package store

import (
	"net/netip"
	"strings"
)

// EffectivePeerEnabledOnCreate matches API/JSON decoding: omitted "enabled" unmarshals as false in Go,
// but new peers should be enabled by default. If session_state is non-empty, false is preserved
// (agent-managed rows may be intentionally disabled).
func EffectivePeerEnabledOnCreate(inEnabled bool, sessionState string) bool {
	if inEnabled {
		return true
	}
	if strings.TrimSpace(sessionState) != "" {
		return false
	}
	return true
}

// ParsePeerNeighbor parses a BGP neighbor value for BIRD output: a plain IPv4/IPv6
// address, or a host prefix (/32 or /128) which is a common input mistake.
func ParsePeerNeighbor(s string) (netip.Addr, bool) {
	s = strings.TrimSpace(s)
	if s == "" {
		return netip.Addr{}, false
	}
	if addr, err := netip.ParseAddr(s); err == nil {
		return addr, true
	}
	pfx, err := netip.ParsePrefix(s)
	if err != nil {
		return netip.Addr{}, false
	}
	addr := pfx.Addr()
	if addr.Is4() && pfx.Bits() == 32 {
		return addr, true
	}
	if addr.Is6() && pfx.Bits() == 128 {
		return addr, true
	}
	return netip.Addr{}, false
}

// NormalizePeerNeighborString returns the canonical host address string for storage
// and BIRD, or false if s is not a usable neighbor.
func NormalizePeerNeighborString(s string) (string, bool) {
	addr, ok := ParsePeerNeighbor(s)
	if !ok {
		return "", false
	}
	return addr.String(), true
}