Append an optional station log and announce the software after login.

A log path that cannot be written leaves the station on the reflector, and the reflector learns which program joined.

Co-authored-by: Cursor <cursoragent@cursor.com>

station/log.go

@@ -0,0 +1,125 @@
+package station
+
+import (
+	"fmt"
+	"os"
+	"strings"
+	"time"
+)
+
+// Close releases the log file. It is safe to call more than once.
+func (s *Station) Close() {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	s.closeLogLocked()
+}
+
+func (s *Station) openLog() {
+	f, err := os.OpenFile(s.logPath, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0o600)
+	if err != nil {
+		s.logNotice = "Cannot write " + s.logPath
+		if s.state.Talker == "" {
+			s.state.Detail = s.logNotice
+		}
+		return
+	}
+	s.logFile = f
+}
+
+func (s *Station) closeLogLocked() {
+	if s.logFile != nil {
+		s.logFile.Close()
+		s.logFile = nil
+	}
+}
+
+func (s *Station) writeLog(ts time.Time, msg string) {
+	if s.logFile == nil {
+		return
+	}
+	line := ts.Format(time.RFC3339) + " " + msg + "\n"
+	if _, err := s.logFile.Write([]byte(line)); err != nil {
+		s.closeLogLocked()
+		if s.logNotice == "" {
+			s.logNotice = "Cannot write " + s.logPath
+		}
+	}
+}
+
+func (s *Station) noteTransmitLocked() {
+	s.noteTransmitAt(s.clock.Now())
+}
+
+func (s *Station) noteTransmitAt(now time.Time) {
+	tx := s.transmitting()
+	if tx && !s.sending {
+		s.sending = true
+		s.sendStart = now
+		return
+	}
+	if !tx && s.sending {
+		start := s.sendStart
+		s.sending = false
+		s.writeLog(start, fmt.Sprintf("sending for %d seconds.", wholeSeconds(start, now)))
+	}
+}
+
+func (s *Station) closeTalkerLocked(now time.Time) {
+	if s.talkCall == "" {
+		return
+	}
+	call := s.talkCall
+	start := s.talkStart
+	s.talkCall = ""
+	s.writeLog(start, fmt.Sprintf("%s talked for %d seconds.", call, wholeSeconds(start, now)))
+}
+
+func (s *Station) noteDownLocked(now time.Time, dial bool) {
+	s.closeTalkerLocked(now)
+	s.state.Connection = "Disconnected"
+	s.remoteTalker = ""
+	s.roomBusy = false
+	s.noteTransmitAt(now)
+	switch {
+	case s.up:
+		s.up = false
+		s.outage = true
+		s.writeLog(now, "disconnected")
+	case dial && !s.outage:
+		s.outage = true
+		s.writeLog(now, "disconnected")
+	}
+	s.publish()
+}
+
+func (s *Station) endFatal(msg string, log bool) {
+	s.mu.Lock()
+	defer s.mu.Unlock()
+	if s.fatal != "" {
+		return
+	}
+	now := s.clock.Now()
+	s.closeTalkerLocked(now)
+	s.fatal = msg
+	s.remoteTalker = ""
+	s.roomBusy = false
+	s.noteTransmitAt(now)
+	if log {
+		s.up = false
+		s.outage = true
+		s.writeLog(now, oneLine(msg))
+	}
+	s.publish()
+}
+
+func wholeSeconds(start, end time.Time) int {
+	d := end.Sub(start)
+	if d <= 0 {
+		return 0
+	}
+	return int(d / time.Second)
+}
+
+func oneLine(msg string) string {
+	return strings.NewReplacer("\r\n", " ", "\n", " ", "\r", " ").Replace(msg)
+}