;
        }
      }
      if (!$node_exists and $degree <= $num_degrees) {
        my $next_node = @node;
        $node[$next_node]{id} = $new_id;
        $node[$next_node]{type} = 1;
      }
      # see if there's an edge between the two already; if not, add it
      if ($node_exists or $degree <= $num_degrees) {
        my $edge_exists = 0;
        my $this_index = find_node ($this, $type_id);
        my $new_index = find_node ($new_id, 1);
        for (my $i = 0; $i < @edge and !$edge_exists; $i++) {
          if (($edge[$i][0] eq $this_index and $edge[$i][1] eq $new_index) or
              ($edge[$i][0] eq $new_index and $edge[$i][1] eq $this_index)) {
            $edge_exists = 1;
          }
        }
        if (!$edge_exists) {
          my $next_edge = @edge;
          $edge[$next_edge][0] = $this_index;
          $edge[$next_edge][1] = $new_index;
        }
      }
      # if we want to consider friends farther out, do so now
      if ($degree < $num_degrees + 1) {
        my $expansion_exists = 0;
        for (my $i = 0; $i < @already_expanded and !$expansion_exists; $i++) {
          if ($already_expanded[$i] eq $new_id) {
            $expansion_exists = 1;
          }
        }
        if (!$expansion_exists) {
          if (!$is_course or can_see ($user, $new_id, "friend")) {
            find_connections ($new_id, $degree + 1, 0);
          }
        }
      }
    }
  }
}

sub identify_nodes {
  for (my $i = 0; $i < @node; $i++) {
    if ($node[$i]{type}) {
      $sql = "SELECT name FROM info WHERE id = '" . $node[$i]{id} . "'";
    } else {
      $sql = "SELECT name FROM course_list WHERE id = '" . $node[$i]{id} . "'";
    }
    $retval = $db->query($sql);
    my %row = $retval->fetchhash();
    $node[$i]{name} = $row{name};
  }
}

if ($code == &morph($user) and &can_see($user, $id, "friend")) {  
  # figure out what's going into the graph
  $sql = "SELECT email, house, year FROM info WHERE info.id = '$user'";
  $retval = $db->query($sql);
  %privacy = $retval->fetchhash();
  $node[0]{id} = $id;
  if ($course) {
    $node[0]{type} = 0;
  } else {
    $node[0]{type} = 1;
  }
  find_connections ($id, 1, $course);
  identify_nodes ();
  # generate the graph file
  my $o;
  my $outfile = "/tmp/thefacebook-$id-graph-" . time();
  open  $o, "> $outfile";
  # headers
  print $o "graph g {\n";
  print $o "start=\"yes\"\n";
  print $o "size=\"20,20\"\n";
  print $o "page=\"20,20\"\n";
  print $o "maxiter=1000\n";
  print $o "resolution=100\n";
  print $o "center=true\n";
  print $o "bgcolor=white\n";
  print $o "title=\"A Graph\"\n";
  # nodes                           
  print $o "node [shape=box,fontname=\"Tahoma\",style=filled]\n";
  for (my $i = 0; $i < @node; $i++) {
    my $name = $node[$i]{name};
    $name =~ s/[^A-Z0-9'. ]//gi;
    my ($red, $green, $blue);
    do {
      $red = int(rand() * 201);
      $green = int(rand() * 201);
      $blue = int(rand() * 56) + 200;
    } while ($red + $green + $blue < 400);
    my $extra = "";
    if ($i eq 0) {
      $extra = ",fontsize=32,label=\"$name\"";
    } else {
      $extra = ",fontsize=24,label=\"$name\"";
    }
    printf $o "n$i [color=\"#%02x%02x%02x\"$extra]\n", $red, $green, $blue;
  }
  # edges
  print $o "edge [len=8,color=\"#555555\"]\n";
  for (my $i = 0; $i < @edge; $i++) {
    my $name1 = $node[$edge[$i][0]]{name};
    my $name2 = $node[$edge[$i][1]]{name};
    print $o "n$edge[$i][0] -- n$edge[$i][1] [dir=both,weight=1]\n";
    #print $o "$name1 -- $name2 [dir=both,weight=1]\n";
  }
  # footer
  print $o "}\n\n";
  # compile the graph and output
  my $cmd = "nice neato -Tsvgz $outfile|";
  print "Content-Encoding: gzip\n";
  print "Content-Type: image/svg+xml\n\n";
  #print "Content-Type: text/html\n\n";
  my $file;
  my $pid = open ($file, $cmd);
  while (my $line = <$file>) {
    print $line;
  }
  close $o;
  unlink $outfile;
  #print "what is up..\n";
} else {
  print &PrintHeader;
  print "Authentication failed.  Return <a href='http://";
  print $school_name;
  print ".thefacebook.com/home.php'>home</a>.\n";
}

#print "end...\n";