6 files changed, 717 insertions, 75 deletions

diff --git a/lib/Slic3r/GUI/MainFrame.pm b/lib/Slic3r/GUI/MainFrame.pm
index 034cc2dd5..ee5ec7cb5 100644
--- a/lib/Slic3r/GUI/MainFrame.pm
+++ b/lib/Slic3r/GUI/MainFrame.pm
@@ -413,8 +413,7 @@ sub _init_menubar {
     my $hokusMenu = Wx::Menu->new;    # XXX: tmp
     {
         $self->_append_menu_item($hokusMenu, "Pokus", "Pokus", sub {
-            # Slic3r::Http::download();
-            Slic3r::OctoPrint::send_gcode("10.0.0.46", "70E4CFD0E0D7423CB6B1CF055DBAEFA5", "/home/vojta/prog/tisk/jesterka/jesterka.gcode");
+            Slic3r::Http::pokus();
         });
     }
 
diff --git a/xs/CMakeLists.txt b/xs/CMakeLists.txt
index b73f8336d..d8ef51caa 100644
--- a/xs/CMakeLists.txt
+++ b/xs/CMakeLists.txt
@@ -203,6 +203,8 @@ add_library(libslic3r_gui STATIC
     ${LIBDIR}/slic3r/Utils/Http.hpp
     ${LIBDIR}/slic3r/Utils/OctoPrint.cpp
     ${LIBDIR}/slic3r/Utils/OctoPrint.hpp
+    ${LIBDIR}/slic3r/Utils/Bonjour.cpp
+    ${LIBDIR}/slic3r/Utils/Bonjour.hpp
 )
 
 add_library(admesh STATIC
diff --git a/xs/src/slic3r/Utils/Bonjour.cpp b/xs/src/slic3r/Utils/Bonjour.cpp
new file mode 100644
index 000000000..d7fb30e64
--- /dev/null
+++ b/xs/src/slic3r/Utils/Bonjour.cpp
@@ -0,0 +1,602 @@
+#include "Bonjour.hpp"
+
+#include <cstdint>
+#include <algorithm>
+#include <unordered_map>
+#include <array>
+#include <vector>
+#include <string>
+#include <random>
+#include <thread>
+#include <boost/optional.hpp>
+#include <boost/system/error_code.hpp>
+#include <boost/endian/conversion.hpp>
+#include <boost/asio.hpp>
+#include <boost/date_time/posix_time/posix_time_duration.hpp>
+#include <boost/format.hpp>
+
+using boost::optional;
+using boost::system::error_code;
+namespace endian = boost::endian;
+namespace asio = boost::asio;
+using boost::asio::ip::udp;
+
+
+// TODO: Fuzzing test
+
+namespace Slic3r {
+
+
+// Miniman implementation of a MDNS client
+// This implementation is extremely simple, only the bits that are useful
+// for very basic MDNS discovery are present.
+
+struct DnsName: public std::string
+{
+	enum
+	{
+		MAX_RECURSION = 10,     // Keep this low
+	};
+
+	static optional<DnsName> decode(const std::vector<char> &buffer, ptrdiff_t &offset, unsigned depth = 0)
+	{
+		// We trust that the offset passed is bounds-checked properly,
+		// including that there is at least one byte beyond that offset.
+		// Any further arithmetic has to be bounds-checked here though.
+
+		// Check for recursion depth to prevent parsing names that are nested too deeply
+		// or end up cyclic:
+		if (depth >= MAX_RECURSION) {
+			return boost::none;
+		}
+
+		DnsName res;
+		const ptrdiff_t bsize = buffer.size();
+
+		while (true) {
+			const char* ptr = buffer.data() + offset;
+			char len = *ptr;
+			if (len & 0xc0) {
+				// This is a recursive label
+				ptrdiff_t pointer = (len & 0x3f) << 8 | ptr[1];
+				const auto nested = decode(buffer, pointer, depth + 1);
+				if (!nested) {
+					return boost::none;
+				} else {
+					if (res.size() > 0) {
+						res.push_back('.');
+					}
+					res.append(*nested);
+					offset += 2;
+					return std::move(res);
+				}
+			} else if (len == 0) {
+				// This is a name terminator
+				offset++;
+				break;
+			} else {
+				// This is a regular label
+				len &= 0x3f;
+				if (len + offset + 1 >= bsize) {
+					return boost::none;
+				}
+
+				res.reserve(len);
+				if (res.size() > 0) {
+					res.push_back('.');
+				}
+
+				ptr++;
+				for (const auto end = ptr + len; ptr < end; ptr++) {
+					char c = *ptr;
+					if (c >= 0x20 && c <= 0x7f) {
+						res.push_back(c);
+					} else {
+						return boost::none;
+					}
+				}
+
+				offset += len + 1;
+			}
+		}
+
+		if (res.size() > 0) {
+			return std::move(res);
+		} else {
+			return boost::none;
+		}
+	}
+};
+
+struct DnsHeader
+{
+	uint16_t id;
+	uint16_t flags;
+	uint16_t qdcount;
+	uint16_t ancount;
+	uint16_t nscount;
+	uint16_t arcount;
+
+	enum
+	{
+		SIZE = 12,
+	};
+
+	static DnsHeader decode(const std::vector<char> &buffer) {
+		DnsHeader res;
+		const uint16_t *data_16 = reinterpret_cast<const uint16_t*>(buffer.data());
+		res.id = endian::big_to_native(data_16[0]);
+		res.flags = endian::big_to_native(data_16[1]);
+		res.qdcount = endian::big_to_native(data_16[2]);
+		res.ancount = endian::big_to_native(data_16[3]);
+		res.nscount = endian::big_to_native(data_16[4]);
+		res.arcount = endian::big_to_native(data_16[5]);
+		return res;
+	}
+
+	uint32_t rrcount() const {
+		return ancount + nscount + arcount;
+	}
+};
+
+struct DnsQuestion
+{
+	enum
+	{
+		MIN_SIZE = 5,
+	};
+
+	DnsName name;
+	uint16_t type;
+	uint16_t qclass;
+
+	DnsQuestion() :
+		type(0),
+		qclass(0)
+	{}
+
+	static optional<DnsQuestion> decode(const std::vector<char> &buffer, ptrdiff_t &offset)
+	{
+		auto qname = DnsName::decode(buffer, offset);
+		if (!qname) {
+			return boost::none;
+		}
+
+		DnsQuestion res;
+		res.name = std::move(*qname);
+		const uint16_t *data_16 = reinterpret_cast<const uint16_t*>(buffer.data() + offset);
+		res.type = endian::big_to_native(data_16[0]);
+		res.qclass = endian::big_to_native(data_16[1]);
+
+		offset += 4;
+		return std::move(res);
+	}
+};
+
+struct DnsResource
+{
+	DnsName name;
+	uint16_t type;
+	uint16_t rclass;
+	uint32_t ttl;
+	std::vector<char> data;
+
+	DnsResource() :
+		type(0),
+		rclass(0),
+		ttl(0)
+	{}
+
+	static optional<DnsResource> decode(const std::vector<char> &buffer, ptrdiff_t &offset, ptrdiff_t &dataoffset)
+	{
+		auto rname = DnsName::decode(buffer, offset);
+		if (!rname) {
+			return boost::none;
+		}
+
+		const ptrdiff_t bsize = buffer.size();
+
+		if (offset + 10 >= bsize) {
+			return boost::none;
+		}
+
+		DnsResource res;
+		res.name = std::move(*rname);
+		const uint16_t *data_16 = reinterpret_cast<const uint16_t*>(buffer.data() + offset);
+		res.type = endian::big_to_native(data_16[0]);
+		res.rclass = endian::big_to_native(data_16[1]);
+		res.ttl = endian::big_to_native(*reinterpret_cast<const uint32_t*>(data_16 + 2));
+		uint16_t rdlength = endian::big_to_native(data_16[4]);
+
+		offset += 10;
+		if (offset + rdlength > bsize) {
+			return boost::none;
+		}
+
+		dataoffset = offset;
+		res.data = std::move(std::vector<char>(buffer.begin() + offset, buffer.begin() + offset + rdlength));
+		offset += rdlength;
+
+		return std::move(res);
+	}
+};
+
+struct DnsRR_A
+{
+	enum { TAG = 0x1 };
+
+	asio::ip::address_v4 ip;
+
+	static void decode(optional<DnsRR_A> &result, const DnsResource &rr)
+	{
+		if (rr.data.size() == 4) {
+			DnsRR_A res;
+			const uint32_t ip = endian::big_to_native(*reinterpret_cast<const uint32_t*>(rr.data.data()));
+			res.ip = asio::ip::address_v4(ip);
+			result = std::move(res);
+		}
+	}
+};
+
+struct DnsRR_AAAA
+{
+	enum { TAG = 0x1c };
+
+	asio::ip::address_v6 ip;
+
+	static void decode(optional<DnsRR_AAAA> &result, const DnsResource &rr)
+	{
+		if (rr.data.size() == 16) {
+			DnsRR_AAAA res;
+			std::array<unsigned char, 16> ip;
+			std::copy_n(rr.data.begin(), 16, ip.begin());
+			res.ip = asio::ip::address_v6(ip);
+			result = std::move(res);
+		}
+	}
+};
+
+struct DnsRR_SRV
+{
+	enum
+	{
+		TAG = 0x21,
+		MIN_SIZE = 8,
+	};
+
+	uint16_t priority;
+	uint16_t weight;
+	uint16_t port;
+	std::string name;
+	std::string service;
+	DnsName hostname;
+
+	static void decode(std::vector<DnsRR_SRV> &results, const std::vector<char> &buffer, const DnsResource &rr, ptrdiff_t dataoffset)
+	{
+		if (rr.data.size() < MIN_SIZE) {
+			return;
+		}
+
+		DnsRR_SRV res;
+
+		{
+			const auto dot_pos = rr.name.find_first_of('.');
+			if (dot_pos > 0 && dot_pos < rr.name.size() - 1) {
+				res.name = rr.name.substr(0, dot_pos);
+				res.service = rr.name.substr(dot_pos + 1);
+			} else {
+				return;
+			}
+		}
+
+		const uint16_t *data_16 = reinterpret_cast<const uint16_t*>(rr.data.data());
+		res.priority = endian::big_to_native(data_16[0]);
+		res.weight = endian::big_to_native(data_16[1]);
+		res.port = endian::big_to_native(data_16[2]);
+
+		ptrdiff_t offset = dataoffset + 6;
+		auto hostname = DnsName::decode(buffer, offset);
+
+		if (hostname) {
+			res.hostname = std::move(*hostname);
+			results.emplace_back(std::move(res));
+		}
+	}
+};
+
+struct DnsMessage
+{
+	enum
+	{
+		MAX_SIZE = 4096,
+		MAX_ANS = 30,
+	};
+
+	DnsHeader header;
+	optional<DnsQuestion> question;
+	std::vector<DnsResource> answers;
+
+	optional<DnsRR_A> rr_a;
+	optional<DnsRR_AAAA> rr_aaaa;
+	std::vector<DnsRR_SRV> rr_srv;
+
+	static optional<DnsMessage> decode(const std::vector<char> &buffer, optional<uint16_t> id_wanted = boost::none)
+	{
+		const auto size = buffer.size();
+		if (size < DnsHeader::SIZE + DnsQuestion::MIN_SIZE || size > MAX_SIZE) {
+			return boost::none;
+		}
+
+		DnsMessage res;
+		res.header = DnsHeader::decode(buffer);
+
+		if (id_wanted && *id_wanted != res.header.id) {
+			return boost::none;
+		}
+
+		if (res.header.qdcount > 1 || res.header.ancount > MAX_ANS) {
+			return boost::none;
+		}
+
+		ptrdiff_t offset = DnsHeader::SIZE;
+		if (res.header.qdcount == 1) {
+			res.question = DnsQuestion::decode(buffer, offset);
+		}
+
+		for (unsigned i = 0; i < res.header.rrcount(); i++) {
+			ptrdiff_t dataoffset = 0;
+			auto rr = DnsResource::decode(buffer, offset, dataoffset);
+			if (!rr) {
+				return boost::none;
+			} else {
+				res.parse_rr(buffer, *rr, dataoffset);
+				res.answers.push_back(std::move(*rr));
+			}
+		}
+
+		return std::move(res);
+	}
+private:
+	void parse_rr(const std::vector<char> &buffer, const DnsResource &rr, ptrdiff_t dataoffset)
+	{
+		switch (rr.type) {
+			case DnsRR_A::TAG: DnsRR_A::decode(this->rr_a, rr); break;
+			case DnsRR_AAAA::TAG: DnsRR_AAAA::decode(this->rr_aaaa, rr); break;
+			case DnsRR_SRV::TAG: DnsRR_SRV::decode(this->rr_srv, buffer, rr, dataoffset); break;
+		}
+	}
+};
+
+
+struct BonjourRequest
+{
+	static const asio::ip::address_v4 MCAST_IP4;
+	static const uint16_t MCAST_PORT;
+
+	static const char rq_template[];
+
+	uint16_t id;
+	std::vector<char> data;
+
+	static optional<BonjourRequest> make(const std::string &service, const std::string &protocol);
+
+private:
+	BonjourRequest(uint16_t id, std::vector<char> &&data) :
+		id(id),
+		data(std::move(data))
+	{}
+};
+
+const asio::ip::address_v4 BonjourRequest::MCAST_IP4{0xe00000fb};
+const uint16_t BonjourRequest::MCAST_PORT = 5353;
+
+const char BonjourRequest::rq_template[] = {
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x05, 0x5f, 0x68, 0x74,
+	0x74, 0x70, 0x04, 0x5f, 0x74, 0x63, 0x70, 0x05, 0x6c, 0x6f, 0x63, 0x61, 0x6c, 0x00, 0x00, 0x0c,
+	0x00, 0x01,
+};
+
+optional<BonjourRequest> BonjourRequest::make(const std::string &service, const std::string &protocol)
+{
+	if (service.size() > 15 || protocol.size() > 15) {
+		return boost::none;
+	}
+
+	std::random_device dev;
+	std::uniform_int_distribution<uint16_t> dist;
+	uint16_t id = dist(dev);
+	uint16_t id_big = endian::native_to_big(id);
+	const char *id_char = reinterpret_cast<char*>(&id_big);
+
+	std::vector<char> data;
+	data.reserve(service.size() + 18);
+
+	// Add the transaction ID
+	data.push_back(id_char[0]);
+	data.push_back(id_char[1]);
+
+	// Add metadata
+	static const char rq_meta[] = {
+		0x00, 0x00, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
+	};
+	std::copy(rq_meta, rq_meta + sizeof(rq_meta), std::back_inserter(data));
+
+	// Add PTR query name
+	data.push_back(service.size() + 1);
+	data.push_back('_');
+	data.insert(data.end(), service.begin(), service.end());
+	data.push_back(protocol.size() + 1);
+	data.push_back('_');
+	data.insert(data.end(), protocol.begin(), protocol.end());
+
+	// Add the rest of PTR record
+	static const char ptr_tail[] = {
+		0x05, 0x6c, 0x6f, 0x63, 0x61, 0x6c, 0x00, 0x00, 0x0c, 0x00, 0x01,
+	};
+	std::copy(ptr_tail, ptr_tail + sizeof(ptr_tail), std::back_inserter(data));
+
+	return BonjourRequest(id, std::move(data));
+}
+
+
+// API - private part
+
+struct Bonjour::priv
+{
+	const std::string service;
+	const std::string protocol;
+	const std::string service_dn;
+	unsigned timeout;
+	uint16_t rq_id;
+
+	std::vector<char> buffer;
+	std::thread io_thread;
+	Bonjour::ReplyFn replyfn;
+	Bonjour::CompleteFn completefn;
+
+	priv(std::string service, std::string protocol);
+
+	void udp_receive(const error_code &error, size_t bytes);
+	void lookup_perform();
+};
+
+Bonjour::priv::priv(std::string service, std::string protocol) :
+	service(std::move(service)),
+	protocol(std::move(protocol)),
+	service_dn((boost::format("_%1%._%2%.local") % this->service % this->protocol).str()),
+	timeout(10),
+	rq_id(0)
+{
+	buffer.resize(DnsMessage::MAX_SIZE);
+}
+
+void Bonjour::priv::udp_receive(const error_code &error, size_t bytes)
+{
+	if (error || bytes == 0 || !replyfn) {
+		return;
+	}
+
+	buffer.resize(bytes);
+	const auto dns_msg = DnsMessage::decode(buffer, rq_id);
+	if (dns_msg) {
+		std::string ip;
+		if (dns_msg->rr_a) { ip = dns_msg->rr_a->ip.to_string(); }
+		else if (dns_msg->rr_aaaa) { ip = dns_msg->rr_aaaa->ip.to_string(); }
+
+		for (const auto &srv : dns_msg->rr_srv) {
+			if (srv.service == service_dn) {
+				replyfn(std::move(ip), std::move(srv.hostname), std::move(srv.name));
+			}
+		}
+	}
+}
+
+void Bonjour::priv::lookup_perform()
+{
+	const auto brq = BonjourRequest::make(service, protocol);
+	if (!brq) {
+		return;
+	}
+
+	auto self = this;
+	rq_id = brq->id;
+
+	try {
+		boost::asio::io_service io_service;
+		udp::socket socket(io_service);
+		socket.open(udp::v4());
+		socket.set_option(udp::socket::reuse_address(true));
+		udp::endpoint mcast(BonjourRequest::MCAST_IP4, BonjourRequest::MCAST_PORT);
+		socket.send_to(asio::buffer(brq->data), mcast);
+
+		bool timeout = false;
+		asio::deadline_timer timer(io_service);
+		timer.expires_from_now(boost::posix_time::seconds(10));
+		timer.async_wait([=, &timeout](const error_code &error) {
+			timeout = true;
+			if (self->completefn) {
+				self->completefn();
+			}
+		});
+
+		const auto recv_handler = [=](const error_code &error, size_t bytes) {
+			self->udp_receive(error, bytes);
+		};
+		socket.async_receive(asio::buffer(buffer, buffer.size()), recv_handler);
+
+		while (io_service.run_one()) {
+			if (timeout) {
+				socket.cancel();
+			} else {
+				buffer.resize(DnsMessage::MAX_SIZE);
+				socket.async_receive(asio::buffer(buffer, buffer.size()), recv_handler);
+			}
+		}
+	} catch (std::exception& e) {
+	}
+}
+
+
+// API - public part
+
+Bonjour::Bonjour(std::string service, std::string protocol) :
+	p(new priv(std::move(service), std::move(protocol)))
+{}
+
+Bonjour::Bonjour(Bonjour &&other) : p(std::move(other.p)) {}
+
+Bonjour::~Bonjour()
+{
+	if (p && p->io_thread.joinable()) {
+		p->io_thread.detach();
+	}
+}
+
+Bonjour& Bonjour::set_timeout(unsigned timeout)
+{
+	if (p) { p->timeout = timeout; }
+	return *this;
+}
+
+Bonjour& Bonjour::on_reply(ReplyFn fn)
+{
+	if (p) { p->replyfn = std::move(fn); }
+	return *this;
+}
+
+Bonjour& Bonjour::on_complete(CompleteFn fn)
+{
+	if (p) { p->completefn = std::move(fn); }
+	return *this;
+}
+
+Bonjour::Ptr Bonjour::lookup()
+{
+	auto self = std::make_shared<Bonjour>(std::move(*this));
+
+	if (self->p) {
+		auto io_thread = std::thread([self](){
+				self->p->lookup_perform();
+			});
+		self->p->io_thread = std::move(io_thread);
+	}
+
+	return self;
+}
+
+
+void Bonjour::pokus()   // XXX
+{
+	// auto bonjour = Bonjour("http")
+	//     .set_timeout(15)
+	//     .on_reply([](std::string ip, std::string host, std::string service_name) {
+	//         std::cerr << "MDNS: " << ip << " = " << host << " : " << service_name << std::endl;
+	//     })
+	//     .on_complete([](){
+	//         std::cerr << "MDNS lookup complete" << std::endl;
+	//     })
+	//     .lookup();
+}
+
+
+}
diff --git a/xs/src/slic3r/Utils/Bonjour.hpp b/xs/src/slic3r/Utils/Bonjour.hpp
new file mode 100644
index 000000000..039db3370
--- /dev/null
+++ b/xs/src/slic3r/Utils/Bonjour.hpp
@@ -0,0 +1,39 @@
+#ifndef slic3r_Bonjour_hpp_
+#define slic3r_Bonjour_hpp_
+
+#include <memory>
+#include <string>
+#include <functional>
+
+
+namespace Slic3r {
+
+
+/// Bonjour lookup
+class Bonjour : public std::enable_shared_from_this<Bonjour> {
+private:
+	struct priv;
+public:
+	typedef std::shared_ptr<Bonjour> Ptr;
+	typedef std::function<void(std::string /* IP */, std::string /* host */, std::string /* service_name */)> ReplyFn;
+	typedef std::function<void()> CompleteFn;
+
+	Bonjour(std::string service, std::string protocol = "tcp");
+	Bonjour(Bonjour &&other);
+	~Bonjour();
+
+	Bonjour& set_timeout(unsigned timeout);
+	Bonjour& on_reply(ReplyFn fn);
+	Bonjour& on_complete(CompleteFn fn);
+
+	Ptr lookup();
+
+	static void pokus();    // XXX: remove
+private:
+	std::unique_ptr<priv> p;
+};
+
+
+}
+
+#endif
diff --git a/xs/src/slic3r/Utils/OctoPrint.cpp b/xs/src/slic3r/Utils/OctoPrint.cpp
index 019a4e238..58530833b 100644
--- a/xs/src/slic3r/Utils/OctoPrint.cpp
+++ b/xs/src/slic3r/Utils/OctoPrint.cpp
@@ -15,90 +15,90 @@ namespace Slic3r {
 
 
 OctoPrint::OctoPrint(DynamicPrintConfig *config) :
-    host(config->opt_string("octoprint_host")),
-    apikey(config->opt_string("octoprint_apikey")),
-    cafile(config->opt_string("octoprint_cafile"))
+	host(config->opt_string("octoprint_host")),
+	apikey(config->opt_string("octoprint_apikey")),
+	cafile(config->opt_string("octoprint_cafile"))
 {}
 
 std::string  OctoPrint::test() const
 {
-    // Since the request is performed synchronously here,
-    // it is ok to refer to `res` from within the closure
-    std::string res;
-
-    auto http = Http::get(std::move(make_url("api/version")));
-    set_auth(http);
-    http.on_error([&](std::string, std::string error, unsigned status) {
-            res = format_error(error, status);
-        })
-        .perform_sync();
-
-    return res;
+	// Since the request is performed synchronously here,
+	// it is ok to refer to `res` from within the closure
+	std::string res;
+
+	auto http = Http::get(std::move(make_url("api/version")));
+	set_auth(http);
+	http.on_error([&](std::string, std::string error, unsigned status) {
+			res = format_error(error, status);
+		})
+		.perform_sync();
+
+	return res;
 }
 
 void OctoPrint::send_gcode(int windowId, int completeEvt, int errorEvt, const std::string &filename, bool print) const
 {
-    auto http = Http::post(std::move(make_url("api/files/local")));
-    set_auth(http);
-    http.form_add("print", print ? "true" : "false")
-        .form_add_file("file", filename)
-        .on_complete([=](std::string body, unsigned status) {
-            wxWindow *window = GUI::get_widget_by_id(windowId);
-            wxCommandEvent* evt = new wxCommandEvent(completeEvt);
-            evt->SetString("G-code file successfully uploaded to the OctoPrint server");
-            evt->SetInt(100);
-            wxQueueEvent(window, evt);
-        })
-        .on_error([=](std::string body, std::string error, unsigned status) {
-            wxWindow *window = GUI::get_widget_by_id(windowId);
-
-            wxCommandEvent* evt_complete = new wxCommandEvent(completeEvt);
-            evt_complete->SetInt(100);
-            wxQueueEvent(window, evt_complete);
-
-            wxCommandEvent* evt_error = new wxCommandEvent(errorEvt);
-            evt_error->SetString(wxString::Format("Error while uploading to the OctoPrint server: %s", format_error(error, status)));
-            wxQueueEvent(window, evt_error);
-        })
-        .perform();
+	auto http = Http::post(std::move(make_url("api/files/local")));
+	set_auth(http);
+	http.form_add("print", print ? "true" : "false")
+		.form_add_file("file", filename)
+		.on_complete([=](std::string body, unsigned status) {
+			wxWindow *window = GUI::get_widget_by_id(windowId);
+			wxCommandEvent* evt = new wxCommandEvent(completeEvt);
+			evt->SetString("G-code file successfully uploaded to the OctoPrint server");
+			evt->SetInt(100);
+			wxQueueEvent(window, evt);
+		})
+		.on_error([=](std::string body, std::string error, unsigned status) {
+			wxWindow *window = GUI::get_widget_by_id(windowId);
+
+			wxCommandEvent* evt_complete = new wxCommandEvent(completeEvt);
+			evt_complete->SetInt(100);
+			wxQueueEvent(window, evt_complete);
+
+			wxCommandEvent* evt_error = new wxCommandEvent(errorEvt);
+			evt_error->SetString(wxString::Format("Error while uploading to the OctoPrint server: %s", format_error(error, status)));
+			wxQueueEvent(window, evt_error);
+		})
+		.perform();
 }
 
 void OctoPrint::set_auth(Http &http) const
 {
-    http.header("X-Api-Key", apikey);
+	http.header("X-Api-Key", apikey);
 
-    if (! cafile.empty()) {
-        http.ca_file(cafile);
-    }
+	if (! cafile.empty()) {
+		http.ca_file(cafile);
+	}
 }
 
 std::string OctoPrint::make_url(const std::string &path) const
 {
-    if (host.find("http://") == 0 || host.find("https://") == 0) {
-        if (host.back() == '/') {
-            return std::move((boost::format("%1%%2%") % host % path).str());
-        } else {
-            return std::move((boost::format("%1%/%2%") % host % path).str());
-        }
-    } else {
-        return std::move((boost::format("http://%1%/%2%") % host % path).str());
-    }
+	if (host.find("http://") == 0 || host.find("https://") == 0) {
+		if (host.back() == '/') {
+			return std::move((boost::format("%1%%2%") % host % path).str());
+		} else {
+			return std::move((boost::format("%1%/%2%") % host % path).str());
+		}
+	} else {
+		return std::move((boost::format("http://%1%/%2%") % host % path).str());
+	}
 }
 
 std::string OctoPrint::format_error(std::string error, unsigned status)
 {
-    if (status != 0) {
-        std::string res{"HTTP "};
-        res.append(std::to_string(status));
-
-        if (status == 401) {
-            res.append(": Invalid API key");
-        }
-
-        return std::move(res);
-    } else {
-        return std::move(error);
-    }
+	if (status != 0) {
+		std::string res{"HTTP "};
+		res.append(std::to_string(status));
+
+		if (status == 401) {
+			res.append(": Invalid API key");
+		}
+
+		return std::move(res);
+	} else {
+		return std::move(error);
+	}
 }
 
 
diff --git a/xs/src/slic3r/Utils/OctoPrint.hpp b/xs/src/slic3r/Utils/OctoPrint.hpp
index c5ed70ab5..1d70a087d 100644
--- a/xs/src/slic3r/Utils/OctoPrint.hpp
+++ b/xs/src/slic3r/Utils/OctoPrint.hpp
@@ -14,19 +14,19 @@ class Http;
 class OctoPrint
 {
 public:
-    OctoPrint(DynamicPrintConfig *config);
+	OctoPrint(DynamicPrintConfig *config);
 
-    std::string test() const;
-    // XXX: style
-    void send_gcode(int windowId, int completeEvt, int errorEvt, const std::string &filename, bool print = false) const;
+	std::string test() const;
+	// XXX: style
+	void send_gcode(int windowId, int completeEvt, int errorEvt, const std::string &filename, bool print = false) const;
 private:
-    std::string host;
-    std::string apikey;
-    std::string cafile;
+	std::string host;
+	std::string apikey;
+	std::string cafile;
 
-    void set_auth(Http &http) const;
-    std::string make_url(const std::string &path) const;
-    static std::string format_error(std::string error, unsigned status);
+	void set_auth(Http &http) const;
+	std::string make_url(const std::string &path) const;
+	static std::string format_error(std::string error, unsigned status);
 };