Method resolve

Telegram/SourceFiles/data/data_download_manager.cpp:644–717

}

void DownloadManager::resolve(
		not_null<Main::Session*> session,
		SessionData &data) {
	const auto guard = gsl::finally([&] {
		checkFullResolveDone();
	});
	if (data.resolveSentTotal >= data.resolveNeeded
		|| data.resolveSentTotal >= kMaxResolvePerAttempt) {
		return;
	}
	struct Prepared {
		uint64 peerAccessHash = 0;
		QVector<MTPInputMessage> ids;
	};
	auto &owner = session->data();
	auto prepared = base::flat_map<PeerId, Prepared>();
	auto last = begin(data.downloaded);
	auto from = last + (data.resolveNeeded - data.resolveSentTotal);
	for (auto i = from; i != last;) {
		auto &id = *--i;
		const auto msgId = id.itemId.msg;
		const auto info = QFileInfo(id.path);
		if (!info.exists() || info.size() != id.size) {
			// Mark as deleted.
			id.path = QString();
		} else if (!owner.message(id.itemId) && IsServerMsgId(msgId)) {
			const auto groupByPeer = peerIsChannel(id.itemId.peer)
				? id.itemId.peer
				: session->userPeerId();
			auto &perPeer = prepared[groupByPeer];
			if (peerIsChannel(id.itemId.peer) && !perPeer.peerAccessHash) {
				perPeer.peerAccessHash = id.peerAccessHash;
			}
			perPeer.ids.push_back(MTP_inputMessageID(MTP_int(msgId.bare)));
		}
		if (++data.resolveSentTotal >= kMaxResolvePerAttempt) {
			break;
		}
	}
	const auto check = [=] {
		auto &data = sessionData(session);
		if (!data.resolveSentRequests) {
			resolveRequestsFinished(session, data);
		}
	};
	const auto requestFinished = [=] {
		--sessionData(session).resolveSentRequests;
		check();
	};
	for (auto &[peer, perPeer] : prepared) {
		if (const auto channelId = peerToChannel(peer)) {
			session->api().request(MTPchannels_GetMessages(
				MTP_inputChannel(
					MTP_long(channelId.bare),
					MTP_long(perPeer.peerAccessHash)),
				MTP_vector<MTPInputMessage>(perPeer.ids)
			)).done([=](const MTPmessages_Messages &result) {
				session->data().processExistingMessages(