package devices

import (
	"fmt"
	"log"

	"go.bug.st/serial"
)

type Coin int

func (c Coin) Value() int {
	return int(c)
}

func (c Coin) String() string {
	switch c {
	case Quarter:
		return "Quarter (25c)"
	case Dime:
		return "Dime (10c)"
	case Nickel:
		return "Nickel (5c)"
	case Penny:
		return "Penny (1c)"
	default:
		return fmt.Sprintf("Unknown Coin (%d)", c)
	}
}

const (
	Quarter Coin = 25
	Dime    Coin = 10
	Nickel  Coin = 5
	Penny   Coin = 1
)

type CoinAcceptor interface {
	Start() error
	Close() error
	Coins() <-chan Coin
}

type DG600F struct {
	PortName string
	BaudRate int
	coins    chan Coin
	port     serial.Port
}

func (c *DG600F) Start() error {
	mode := &serial.Mode{
		BaudRate: c.BaudRate,
		DataBits: 8,
		Parity:   serial.EvenParity,
		StopBits: serial.TwoStopBits,
	}

	port, err := serial.Open(c.PortName, mode)
	if err != nil {
		return err
	}

	c.port = port
	c.coins = make(chan Coin, 10)
	log.Println("Coin acceptor started")

	go c.listen()

	return nil
}

func (c *DG600F) listen() {
	for {
		data := make([]byte, 1)
		_, err := c.port.Read(data)
		if err != nil {
			log.Println("Error reading from port:", err)
			return
		}

		if data[0] == 0x00 {
			continue
		}

		c.coins <- Coin(data[0])
	}
}

func (c *DG600F) Close() error {
	return c.port.Close()
}

func (c *DG600F) Coins() <-chan Coin {
	return c.coins
}