package kdf

import (
	"strings"

	`r00t2.io/sshkeys/kdf/bcrypt`
	`r00t2.io/sshkeys/kdf/errs`
	`r00t2.io/sshkeys/kdf/null`
)

/*
	GetKDF returns a KDF from a name of the function.

	KDF.Setup must be called on the resulting KDF.
*/
func GetKDF(name string) (k KDF, err error) {

	switch strings.ToLower(name) {
	case bcrypt.Name:
		k = &bcrypt.KDF{}
	case null.Name, "":
		k = &null.KDF{}
	default:
		err = errs.ErrUnknownKdf
		return
	}

	return
}

/*
	UnpackKDF returns a kdf.KDF from raw data as packed in a private key's bytes.

	kdf.KDF.Setup must be called on the resulting kdf.KDF.

	data can be:

		- a []byte, which can be:
			- the full private key bytes
			- KDF section (e.g. ED25519 private key block 2.0 + (block 3.0 to block 3.0.0.1) OR
			  block 2.0.0 + (block 3.0 to block 3.0.0.1))
		- a *bytes.Buffer, which supports the same as above
*/
func UnpackKDF(data interface{}) (k KDF, err error) {

	// TODO

	return
}