<?php
header('Content-Type: application/json');

// URL for the NHC active hurricane KML data
$nhc_kmz_url = 'https://www.nhc.noaa.gov/gis/kml/nhc.kmz';

// Temporary file to store the KMZ
$tmp_kmz_file = tempnam(sys_get_temp_dir(), 'nhc_kmz');

// Fetch the KMZ file
$kmz_data = file_get_contents($nhc_kmz_url);

if ($kmz_data === false) {
    echo json_encode(['error' => 'Failed to fetch NHC data.']);
    exit;
}

// Save the data to the temporary file
file_put_contents($tmp_kmz_file, $kmz_data);

if (!class_exists('ZipArchive')) {
    echo json_encode(['error' => 'ZipArchive class does not exist.']);
    exit;
}

// Use ZipArchive to open the KMZ file
$zip = new ZipArchive;
if ($zip->open($tmp_kmz_file) === TRUE) {
    // NHC KMZ files typically contain a single KML file, often named doc.kml or similar.
    // We will look for the first .kml file in the archive.
    $kml_content = false;
    for ($i = 0; $i < $zip->numFiles; $i++) {
        $filename = $zip->getNameIndex($i);
        if (strtolower(substr($filename, -4)) === '.kml') {
            $kml_content = $zip->getFromIndex($i);
            break;
        }
    }
    $zip->close();

    if ($kml_content === false) {
        echo json_encode(['error' => 'KML file not found in the KMZ archive.']);
        exit;
    }

    // Parse the KML content
    $xml = simplexml_load_string($kml_content, "SimpleXMLElement", LIBXML_NOCDATA);
    if ($xml === false) {
        echo json_encode(['error' => 'Failed to parse KML data.']);
        exit;
    }

    // Register the KML namespace
    $xml->registerXPathNamespace('kml', 'http://www.opengis.net/kml/2.2');

    $features = [];

    // Find all Placemarks in the KML
    foreach ($xml->xpath('//kml:Placemark') as $placemark) {
        $placemark->registerXPathNamespace('kml', 'http://www.opengis.net/kml/2.2');
        $name = (string)$placemark->name;
        
        // Look for Polygon
        $polygon = $placemark->xpath('.//kml:Polygon');
        if ($polygon && isset($polygon[0]->outerBoundaryIs->LinearRing->coordinates)) {
            $coordinates_str = (string)$polygon[0]->outerBoundaryIs->LinearRing->coordinates;
            $coordinates = parse_coordinates($coordinates_str);
            if (!empty($coordinates)) {
                $features[] = [
                    'name' => $name,
                    'type' => 'Polygon',
                    'coordinates' => $coordinates
                ];
            }
        }

        // Look for LineString
        $linestring = $placemark->xpath('.//kml:LineString');
        if ($linestring && isset($linestring[0]->coordinates)) {
            $coordinates_str = (string)$linestring[0]->coordinates;
            $coordinates = parse_coordinates($coordinates_str);
            if (!empty($coordinates)) {
                $features[] = [
                    'name' => $name,
                    'type' => 'LineString',
                    'coordinates' => $coordinates
                ];
            }
        }
    }

    echo json_encode($features);

} else {
    echo json_encode(['error' => 'Failed to open KMZ file.']);
}

// Clean up the temporary file
unlink($tmp_kmz_file);

function parse_coordinates($coordinates_str) {
    $coords = [];
    $pairs = explode(' ', trim($coordinates_str));
    foreach ($pairs as $pair) {
        $parts = explode(',', $pair);
        if (count($parts) >= 2) {
            $lon = floatval($parts[0]);
            $lat = floatval($parts[1]);
            // Ensure coordinates are valid
            if (is_finite($lat) && is_finite($lon)) {
                $coords[] = $lon;
                $coords[] = $lat;
            }
        }
    }
    return $coords;
}
?>