You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: jwks.go
    path of file: ./repos/minio/internal/config/identity/openid
    
    the code of the file until where you have to start completion: // Copyright (c) 2015-2021 MinIO, Inc.
//
// This file is part of MinIO Object Storage stack
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
/
    
func (key *JWKS) DecodePublicKey() (crypto.PublicKey, error) {
	switch key.Kty {
	case "RSA":
		if key.N == "" || key.E == "" {
			return nil, errMalformedJWKRSAKey
		}

		// decode exponent
		ebuf, err := base64.RawURLEncoding.DecodeString(key.E)
		if err != nil {
			return nil, errMalformedJWKRSAKey
		}

		nbuf, err := base64.RawURLEncoding.DecodeString(key.N)
		if err != nil {
			return nil, errMalformedJWKRSAKey
		}

		var n, e big.Int
		n.SetBytes(nbuf)
		e.SetBytes(ebuf)

		return &rsa.PublicKey{
			E: int(e.Int64()),
			N: &n,
		}, nil
	case "EC":
		if key.Crv == "" || key.X == "" || key.Y == "" {
			return nil, errMalformedJWKECKey
		}

		var curve elliptic.Curve
		switch key.Crv {
		case "P-224":
			curve = elliptic.P224()
		case "P-256":
			curve = elliptic.P256()
		case "P-384":
			curve = elliptic.P384()
		case "P-521":
			curve = elliptic.P521()
		default:
			return nil, fmt.Errorf("Unknown curve type: %s", key.Crv)
		}

		xbuf, err := base64.RawURLEncoding.DecodeString(key.X)
		if err != nil {
			return nil, errMalformedJWKECKey
		}

		ybuf, err := base64.RawURLEncoding.DecodeString(key.Y)
		if err != nil {
			return nil, errMalformedJWKECKey
		}

		var x, y big.Int
		x.SetBytes(xbuf)
		y.SetBytes(ybuf)

		return &ecdsa.PublicKey{
			Curve: curve,
			X:     &x,
			Y:     &y,
		}, nil
	default:
		return nil, fmt.Errorf("Unknown JWK key type %s", key.Kty)
	}
}