feat(ezcoo): serial driver for EZCOO HDMI matrix

pkg/ezcoo/device.go

@@ -0,0 +1,162 @@
+package ezcoo
+
+import (
+	"bufio"
+	"fmt"
+	"log/slog"
+	"strings"
+	"time"
+
+	"go.bug.st/serial"
+)
+
+func (d *Device) GetStatus() State {
+	d.mu.RLock()
+	defer d.mu.RUnlock()
+	return d.current
+}
+
+func (d *Device) SetOutput(out, in int) {
+	cmd := fmt.Sprintf("EZS OUT%d VS IN%d", out, in)
+	select {
+	case d.cmds <- cmd:
+	default:
+		slog.Warn("command queue full, dropping", "cmd", cmd)
+	}
+	d.poll()
+	time.AfterFunc(time.Second, d.poll)
+}
+
+func (d *Device) poll() {
+	select {
+	case d.cmds <- pollCmd:
+	default:
+	}
+}
+
+func (d *Device) Run(onState func(State), onAvailable func(bool), done <-chan struct{}) {
+	if d.cfg.PollInterval > 0 {
+		go d.pollLoop(done)
+	}
+
+	for {
+		port, err := Open(d.cfg)
+		if err != nil {
+			slog.Error("open serial", "err", err, "retry_in", "5s")
+			select {
+			case <-done:
+				return
+			case <-time.After(5 * time.Second):
+				continue
+			}
+		}
+
+		slog.Info("serial connected", "port", d.cfg.Port)
+		onAvailable(true)
+		d.poll()
+
+		d.runPort(port, onState, done)
+		onAvailable(false)
+
+		select {
+		case <-done:
+			return
+		default:
+			slog.Warn("serial disconnected, reconnecting in 5s")
+			time.Sleep(5 * time.Second)
+		}
+	}
+}
+
+func (d *Device) runPort(port serial.Port, onState func(State), done <-chan struct{}) {
+	defer port.Close()
+
+	reader := bufio.NewReader(port)
+	lineCh := make(chan string, 32)
+	go func() {
+		for {
+			line, err := reader.ReadString('\n')
+			line = strings.TrimSpace(line)
+			if err != nil {
+				slog.Error("serial read", "err", err)
+				close(lineCh)
+				return
+			}
+			if line == "" {
+				continue
+			}
+			select {
+			case lineCh <- line:
+			case <-done:
+				close(lineCh)
+				return
+			}
+		}
+	}()
+
+	collectUntil := time.Time{}
+
+	for {
+		var collectCh <-chan time.Time
+		if !collectUntil.IsZero() {
+			collectCh = time.After(time.Until(collectUntil))
+		}
+
+		select {
+		case <-done:
+			return
+
+		case cmd, ok := <-d.cmds:
+			if !ok {
+				return
+			}
+			slog.Debug("serial tx", "cmd", cmd)
+			if _, err := port.Write([]byte(cmd + "\r\n")); err != nil {
+				slog.Error("serial write", "err", err)
+				return
+			}
+			if strings.HasPrefix(cmd, "EZG OUT") {
+				collectUntil = time.Now().Add(500 * time.Millisecond)
+			}
+
+		case line, ok := <-lineCh:
+			if !ok {
+				slog.Error("serial reader closed")
+				return
+			}
+			d.applyLine(line)
+
+		case <-collectCh:
+			collectUntil = time.Time{}
+			onState(d.GetStatus())
+		}
+	}
+}
+
+func (d *Device) applyLine(line string) {
+	slog.Debug("serial rx", "line", line)
+	m := reOutVS.FindStringSubmatch(line)
+	if m == nil {
+		return
+	}
+	out, _ := parseInt(m[1])
+	in, _ := parseInt(m[2])
+	if out >= 1 && out <= 2 && in >= 1 && in <= 4 {
+		d.mu.Lock()
+		d.current[out-1] = in
+		d.mu.Unlock()
+	}
+}
+
+func (d *Device) pollLoop(done <-chan struct{}) {
+	t := time.NewTicker(d.cfg.PollInterval)
+	defer t.Stop()
+	for {
+		select {
+		case <-done:
+			return
+		case <-t.C:
+			d.poll()
+		}
+	}
+}