<?php
require("ic_db_connect.php");

function loxodrome($coord1, $coord2) {
	define(R,6371); // km
	$coord1['lat']=deg2rad($coord1['lat']);
	$coord2['lat']=deg2rad($coord2['lat']);
	$coord1['lon']=deg2rad($coord1['lon']);
	$coord2['lon']=deg2rad($coord2['lon']);

	$dLat = ($coord2['lat']-$coord1['lat']);
	$dLon = ($coord2['lon']-($coord1['lon']));
	$dPhi = log(tan($coord2['lat']/2+pi()/4)/tan($coord1['lat']/2+pi()/4));
	$q = (abs($dLat) > 0.0000000001) ? $dLat/$dPhi : cos($coord1['lat']);
	 //if $dLon over 180� take shorter rhumb across 180� meridian:
	if (abs($dLon) > pi()) {
	  $dLon = $dLon>0 ? -1*(2*pi()-$dLon) : (2*pi()+$dLon);
	}
	$dist = sqrt($dLat*$dLat + $q*$q*$dLon*$dLon) * R;
	$dir = fmod(rad2deg(atan2($dPhi,$dLon*-1))+270,360);

	return array($dist,$dir);
}
//$fp = fopen('http://www.aoml.noaa.gov/hrd/hurdat/tracks1851to2008_atl_reanal.html','r') or die ("can't open file");
//$basin="L";
$fp = fopen('http://www.nhc.noaa.gov/tracks1949to2008_epa.txt','r') or die ("can't open file");
$basin="E";
$storm_id=0;
while ($s = fgets($fp,1024)) {
	//some rows doesn't have the 80 characters format (ie. 2008), so we pad them with spaces for unpack to work
    $str_len=strlen($s);
    $s=$str_len<80?str_pad($s,80," "):$s;
if(strlen($s)<80) print($s);
	//parse the header
    if(stripos($s,"SNBR=")) {
    	$fields = unpack('A6SeqNum1/A11StartDate/A2M/A3StormDays/A3StormNum/A5SNBR/A5TotalStormNum/A12StormName/A5XING/A2HitUS/A4SSS/A1HitUSCat/A20Padding/A1LastStorm',$s);

    	$fields_StartDate=explode('/',trim($fields["StartDate"]));
    	$year=$fields_StartDate[2];
		$start_date=$year.$fields_StartDate[0].$fields_StartDate[1];
		$storm_days=trim($fields["StormDays"]);
		$total_storm_num=trim($fields["TotalStormNum"]);
		$storm_num=trim($fields["StormNum"]);
		$storm_name=trim($fields["StormName"]);
		$hit_US=trim($fields["HitUS"]);
		$hit_US_cat=$fields["HitUSCat"];
		$last_storm=$fields["LastStorm"]=='L'?1:0;

		$sql_storm_header="INSERT INTO StormHeader SET start_date='$start_date',storm_days='$storm_days'," .
			"storm_num='$storm_num',total_storm_num='$total_storm_num',storm_name='$storm_name'," .
			"hit_US='$hit_US',hit_US_cat='$hit_US_cat'," .
			"last_storm=$last_storm,basin='$basin' ";
		$res_storm_header=mysql_query($sql_storm_header);

    	$storm_id=mysql_insert_id();
    	$may_be_xyear=false;
    	$lat=0;
    	$lon=0;
    //parse the observations
    } elseif (stripos($s,"/") && !stripos($s,"Z") && $storm_id) {
    	$fields = unpack('A6SeqNum2/A5ObsDate/A1StormType00/A3Lat00/A5Long00/A4WindSpeed00/A4Pressure00/'.
    	'A1StormType06/A3Lat06/A5Long06/A4WindSpeed06/A4Pressure06/'.
    	'A1StormType12/A3Lat12/A5Long12/A4WindSpeed12/A4Pressure12/'.
    	'A1StormType18/A3Lat18/A5Long18/A4WindSpeed18/A4Pressure18/A1Asterisk',$s);

		$fields_ObsDate=explode('/',trim($fields["ObsDate"]));

		$latitude=0;
		$longitude=0;
		$direction=-1;
		$translational_speed=-1;
		$dist_dir=array();
		for($i=0;$i<=18;$i=$i+6) {
			$gmt_time=$gmt=str_pad($i,2,"0",STR_PAD_LEFT);
			$gmt_time=str_pad($gmt_time,6,"0");

			//for crossyear storms, we have to make a special consideration
			$obs_year=$may_be_xyear && $fields_ObsDate[0].$fields_ObsDate[1]!='1231'?$year+1:$year;
			if($fields_ObsDate[0].$fields_ObsDate[1]=='1231') {
				$may_be_xyear=true;
			}
			$obs_date=$obs_year.$fields_ObsDate[0].$fields_ObsDate[1].$gmt_time;
			$storm_type=$fields["StormType$gmt"];
			$latitude=$fields["Lat$gmt"]/10;
			$longitude=trim($fields["Long$gmt"])/10>180?360-trim($fields["Long$gmt"])/10:-1*(trim($fields["Long$gmt"])/10);
			$wind_speed=trim($fields["WindSpeed$gmt"]);
			$central_pressure=trim($fields["Pressure".$gmt]);

			if($latitude) {
				//calculate the current bearing and translational speed (just valid when tracking points > 1)
				if($lat) {
					$dist_dir=loxodrome(array("lat"=>$lat,"lon"=>$lon),array("lat"=>$latitude,"lon"=>$longitude));

					$direction=round($dist_dir[1]);
					$translational_speed=round($dist_dir[0]/(6*1.852));//in knots
				}
				$lat=$latitude;
				$lon=$longitude;
				$coordinate = "PointFromWKB(Point($longitude,$latitude))";

				//all observations from each storm will be inserted as a block, hence the string appending
				$sql_values="('$storm_id','$obs_date','$storm_type','$latitude','$longitude','$wind_speed','$central_pressure','$translational_speed','$direction',$coordinate)";
				$sql_append_values.=$sql_append_values?",$sql_values":"VALUES$sql_values";
			}
		}
		$sql_storm_obs="INSERT INTO StormObservations (storm_id,obs_date,storm_type,latitude,longitude,wind_speed," .
				"central_pressure,translational_speed,direction,coordinate) ".$sql_append_values;
		$res_storm_obs=mysql_query($sql_storm_obs);
		$sql_append_values='';

   	//parse the footer
    } elseif(strlen(trim($s)) && $storm_id) {
		$fields = unpack('A6SeqNum3/A2MaxIntensity/A40LocHitUS/A32Remarks',$s);

		$max_intensity=$fields["MaxIntensity"];
		$remarks=trim($fields["Remarks"]);
		$sql_storm_header_upd="UPDATE StormHeader SET max_intensity='$max_intensity',remarks='$remarks' " .
			"WHERE storm_id=$storm_id";
		$res_storm_header_upd=mysql_query($sql_storm_header_upd);
		$fields_LocHitUS=preg_split( "/(\d)/",$fields["LocHitUS"],-1,PREG_SPLIT_DELIM_CAPTURE);
		$fields_LocHitUS=array_filter($fields_LocHitUS);
		for($i=0;$i<count($fields_LocHitUS);$i=$i+2) {
			if(trim($fields_LocHitUS[$i])) {
				$sql_loc_hit="INSERT INTO StormHeaderLocUS SET storm_id=$storm_id,loc_US='".trim($fields_LocHitUS[$i])."'," .
					"cat_loc_US='{$fields_LocHitUS[$i+1]}'";
				$res_loc_hit=mysql_query($sql_loc_hit);
			}
		}
    }
}
fclose($fp) or die("can't close file");

?>