#!/usr/bin/perl

#
# Grabs the latest local weather conditions from the 
# UF Physics department. Command line option is totally unneeded.
#

$ReportDir  = '.wmWeatherReports';
$WeatherSrc = 'http://www.phys.ufl.edu/~weather/text/mysite.txt';

use strict; 
use vars qw( $ReportDir $WeatherSrc );
use IO::File;

#
#  Change to users home directory. We used to dump into /tmp
#  but using home dir instead avoids multiple users interfering
#  with one another. (Yeah, we could "unique-ize" the filenames, but
#  this is easier for now...)
#
my $home = $ENV{HOME} || (getpwuid($<))[7];
chdir() || chdir($home) or die "chdir '$home' failed: $!";

unless(-e $ReportDir) {
  mkdir $ReportDir, 0755 or die "unable to mkdir '$ReportDir': $!";
}
chdir $ReportDir or die "chdir '$ReportDir' failed: $!";

my $StationID    = "UF";
my $HTMLFileName = "$StationID.TXT";
my $URL          = "$WeatherSrc";
my $DataFileName = "$StationID.dat";

# Is LWP installed?
eval { require LWP::UserAgent };
if ($@) {
  my $cmd = qq{wget --proxy=off --passive-ftp --tries=0 --quiet } .
            qq{--output-document=$home/$ReportDir/$HTMLFileName $URL};
  `$cmd` == 0 or die "unable to fetch weather: $?";
} else {
  $ENV{FTP_PASSIVE} = 1; # LWP uses Net::FTP internally.
  my $ua  = new LWP::UserAgent;
  my $req = new HTTP::Request( GET => $URL );
  my $rsp = $ua->request( $req );
  die $rsp->status_line unless $rsp->is_success;
  my $fh = new IO::File "> $home/$ReportDir/$HTMLFileName" 
    or die "unable to write '$home/$ReportDir/$HTMLFileName': $!";
  print $fh $rsp->content;
  close $fh or die "error closing '$home/$ReportDir/$HTMLFileName': $!";
}

#
# Parse HTML File. 
#

my %stats = (
  temp           => -99.0,
  chill          => -99.0,
  dew_point      => -99.0,
  pressure       => -99.0,
  humidity       => -99.0,
  heat_index     => -99.0,
  rainfall       => -99.0,
  speed         => -99.0,
  dir_word       => 'UP',
  universal_time => '99:99',
);

my $fh = new IO::File $HTMLFileName 
  or die "unable to read '$HTMLFileName': $!";

chomp($stats{station_info} = <$fh>);
chomp($stats{update_date}  = <$fh>);
chomp($stats{update_time}  = <$fh>);

# Grab all the data; go line by line, since I'm not a perl god and I don't know
# how to chomp by two lines while getting the data correctly... uh, yeah.
chomp($stats{null} = <$fh>);
chomp($stats{temp} = <$fh>);
chomp($stats{null} = <$fh>);
chomp($stats{dew_point} = <$fh>);
chomp($stats{null} = <$fh>);
chomp($stats{heat_index} = <$fh>);
chomp($stats{null} = <$fh>);
chomp($stats{chill} = <$fh>);
chomp($stats{null} = <$fh>);
chomp($stats{humidity} = <$fh>);
chomp($stats{null} = <$fh>);
chomp($stats{pressure} = <$fh>);
chomp($stats{null} = <$fh>);
chomp($stats{rainfall} = <$fh>);
chomp($stats{null} = <$fh>);
chomp($stats{dir_word} = <$fh>);
chomp($stats{null} = <$fh>);
chomp($stats{speed} = <$fh>);

if ($stats{temp} =~ /(\-{0,1}[0-9]{1,}).*/) {
    $stats{temp} = $1; }

if ($stats{chill} =~ /(\-{0,1}[0-9]{1,}).*/) {
    $stats{chill} = $1; }

if ($stats{dew_point} =~ /(\-{0,1}[0-9]{1,}).*/) {
    $stats{dew_point} = $1; }

if ($stats{pressure} =~ /(\-{0,1}[0-9]{1,}).*/) {
    $stats{pressure} = $1; }

if ($stats{humidity} =~ /(\-{0,1}[0-9]{1,}).*/) {
    $stats{humidity} = $1; }

if ($stats{dir_word} =~ /(\-{0,1}[0-9]{1,}).*/) {
    $stats{dir_word} = $1; }

if ($stats{speed} =~ /(\d{1,})\%.*/) {
    $stats{speed} = $1; }

close $fh or die "error closing '$HTMLFileName': $!";

$stats{station_info} = "University of Florida Physics Department";
$stats{sky_conditions} = "Rainfall $stats{rainfall}in";

# Determine the wind direction...
# Switch based on N, NW, WNW, W, SW, WSW, S...

for ($stats{dir_word}) {
    if (/NNW\s*/) { $stats{direction} = 337; }
    elsif (/WNW\s*/) { $stats{direction} = 292; }
    elsif (/WSW\s*/) { $stats{direction} = 247; }
    elsif (/SSW\s*/) { $stats{direction} = 202; }
    elsif (/SSE\s*/) { $stats{direction} = 157; }
    elsif (/ESE\s*/) { $stats{direction} = 112; }
    elsif (/ENE\s*/) { $stats{direction} = 67; }
    elsif (/NNE\s*/) { $stats{direction} = 22; }
    elsif (/NW\s*/)  { $stats{direction} = 315; }
    elsif (/SW\s*/)  { $stats{direction} = 225; }
    elsif (/SE\s*/)  { $stats{direction} = 135; }
    elsif (/NE\s*/)  { $stats{direction} = 45; }
    elsif (/N\s*/)   { $stats{direction} = 0;   }  
    elsif (/S\s*/)   { $stats{direction} = 180; }  
    elsif (/E\s*/)   { $stats{direction} = 90; }  
    elsif (/W\s*/)   { $stats{direction} = 270; }  
    else          { $stats{direction} = 1.1; }  # default
}

#
#  Get the Time out of the coded Metar Report.
#
my($hour) = 0;

if ($stats{update_time} =~ /(\d{2}):(\d{2}) ([a-z])/) {
    $hour = $1 + 4; # We're GMT -4 in ET..
# Now, if it's PM, then we need to add 12, and if the 
# result is > 23, then subtract 24! :)
    if ($3 == "pm") { $hour = $hour + 12; }
    if ($hour > 23) { $hour = $hour - 24; }
    if ($hour > 9) { $stats{universal_time} = "$hour:$2"; }
    else { $stats{universal_time} = "0$hour:$2"; }
}

#
#  Write out the stuff we need to the Data File. This is the file that will
#  be read by GKrellWeather.
#
my $fh = new IO::File ">$DataFileName" 
  or die "unable to write '$DataFileName': $!";

print $fh
  map { "$stats{$_}\n" } 
    qw( station_info update_time sky_conditions universal_time
        temp dew_point chill pressure humidity direction speed );

close $fh or die "error closing '$DataFileName': $!";