package main

import (
	"errors"
	"regexp"
	"strconv"
)

func setNetwork(env map[string]string) error {
	if ok := validateEthernetAddr(env["ethaddr"]); !ok {
		return errors.New("invalid ethernet address")
	}

	if ok := validateIpAddr(env["ipaddr"]); !ok {
		return errors.New("invalid ip address")
	}

	if ok := validateIpAddr(env["netmask"]); !ok {
		return errors.New("invalid netmask")
	}

	if ok := validateIpAddr(env["gateway"]); !ok {
		return errors.New("invalid gateway")
	}

	if hasDualNetwork {
		if ok := validateEthernetAddr(env["ethaddr2"]); !ok {
			return errors.New("invalid ethernet address 2")
		}

		if ok := validateIpAddr(env["ipaddr2"]); !ok {
			return errors.New("invalid ip address 2")
		}

		if ok := validateIpAddr(env["netmask2"]); !ok {
			return errors.New("invalid netmask 2")
		}

		if ok := validateIpAddr(env["gateway2"]); !ok {
			return errors.New("invalid gateway 2")
		}
	}

	return setEnv(0, env)
}

func validateEthernetAddr(addr string) (ok bool) {
	r := regexp.MustCompile(`([0-9a-fA-F]{2}):([0-9a-fA-F]{2}):([0-9a-fA-F]{2}):([0-9a-fA-F]{2}):([0-9a-fA-F]{2}):([0-9a-fA-F]{2})`)
	s := r.FindStringSubmatch(addr)
	if len(s) != 7 || s[0] != addr {
		return false
	}

	for i, v := range s {
		if i == 0 {
			continue
		}

		u, err := strconv.ParseUint(v, 16, 8)
		if err != nil {
			return false
		}

		if u > 255 {
			return false
		}
	}

	return true
}

func validateIpAddr(addr string) (ok bool) {
	r := regexp.MustCompile(`([0-9]+)\.([0-9]+)\.([0-9]+)\.([0-9]+)`)
	s := r.FindStringSubmatch(addr)
	if len(s) != 5 || s[0] != addr {
		return false
	}

	for i, v := range s {
		if i == 0 {
			continue
		}

		u, err := strconv.ParseUint(v, 10, 8)
		if err != nil {
			return false
		}

		if u > 255 {
			return false
		}
	}

	return true
}