From 8318cc5c210452737713a4e8341e078712c92474 Mon Sep 17 00:00:00 2001
From: Djeeberjr <djeeberjr@gmail.com>
Date: Tue, 1 Mar 2022 17:28:15 +0100
Subject: [PATCH] implemented distance vector routing

---
 src/kernel/net/Net.hx     |  2 +-
 src/kernel/net/Package.hx |  1 +
 src/kernel/net/Routing.hx | 39 +++++++++++++++++++++++++++++++++++++++
 3 files changed, 41 insertions(+), 1 deletion(-)

diff --git a/src/kernel/net/Net.hx b/src/kernel/net/Net.hx
index 1e2e72d..13ee49b 100644
--- a/src/kernel/net/Net.hx
+++ b/src/kernel/net/Net.hx
@@ -59,7 +59,7 @@ class Net {
 					if (responseBus.exists(pack.msgID)) {
 						responseBus[pack.msgID].invoke(pack);
 					}
-				case RouteDiscover(_) | RouteDiscoverResponse(_):
+				case RouteDiscover(_) | RouteDiscoverResponse(_) | RouteDiscoverUpdate(_):
 					// Delegate to Routing
 					Routing.instance.handleRoutePackage(pack,interf);
 			}
diff --git a/src/kernel/net/Package.hx b/src/kernel/net/Package.hx
index 25cba5e..9509cc6 100644
--- a/src/kernel/net/Package.hx
+++ b/src/kernel/net/Package.hx
@@ -8,6 +8,7 @@ enum PackageTypes {
 	Response;
 	RouteDiscover(reachableIDs: Array<{id:NetworkID,cost:Int}>);
 	RouteDiscoverResponse(reachableIDs: Array<{id:NetworkID,cost:Int}>);
+	RouteDiscoverUpdate(reachableIDs: Array<{id:NetworkID,cost:Int}>);
 }
 
 /**
diff --git a/src/kernel/net/Routing.hx b/src/kernel/net/Routing.hx
index 660bcb3..01ad4d9 100644
--- a/src/kernel/net/Routing.hx
+++ b/src/kernel/net/Routing.hx
@@ -22,10 +22,13 @@ class Routing {
 	**/
 	public static var instance:Routing;
 
+	public static inline final UPDATE_WAIT_TIME:Float = 3;
+
 	public final onNewNeigbor:Signal<Int>;
 
 	private final onNewNeigborTrigger:SignalTrigger<NetworkID> = Signal.trigger();
 	private final routingTable:Map<NetworkID, Route> = new Map();
+	private var routeUpdateInQueue: Bool = false;
 
 	@:allow(kernel.Init)
 	private function new() {
@@ -40,6 +43,35 @@ class Routing {
 		}
 	}
 
+	private function prepareRouteUpdate() {
+		if (this.routeUpdateInQueue){
+			return;
+		}
+
+		this.routeUpdateInQueue = true;
+
+		new Timer(UPDATE_WAIT_TIME,()->{
+			brodcastUpdatedRoutes();
+			this.routeUpdateInQueue = false;
+		});
+	}
+
+	private function brodcastUpdatedRoutes() {
+		var pack: Package = {
+			type: RouteDiscoverUpdate(genRouteList()),
+			toID: Net.BRODCAST_PORT,
+			msgID: null,
+			fromID: Net.instance.networkID,
+			data: null,
+			ttl: 0, // Prevent forwarding
+		};
+
+		for (modem in Peripheral.instance.getModems()) {
+
+			modem.send(Net.BRODCAST_PORT, Net.instance.networkID,pack);
+		}
+	}
+
 	/**
 		Handle incomming packages that involve route discovery.
 	**/
@@ -57,6 +89,11 @@ class Routing {
 					addPossibleRoute(route.id,interf,route.cost,pack.fromID);
 				}
 				true;
+			case RouteDiscoverUpdate(routes):
+				for (route in routes) {
+					addPossibleRoute(route.id,interf,route.cost,pack.fromID);
+				}
+				false;
 			default:
 				Log.error("Expected RouteDiscover or RouteDiscoverResponse type");
 				false;
@@ -118,11 +155,13 @@ class Routing {
 			if (this.routingTable[toID].cost > fullCost){
 				Log.info("Better route: " + toID + " -> " + interf.name() + ":$"+fullCost);
 				this.routingTable[toID] = {interf:interf,cost:cost + interf.getBaseRoutingCost(),rep: rep};
+				this.prepareRouteUpdate();
 			}
 		}else{
 			this.routingTable[toID] = {interf:interf,cost:cost + interf.getBaseRoutingCost(),rep: rep};
 			Log.info("New route: " + toID + " -> " + interf.name() + ":$"+fullCost);
 			this.onNewNeigborTrigger.trigger(toID);
+			this.prepareRouteUpdate();
 		}
 	}