package dhcp

import (
	"errors"
	"fmt"
	"io"
)

type OptionTag uint8

type Option func(req *BootRequest, r io.Reader) error

const (
	OptionTagPadding              OptionTag = 0
	OptionTagHostName             OptionTag = 12
	OptionTagMessageType          OptionTag = 53
	OptionTagParameterRequestList OptionTag = 55
	OptionTagEnd                  OptionTag = 255
)

var optionRegistry = map[OptionTag]Option{
	OptionTagPadding:              OptionPad,
	OptionTagHostName:             OptionHostName,
	OptionTagMessageType:          OptionMessageType,
	OptionTagParameterRequestList: OptionParameterRequestList,
	OptionTagEnd:                  OptionEnd,
}

func OptionPad(req *BootRequest, r io.Reader) error {
	return nil
}

func OptionHostName(req *BootRequest, r io.Reader) error {
	return errors.New("dhcp: option not implemented yet")
}

func OptionMessageType(req *BootRequest, r io.Reader) error {
	return errors.New("dhcp: option not implemented yet")
}

func OptionParameterRequestList(req *BootRequest, r io.Reader) error {
	return errors.New("dhcp: option not implemented yet")
}

func OptionEnd(req *BootRequest, r io.Reader) error {
	return errors.New("dhcp: option not implemented yet")
}

func ReadOption(req *BootRequest, tag byte, r io.Reader) error {
	opt := OptionTag(tag)
	if f, ok := optionRegistry[opt]; ok {
		return f(req, r)

	}

	return fmt.Errorf("dhcp: unknown/unhandled option %d", opt)
}