package swModels

import (
	"regexp"
	"strconv"
	"strings"
)

var (
	IPACLRE    = regexp.MustCompile(`(?i)(i|)(p|pv6)\s+access-list\s+(\S+)\n((.|\n)*?)(\n\S|$)`)
	IPEXTACLRE = regexp.MustCompile(`(?i)(i|)(p|pv6)\s+access-list\s+extended\s+(\S+)\n((.|\n)*?)(\n\S|$)`)
	LINEACLRE  = regexp.MustCompile(`(?i)([0-9]+)\s+(.*?)$`)
)

type (
	AccessLists struct {
		AccessLists []*AccessList `json:"access_lists"`
	}

	AccessList struct {
		Name     string     `json:"name"`
		IPV6     bool       `json:"ipv6"`
		Extended bool       `json:"extended"`
		Rules    []*ACLRule `json:"rules"`
	}

	ACLRule struct {
		Line int    `json:"line"`
		Rule string `json:"rule"`
	}
)

func (a *AccessLists) Parse(s *string) {
	for _, acl := range IPACLRE.FindAllStringSubmatch(*s, -1) {
		a.AccessLists = append(a.AccessLists, &AccessList{
			Name:  acl[3],
			IPV6:  isV6(&acl[2]),
			Rules: parseACL(&acl[4]),
		})
	}

	for _, acl := range IPEXTACLRE.FindAllStringSubmatch(*s, -1) {
		a.AccessLists = append(a.AccessLists, &AccessList{
			Name:     acl[3],
			IPV6:     isV6(&acl[2]),
			Extended: true,
			Rules:    parseACL(&acl[4]),
		})
	}
}

func isV6(s *string) bool {
	if *s == "pv6" {
		return true
	}
	return false
}

func parseACL(s *string) (rules []*ACLRule) {
	for i, r := range strings.Split(*s, "\n") {
		r = strings.TrimRight(r, " ")
		r = strings.TrimLeft(r, " ")
		if r == "" {
			continue
		}
		m := LINEACLRE.FindStringSubmatch(r)
		if len(m) == 0 {
			rules = append(rules, &ACLRule{
				Line: i + 1,
				Rule: r,
			})
			continue
		}
		rules = append(rules, &ACLRule{
			Line: func() int {
				if n, err := strconv.Atoi(m[1]); err == nil {
					return n
				}
				return 0
			}(),
			Rule: m[2],
		})
	}
	return
}