package cache

import (
	"fmt"
	"time"

	"git.frostfs.info/TrueCloudLab/frostfs-s3-gw/internal/logs"
	"git.frostfs.info/TrueCloudLab/frostfs-sdk-go/netmap"
	"github.com/bluele/gcache"
	"go.uber.org/zap"
)

type (
	// NetworkInfoCache provides cache for network info.
	NetworkInfoCache struct {
		cache  gcache.Cache
		logger *zap.Logger
	}

	// NetworkInfoCacheConfig stores expiration params for cache.
	NetworkInfoCacheConfig struct {
		Lifetime time.Duration
		Logger   *zap.Logger
	}
)

const (
	DefaultNetworkInfoCacheLifetime = 1 * time.Minute
	networkInfoCacheSize            = 1
	networkInfoKey                  = "network_info"
)

// DefaultNetworkInfoConfig returns new default cache expiration values.
func DefaultNetworkInfoConfig(logger *zap.Logger) *NetworkInfoCacheConfig {
	return &NetworkInfoCacheConfig{
		Lifetime: DefaultNetworkInfoCacheLifetime,
		Logger:   logger,
	}
}

// NewNetworkInfoCache creates an object of NetworkInfoCache.
func NewNetworkInfoCache(config *NetworkInfoCacheConfig) *NetworkInfoCache {
	gc := gcache.New(networkInfoCacheSize).LRU().Expiration(config.Lifetime).Build()
	return &NetworkInfoCache{cache: gc, logger: config.Logger}
}

func (c *NetworkInfoCache) Get() *netmap.NetworkInfo {
	entry, err := c.cache.Get(networkInfoKey)
	if err != nil {
		return nil
	}

	result, ok := entry.(netmap.NetworkInfo)
	if !ok {
		c.logger.Warn(logs.InvalidCacheEntryType, zap.String("actual", fmt.Sprintf("%T", entry)),
			zap.String("expected", fmt.Sprintf("%T", result)))
		return nil
	}

	return &result
}

func (c *NetworkInfoCache) Put(info netmap.NetworkInfo) error {
	return c.cache.Set(networkInfoKey, info)
}