#!/usr/bin/perl

use strict;
use LWP::Simple;
use CGI;
#use Geo::METAR;
use Time::Local;

my $NDBC_Data_URL = "http://www.ndbc.noaa.gov/data/realtime2/";

my $w = new CGI;

print $w->header;
print $w->title('West Coast NDBC Summary');
print $w->start_html;
print $w->h2('West Coast NDBC Summary');

print "\n<table border=\"1\" cellspacing=\"0\" cellpadding=\"5\">\n";
print "<tr><td>Site</td><td>Wind (kts)</td><td>Gust (kts)</td><td>Direction</td><td>Wave Ht</td><td>Dominant Pd</td><td>Time (PDT)</td></tr>\n<tr>";
print_ndbc_obs ($NDBC_Data_URL, 46026, "San Francisco");
print "</tr>\n<tr>";
print_ndbc_obs ($NDBC_Data_URL, 46013, "Bodega Bay");
print "</tr>\n<tr>";
print_ndbc_obs ($NDBC_Data_URL, 46014, "Point Arena");
print "</tr>\n<tr>";
print_ndbc_obs ($NDBC_Data_URL, 46022, "Eureka");
print "</tr>\n<tr>";
#print_ndbc_obs ($NDBC_Data_URL, 46027, "Crescent City");
#print "</tr>\n<tr>";
#print_ndbc_obs ($NDBC_Data_URL, 46015, "Port Orford");
#print "</tr>\n<tr>";
print_ndbc_obs ($NDBC_Data_URL, 46229, "Umpqua");
print "</tr>\n<tr>";
print_ndbc_obs ($NDBC_Data_URL, 46050, "Newport");
print "</tr>\n<tr>";
print_ndbc_obs ($NDBC_Data_URL, 46029, "Columbia River");
print "</tr>\n<tr>";
#print_ndbc_obs ($NDBC_Data_URL, 46041, "Aberdeen");
#print "</tr>\n<tr>";
print_ndbc_obs ($NDBC_Data_URL, 46087, "Neah Bay");
print "</tr>\n<tr>";
print "</tr>\n</table>\n";
print "<p>\n";

print $w->end_html;

exit(0);

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

sub print_ndbc_obs
{my $url = shift;
my $site = shift;
my $sitename = shift;

my $eng_url = "http://www.ndbc.noaa.gov/station_page.php\?station=";

my ($obs_time, $obs_wind_dir, $obs_wind_speed, $obs_gust);
my ($obs_wave_ht, $obs_period );

($obs_wind_speed, $obs_wind_dir, $obs_gust, $obs_wave_ht, $obs_period, $obs_time)
               = &get_ndbc_data ($url, $site);
        
#        print "$sitename wind at $obs_time is $obs_speed", "kts ";
#        if ($obs_gust) {print "gusts to $obs_gust", "kts ";}
#        print "from $obs_dir\n";

   print "<td><a href =\"$eng_url$site\">$sitename</a></td><td align=\"center\">$obs_wind_speed</td><td align=\"center\">";
   if ($obs_gust) {print "$obs_gust";}
   else {print "N/A";}
   print "</td><td align=\"center\">$obs_wind_dir</td>";
   print "<td align=\"center\">$obs_wave_ht</td><td align=\"center\">$obs_period</td>";
   print "<td>$obs_time</td>";
}


sub get_ndbc_data
{
my $url = shift;
my $site = shift;
my ($wspeed, $wdir, $gust, $time, $wave_ht, $period);
my ($hour, $min, $meridian, $date, $day, $month, $year);
my $meterstoknots = 1.94384449;
my $meterstofeet = 3.2808399;

$url = $url . $site . ".txt";

my $page = get ($url);

##YY  MM DD hh mm WDIR WSPD GST  WVHT   DPD   APD MWD   PRES  ATMP  WTMP  DEWP  VIS PTDY  TIDE
##yr  mo dy hr mn degT m/s  m/s     m   sec   sec degT   hPa  degC  degC  degC   mi  hPa    ft
#2007 04 28 17 50 300  2.0  3.0   2.6    14    MM  MM 1015.9  10.3  10.3    MM   MM +1.0    MM
#2007 04 28 19 50  MM   MM   MM   3.1    14    MM  MM 1023.9   9.4   7.1    MM   MM   MM    MM

#	       yr	mo       day     hr        min      wdir    wspd   gust    wavht       dom pd   avg etc
$page =~ m#20(\d{2})\s(\d{2})\s(\d{2})\s(\d{2})\s(\d{2})\s+(\S+)\s+(\S+)\s+(\S+)\s+(\d+.\d+)\s+(\d+)\s+MM\s+.*#;

($year, $month, $day, $hour, $min, $wdir, $wspeed, $gust, $wave_ht, $period) = ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10);

#print "url is $url<br>\n";

($month, $day, $year, $hour, $min, $meridian) = &utc_to_local ($month, $day, $year, $hour, $min);

#if ($hour > 12){$meridian = "PM"; $hour = $hour -12;}
#elsif ($hour == 0){$meridian = "AM"; $hour = 12;}
#else {$meridian = "AM";}

if ($wdir eq "MM") {$wdir = "N/A";}

$date = "$month\/$day\/$year";
$time = "$hour:$min $meridian $date";

#Convert to Knots and Round off the wind speeds
   $wspeed = $wspeed * $meterstoknots;
   $gust = $gust * $meterstoknots;

   $wspeed = sprintf ("%.1f", $wspeed);
   $gust = sprintf ("%.1f", $gust);

   $wave_ht =  sprintf ("%.1f", ($wave_ht*$meterstofeet));

if ($wspeed == 0.0) {$wspeed = "N/A";}
if ($gust == 0.0) {$gust = "N/A";}


return ($wspeed, $wdir, $gust, $wave_ht, $period, $time);
}

sub utc_to_local
{my $umon = shift;
my $uday = shift;
my $uyear = shift;
my $uhour = shift;
my $umin = shift;

my ($time, $sec, $min, $hour, $mday, $mon, $year, $wday, $yday, $meridian);
#$time = $w->TIME; #Convert Date and Time from UTC to local
#  $time =~ m/(\d{1,2}):(\d{2}) UTC/;
  ($sec,$min,$hour,$mday,$mon,$year,$wday,$yday) = gmtime(time);
  $min = $umin;
  $hour = $uhour;
  $mday = $uday;
#there could be a wrong day here
  $time = timegm(0,$min,$hour,$mday,$mon,$year,$wday,$yday);
  ($sec,$min,$hour,$mday,$mon,$year,$wday,$yday) = localtime ($time);
  $mon++;
  $year = sprintf ("%02d", ($year - 100)); #Y3K bug... yah yah..
  if ($hour > 12){$hour = $hour - 12; $meridian = "PM";}
  elsif ($hour == 12) {$meridian = "PM";}
  else {$meridian = "AM";}

#$time = "$hour:$min $meridian $mon/$mday/$year";
return ($mon, $mday, $year, $hour, $min, $meridian);
}