/*
Copyright 2016 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 batch

import (
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/types"
	api "k8s.io/kubernetes/pkg/apis/core"
)

// JobTrackingFinalizer is a finalizer for Job's pods. It prevents them from
// being deleted before being accounted in the Job status.
// The apiserver and job controller use this string as a Job annotation, to
// mark Jobs that are being tracked using pod finalizers. Two releases after
// the JobTrackingWithFinalizers graduates to GA, JobTrackingFinalizer will
// no longer be used as a Job annotation.
const JobTrackingFinalizer = "batch.kubernetes.io/job-tracking"

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

// Job represents the configuration of a single job.
type Job struct {
	metav1.TypeMeta
	// Standard object's metadata.
	// More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata
	// +optional
	metav1.ObjectMeta

	// Specification of the desired behavior of a job.
	// More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#spec-and-status
	// +optional
	Spec JobSpec

	// Current status of a job.
	// More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#spec-and-status
	// +optional
	Status JobStatus
}

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

// JobList is a collection of jobs.
type JobList struct {
	metav1.TypeMeta
	// Standard list metadata.
	// More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata
	// +optional
	metav1.ListMeta

	// items is the list of Jobs.
	Items []Job
}

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

// JobTemplate describes a template for creating copies of a predefined pod.
type JobTemplate struct {
	metav1.TypeMeta
	// Standard object's metadata.
	// More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata
	// +optional
	metav1.ObjectMeta

	// Defines jobs that will be created from this template.
	// https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#spec-and-status
	// +optional
	Template JobTemplateSpec
}

// JobTemplateSpec describes the data a Job should have when created from a template
type JobTemplateSpec struct {
	// Standard object's metadata of the jobs created from this template.
	// More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata
	// +optional
	metav1.ObjectMeta

	// Specification of the desired behavior of the job.
	// More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#spec-and-status
	// +optional
	Spec JobSpec
}

// CompletionMode specifies how Pod completions of a Job are tracked.
type CompletionMode string

const (
	// NonIndexedCompletion is a Job completion mode. In this mode, the Job is
	// considered complete when there have been .spec.completions
	// successfully completed Pods. Pod completions are homologous to each other.
	NonIndexedCompletion CompletionMode = "NonIndexed"

	// IndexedCompletion is a Job completion mode. In this mode, the Pods of a
	// Job get an associated completion index from 0 to (.spec.completions - 1).
	// The Job is  considered complete when a Pod completes for each completion
	// index.
	IndexedCompletion CompletionMode = "Indexed"
)

// JobSpec describes how the job execution will look like.
type JobSpec struct {

	// Specifies the maximum desired number of pods the job should
	// run at any given time. The actual number of pods running in steady state will
	// be less than this number when ((.spec.completions - .status.successful) < .spec.parallelism),
	// i.e. when the work left to do is less than max parallelism.
	// +optional
	Parallelism *int32

	// Specifies the desired number of successfully finished pods the
	// job should be run with.  Setting to nil means that the success of any
	// pod signals the success of all pods, and allows parallelism to have any positive
	// value.  Setting to 1 means that parallelism is limited to 1 and the success of that
	// pod signals the success of the job.
	// +optional
	Completions *int32

	// Specifies the duration in seconds relative to the startTime that the job
	// may be continuously active before the system tries to terminate it; value
	// must be positive integer. If a Job is suspended (at creation or through an
	// update), this timer will effectively be stopped and reset when the Job is
	// resumed again.
	// +optional
	ActiveDeadlineSeconds *int64

	// Optional number of retries before marking this job failed.
	// Defaults to 6
	// +optional
	BackoffLimit *int32

	// TODO enabled it when https://github.com/kubernetes/kubernetes/issues/28486 has been fixed
	// Optional number of failed pods to retain.
	// +optional
	// FailedPodsLimit *int32

	// A label query over pods that should match the pod count.
	// Normally, the system sets this field for you.
	// +optional
	Selector *metav1.LabelSelector

	// manualSelector controls generation of pod labels and pod selectors.
	// Leave `manualSelector` unset unless you are certain what you are doing.
	// When false or unset, the system pick labels unique to this job
	// and appends those labels to the pod template.  When true,
	// the user is responsible for picking unique labels and specifying
	// the selector.  Failure to pick a unique label may cause this
	// and other jobs to not function correctly.  However, You may see
	// `manualSelector=true` in jobs that were created with the old `extensions/v1beta1`
	// API.
	// +optional
	ManualSelector *bool

	// Describes the pod that will be created when executing a job.
	Template api.PodTemplateSpec

	// ttlSecondsAfterFinished limits the lifetime of a Job that has finished
	// execution (either Complete or Failed). If this field is set,
	// ttlSecondsAfterFinished after the Job finishes, it is eligible to be
	// automatically deleted. When the Job is being deleted, its lifecycle
	// guarantees (e.g. finalizers) will be honored. If this field is unset,
	// the Job won't be automatically deleted. If this field is set to zero,
	// the Job becomes eligible to be deleted immediately after it finishes.
	// This field is alpha-level and is only honored by servers that enable the
	// TTLAfterFinished feature.
	// +optional
	TTLSecondsAfterFinished *int32

	// CompletionMode specifies how Pod completions are tracked. It can be
	// `NonIndexed` (default) or `Indexed`.
	//
	// `NonIndexed` means that the Job is considered complete when there have
	// been .spec.completions successfully completed Pods. Each Pod completion is
	// homologous to each other.
	//
	// `Indexed` means that the Pods of a
	// Job get an associated completion index from 0 to (.spec.completions - 1),
	// available in the annotation batch.kubernetes.io/job-completion-index.
	// The Job is considered complete when there is one successfully completed Pod
	// for each index.
	// When value is `Indexed`, .spec.completions must be specified and
	// `.spec.parallelism` must be less than or equal to 10^5.
	// In addition, The Pod name takes the form
	// `$(job-name)-$(index)-$(random-string)`,
	// the Pod hostname takes the form `$(job-name)-$(index)`.
	//
	// This field is beta-level. More completion modes can be added in the future.
	// If the Job controller observes a mode that it doesn't recognize, the
	// controller skips updates for the Job.
	// +optional
	CompletionMode *CompletionMode

	// Suspend specifies whether the Job controller should create Pods or not. If
	// a Job is created with suspend set to true, no Pods are created by the Job
	// controller. If a Job is suspended after creation (i.e. the flag goes from
	// false to true), the Job controller will delete all active Pods associated
	// with this Job. Users must design their workload to gracefully handle this.
	// Suspending a Job will reset the StartTime field of the Job, effectively
	// resetting the ActiveDeadlineSeconds timer too. Defaults to false.
	//
	// This field is beta-level, gated by SuspendJob feature flag (enabled by
	// default).
	//
	// +optional
	Suspend *bool
}

// JobStatus represents the current state of a Job.
type JobStatus struct {

	// The latest available observations of an object's current state. When a Job
	// fails, one of the conditions will have type "Failed" and status true. When
	// a Job is suspended, one of the conditions will have type "Suspended" and
	// status true; when the Job is resumed, the status of this condition will
	// become false. When a Job is completed, one of the conditions will have
	// type "Complete" and status true.
	// +optional
	Conditions []JobCondition

	// Represents time when the job controller started processing a job. When a
	// Job is created in the suspended state, this field is not set until the
	// first time it is resumed. This field is reset every time a Job is resumed
	// from suspension. It is represented in RFC3339 form and is in UTC.
	// +optional
	StartTime *metav1.Time

	// Represents time when the job was completed. It is not guaranteed to
	// be set in happens-before order across separate operations.
	// It is represented in RFC3339 form and is in UTC.
	// The completion time is only set when the job finishes successfully.
	// +optional
	CompletionTime *metav1.Time

	// The number of actively running pods.
	// +optional
	Active int32

	// The number of pods which reached phase Succeeded.
	// +optional
	Succeeded int32

	// The number of pods which reached phase Failed.
	// +optional
	Failed int32

	// CompletedIndexes holds the completed indexes when .spec.completionMode =
	// "Indexed" in a text format. The indexes are represented as decimal integers
	// separated by commas. The numbers are listed in increasing order. Three or
	// more consecutive numbers are compressed and represented by the first and
	// last element of the series, separated by a hyphen.
	// For example, if the completed indexes are 1, 3, 4, 5 and 7, they are
	// represented as "1,3-5,7".
	// +optional
	CompletedIndexes string

	// UncountedTerminatedPods holds the UIDs of Pods that have terminated but
	// the job controller hasn't yet accounted for in the status counters.
	//
	// The job controller creates pods with a finalizer. When a pod terminates
	// (succeeded or failed), the controller does three steps to account for it
	// in the job status:
	// (1) Add the pod UID to the corresponding array in this field.
	// (2) Remove the pod finalizer.
	// (3) Remove the pod UID from the array while increasing the corresponding
	//     counter.
	//
	// This field is alpha-level. The job controller only makes use of this field
	// when the feature gate PodTrackingWithFinalizers is enabled.
	// Old jobs might not be tracked using this field, in which case the field
	// remains null.
	// +optional
	UncountedTerminatedPods *UncountedTerminatedPods
}

// UncountedTerminatedPods holds UIDs of Pods that have terminated but haven't
// been accounted in Job status counters.
type UncountedTerminatedPods struct {
	// Succeeded holds UIDs of succeeded Pods.
	// +listType=set
	// +optional
	Succeeded []types.UID

	// Failed holds UIDs of failed Pods.
	// +listType=set
	// +optional
	Failed []types.UID
}

// JobConditionType is a valid value for JobCondition.Type
type JobConditionType string

// These are valid conditions of a job.
const (
	// JobSuspended means the job has been suspended.
	JobSuspended JobConditionType = "Suspended"
	// JobComplete means the job has completed its execution.
	JobComplete JobConditionType = "Complete"
	// JobFailed means the job has failed its execution.
	JobFailed JobConditionType = "Failed"
)

// JobCondition describes current state of a job.
type JobCondition struct {
	// Type of job condition.
	Type JobConditionType
	// Status of the condition, one of True, False, Unknown.
	Status api.ConditionStatus
	// Last time the condition was checked.
	// +optional
	LastProbeTime metav1.Time
	// Last time the condition transit from one status to another.
	// +optional
	LastTransitionTime metav1.Time
	// (brief) reason for the condition's last transition.
	// +optional
	Reason string
	// Human readable message indicating details about last transition.
	// +optional
	Message string
}

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

// CronJob represents the configuration of a single cron job.
type CronJob struct {
	metav1.TypeMeta
	// Standard object's metadata.
	// More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata
	// +optional
	metav1.ObjectMeta

	// Specification of the desired behavior of a cron job, including the schedule.
	// More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#spec-and-status
	// +optional
	Spec CronJobSpec

	// Current status of a cron job.
	// More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#spec-and-status
	// +optional
	Status CronJobStatus
}

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

// CronJobList is a collection of cron jobs.
type CronJobList struct {
	metav1.TypeMeta
	// Standard list metadata.
	// More info: https://git.k8s.io/community/contributors/devel/sig-architecture/api-conventions.md#metadata
	// +optional
	metav1.ListMeta

	// items is the list of CronJobs.
	Items []CronJob
}

// CronJobSpec describes how the job execution will look like and when it will actually run.
type CronJobSpec struct {

	// The schedule in Cron format, see https://en.wikipedia.org/wiki/Cron.
	Schedule string

	// Optional deadline in seconds for starting the job if it misses scheduled
	// time for any reason.  Missed jobs executions will be counted as failed ones.
	// +optional
	StartingDeadlineSeconds *int64

	// Specifies how to treat concurrent executions of a Job.
	// Valid values are:
	// - "Allow" (default): allows CronJobs to run concurrently;
	// - "Forbid": forbids concurrent runs, skipping next run if previous run hasn't finished yet;
	// - "Replace": cancels currently running job and replaces it with a new one
	// +optional
	ConcurrencyPolicy ConcurrencyPolicy

	// This flag tells the controller to suspend subsequent executions, it does
	// not apply to already started executions. Defaults to false.
	// +optional
	Suspend *bool

	// Specifies the job that will be created when executing a CronJob.
	JobTemplate JobTemplateSpec

	// The number of successful finished jobs to retain.
	// This is a pointer to distinguish between explicit zero and not specified.
	// +optional
	SuccessfulJobsHistoryLimit *int32

	// The number of failed finished jobs to retain.
	// This is a pointer to distinguish between explicit zero and not specified.
	// +optional
	FailedJobsHistoryLimit *int32
}

// ConcurrencyPolicy describes how the job will be handled.
// Only one of the following concurrent policies may be specified.
// If none of the following policies is specified, the default one
// is AllowConcurrent.
type ConcurrencyPolicy string

const (
	// AllowConcurrent allows CronJobs to run concurrently.
	AllowConcurrent ConcurrencyPolicy = "Allow"

	// ForbidConcurrent forbids concurrent runs, skipping next run if previous
	// hasn't finished yet.
	ForbidConcurrent ConcurrencyPolicy = "Forbid"

	// ReplaceConcurrent cancels currently running job and replaces it with a new one.
	ReplaceConcurrent ConcurrencyPolicy = "Replace"
)

// CronJobStatus represents the current state of a cron job.
type CronJobStatus struct {
	// A list of pointers to currently running jobs.
	// +optional
	Active []api.ObjectReference

	// Information when was the last time the job was successfully scheduled.
	// +optional
	LastScheduleTime *metav1.Time

	// Information when was the last time the job successfully completed.
	// +optional
	LastSuccessfulTime *metav1.Time
}
