feat: New Station Control, allow to control Webswitch 1216H or KMTronic

internal/rotgenius/rotgenius.go

@@ -0,0 +1,193 @@
+// Package rotgenius drives a 4O3A Rotator Genius over its native TCP text
+// protocol (rev 4, default port 9006). All data is fixed-length extended-ASCII;
+// there is no sequence/framing wrapper — you send a short command and read back a
+// fixed-length reply.
+//
+// Commands used here:
+//
+//	|h                    read heading + full state (both rotators)
+//	|A<rot><az3>          move rotator <rot> ('1'|'2') to azimuth az3 (000..360)
+//	|P<rot> / |M<rot>     rotate CW / CCW
+//	|S                    stop all movement
+//
+// The |h reply is 72 bytes: "|h" + Active[1] + Panic[1] then, per rotator,
+// CurrentAzimuth[3] LimitCW[3] LimitCCW[3] Config[1] Moving[1] Offset[4]
+// TargetAzimuth[3] StartAzimuth[3] Limit[1] Name[12]. Numeric fields may be
+// space-padded; a CurrentAzimuth of 999 means the sensor is not connected.
+package rotgenius
+
+import (
+	"fmt"
+	"net"
+	"strconv"
+	"strings"
+	"time"
+)
+
+const (
+	defaultPort = 9006
+	dialTimeout = 4 * time.Second
+	ioTimeout   = 4 * time.Second
+	hdrReplyLen = 72 // fixed length of the |h reply
+)
+
+// Status is one rotator's live state parsed from a |h reply.
+type Status struct {
+	Azimuth   int  // current heading in degrees (0..360)
+	Connected bool // false when the sensor reports 999 (not connected)
+	Moving    int  // 0 not moving, 1 CW, 2 CCW
+	Target    int  // target azimuth when moving (else -1)
+}
+
+// Client is a stateless connector: each call opens a short-lived TCP connection,
+// mirroring how the PstRotator client works, so there is no socket to manage.
+type Client struct {
+	host string
+	port int
+}
+
+func New(host string, port int) *Client {
+	if port <= 0 {
+		port = defaultPort
+	}
+	return &Client{host: host, port: port}
+}
+
+func (c *Client) dial() (net.Conn, error) {
+	d := net.Dialer{Timeout: dialTimeout}
+	conn, err := d.Dial("tcp", net.JoinHostPort(c.host, strconv.Itoa(c.port)))
+	if err != nil {
+		return nil, err
+	}
+	_ = conn.SetDeadline(time.Now().Add(ioTimeout))
+	return conn, nil
+}
+
+// exchange sends cmd and returns up to max bytes of the reply.
+func (c *Client) exchange(cmd string, max int) ([]byte, error) {
+	conn, err := c.dial()
+	if err != nil {
+		return nil, err
+	}
+	defer conn.Close()
+	if _, err := conn.Write([]byte(cmd)); err != nil {
+		return nil, fmt.Errorf("write %q: %w", cmd, err)
+	}
+	buf := make([]byte, 0, max)
+	tmp := make([]byte, max)
+	for len(buf) < max {
+		n, rerr := conn.Read(tmp)
+		if n > 0 {
+			buf = append(buf, tmp[:n]...)
+		}
+		if rerr != nil {
+			break // deadline or EOF — return what we have and let the parser judge
+		}
+	}
+	return buf, nil
+}
+
+// atoiField trims the space-padding a Rotator Genius field may carry and parses
+// it. An empty or non-numeric field yields 0.
+func atoiField(s string) int {
+	n, _ := strconv.Atoi(strings.TrimSpace(s))
+	return n
+}
+
+// Heading reads the current azimuth of the given rotator (1 or 2). raw is the
+// decoded field for diagnostics.
+func (c *Client) Heading(rotator int) (Status, string, error) {
+	st, err := c.Read(rotator)
+	if err != nil {
+		return Status{}, "", err
+	}
+	return st, strconv.Itoa(st.Azimuth), nil
+}
+
+// Read fetches and parses the full |h reply for one rotator (1 or 2).
+func (c *Client) Read(rotator int) (Status, error) {
+	if rotator != 1 && rotator != 2 {
+		rotator = 1
+	}
+	reply, err := c.exchange("|h", hdrReplyLen)
+	if err != nil {
+		return Status{}, err
+	}
+	i := strings.Index(string(reply), "|h")
+	if i < 0 || len(reply)-i < hdrReplyLen {
+		return Status{}, fmt.Errorf("rotgenius: short |h reply (%d bytes)", len(reply))
+	}
+	p := reply[i:]
+	// Per-rotator block base: rotator 1 at offset 4, rotator 2 at 4+34=38.
+	base := 4
+	if rotator == 2 {
+		base = 38
+	}
+	// Within a rotator block: CurrentAzimuth@0, LimitCW@3, LimitCCW@6, Config@9,
+	// Moving@10, Offset@11, TargetAzimuth@15, StartAzimuth@18, Limit@21, Name@22.
+	cur := atoiField(string(p[base : base+3]))
+	moving := atoiField(string(p[base+10 : base+11]))
+	target := atoiField(string(p[base+15 : base+18]))
+	st := Status{Azimuth: cur, Moving: moving, Connected: cur != 999, Target: -1}
+	if target != 999 {
+		st.Target = target
+	}
+	return st, nil
+}
+
+// GoTo moves the rotator to az (0..360). The reply's status byte is 'K' on
+// accept, 'F' on reject.
+func (c *Client) GoTo(rotator, az int) error {
+	if rotator != 1 && rotator != 2 {
+		rotator = 1
+	}
+	if az < 0 {
+		az = 0
+	}
+	if az > 360 {
+		az = 360
+	}
+	reply, err := c.exchange(fmt.Sprintf("|A%d%03d", rotator, az), 8)
+	if err != nil {
+		return err
+	}
+	return checkKF(reply, "GoTo")
+}
+
+// Stop halts all movement.
+func (c *Client) Stop() error {
+	reply, err := c.exchange("|S", 8)
+	if err != nil {
+		return err
+	}
+	return checkKF(reply, "Stop")
+}
+
+// CW / CCW nudge a rotator; it runs to its limit unless stopped.
+func (c *Client) CW(rotator int) error  { return c.rotate('P', rotator) }
+func (c *Client) CCW(rotator int) error { return c.rotate('M', rotator) }
+
+func (c *Client) rotate(cmd byte, rotator int) error {
+	if rotator != 1 && rotator != 2 {
+		rotator = 1
+	}
+	reply, err := c.exchange(fmt.Sprintf("|%c%d", cmd, rotator), 8)
+	if err != nil {
+		return err
+	}
+	return checkKF(reply, string(cmd))
+}
+
+// checkKF reads the accept/reject status: 'K' ok, 'F' failed. The reply carries
+// no other letters (the rest is the header + digits), so scanning for them is
+// unambiguous.
+func checkKF(reply []byte, what string) error {
+	s := string(reply)
+	if strings.ContainsRune(s, 'K') {
+		return nil
+	}
+	if strings.ContainsRune(s, 'F') {
+		return fmt.Errorf("rotgenius: %s rejected by the controller", what)
+	}
+	return fmt.Errorf("rotgenius: no reply to %s", what)
+}