From f8a063312c52a0d2ea78df499e792362486ef916 Mon Sep 17 00:00:00 2001
From: Jared Boone <jboone@earfeast.com>
Date: Wed, 13 Jan 2016 16:32:56 -0800
Subject: [PATCH] AISModel receive packets from baseband, notifies AISView.

Use Signal class to distribute packets to multiple listeners.
---
 firmware/application/ais_app.cpp | 34 +++++++++++++-------------------
 firmware/application/ais_app.hpp | 19 +++++++++++++++---
 2 files changed, 30 insertions(+), 23 deletions(-)

diff --git a/firmware/application/ais_app.cpp b/firmware/application/ais_app.cpp
index a96b1fdf..b8d84565 100644
--- a/firmware/application/ais_app.cpp
+++ b/firmware/application/ais_app.cpp
@@ -89,6 +89,18 @@ AISModel::AISModel() {
 	receiver_model.set_baseband_bandwidth(1750000);
 
 	log_file.open_for_append("ais.txt");
+
+	EventDispatcher::message_map().register_handler(Message::ID::AISPacket,
+		[this](Message* const p) {
+			const auto message = static_cast<const AISPacketMessage*>(p);
+			const ais::Packet packet { message->packet };
+			this->on_packet(packet);
+		}
+	);
+}
+
+AISModel::~AISModel() {
+	EventDispatcher::message_map().unregister_handler(Message::ID::AISPacket);
 }
 
 bool AISModel::on_packet(const ais::Packet& packet) {
@@ -110,31 +122,13 @@ bool AISModel::on_packet(const ais::Packet& packet) {
 		log_file.write_entry(packet.received_at(), entry);
 	}
 
+	packet_signal.emit(packet);
+
 	return true;
 }	
 
 namespace ui {
 
-void AISView::on_show() {
-	View::on_show();
-
-	EventDispatcher::message_map().register_handler(Message::ID::AISPacket,
-		[this](Message* const p) {
-			const auto message = static_cast<const AISPacketMessage*>(p);
-			const ais::Packet packet { message->packet };
-			if( this->model.on_packet(packet) ) {
-				this->on_packet(packet);
-			}
-		}
-	);
-}
-
-void AISView::on_hide() {
-	EventDispatcher::message_map().unregister_handler(Message::ID::AISPacket);
-
-	View::on_hide();
-}
-
 void AISView::truncate_entries() {
 	while(recent.size() > 64) {
 		recent.pop_back();
diff --git a/firmware/application/ais_app.hpp b/firmware/application/ais_app.hpp
index 4a11efaf..65bd9e26 100644
--- a/firmware/application/ais_app.hpp
+++ b/firmware/application/ais_app.hpp
@@ -25,8 +25,12 @@
 #include "ui_widget.hpp"
 #include "log_file.hpp"
 
+#include "message.hpp"
+
 #include "ais_packet.hpp"
 
+#include "signal.hpp"
+
 #include "lpc43xx_cpp.hpp"
 using namespace lpc43xx;
 
@@ -66,11 +70,14 @@ struct AISRecentEntry {
 class AISModel {
 public:
 	AISModel();
+	~AISModel();
 
-	bool on_packet(const ais::Packet& packet);
+	Signal<const ais::Packet&> packet_signal;
 
 private:
 	LogFile log_file;
+
+	bool on_packet(const ais::Packet& packet);
 };
 
 namespace ui {
@@ -79,10 +86,15 @@ class AISView : public View {
 public:
 	AISView() {
 		flags.focusable = true;
+
+		packet_signal_token = model.packet_signal += [this](const ais::Packet& packet) {
+			this->on_packet(packet);
+		};
 	}
 
-	void on_show() override;
-	void on_hide() override;
+	~AISView() {
+		model.packet_signal -= packet_signal_token;
+	}
 
 	void paint(Painter& painter) override;
 
@@ -93,6 +105,7 @@ public:
 
 private:
 	AISModel model;
+	SignalToken packet_signal_token;
 
 	using EntryKey = ais::MMSI;
 	EntryKey selected_key;