<?PHP

header('Content-type: text/plain; charset=utf8', true);

function check_header($name, $value = false) {
	if(!isset($_SERVER[$name])) {
		return false;
	}
	if($value && $_SERVER[$name] != $value) {
		return false;
	}
	return true;
}

function sendFile($path) {
	header($_SERVER["SERVER_PROTOCOL"].' 200 OK', true, 200);
	header('Content-Type: application/octet-stream', true);
	header('Content-Disposition: attachment; filename='.basename($path));
	header('Content-Length: '.filesize($path), true);
	header('x-MD5: '.md5_file($path), true);
	readfile($path);
}

if(!check_header('HTTP_USER_AGENT', 'ESP8266-http-Update')) {
	header($_SERVER["SERVER_PROTOCOL"].' 403 Forbidden', true, 403);
	echo "only for ESP8266 updater!\n";
	exit();
}

if(
	!check_header('HTTP_X_ESP8266_STA_MAC') ||
	!check_header('HTTP_X_ESP8266_AP_MAC') ||
	!check_header('HTTP_X_ESP8266_FREE_SPACE') ||
	!check_header('HTTP_X_ESP8266_SKETCH_SIZE') ||
	!check_header('HTTP_X_ESP8266_CHIP_SIZE') ||
	!check_header('HTTP_X_ESP8266_SDK_VERSION') ||
	!check_header('HTTP_X_ESP8266_VERSION')
) {
	header($_SERVER["SERVER_PROTOCOL"].' 403 Forbidden', true, 403);
	echo "only for ESP8266 updater! (header)\n";
	exit();
}

$db = array(
	"18:FE:AA:AA:AA:AA" => "DOOR-7-g14f53a19",
	"18:FE:AA:AA:AA:BB" => "TEMP-1.0.0"
);

if(isset($db[$_SERVER['HTTP_X_ESP8266_STA_MAC']])) {
	if($db[$_SERVER['HTTP_X_ESP8266_STA_MAC']] != $_SERVER['HTTP_X_ESP8266_VERSION']) {
		sendFile("./bin/".$db[$_SERVER['HTTP_X_ESP8266_STA_MAC']]."bin");
	} else {
		header($_SERVER["SERVER_PROTOCOL"].' 304 Not Modified', true, 304);
	}
	exit();
}

header($_SERVER["SERVER_PROTOCOL"].' 500 no version for ESP MAC', true, 500);