From 5dfa9e4a00db4102387ae6dc13395849e42bc679 Mon Sep 17 00:00:00 2001
From: cam <cameron.ryan.pears@gmail.com>
Date: Mon, 13 May 2024 23:33:59 +1200
Subject: [PATCH] Added dbus call to set APN

---
 cmd/modemd/modemController.go | 33 +++++++++++++++++++++++++++++++++
 cmd/modemd/service.go         | 10 ++++++++++
 2 files changed, 43 insertions(+)

diff --git a/cmd/modemd/modemController.go b/cmd/modemd/modemController.go
index ea0c005..5cc2b66 100644
--- a/cmd/modemd/modemController.go
+++ b/cmd/modemd/modemController.go
@@ -258,6 +258,7 @@ func (mc *ModemController) GetStatus() (map[string]interface{}, error) {
 		modem["manufacturer"] = valueOrErrorStr(mc.getManufacturer())
 		modem["model"] = valueOrErrorStr(mc.getModel())
 		modem["serial"] = valueOrErrorStr(mc.getSerialNumber())
+		modem["apn"] = valueOrErrorStr(mc.getAPN())
 		status["modem"] = modem
 
 		signal := make(map[string]interface{})
@@ -419,6 +420,38 @@ func (mc *ModemController) getSerialNumber() (string, error) {
 // 9.1 Overview of AT Commands for SMS Control
 // Firmware upgrades?
 
+func (mc *ModemController) getAPN() (string, error) {
+	out, err := mc.RunATCommand("AT+CGDCONT?")
+	if err != nil {
+		return "", err
+	}
+	out = strings.TrimPrefix(out, "+CGDCONT:")
+	out = strings.TrimSpace(out)
+	parts := strings.Split(out, ",")
+	if len(parts) < 3 {
+		return "", fmt.Errorf("invalid CGDCONT format %s", out)
+	}
+	apn := parts[2]
+	apn = strings.TrimPrefix(apn, "\"")
+	apn = strings.TrimSuffix(apn, "\"")
+	return apn, nil
+}
+
+func (mc *ModemController) setAPN(apn string) error {
+	_, err := mc.RunATCommand(fmt.Sprintf("AT+CGDCONT=1,\"IP\",\"%s\"", apn))
+	if err != nil {
+		return err
+	}
+	readAPN, err := mc.getAPN()
+	if err != nil {
+		return err
+	}
+	if readAPN != apn {
+		return fmt.Errorf("failed to set APN, APN is '%s' when it was set as '%s'", readAPN, apn)
+	}
+	return err
+}
+
 func (mc *ModemController) CheckSimCard() (string, error) {
 	// Enable verbose error messages.
 	_, err := mc.RunATCommand("AT+CMEE=2")
diff --git a/cmd/modemd/service.go b/cmd/modemd/service.go
index 8a1df6b..3f47566 100644
--- a/cmd/modemd/service.go
+++ b/cmd/modemd/service.go
@@ -100,6 +100,16 @@ func (s service) GetStatus() (map[string]interface{}, *dbus.Error) {
 	return status, nil
 }
 
+func (s service) SetAPN(apn string) *dbus.Error {
+	log.Println("Setting APN to", apn)
+	err := s.mc.setAPN(apn)
+	if err != nil {
+		log.Println(err)
+		return makeDbusError("SetAPN", err)
+	}
+	return nil
+}
+
 /*
 func (s service) GPSOn() *dbus.Error {
 	err := s.mc.EnableGPS()