package cache

import (
	"Open_IM/pkg/common/tracelog"
	"Open_IM/pkg/utils"
	"context"
	"encoding/json"
	"github.com/dtm-labs/rockscache"
	"github.com/go-redis/redis/v8"
	"time"
)

const (
	blackIDsKey     = "BLACK_IDS:"
	blackExpireTime = time.Second * 60 * 60 * 12
)

type BlackCache interface {
	//get blackIDs from cache
	GetBlackIDs(ctx context.Context, userID string, fn func(ctx context.Context, userID string) ([]string, error)) (blackIDs []string, err error)
	//del user's blackIDs cache, exec when a user's black list changed
	DelBlackIDs(ctx context.Context, userID string) (err error)
}

type BlackCacheRedis struct {
	expireTime time.Duration
	rcClient   *rockscache.Client
}

func NewBlackCacheRedis(rdb redis.UniversalClient, blackDB BlackCache, options rockscache.Options) *BlackCacheRedis {
	return &BlackCacheRedis{
		expireTime: blackExpireTime,
		rcClient:   rockscache.NewClient(rdb, options),
	}
}

func (b *BlackCacheRedis) getBlackIDsKey(ownerUserID string) string {
	return blackIDsKey + ownerUserID
}

func (b *BlackCacheRedis) GetBlackIDs(ctx context.Context, userID string) (blackIDs []string, err error) {
	getBlackIDList := func() (string, error) {
		blackIDs, err := b.blackDB.GetBlackIDs(ctx, userID)
		if err != nil {
			return "", utils.Wrap(err, "")
		}
		bytes, err := json.Marshal(blackIDs)
		if err != nil {
			return "", utils.Wrap(err, "")
		}
		return string(bytes), nil
	}
	defer func() {
		tracelog.SetCtxDebug(ctx, utils.GetFuncName(1), err, "userID", userID, "blackIDList", blackIDs)
	}()
	blackIDListStr, err := b.rcClient.Fetch(blackListCache+userID, b.expireTime, getBlackIDList)
	if err != nil {
		return nil, utils.Wrap(err, "")
	}
	err = json.Unmarshal([]byte(blackIDListStr), &blackIDs)
	return blackIDs, utils.Wrap(err, "")
}

func (b *BlackCacheRedis) DelBlackIDs(ctx context.Context, userID string) (err error) {
	defer func() {
		tracelog.SetCtxDebug(ctx, utils.GetFuncName(1), err, "userID", userID)
	}()
	return b.rcClient.TagAsDeleted(blackListCache + userID)
}