package cache

import (
	"github.com/hashicorp/golang-lru/v2/expirable"
	"time"
)

type ttlCache struct {
	buf *expirable.LRU[string, []byte]
}

//goland:noinspection GoUnusedExportedFunction
func NewTTLCache(size int, ttl time.Duration) Cache {
	c := &ttlCache{}
	c.buf = expirable.NewLRU[string, []byte](size, nil, ttl)
	return c
}

func (c *ttlCache) Get(elm Element) error {
	var k = elm.Key()

	buf, ok := c.buf.Get(k)
	if !ok {
		return ErrorNotFound
	}

	if err := elm.Unmarshal(buf); err != nil {
		c.buf.Remove(k)
		return err
	}

	return nil
}

func (c *ttlCache) Set(elm Element) error {
	var k = elm.Key()

	buf, err := elm.Marshal()
	if err != nil {
		c.buf.Remove(k)
		return err
	}

	c.buf.Add(k, buf)
	return nil
}

func (c *ttlCache) String() string {
	return "ttl_lru_cache"
}

func (c *ttlCache) Close() error {
	if c.buf != nil {
		c.buf.Purge()
	}

	return nil
}