<?php
/**
 * Firmware update check
 *
 * Custom firmware versions need a folder in www/firmware/,
 * e.g. www/firmware/0.9.2071/.
 * Each folder needs to contain:
 * - changelog.txt
 * - update.img
 *
 * $GLOBALS['forceFirmwareVersion'] can be set to a custom version
 */
header('HTTP/1.0 500 Internal Server Error');

$rootDir = dirname(__FILE__, 2);
require_once $rootDir . '/config.php';

if (!isset($_POST['v'])) {
    header('HTTP/1.0 400 Bad Request');
    header('Content-Type: text/plain');
    echo "POST data missing\n";
    exit(1);
}

$gsData = json_decode($_POST['v']);
if ($gsData === null) {
    header('HTTP/1.0 400 Bad Request');
    header('Content-Type: text/plain');
    echo "POST data invalid\n";
    exit(1);
}

if (!isset($gsData->hwid)
    || !isset($gsData->major)
    || !isset($gsData->minor)
    || !isset($gsData->revision)
    || !isset($gsData->platform)
) {
    header('HTTP/1.0 400 Bad Request');
    header('Content-Type: text/plain');
    echo "POST data incomplete\n";
    exit(1);
}

$gsVersion = $gsData->major . '.' . $gsData->minor . '.' . $gsData->revision;

$requireUpdate = false;
if (isset($GLOBALS['firmwareVersion'])) {
    $expectedVersion = $GLOBALS['firmwareVersion'];
    if ($gsVersion != $expectedVersion) {
        $requireUpdate = true;
    }
} else {
    $expectedVersion = '0.9.2071';
    if (version_compare($expectedVersion, $gsVersion, '>')) {
        $requireUpdate = true;
    }
}
if (!$requireUpdate) {
    header('HTTP/1.0 200 OK');
    header('Content-type: application/json');
    echo '{"available":false}' . "\n";
    exit(0);
}

list($major, $minor, $revision) = explode('.', $expectedVersion);


$firmwareDir  = $rootDir . '/www/firmware/' . $expectedVersion;
$firmwareFile = $firmwareDir . '/update.img';

if (!file_exists($firmwareFile)) {
    header('HTTP/1.0 200 OK');
    header('Content-type: application/json');
    header('X-Problem: Firmware file missing');
    echo '{"available":false}' . "\n";
    exit(0);
}

$data = [
    'available'   => true,
    'major'       => $major,
    'minor'       => $minor,
    'revision'    => $revision,
    'forced'      => false,
    'name'        => $expectedVersion,
    'description' => file_get_contents($firmwareDir . '/changelog.txt'),
    'timestamp'   => filemtime($firmwareFile),
    'url'         => 'http://update.gamestickservices.net/firmware/download?version=' . $expectedVersion,
];

$json = json_encode($data, JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE);

header('HTTP/1.0 200 OK');
header('Content-Type: application/json');
echo $json . "\n";