package kv

import (
	"time"

	"src.dualinventive.com/go/lib/kv/ramkv"
	"src.dualinventive.com/go/lib/kv/rediskv"
)

// ErrNotFound is returned when the value is not found
var ErrNotFound = rediskv.ErrNotFound

// KV represents a interface with functions to get and set persistent data
type KV interface {
	Get(string) (string, error)
	Set(string, interface{}) error
	SetExp(string, interface{}, time.Duration) error
	Del(string) (bool, error)
	Exists(string) (bool, error)
	Keys(string) ([]string, error)
	HKeys(string) ([]string, error)
	HGet(string, string) (string, error)
	HGetAll(string) (map[string]string, error)
	HSet(string, string, interface{}) error
	HDel(string, string) error
	Close() error
}

const (
	// TypeRedis is a Redis KV-store
	TypeRedis string = "redis"
	// TypeRAM is a RAM-only KV-store
	TypeRAM string = "ram"
)

// New initializes a new KV-store
func New(t string, params ...string) (KV, error) {
	switch t {
	case TypeRedis:
		return rediskv.New(params...)
	case TypeRAM:
		return ramkv.New()
	default:
		panic("invalid KV-storage")
	}
}