/*
 * Copyright 2021 PingCAP, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package cert

import (
	"crypto/tls"
	"fmt"
	"path"

	"go.etcd.io/etcd/pkg/transport"

	"github.com/pingcap/mimir/util"
)

// LoadClientCert load client.pem, client-key.pem and ca.pem from specified directory
func LoadClientCert(dir string) (*tls.Config, error) {
	caFile := path.Join(dir, "ca.pem")
	certFile := path.Join(dir, "client.pem")
	keyFile := path.Join(dir, "client-key.pem")

	for _, file := range []string{caFile, certFile, keyFile} {
		if util.IsNotExist(file) {
			return nil, fmt.Errorf("file %s not exist", file)
		}
	}

	return transport.TLSInfo{
		TrustedCAFile: caFile,
		CertFile:      certFile,
		KeyFile:       keyFile,
	}.ClientConfig()
}