// Copyright 2020 The Kubernetes Authors.
// SPDX-License-Identifier: Apache-2.0

package apply

import (
	"context"
	"fmt"
	"strings"
	"time"

	"github.com/spf13/cobra"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/cli-runtime/pkg/genericclioptions"
	cmdutil "k8s.io/kubectl/pkg/cmd/util"
	"k8s.io/kubectl/pkg/util/i18n"
	"sigs.k8s.io/cli-utils/cmd/printers"
	"sigs.k8s.io/cli-utils/pkg/apply"
	"sigs.k8s.io/cli-utils/pkg/common"
	"sigs.k8s.io/cli-utils/pkg/provider"
	"sigs.k8s.io/kustomize/kyaml/setters2"
)

func GetApplyRunner(provider provider.Provider, ioStreams genericclioptions.IOStreams) *ApplyRunner {
	r := &ApplyRunner{
		Applier:   apply.NewApplier(provider),
		ioStreams: ioStreams,
		provider:  provider,
	}
	cmd := &cobra.Command{
		Use:                   "apply (DIRECTORY | STDIN)",
		DisableFlagsInUseLine: true,
		Short:                 i18n.T("Apply a configuration to a resource by package directory or stdin"),
		RunE:                  r.RunE,
	}

	cmd.Flags().BoolVar(&r.serverSideOptions.ServerSideApply, "server-side", false,
		"If true, apply merge patch is calculated on API server instead of client.")
	cmd.Flags().BoolVar(&r.serverSideOptions.ForceConflicts, "force-conflicts", false,
		"If true, overwrite applied fields on server if field manager conflict.")
	cmd.Flags().StringVar(&r.serverSideOptions.FieldManager, "field-manager", common.DefaultFieldManager,
		"The client owner of the fields being applied on the server-side.")

	cmd.Flags().StringVar(&r.output, "output", printers.DefaultPrinter(),
		fmt.Sprintf("Output format, must be one of %s", strings.Join(printers.SupportedPrinters(), ",")))
	cmd.Flags().DurationVar(&r.period, "poll-period", 2*time.Second,
		"Polling period for resource statuses.")
	cmd.Flags().DurationVar(&r.reconcileTimeout, "reconcile-timeout", time.Duration(0),
		"Timeout threshold for waiting for all resources to reach the Current status.")
	cmd.Flags().BoolVar(&r.noPrune, "no-prune", r.noPrune,
		"If true, do not prune previously applied objects.")
	cmd.Flags().StringVar(&r.prunePropagationPolicy, "prune-propagation-policy",
		"Background", "Propagation policy for pruning")
	cmd.Flags().DurationVar(&r.pruneTimeout, "prune-timeout", time.Duration(0),
		"Timeout threshold for waiting for all pruned resources to be deleted")

	r.Command = cmd
	return r
}

func ApplyCommand(f cmdutil.Factory, ioStreams genericclioptions.IOStreams) *cobra.Command {
	provider := provider.NewProvider(f)
	return GetApplyRunner(provider, ioStreams).Command
}

type ApplyRunner struct {
	Command   *cobra.Command
	ioStreams genericclioptions.IOStreams
	Applier   *apply.Applier
	provider  provider.Provider

	serverSideOptions      common.ServerSideOptions
	output                 string
	period                 time.Duration
	reconcileTimeout       time.Duration
	noPrune                bool
	prunePropagationPolicy string
	pruneTimeout           time.Duration
}

func (r *ApplyRunner) RunE(cmd *cobra.Command, args []string) error {
	if err := setters2.CheckRequiredSettersSet(); err != nil {
		return err
	}
	prunePropPolicy, err := convertPropagationPolicy(r.prunePropagationPolicy)
	if err != nil {
		return err
	}

	// Only emit status events if we are waiting for status.
	//TODO: This is not the right way to do this. There are situations where
	// we do need status events event if we are not waiting for status. The
	// printers should be updated to handle this.
	var emitStatusEvents bool
	if r.reconcileTimeout != time.Duration(0) || r.pruneTimeout != time.Duration(0) {
		emitStatusEvents = true
	}

	// TODO: Fix DemandOneDirectory to no longer return FileNameFlags
	// since we are no longer using them.
	_, err = common.DemandOneDirectory(args)
	if err != nil {
		return err
	}
	reader, err := r.provider.ManifestReader(cmd.InOrStdin(), args)
	if err != nil {
		return err
	}
	objs, err := reader.Read()
	if err != nil {
		return err
	}

	// Run the applier. It will return a channel where we can receive updates
	// to keep track of progress and any issues.
	if err := r.Applier.Initialize(); err != nil {
		return err
	}
	ch := r.Applier.Run(context.Background(), objs, apply.Options{
		ServerSideOptions: r.serverSideOptions,
		PollInterval:      r.period,
		ReconcileTimeout:  r.reconcileTimeout,
		// If we are not waiting for status, tell the applier to not
		// emit the events.
		EmitStatusEvents:       emitStatusEvents,
		NoPrune:                r.noPrune,
		DryRunStrategy:         common.DryRunNone,
		PrunePropagationPolicy: prunePropPolicy,
		PruneTimeout:           r.pruneTimeout,
	})

	// The printer will print updates from the channel. It will block
	// until the channel is closed.
	printer := printers.GetPrinter(r.output, r.ioStreams)
	return printer.Print(ch, common.DryRunNone)
}

// convertPropagationPolicy converts a propagationPolicy described as a
// string to a DeletionPropagation type that is passed into the Applier.
func convertPropagationPolicy(propagationPolicy string) (metav1.DeletionPropagation, error) {
	switch propagationPolicy {
	case string(metav1.DeletePropagationForeground):
		return metav1.DeletePropagationForeground, nil
	case string(metav1.DeletePropagationBackground):
		return metav1.DeletePropagationBackground, nil
	case string(metav1.DeletePropagationOrphan):
		return metav1.DeletePropagationOrphan, nil
	default:
		return metav1.DeletePropagationBackground, fmt.Errorf(
			"prune propagation policy must be one of Background, Foreground, Orphan")
	}
}