Initial commit

hardware/hardware.go

@@ -0,0 +1,18 @@
+package hardware
+
+type (
+	Hardware interface {
+		Read() (uint16, error)
+	}
+	Client struct {
+		hardware Hardware
+	}
+)
+
+func NewClient(h Hardware) Client {
+	return Client{hardware: h}
+}
+
+func (c Client) Read() (uint16, error) {
+	return c.hardware.Read()
+}

hardware/mock.go

@@ -0,0 +1,22 @@
+package hardware
+
+type Mock struct {
+	currValue int16
+	delta     int16
+}
+
+func NewMock() *Mock {
+	return &Mock{currValue: 0, delta: 1}
+}
+
+func (m *Mock) Read() (uint16, error) {
+	m.currValue += m.delta
+
+	if m.currValue >= 100 {
+		m.delta = -1
+	} else if m.currValue <= 0 {
+		m.delta = 1
+	}
+
+	return uint16(m.currValue), nil
+}

hardware/siemens.go

@@ -0,0 +1,26 @@
+package hardware
+
+import (
+	"encoding/binary"
+
+	snap7 "github.com/danclive/snap7-go"
+)
+
+type Siemens struct {
+	client snap7.Snap7Client
+}
+
+func NewSiemens(client snap7.Snap7Client) Siemens {
+	return Siemens{client: client}
+}
+
+func (s Siemens) Read() (uint16, error) {
+	db, err := s.client.DBRead(1, 0, 8)
+	if err != nil {
+		return 0, err
+	}
+
+	value := binary.BigEndian.Uint16(db[2:4])
+
+	return value, nil
+}