/*
Copyright 2020 The Kubernetes 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 v1alpha1

import (
	"time"

	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"

	configv1alpha1 "k8s.io/component-base/config/v1alpha1"
)

// ControllerManagerConfigurationSpec defines the desired state of GenericControllerManagerConfiguration
type ControllerManagerConfigurationSpec struct {
	// SyncPeriod determines the minimum frequency at which watched resources are
	// reconciled. A lower period will correct entropy more quickly, but reduce
	// responsiveness to change if there are many watched resources. Change this
	// value only if you know what you are doing. Defaults to 10 hours if unset.
	// there will a 10 percent jitter between the SyncPeriod of all controllers
	// so that all controllers will not send list requests simultaneously.
	// +optional
	SyncPeriod *metav1.Duration `json:"syncPeriod,omitempty"`

	// LeaderElection is the LeaderElection config to be used when configuring
	// the manager.Manager leader election
	// +optional
	LeaderElection *configv1alpha1.LeaderElectionConfiguration `json:"leaderElection,omitempty"`

	// CacheNamespace if specified restricts the manager's cache to watch objects in
	// the desired namespace Defaults to all namespaces
	//
	// Note: If a namespace is specified, controllers can still Watch for a
	// cluster-scoped resource (e.g Node).  For namespaced resources the cache
	// will only hold objects from the desired namespace.
	// +optional
	CacheNamespace string `json:"cacheNamespace,omitempty"`

	// GracefulShutdownTimeout is the duration given to runnable to stop before the manager actually returns on stop.
	// To disable graceful shutdown, set to time.Duration(0)
	// To use graceful shutdown without timeout, set to a negative duration, e.G. time.Duration(-1)
	// The graceful shutdown is skipped for safety reasons in case the leader election lease is lost.
	GracefulShutdownTimeout *metav1.Duration `json:"gracefulShutDown,omitempty"`

	// Controller contains global configuration options for controllers
	// registered within this manager.
	// +optional
	Controller *ControllerConfigurationSpec `json:"controller,omitempty"`

	// Metrics contains thw controller metrics configuration
	// +optional
	Metrics ControllerMetrics `json:"metrics,omitempty"`

	// Health contains the controller health configuration
	// +optional
	Health ControllerHealth `json:"health,omitempty"`

	// Webhook contains the controllers webhook configuration
	// +optional
	Webhook ControllerWebhook `json:"webhook,omitempty"`
}

// ControllerConfigurationSpec defines the global configuration for
// controllers registered with the manager.
type ControllerConfigurationSpec struct {
	// GroupKindConcurrency is a map from a Kind to the number of concurrent reconciliation
	// allowed for that controller.
	//
	// When a controller is registered within this manager using the builder utilities,
	// users have to specify the type the controller reconciles in the For(...) call.
	// If the object's kind passed matches one of the keys in this map, the concurrency
	// for that controller is set to the number specified.
	//
	// The key is expected to be consistent in form with GroupKind.String(),
	// e.g. ReplicaSet in apps group (regardless of version) would be `ReplicaSet.apps`.
	//
	// +optional
	GroupKindConcurrency map[string]int `json:"groupKindConcurrency,omitempty"`

	// CacheSyncTimeout refers to the time limit set to wait for syncing caches.
	// Defaults to 2 minutes if not set.
	// +optional
	CacheSyncTimeout *time.Duration `json:"cacheSyncTimeout,omitempty"`
}

// ControllerMetrics defines the metrics configs
type ControllerMetrics struct {
	// BindAddress is the TCP address that the controller should bind to
	// for serving prometheus metrics.
	// It can be set to "0" to disable the metrics serving.
	// +optional
	BindAddress string `json:"bindAddress,omitempty"`
}

// ControllerHealth defines the health configs
type ControllerHealth struct {
	// HealthProbeBindAddress is the TCP address that the controller should bind to
	// for serving health probes
	// +optional
	HealthProbeBindAddress string `json:"healthProbeBindAddress,omitempty"`

	// ReadinessEndpointName, defaults to "readyz"
	// +optional
	ReadinessEndpointName string `json:"readinessEndpointName,omitempty"`

	// LivenessEndpointName, defaults to "healthz"
	// +optional
	LivenessEndpointName string `json:"livenessEndpointName,omitempty"`
}

// ControllerWebhook defines the webhook server for the controller
type ControllerWebhook struct {
	// Port is the port that the webhook server serves at.
	// It is used to set webhook.Server.Port.
	// +optional
	Port *int `json:"port,omitempty"`

	// Host is the hostname that the webhook server binds to.
	// It is used to set webhook.Server.Host.
	// +optional
	Host string `json:"host,omitempty"`

	// CertDir is the directory that contains the server key and certificate.
	// if not set, webhook server would look up the server key and certificate in
	// {TempDir}/k8s-webhook-server/serving-certs. The server key and certificate
	// must be named tls.key and tls.crt, respectively.
	// +optional
	CertDir string `json:"certDir,omitempty"`
}

// +kubebuilder:object:root=true

// ControllerManagerConfiguration is the Schema for the GenericControllerManagerConfigurations API
type ControllerManagerConfiguration struct {
	metav1.TypeMeta `json:",inline"`

	// ControllerManagerConfiguration returns the contfigurations for controllers
	ControllerManagerConfigurationSpec `json:",inline"`
}

// Complete returns the configuration for controller-runtime
func (c *ControllerManagerConfigurationSpec) Complete() (ControllerManagerConfigurationSpec, error) {
	return *c, nil
}
