package phases

import (
	"context"
	"errors"
	"net/http"

	"github.com/databricks/cli/bundle"
	"github.com/databricks/cli/bundle/deploy/files"
	"github.com/databricks/cli/bundle/deploy/lock"
	"github.com/databricks/cli/bundle/deploy/terraform"

	"github.com/databricks/cli/libs/cmdio"
	"github.com/databricks/cli/libs/diag"

	"github.com/databricks/cli/libs/log"
	terraformlib "github.com/databricks/cli/libs/terraform"
	"github.com/databricks/databricks-sdk-go/apierr"
)

func assertRootPathExists(ctx context.Context, b *bundle.Bundle) (bool, error) {
	w := b.WorkspaceClient()
	_, err := w.Workspace.GetStatusByPath(ctx, b.Config.Workspace.RootPath)

	var aerr *apierr.APIError
	if errors.As(err, &aerr) && aerr.StatusCode == http.StatusNotFound {
		log.Infof(ctx, "Root path does not exist: %s", b.Config.Workspace.RootPath)
		return false, nil
	}

	return true, err
}

func approvalForDestroy(ctx context.Context, b *bundle.Bundle) (bool, error) {
	tf := b.Terraform
	if tf == nil {
		return false, errors.New("terraform not initialized")
	}

	// read plan file
	plan, err := tf.ShowPlanFile(ctx, b.Plan.Path)
	if err != nil {
		return false, err
	}

	deleteActions := make([]terraformlib.Action, 0)
	for _, rc := range plan.ResourceChanges {
		if rc.Change.Actions.Delete() {
			deleteActions = append(deleteActions, terraformlib.Action{
				Action:       terraformlib.ActionTypeDelete,
				ResourceType: rc.Type,
				ResourceName: rc.Name,
			})
		}
	}

	if len(deleteActions) > 0 {
		cmdio.LogString(ctx, "The following resources will be deleted:")
		for _, a := range deleteActions {
			cmdio.Log(ctx, a)
		}
		cmdio.LogString(ctx, "")

	}

	cmdio.LogString(ctx, "All files and directories at the following location will be deleted: "+b.Config.Workspace.RootPath)
	cmdio.LogString(ctx, "")

	if b.AutoApprove {
		return true, nil
	}

	approved, err := cmdio.AskYesOrNo(ctx, "Would you like to proceed?")
	if err != nil {
		return false, err
	}

	return approved, nil
}

func destroyCore(ctx context.Context, b *bundle.Bundle) diag.Diagnostics {
	// Core destructive mutators for destroy. These require informed user consent.
	diags := bundle.ApplySeq(ctx, b,
		terraform.Apply(),
		files.Delete(),
	)

	if !diags.HasError() {
		cmdio.LogString(ctx, "Destroy complete!")
	}

	return diags
}

// The destroy phase deletes artifacts and resources.
func Destroy(ctx context.Context, b *bundle.Bundle) (diags diag.Diagnostics) {
	log.Info(ctx, "Phase: destroy")

	ok, err := assertRootPathExists(ctx, b)
	if err != nil {
		return diag.FromErr(err)
	}

	if !ok {
		cmdio.LogString(ctx, "No active deployment found to destroy!")
		return diags
	}

	diags = diags.Extend(bundle.Apply(ctx, b, lock.Acquire()))
	if diags.HasError() {
		return diags
	}

	defer func() {
		diags = diags.Extend(bundle.Apply(ctx, b, lock.Release(lock.GoalDestroy)))
	}()

	diags = diags.Extend(bundle.ApplySeq(ctx, b,
		terraform.StatePull(),
		terraform.Interpolate(),
		terraform.Write(),
		terraform.Plan(terraform.PlanGoal("destroy")),
	))

	if diags.HasError() {
		return diags
	}

	hasApproval, err := approvalForDestroy(ctx, b)
	if err != nil {
		diags = diags.Extend(diag.FromErr(err))
		return diags
	}

	if hasApproval {
		diags = diags.Extend(destroyCore(ctx, b))
	} else {
		cmdio.LogString(ctx, "Destroy cancelled!")
	}

	return diags
}