sim-modem/api/modem/internet/ic.go

package internet

import (
	"fmt"
	"io"
	"log"
	"os/exec"
	"strings"

	"gitea.unprism.ru/KRBL/sim-modem/api/modem/at"
)

type conn struct {
	logger *log.Logger
	port   at.Port

	pppPort string

	isConnectExecuted bool
	isInited          bool
}

type Conn interface {
	Init(pppPort string) error

	Connect() error
	Disconnect() error

	IsConnected() bool // Check interface existance
	Ping() error

	io.Closer
}

func New(logger *log.Logger, port at.Port) Conn {
	return &conn{
		logger:            logger,
		port:              port,
		isConnectExecuted: false,
		isInited:          false,
	}
}

func (c *conn) Init(pppPort string) error {
	c.pppPort = pppPort
	// Setup only setup
	if err := c.setup(); err != nil {
		return fmt.Errorf("setup: %w", err)
	}
	c.isInited = true
	return nil
}

func (c *conn) Connect() error {
	if !c.isInited {
		return fmt.Errorf("internet submodule is not inited")
	}
	// Check is already connected
	if c.isConnectExecuted {
		return fmt.Errorf("already connected")
	}
	// Check signal
	// if ok, err := utils.CheckService(c.port, c.logger); err != nil || !ok {
	// 	if err != nil {
	// 		return fmt.Errorf("check service: %w", err)
	// 	}
	// 	return fmt.Errorf("no service")
	// }

	resp, err := exec.Command("pon", pppConfigName).Output()
	if err != nil {
		return fmt.Errorf("execute pon cmd: %w", err)
	}
	if len(resp) > 0 {
		c.logger.Println("pon response:", string(resp))
	}
	c.isConnectExecuted = true

	// Set default route

	c.logger.Println("\x1b[38;2;0;255;0mInternet connected.\x1b[38;2;255;255;255m")
	return nil
}

func (c *conn) Disconnect() error {
	// return nil // Temporary do not turn off inet
	if !c.isConnectExecuted {
		return nil
		// return fmt.Errorf("internet is not connected")
	}
	c.isConnectExecuted = false
	resp, err := exec.Command("poff", pppConfigName).Output()
	if err != nil {
		return fmt.Errorf("execute poff cmd: %w", err)
	}
	if len(resp) > 0 {
		c.logger.Println("poff response:", string(resp))
	}
	c.isConnectExecuted = false
	return nil
}

func (c *conn) Ping() error {
	// Test - try to connect to Google DNS
	//   ping -I ppp0 8.8.8.8
	resp, err := exec.Command("ping", "8.8.8.8").Output()
	if err != nil {
		c.logger.Println("Ping default interface cmd error:", err)
	}
	c.logger.Println("Ping  default interface resp:", string(resp))

	resp, err = exec.Command("ping", "-I", "ppp0", "8.8.8.8").Output()
	if err != nil {
		c.logger.Println("Ping ppp0 interface cmd error:", err)
	}
	c.logger.Println("Ping ppp0 interface resp:", string(resp))

	if strings.Contains(string(resp), "Destination Host Unreachable") || strings.Contains(string(resp), "Destination Net Unreachable") {
		return fmt.Errorf("ping response: %s", string(resp))
	}
	return nil
}

func (c *conn) IsConnected() bool {
	if !c.isConnectExecuted {
		return false
	}
	// Make "ifconfig" request
	resp, err := exec.Command("ifconfig").Output()
	if err != nil {
		c.logger.Println("ifconfig cmd error:", err.Error())
		return false
	}
	lines := strings.Split(string(resp), "\n")
	for _, l := range lines {
		if len(l) == 0 {
			continue
		}
		if l[0] == ' ' {
			continue
		}
		interfaceName := strings.Split(l, ":")[0]
		if interfaceName == "ppp0" {
			return true
		}
	}
	return false // Did not found
}

func (c *conn) Close() error {
	c.isInited = false
	if err := c.Disconnect(); err != nil {
		return fmt.Errorf("diconnect: %w", err)
	}
	return nil
}