Method requestFileReference

Telegram/SourceFiles/apiwrap.cpp:2538–2588

template <typename Request>
void ApiWrap::requestFileReference(
		Data::FileOrigin origin,
		FileReferencesHandler &&handler,
		Request &&data) {
	const auto i = _fileReferenceHandlers.find(origin);
	if (i != end(_fileReferenceHandlers)) {
		i->second.push_back(std::move(handler));
		return;
	}
	auto handlers = std::vector<FileReferencesHandler>();
	handlers.push_back(std::move(handler));
	_fileReferenceHandlers.emplace(origin, std::move(handlers));

	request(std::move(data)).done([=](const auto &result) {
		const auto parsed = Data::GetFileReferences(result);
		for (const auto &p : parsed.data) {
			// Unpack here the parsed pair by hand to workaround a GCC bug.
			// See https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87122
			const auto &origin = p.first;
			const auto &reference = p.second;
			const auto documentId = std::get_if<DocumentFileLocationId>(
				&origin);
			if (documentId) {
				_session->data().document(
					documentId->id
				)->refreshFileReference(reference);
			}
			const auto photoId = std::get_if<PhotoFileLocationId>(&origin);
			if (photoId) {
				_session->data().photo(
					photoId->id
				)->refreshFileReference(reference);
			}
		}
		const auto i = _fileReferenceHandlers.find(origin);
		Assert(i != end(_fileReferenceHandlers));
		auto handlers = std::move(i->second);
		_fileReferenceHandlers.erase(i);
		for (auto &handler : handlers) {
			handler(parsed);
		}
	}).fail([=] {
		const auto i = _fileReferenceHandlers.find(origin);
		Assert(i != end(_fileReferenceHandlers));
		auto handlers = std::move(i->second);
		_fileReferenceHandlers.erase(i);
		for (auto &handler : handlers) {
			handler(UpdatedFileReferences());
		}
	}).send();
}

void ApiWrap::refreshFileReference(
		Data::FileOrigin origin,