package ledis

import (
	"errors"
)

const Version = "0.4"

type DataType byte

// for out use
const (
	KV DataType = iota
	LIST
	HASH
	SET
	ZSET
)

func (d DataType) String() string {
	switch d {
	case KV:
		return KVName
	case LIST:
		return ListName
	case HASH:
		return HashName
	case SET:
		return SetName
	case ZSET:
		return ZSetName
	default:
		return "unknown"
	}
}

const (
	KVName   = "KV"
	ListName = "LIST"
	HashName = "HASH"
	SetName  = "SET"
	ZSetName = "ZSET"
)

// for backend store
const (
	NoneType   byte = 0
	KVType     byte = 1
	HashType   byte = 2
	HSizeType  byte = 3
	ListType   byte = 4
	LMetaType  byte = 5
	ZSetType   byte = 6
	ZSizeType  byte = 7
	ZScoreType byte = 8
	// BitType     byte = 9
	// BitMetaType byte = 10
	SetType   byte = 11
	SSizeType byte = 12

	maxDataType byte = 100

	/*
		I make a big mistake about TTL time key format and have to use a new one (change 101 to 103).
		You must run the ledis-upgrade-ttl to upgrade db.
	*/
	ObsoleteExpTimeType byte = 101
	ExpMetaType         byte = 102
	ExpTimeType         byte = 103

	MetaType byte = 201
)

var (
	TypeName = map[byte]string{
		KVType:     "kv",
		HashType:   "hash",
		HSizeType:  "hsize",
		ListType:   "list",
		LMetaType:  "lmeta",
		ZSetType:   "zset",
		ZSizeType:  "zsize",
		ZScoreType: "zscore",
		// BitType:     "bit",
		// BitMetaType: "bitmeta",
		SetType:     "set",
		SSizeType:   "ssize",
		ExpTimeType: "exptime",
		ExpMetaType: "expmeta",
	}
)

const (
	defaultScanCount int = 10
)

var (
	errKeySize        = errors.New("invalid key size")
	errValueSize      = errors.New("invalid value size")
	errHashFieldSize  = errors.New("invalid hash field size")
	errSetMemberSize  = errors.New("invalid set member size")
	errZSetMemberSize = errors.New("invalid zset member size")
	errExpireValue    = errors.New("invalid expire value")
)

const (
	//we don't support too many databases
	MaxDBNumber uint8 = 16

	//max key size
	MaxKeySize int = 1024

	//max hash field size
	MaxHashFieldSize int = 1024

	//max zset member size
	MaxZSetMemberSize int = 1024

	//max set member size
	MaxSetMemberSize int = 1024

	//max value size
	MaxValueSize int = 1024 * 1024 * 1024
)

var (
	ErrScoreMiss     = errors.New("zset score miss")
	ErrWriteInROnly  = errors.New("write not support in readonly mode")
	ErrRplInRDWR     = errors.New("replication not support in read write mode")
	ErrRplNotSupport = errors.New("replication not support")
)

const (
	DBAutoCommit    uint8 = 0x0
	DBInTransaction uint8 = 0x1
	DBInMulti       uint8 = 0x2
)

const (
	BitAND = "and"
	BitOR  = "or"
	BitXOR = "xor"
	BitNot = "not"
)