package net

import "math/rand/v2"

const LUX_NONCE_MAX = 128

// Anti replay measure.
type LuxNonceList struct {
	nonces []uint64
}

func GenerateLuxNonce() uint64 {
	return rand.Uint64()
}

func NewLuxNonceList() LuxNonceList {
	return LuxNonceList{
		nonces: make([]uint64, 0),
	}
}

func (list *LuxNonceList) RotateOrFail(newNonce uint64) bool {
	for _, nonce := range list.nonces {
		if nonce == newNonce {
			return false
		}
	}

	if len(list.nonces) == LUX_NONCE_MAX {
		// rotate
		for i := LUX_NONCE_MAX - 1; i > 0; i-- {
			list.nonces[i] = list.nonces[i-1]
		}

		list.nonces[0] = newNonce
	} else {
		// append to head
		list.nonces = append([]uint64{newNonce}, list.nonces...)
	}

	return true
}

func (list *LuxNonceList) Flush() {
	list.nonces = make([]uint64, 0)
}

func (list *LuxNonceList) Get(idx int) uint64 {
	return list.nonces[idx]
}