package cache

import (
	"electricity_bill_calc/global"
	"time"

	"github.com/go-redis/redis/v8"
	"github.com/vmihailenco/msgpack/v5"
)

func Cache[T interface{}](key string, value *T, expires time.Duration) error {
	serializedValue, err := msgpack.Marshal(value)

	if err != nil {
		return err
	}
	cmd := global.RedisConn.SetEX(global.Ctx, key, serializedValue, expires)
	return cmd.Err()
}

func Retreive[T interface{}](key string) (*T, error) {
	result, err := global.RedisConn.Get(global.Ctx, key).Result()
	if err != nil {
		if err == redis.Nil {
			return nil, nil
		} else {
			return nil, err
		}
	}
	value := new(T)
	err = msgpack.Unmarshal([]byte(result), value)
	if err != nil {
		return nil, err
	}
	return value, nil
}

func Exists(key string) (bool, error) {
	result, err := global.RedisConn.Exists(global.Ctx, key).Result()
	if err != nil {
		return false, err
	}
	return result > 0, nil
}