/*
Copyright 2016 The Kubernetes Authors.
Copyright 2020 Authors of Arktos - file modified.

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 storagebackend

import (
	"time"

	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/apiserver/pkg/storage/value"
)

const (
	StorageTypeUnset = ""
	StorageTypeETCD3 = "etcd3"

	DefaultCompactInterval = 5 * time.Minute
)

// TransportConfig holds all connection related info,  i.e. equal TransportConfig means equal servers we talk to.
type TransportConfig struct {
	// SystemCluterServerList is the list of system storage servers to connect with.
	SystemClusterServerList []string
	// TLS credentials
	KeyFile       string
	CertFile      string
	TrustedCAFile string
}

// Config is configuration for creating a storage backend.
type Config struct {
	// Type defines the type of storage backend. Default ("") is "etcd3".
	Type string
	// Prefix is the prefix to all keys passed to storage.Interface methods.
	Prefix string
	// Transport holds all connection related info, i.e. equal TransportConfig means equal servers we talk to.
	Transport TransportConfig
	// Paging indicates whether the server implementation should allow paging (if it is
	// supported). This is generally configured by feature gating, or by a specific
	// resource type not wishing to allow paging, and is not intended for end users to
	// set.
	Paging bool

	Codec runtime.Codec
	// EncodeVersioner is the same groupVersioner used to build the
	// storage encoder. Given a list of kinds the input object might belong
	// to, the EncodeVersioner outputs the gvk the object will be
	// converted to before persisted in etcd.
	EncodeVersioner runtime.GroupVersioner
	// Transformer allows the value to be transformed prior to persisting into etcd.
	Transformer value.Transformer

	// CompactionInterval is an interval of requesting compaction from apiserver.
	// If the value is 0, no compaction will be issued.
	CompactionInterval time.Duration
	// CountMetricPollPeriod specifies how often should count metric be updated
	CountMetricPollPeriod time.Duration

	// Config file path for storage partition
	PartitionConfigFilepath string
}

func NewDefaultConfig(prefix string, codec runtime.Codec) *Config {
	return &Config{
		Paging:             true,
		Prefix:             prefix,
		Codec:              codec,
		CompactionInterval: DefaultCompactInterval,
	}
}
