package kvcache

import (
	"time"

	"github.com/fanjindong/go-cache"
)

const (
	NoExpiration time.Duration = -1
)

type KVCache[V any] struct {
	c          cache.ICache
	expiration time.Duration
}

func NewKVCache[V any]() *KVCache[V] {
	return NewExpireStore[V](NoExpiration)
}

func NewExpireStore[V any](defaultExpiration time.Duration, iopts ...cache.ICacheOption) *KVCache[V] {
	opts := []cache.ICacheOption{
		cache.WithShards(16),
		cache.WithClearInterval(time.Minute),
	}
	opts = append(opts, iopts...)
	c := cache.NewMemCache(opts...)
	return &KVCache[V]{
		c:          c,
		expiration: defaultExpiration,
	}
}

func (s *KVCache[V]) Set(k string, v V) {
	if s.expiration == NoExpiration {
		s.c.Set(k, v)
		return
	}
	s.c.Set(k, v, cache.WithEx(s.expiration))
}

func (s *KVCache[V]) SetEx(k string, v V, ex time.Duration) {
	s.c.Set(k, v, cache.WithEx(ex))
}

func (s *KVCache[V]) Get(k string) (v V, ok bool) {
	val, ok := s.c.Get(k)
	if !ok {
		return
	}
	v = val.(V)
	return
}

func (s *KVCache[V]) Delete(keys ...string) {
	s.c.Del(keys...)
}

func (s *KVCache[V]) ForEach(f func(k string, v V)) {
	for k, v := range s.c.ToMap() {
		f(k, v.(V))
	}
}

func (s *KVCache[V]) Count() int {
	return len(s.c.ToMap())
}