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 (
	// NetworkCache provides cache for network-related values.
	NetworkCache struct {
		cache  gcache.Cache
		logger *zap.Logger
	}

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

const (
	DefaultNetworkCacheLifetime = 1 * time.Minute
	networkCacheSize            = 2
	networkInfoKey              = "network_info"
	netmapKey                   = "netmap"
)

// DefaultNetworkConfig returns new default cache expiration values.
func DefaultNetworkConfig(logger *zap.Logger) *NetworkCacheConfig {
	return &NetworkCacheConfig{
		Lifetime: DefaultNetworkCacheLifetime,
		Logger:   logger,
	}
}

// NewNetworkCache creates an object of NetworkCache.
func NewNetworkCache(config *NetworkCacheConfig) *NetworkCache {
	gc := gcache.New(networkCacheSize).LRU().Expiration(config.Lifetime).Build()
	return &NetworkCache{cache: gc, logger: config.Logger}
}

func (c *NetworkCache) GetNetworkInfo() *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 *NetworkCache) PutNetworkInfo(info netmap.NetworkInfo) error {
	return c.cache.Set(networkInfoKey, info)
}

func (c *NetworkCache) GetNetmap() *netmap.NetMap {
	entry, err := c.cache.Get(netmapKey)
	if err != nil {
		return nil
	}

	result, ok := entry.(netmap.NetMap)
	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 *NetworkCache) PutNetmap(nm netmap.NetMap) error {
	return c.cache.Set(netmapKey, nm)
}