From 4d223c1cdc3a6f4650496e651c0fc552b8c24abf Mon Sep 17 00:00:00 2001
From: Abhishek Kondur <abhi281342@gmail.com>
Date: Mon, 10 Apr 2023 12:14:40 +0400
Subject: [PATCH] api for signalling peer

---
 controllers/hosts.go | 66 ++++++++++++++++++++++++++++++++++++++++++++
 models/host.go       | 11 ++++++++
 2 files changed, 77 insertions(+)

diff --git a/controllers/hosts.go b/controllers/hosts.go
index a9380d22..5bc6fc77 100644
--- a/controllers/hosts.go
+++ b/controllers/hosts.go
@@ -28,6 +28,7 @@ func hostHandlers(r *mux.Router) {
 	r.HandleFunc("/api/hosts/{hostid}/relay", logic.SecurityCheck(false, http.HandlerFunc(deleteHostRelay))).Methods(http.MethodDelete)
 	r.HandleFunc("/api/hosts/adm/authenticate", authenticateHost).Methods(http.MethodPost)
 	r.HandleFunc("/api/v1/host", authorize(true, false, "host", http.HandlerFunc(pull))).Methods(http.MethodGet)
+	r.HandleFunc("/api/hosts/{hostid}/signalpeer", logic.SecurityCheck(false, http.HandlerFunc(createHostRelay))).Methods(http.MethodPost)
 }
 
 // swagger:route GET /api/hosts hosts getHosts
@@ -445,3 +446,68 @@ func authenticateHost(response http.ResponseWriter, request *http.Request) {
 	response.Header().Set("Content-Type", "application/json")
 	response.Write(successJSONResponse)
 }
+
+// swagger:route POST /api/hosts/{hostid}/signalpeer signalPeer
+//
+// send signal to peer.
+//
+//			Schemes: https
+//
+//			Security:
+//	  		oauth
+//
+//			Responses:
+//				200: nodeResponse
+func signalPeer(w http.ResponseWriter, r *http.Request) {
+	var params = mux.Vars(r)
+	hostid := params["hostid"]
+	// confirm host exists
+	currHost, err := logic.GetHost(hostid)
+	if err != nil {
+		logger.Log(0, r.Header.Get("user"), "failed to get host:", currHost.ID.String(), err.Error())
+		logic.ReturnErrorResponse(w, r, logic.FormatError(err, "badrequest"))
+		return
+	}
+	var signal models.Signal
+	w.Header().Set("Content-Type", "application/json")
+	err = json.NewDecoder(r.Body).Decode(&signal)
+	if err != nil {
+		logger.Log(0, r.Header.Get("user"), "error decoding request body: ", err.Error())
+		logic.ReturnErrorResponse(w, r, logic.FormatError(err, "badrequest"))
+		return
+	}
+	if signal.ToHostPubKey == "" || signal.TurnRelayEndpoint == nil {
+		msg := "insufficient data to signal peer"
+		logger.Log(0, r.Header.Get("user"), msg)
+		logic.ReturnErrorResponse(w, r, logic.FormatError(errors.New(msg), "badrequest"))
+		return
+	}
+	hosts, err := logic.GetAllHosts()
+	if err != nil {
+		logic.ReturnErrorResponse(w, r, logic.FormatError(err, "internal"))
+		return
+	}
+	// push the signal to host through mq
+	found := false
+	for _, hostI := range hosts {
+		if hostI.PublicKey.String() == signal.ToHostPubKey {
+			// found host publish message and break
+			found = true
+			err = mq.HostUpdate(&models.HostUpdate{
+				Action: models.SignalHost,
+				Host:   hostI,
+				Signal: signal,
+			})
+			if err != nil {
+				logic.ReturnErrorResponse(w, r, logic.FormatError(errors.New("failed to publish signal to peer: "+err.Error()), "badrequest"))
+				return
+			}
+		}
+	}
+	if !found {
+		logic.ReturnErrorResponse(w, r, logic.FormatError(errors.New("failed to signal, peer not found"), "badrequest"))
+		return
+	}
+	w.WriteHeader(http.StatusOK)
+	json.NewEncoder(w).Encode(signal)
+}
diff --git a/models/host.go b/models/host.go
index 6495d512..eb73cff2 100644
--- a/models/host.go
+++ b/models/host.go
@@ -102,6 +102,8 @@ func ParseBool(s string) bool {
 type HostMqAction string
 
 const (
+	// SignalHost - const for host signal action
+	SignalHost = "SIGNAL_HOST"
 	// UpdateHost - constant for host update action
 	UpdateHost = "UPDATE_HOST"
 	// DeleteHost - constant for host delete action
@@ -121,9 +123,18 @@ type HostUpdate struct {
 	Action HostMqAction
 	Host   Host
 	Node   Node
+	Signal Signal
 }
 
+// HostTurnRegister - struct for host turn registration
 type HostTurnRegister struct {
 	HostID       string `json:"host_id"`
 	HostPassHash string `json:"host_pass_hash"`
 }
+
+// Signal - struct for signalling peer
+type Signal struct {
+	FromHostPubKey    string          `json:"from_host_pubkey"`
+	TurnRelayEndpoint *net.PacketConn `json:"turn_relay_addr"`
+	ToHostPubKey      string          `json:"to_host_pubkey"`
+}