From e6803275a0244ca85efd978a222212d6b4d1c958 Mon Sep 17 00:00:00 2001
From: Green Sky <green@g-s.xyz>
Date: Sat, 8 Oct 2022 00:15:51 +0200
Subject: [PATCH] hs init recv logic, + fs send init ack (not tracking it yet)

---
 ngc_ext_common.hpp |  4 ++--
 ngc_ft1.cpp        | 12 ++++++++++++
 ngc_hs1.cpp        | 47 ++++++++++++++++++++++++++++++++++++++++++++--
 3 files changed, 59 insertions(+), 4 deletions(-)

diff --git a/ngc_ext_common.hpp b/ngc_ext_common.hpp
index 541b686..d1818f1 100644
--- a/ngc_ext_common.hpp
+++ b/ngc_ext_common.hpp
@@ -28,7 +28,7 @@ enum _PacketType : uint8_t {
 	// - peer_key bytes (the msg_ids are from)
 	// - 1 byte (uint8_t count ids, can be 0)
 	// - array [
-	//   - msg_id bytes (the message id
+	//   - msg_id bytes (the message id)
 	// - ]
 	HS1_RESPONSE_LAST_IDS,
 
@@ -49,7 +49,7 @@ enum _PacketType : uint8_t {
 
 	// acknowlage init (like an accept)
 	// like tox ft control continue
-	// - 1 byte (temporary_file_tf_id)
+	// - 1 byte (transfer_id)
 	FT1_INIT_ACK,
 
 	// TODO: init deny, speed up non acceptance
diff --git a/ngc_ft1.cpp b/ngc_ft1.cpp
index 1250b5e..ed34f9e 100644
--- a/ngc_ft1.cpp
+++ b/ngc_ft1.cpp
@@ -300,6 +300,7 @@ static void _handle_FT1_INIT(
 	fprintf(stderr, "]\n");
 
 	// check if slot free ?
+	// did we allready ack this and the other side just did not see the ack?
 
 	NGC_FT1_recv_init_cb* fn_ptr = nullptr;
 	if (ngc_ext_ctx->ngc_ft1_ctx->cb_init.count(file_kind)) {
@@ -316,8 +317,19 @@ static void _handle_FT1_INIT(
 
 	if (accept_ft) {
 		// send ack
+		// - 1 byte packet id
+		// - 1 byte transfer_id
+		std::vector<uint8_t> pkg;
+		pkg.push_back(FT1_INIT_ACK);
+		pkg.push_back(transfer_id);
+
+		// lossless
+		tox_group_send_custom_private_packet(tox, group_number, peer_number, true, pkg.data(), pkg.size(), nullptr);
+
+		fprintf(stderr, "accepted init\n");
 	} else {
 		// TODO deny?
+		fprintf(stderr, "rejected init\n");
 	}
 }
 
diff --git a/ngc_hs1.cpp b/ngc_hs1.cpp
index 65650db..4a445ec 100644
--- a/ngc_hs1.cpp
+++ b/ngc_hs1.cpp
@@ -39,7 +39,7 @@ struct NGC_HS1 {
 			uint32_t peer_number; // the peer we requested the message from
 			float time_since_ft_activity {0.f};
 		};
-		std::map<uint32_t, PendingFTRequest> pending;
+		std::map<uint32_t, PendingFTRequest> pending; // key msg_id
 
 		// dont start immediatly
 		float time_since_last_request_sent {0.f};
@@ -465,7 +465,50 @@ static bool _handle_HS1_ft_init_message(
 	const size_t file_size
 ) {
 	fprintf(stderr, "-------hs handle ft init\n");
-	return false; // deny
+
+	// peer id and msg id from file id
+	// TODO: replace, remote crash
+	assert(file_id_size == TOX_GROUP_PEER_PUBLIC_KEY_SIZE+sizeof(uint32_t));
+
+	// get peer_key from file_id
+	_PeerKey peer_key;
+	std::copy(file_id, file_id+peer_key.size(), peer_key.data.begin());
+
+	// get msg_id from file_id
+	// HACK: little endian
+	uint32_t msg_id;
+	uint8_t* tmp_ptr = reinterpret_cast<uint8_t*>(&msg_id);
+	std::copy(file_id+TOX_GROUP_PEER_PUBLIC_KEY_SIZE, file_id+TOX_GROUP_PEER_PUBLIC_KEY_SIZE+sizeof(uint32_t), tmp_ptr);
+
+	// did we ask for this?
+
+	// get group id
+	_GroupKey g_id{};
+	{ // TODO: error
+		tox_group_get_chat_id(tox, group_number, g_id.data.data(), nullptr);
+	}
+
+	auto& group = ngc_ext_ctx->ngc_hs1_ctx->history[g_id];
+
+	auto& pending = group.peers[peer_key].pending;
+
+	if (!pending.count(msg_id)) {
+		// we did not ask for this
+		// TODO: accept?
+		fprintf(stderr, "ft init from peer we did not ask\n");
+		return false; // deny
+	}
+
+	if (pending.at(msg_id).peer_number != peer_number) {
+		// wrong peer ?
+		fprintf(stderr, "ft init from peer we did not ask while asking someone else\n");
+		return false; // deny
+	}
+
+	// TODO: more?
+	pending.at(msg_id).time_since_ft_activity = 0.f;
+
+	return true; // accept
 }
 
 #define _HS1_HAVE(x, error) if ((length - curser) < (x)) { error; }