package serial

import (
	"time"

	"github.com/argandas/serial"
)

// Reader defines the interface for serial port operations.
type Reader interface {
	ReadLine() (string, error)
	Close() error
	IsOpen() bool
}

// Port wraps a serial port connection.
type Port struct {
	sp     *serial.SerialPort
	opened bool
}

// Open opens a serial port with the given device and baudrate.
func Open(device string, baudrate int) (*Port, error) {
	sp := serial.New()
	sp.EOL('\r')
	sp.Verbose = false

	err := sp.Open(device, baudrate, 3*time.Second)
	if err != nil {
		return nil, err
	}

	return &Port{sp: sp, opened: true}, nil
}

// ReadLine reads one line from the serial port.
func (p *Port) ReadLine() (string, error) {
	return p.sp.ReadLine()
}

// Close closes the serial port.
func (p *Port) Close() error {
	p.opened = false
	return nil
}

// IsOpen returns whether the port is currently open.
func (p *Port) IsOpen() bool {
	return p.opened
}