package hybrid

// Provider interace implement lifecycle for one sessions
type Provider interface {
	//set additional params for provider ex: sql db connection, filesystem path .. etc.
	SetParams(params any) error
	//create new session using sid value 1) in meory 2) into WAL file create new session op.
	Init(sid string) (Session, error)
	//read and return existing session by id or if not exist create new session 1) from
	//memory WAL file no need modify i no call Init from Load...
	Load(sid string) (Session, error)
	//destroy remove session with sid from storage if exist 1) in memory 2) in WAL ile
	//add destroy operation
	Destroy(sid string) error
	//regenerate id change old sid to newsid and preserve existing session data 1) in memory
	//and 2) add change id op. into WAL file
	ChangeID(oldsid, newsid string) (err error)
	//Exists return true if session with sid exist
	Exists(sid string) bool
	//gc remove all outdated sessions 1) in memory and 2) add every destroy op. into WAL
	GC(maxlifetime int64)
}

// Session interface implement storage for one session and have maxLifetime and lastAccessTime
/*
Session change WAL file (SCF) file format:

	   | OP. NUM. | SID | DATA (binary stream) | LEN |

		OP. NUM. : uint8

		0 - create new session
		1 - destroy session
		2 - change session ID
		3 - modify (create, update and delete) session key/val data

		SID:
		   - 32 bit. session ID

		DATA:
			0: --no data--
			1: --no-data--
			2: new SID
			3:
				create: key([]byte)|val([]byte)
				delete: key([]byte)
				update: key([]byte)|val([]byte)
*/
type Session interface {
	//set session value and update last access time 1) in memory and 2) add Set key op. into WAL
	Set(key, value any) error
	//get session value and update last access time 1) from memory and no need any WAL modiication
	Get(key any) (v any, err error)
	//delete session value 1) in memory and 2) add delete key op. into WAL
	Delete(key any) error
	//get session id 1) from memory and no need mod. WAL
	SessionID() string
}