Separate Homematic code

Similar to a previous refactoring of the MQTT-related code this removes
all Homematic logic to a dedicated file.

The only connection to the outside is the `tx chan MQTTMessage` channel
and the `HomematicRun()` function.

This makes the code more modular.

1 files changed, 77 insertions, 0 deletions

diff --git a/homematic.go b/homematic.go
new file mode 100644
index 0000000..ae12760
--- /dev/null
+++ b/homematic.go
@@ -0,0 +1,77 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"time"
+
+	"xengineering.eu/homematic-go/homematic"
+)
+
+const (
+	OPENCCU        = `http://127.0.0.1:8080`
+	POLLING_PERIOD = 50 * time.Millisecond
+)
+
+func HomematicRun(tx chan MQTTMessage) {
+	req, inventory, err := Start()
+	if err != nil {
+		log.Fatalf("Failed startup process: %v", err)
+	}
+
+	cache := NewCache(tx)
+
+	for {
+		start := time.Now()
+
+		states, err := Poll(req, inventory)
+		if err != nil {
+			log.Fatalf("Failed to poll states: %v", err)
+		}
+
+		cache.Update(states)
+
+		WaitUntil(start.Add(POLLING_PERIOD))
+	}
+
+}
+
+func Start() (homematic.Requester, homematic.Devices, error) {
+	var req homematic.Requester
+	var inventory homematic.Devices
+	var err error
+
+	req = homematic.NewRequester(OPENCCU)
+	log.Printf("Created Homematic requester (%s).", OPENCCU)
+
+	inventory, err = req.ListDevices()
+	if err != nil {
+		return req, inventory, fmt.Errorf("Failed getting initial device list: %w", err)
+	}
+	log.Printf("Retrieved Homematic inventory with %d devices.", len(inventory))
+
+	return req, inventory, nil
+}
+
+func Poll(req homematic.Requester, inventory homematic.Devices) (States, error) {
+	states := make(States)
+
+	for _, device := range inventory {
+		if device.Type == `SHUTTER_CONTACT` {
+			state, err := req.GetValue(device.Address)
+			if err != nil {
+				return states, fmt.Errorf("Failed to get value: %w", err)
+			}
+			states[device.Address] = state
+		}
+	}
+
+	return states, nil
+}
+
+func WaitUntil(deadline time.Time) {
+	duration := time.Until(deadline)
+	if duration > 0 {
+		time.Sleep(duration)
+	}
+}