// Copyright (c) 2019 Tigera, Inc. All rights reserved.

// 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 internalapi

import (
	apiv3 "github.com/projectcalico/api/pkg/apis/projectcalico/v3"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
)

const (
	// For historical reasons, crd.projectcalico.org/v1 internal API uses IPAMConfig as the kind for the backing CRD, as well
	// as for the clientv3 API, whereas the projectcalico.org/v3 API uses IPAMConfiguration.
	KindIPAMConfig     = "IPAMConfig"
	KindIPAMConfigList = "IPAMConfigList"
)

// VMAddressPersistence controls whether KubeVirt VirtualMachine workloads
// maintain persistent IP addresses across VM lifecycle events.
type VMAddressPersistence string

const (
	// VMAddressPersistenceEnabled enables IP persistence for KubeVirt VMs.
	VMAddressPersistenceEnabled VMAddressPersistence = "Enabled"
	// VMAddressPersistenceDisabled disables IP persistence for KubeVirt VMs.
	VMAddressPersistenceDisabled VMAddressPersistence = "Disabled"
)

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

// IPAMConfig contains information about a block for IP address assignment.
type IPAMConfig struct {
	metav1.TypeMeta `json:",inline"`

	// Standard object's metadata.
	metav1.ObjectMeta `json:"metadata,omitempty"`

	// Specification of the IPAMConfig.
	Spec IPAMConfigSpec `json:"spec,omitempty"`
}

// IPAMConfigSpec contains the specification for an IPAMConfig resource.
type IPAMConfigSpec struct {
	StrictAffinity     bool `json:"strictAffinity"`
	AutoAllocateBlocks bool `json:"autoAllocateBlocks"`

	// MaxBlocksPerHost, if non-zero, is the max number of blocks that can be
	// affine to each host.
	// +kubebuilder:validation:Minimum:=0
	// +kubebuilder:validation:Maximum:=2147483647
	// +optional
	MaxBlocksPerHost int `json:"maxBlocksPerHost,omitempty"`

	// KubeVirtVMAddressPersistence controls whether KubeVirt VirtualMachine workloads
	// maintain persistent IP addresses across VM lifecycle events.
	// When set to VMAddressPersistenceEnabled, Calico automatically ensures that KubeVirt VMs retain their
	// IP addresses when their underlying pods are recreated during VM operations such as
	// reboot, live migration, or pod eviction. IP persistency is ensured when the
	// VirtualMachineInstance (VMI) resource is deleted and recreated by the VM controller.
	// When set to VMAddressPersistenceDisabled, VMs receive new IP addresses whenever their pods are recreated,
	// following standard pod IP allocation behavior. Live migration target pods are not allowed
	// when this is set to VMAddressPersistenceDisabled and will result in an error.
	// If nil, defaults to VMAddressPersistenceEnabled (IP persistence enabled if not specified).
	// +kubebuilder:validation:Enum=Enabled;Disabled
	// +optional
	KubeVirtVMAddressPersistence *VMAddressPersistence `json:"kubeVirtVMAddressPersistence,omitempty"`

	// IPCooldownSeconds is the minimum age of a released IP in a block before it is re-used.
	// If set to zero, IPs can be re-used immediately (but are still handled with a FIFO queue to
	// minimize immediate reuse).
	// +kubebuilder:validation:Minimum:=0
	// +kubebuilder:validation:Maximum:=1200
	// +optional
	IPCooldownSeconds int `json:"ipCooldownSeconds,omitempty"`
}

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

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

// NewIPAMConfig creates a new (zeroed) IPAMConfig struct with the TypeMetadata initialised to the current
// version.
func NewIPAMConfig() *IPAMConfig {
	return &IPAMConfig{
		TypeMeta: metav1.TypeMeta{
			Kind:       KindIPAMConfig,
			APIVersion: apiv3.GroupVersionCurrent,
		},
	}
}

// NewIPAMConfigList creates a new (zeroed) IPAMConfigList struct with the TypeMetadata initialised to the current
// version.
func NewIPAMConfigList() *IPAMConfigList {
	return &IPAMConfigList{
		TypeMeta: metav1.TypeMeta{
			Kind:       KindIPAMConfigList,
			APIVersion: apiv3.GroupVersionCurrent,
		},
	}
}