From a86c3dc3b92a7eb1850280958c008edb1b8feff2 Mon Sep 17 00:00:00 2001
From: Mike Shoup <mike@shoup.io>
Date: Sun, 30 Sep 2018 09:00:20 -0600
Subject: [PATCH] Skeleton for web frontend

---
 main.go | 10 ++++++++++
 run.go  |  8 +++++++-
 web.go  | 21 +++++++++++++++++++++
 3 files changed, 38 insertions(+), 1 deletion(-)
 create mode 100644 web.go

diff --git a/main.go b/main.go
index 66f043d..e159522 100644
--- a/main.go
+++ b/main.go
@@ -36,6 +36,9 @@ func main() {
 	// run is tracking whether or not the thermostats should run
 	run := true
 
+	// done is used to signal the web frontend to stop
+	done := make(chan bool)
+
 	sig := make(chan os.Signal)
 	signal.Notify(sig, os.Interrupt, syscall.SIGTERM)
 	signal.Notify(sig, os.Interrupt, syscall.SIGINT)
@@ -43,6 +46,7 @@ func main() {
 	go func() {
 		<-sig
 		run = false
+		done <- true
 	}()
 
 	sc := make(chan State)
@@ -53,6 +57,12 @@ func main() {
 		wg.Add(1)
 		go RunThermostat(sensor, sc, &run, &wg)
 	}
+
+	// Launch the web frontend
+	wg.Add(1)
+	RunWeb(sc, done, &wg)
+
+	// Wait for all threads to stop
 	wg.Wait()
 
 	// Close the GPIO access
diff --git a/run.go b/run.go
index a16c6c3..2342e59 100644
--- a/run.go
+++ b/run.go
@@ -107,7 +107,13 @@ func RunThermostat(sensor Sensor, sc chan<- State, run *bool, wg *sync.WaitGroup
 
 		s.Temp = t
 		log.Printf("%s Temp: %.2f, Cooling: %t, Heating: %t, Duration: %.1f", sensor.Alias, s.Temp, s.Cooling, s.Heating, min)
-		sc <- s
+
+		select {
+		case sc <- s:
+			break
+		default:
+			break
+		}
 	}
 
 	PinSwitch(cpin, false, sensor.CoolInvert)
diff --git a/web.go b/web.go
new file mode 100644
index 0000000..489bd25
--- /dev/null
+++ b/web.go
@@ -0,0 +1,21 @@
+package main
+
+import (
+	"sync"
+)
+
+// RunWeb launches a web server
+func RunWeb(sc <-chan State, done <-chan bool, wg *sync.WaitGroup) {
+	states := make(map[string]State)
+
+	go func() {
+		for {
+			s := <-sc
+			states[s.ID] = s
+		}
+	}()
+
+	<-done
+
+	wg.Done()
+}