// Copyright (c) 2019 The Jaeger Authors.
//
// 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,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package auth

import (
	"github.com/Shopify/sarama"
)

// KerberosConfig describes the configuration properties needed for Kerberos authentication with kafka consumer
type KerberosConfig struct {
	ServiceName string `mapstructure:"service_name"`
	Realm       string `mapstructure:"realm"`
	UseKeyTab   bool   `mapstructure:"use_keytab"`
	Username    string `mapstructure:"username"`
	Password    string `mapstructure:"password" json:"-"`
	ConfigPath  string `mapstructure:"config_file"`
	KeyTabPath  string `mapstructure:"keytab_file"`
}

func setKerberosConfiguration(config *KerberosConfig, saramaConfig *sarama.Config) {
	saramaConfig.Net.SASL.Mechanism = sarama.SASLTypeGSSAPI
	saramaConfig.Net.SASL.Enable = true
	if config.UseKeyTab {
		saramaConfig.Net.SASL.GSSAPI.KeyTabPath = config.KeyTabPath
		saramaConfig.Net.SASL.GSSAPI.AuthType = sarama.KRB5_KEYTAB_AUTH
	} else {
		saramaConfig.Net.SASL.GSSAPI.AuthType = sarama.KRB5_USER_AUTH
		saramaConfig.Net.SASL.GSSAPI.Password = config.Password
	}
	saramaConfig.Net.SASL.GSSAPI.KerberosConfigPath = config.ConfigPath
	saramaConfig.Net.SASL.GSSAPI.Username = config.Username
	saramaConfig.Net.SASL.GSSAPI.Realm = config.Realm
	saramaConfig.Net.SASL.GSSAPI.ServiceName = config.ServiceName
}
