/*
Copyright 2019 The KubeSphere 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 (
	k8snet "k8s.io/api/networking/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
)

const (
	ResourceKindNamespaceNetworkPolicy     = "NamespaceNetworkPolicy"
	ResourceSingularNamespaceNetworkPolicy = "namespacenetworkpolicy"
	ResourcePluralNamespaceNetworkPolicy   = "namespacenetworkpolicies"
)

// NamespaceNetworkPolicySpec provides the specification of a NamespaceNetworkPolicy
type NamespaceNetworkPolicySpec struct {
	// List of ingress rules to be applied to the selected pods. Traffic is allowed to
	// a pod if there are no NetworkPolicies selecting the pod
	// (and cluster policy otherwise allows the traffic), OR if the traffic source is
	// the pod's local node, OR if the traffic matches at least one ingress rule
	// across all of the NetworkPolicy objects whose podSelector matches the pod. If
	// this field is empty then this NetworkPolicy does not allow any traffic (and serves
	// solely to ensure that the pods it selects are isolated by default)
	// +optional
	Ingress []NetworkPolicyIngressRule `json:"ingress,omitempty" protobuf:"bytes,1,rep,name=ingress"`

	// List of egress rules to be applied to the selected pods. Outgoing traffic is
	// allowed if there are no NetworkPolicies selecting the pod (and cluster policy
	// otherwise allows the traffic), OR if the traffic matches at least one egress rule
	// across all of the NetworkPolicy objects whose podSelector matches the pod. If
	// this field is empty then this NetworkPolicy limits all outgoing traffic (and serves
	// solely to ensure that the pods it selects are isolated by default).
	// This field is beta-level in 1.8
	// +optional
	Egress []NetworkPolicyEgressRule `json:"egress,omitempty" protobuf:"bytes,2,rep,name=egress"`

	// List of rule types that the NetworkPolicy relates to.
	// Valid options are "Ingress", "Egress", or "Ingress,Egress".
	// If this field is not specified, it will default based on the existence of Ingress or Egress rules;
	// policies that contain an Egress section are assumed to affect Egress, and all policies
	// (whether or not they contain an Ingress section) are assumed to affect Ingress.
	// If you want to write an egress-only policy, you must explicitly specify policyTypes [ "Egress" ].
	// Likewise, if you want to write a policy that specifies that no egress is allowed,
	// you must specify a policyTypes value that include "Egress" (since such a policy would not include
	// an Egress section and would otherwise default to just [ "Ingress" ]).
	// This field is beta-level in 1.8
	// +optional
	PolicyTypes []k8snet.PolicyType `json:"policyTypes,omitempty" protobuf:"bytes,3,rep,name=policyTypes,casttype=PolicyType"`
}

// NetworkPolicyIngressRule describes a particular set of traffic that is allowed to the pods
// matched by a NetworkPolicySpec's podSelector. The traffic must match both ports and from.
type NetworkPolicyIngressRule struct {
	// List of ports which should be made accessible on the pods selected for this
	// rule. Each item in this list is combined using a logical OR. If this field is
	// empty or missing, this rule matches all ports (traffic not restricted by port).
	// If this field is present and contains at least one item, then this rule allows
	// traffic only if the traffic matches at least one port in the list.
	// +optional
	Ports []k8snet.NetworkPolicyPort `json:"ports,omitempty" protobuf:"bytes,1,rep,name=ports"`

	// List of sources which should be able to access the pods selected for this rule.
	// Items in this list are combined using a logical OR operation. If this field is
	// empty or missing, this rule matches all sources (traffic not restricted by
	// source). If this field is present and contains at least one item, this rule
	// allows traffic only if the traffic matches at least one item in the from list.
	// +optional
	From []NetworkPolicyPeer `json:"from,omitempty" protobuf:"bytes,2,rep,name=from"`
}

// NetworkPolicyEgressRule describes a particular set of traffic that is allowed out of pods
// matched by a NetworkPolicySpec's podSelector. The traffic must match both ports and to.
// This type is beta-level in 1.8
type NetworkPolicyEgressRule struct {
	// List of destination ports for outgoing traffic.
	// Each item in this list is combined using a logical OR. If this field is
	// empty or missing, this rule matches all ports (traffic not restricted by port).
	// If this field is present and contains at least one item, then this rule allows
	// traffic only if the traffic matches at least one port in the list.
	// +optional
	Ports []k8snet.NetworkPolicyPort `json:"ports,omitempty" protobuf:"bytes,1,rep,name=ports"`

	// List of destinations for outgoing traffic of pods selected for this rule.
	// Items in this list are combined using a logical OR operation. If this field is
	// empty or missing, this rule matches all destinations (traffic not restricted by
	// destination). If this field is present and contains at least one item, this rule
	// allows traffic only if the traffic matches at least one item in the to list.
	// +optional
	To []NetworkPolicyPeer `json:"to,omitempty" protobuf:"bytes,2,rep,name=to"`
}

type NamespaceSelector struct {
	Name string `json:"name" protobuf:"bytes,1,name=name"`
}

type ServiceSelector struct {
	Name      string `json:"name" protobuf:"bytes,1,name=name"`
	Namespace string `json:"namespace" protobuf:"bytes,2,name=namespace"`
}

// NetworkPolicyPeer describes a peer to allow traffic from. Only certain combinations of
// fields are allowed
type NetworkPolicyPeer struct {
	// +optional
	NamespaceSelector *NamespaceSelector `json:"namespace,omitempty" protobuf:"bytes,1,opt,name=namespace"`

	// IPBlock defines policy on a particular IPBlock. If this field is set then
	// neither of the other fields can be.
	// +optional
	IPBlock *k8snet.IPBlock `json:"ipBlock,omitempty" protobuf:"bytes,2,rep,name=ipBlock"`

	ServiceSelector *ServiceSelector `json:"service,omitempty" protobuf:"bytes,3,opt,name=service"`
}

// +genclient
// +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object

// NamespaceNetworkPolicy is the Schema for the namespacenetworkpolicies API
// +k8s:openapi-gen=true
// +kubebuilder:resource:categories="networking",shortName="nsnp"
type NamespaceNetworkPolicy struct {
	metav1.TypeMeta   `json:",inline"`
	metav1.ObjectMeta `json:"metadata,omitempty"`

	Spec NamespaceNetworkPolicySpec `json:"spec,omitempty"`
}

// +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object

// NamespaceNetworkPolicyList contains a list of NamespaceNetworkPolicy
type NamespaceNetworkPolicyList struct {
	metav1.TypeMeta `json:",inline"`
	metav1.ListMeta `json:"metadata,omitempty"`
	Items           []NamespaceNetworkPolicy `json:"items"`
}

func init() {
	SchemeBuilder.Register(&NamespaceNetworkPolicy{}, &NamespaceNetworkPolicyList{})
}
