// Copyright 2019 Yunion
//
// 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 tasks

import (
	"context"
	"fmt"
	"strconv"

	"yunion.io/x/jsonutils"

	"yunion.io/x/onecloud/pkg/apis/compute"
	"yunion.io/x/onecloud/pkg/cloudcommon/db"
	"yunion.io/x/onecloud/pkg/cloudcommon/db/lockman"
	"yunion.io/x/onecloud/pkg/cloudcommon/db/quotas"
	"yunion.io/x/onecloud/pkg/cloudcommon/db/taskman"
	"yunion.io/x/onecloud/pkg/cloudcommon/notifyclient"
	"yunion.io/x/onecloud/pkg/compute/models"
	"yunion.io/x/onecloud/pkg/util/logclient"
	"yunion.io/x/onecloud/pkg/util/rand"
)

type InstanceSnapshotCreateTask struct {
	taskman.STask
}

func init() {
	taskman.RegisterTask(InstanceSnapshotCreateTask{})
}

func (self *InstanceSnapshotCreateTask) SetStageFailed(ctx context.Context, reason string) {
	self.finalReleasePendingUsage(ctx)
	self.STask.SetStageFailed(ctx, reason)
}

func (self *InstanceSnapshotCreateTask) finalReleasePendingUsage(ctx context.Context) {
	pendingUsage := models.SRegionQuota{}
	err := self.GetPendingUsage(&pendingUsage, 0)
	if err == nil && !pendingUsage.IsEmpty() {
		quotas.CancelPendingUsage(ctx, self.UserCred, &pendingUsage, &pendingUsage, false) // final cleanup
	}
}

func (self *InstanceSnapshotCreateTask) taskFail(
	ctx context.Context, isp *models.SInstanceSnapshot, guest *models.SGuest, reason string) {

	if guest == nil {
		guest = models.GuestManager.FetchGuestById(isp.GuestId)
	}
	isp.SetStatus(self.UserCred, compute.INSTANCE_SNAPSHOT_FAILED, reason)
	guest.SetStatus(self.UserCred, compute.VM_INSTANCE_SNAPSHOT_FAILED, reason)

	db.OpsLog.LogEvent(isp, db.ACT_ALLOCATE_FAIL, reason, self.UserCred)
	logclient.AddActionLogWithStartable(self, isp, logclient.ACT_CREATE, reason, self.UserCred, false)
	notifyclient.NotifySystemError(isp.GetId(), isp.Name, compute.INSTANCE_SNAPSHOT_FAILED, reason)
	self.SetStageFailed(ctx, reason)
}

func (self *InstanceSnapshotCreateTask) taskComplete(
	ctx context.Context, isp *models.SInstanceSnapshot, guest *models.SGuest, data jsonutils.JSONObject) {

	self.finalReleasePendingUsage(ctx)
	if guest == nil {
		guest = models.GuestManager.FetchGuestById(isp.GuestId)
	}
	isp.SetStatus(self.UserCred, compute.INSTANCE_SNAPSHOT_READY, "")
	guest.StartSyncstatus(ctx, self.UserCred, "")

	db.OpsLog.LogEvent(isp, db.ACT_ALLOCATE, "instance snapshot create success", self.UserCred)
	logclient.AddActionLogWithStartable(self, isp, logclient.ACT_CREATE, "", self.UserCred, true)
	self.SetStageComplete(ctx, nil)
}

func (self *InstanceSnapshotCreateTask) OnInit(
	ctx context.Context, obj db.IStandaloneModel, data jsonutils.JSONObject) {

	isp := obj.(*models.SInstanceSnapshot)
	guest := models.GuestManager.FetchGuestById(isp.GuestId)

	self.GuestDiskCreateSnapshot(ctx, isp, guest, 0)
}

func (self *InstanceSnapshotCreateTask) GuestDiskCreateSnapshot(
	ctx context.Context, isp *models.SInstanceSnapshot, guest *models.SGuest, diskIndex int) {

	disks := guest.GetDisks()
	if diskIndex >= len(disks) {
		self.taskComplete(ctx, isp, guest, nil)
		return
	}

	lockman.LockClass(ctx, models.SnapshotManager, self.UserCred.GetProjectId())
	defer lockman.ReleaseClass(ctx, models.SnapshotManager, self.UserCred.GetProjectId())

	snapshotName, err := db.GenerateName(models.SnapshotManager, self.UserCred,
		fmt.Sprintf("%s-%s", isp.Name, rand.String(8)))
	if err != nil {
		self.taskFail(ctx, isp, guest, fmt.Sprintf("Generate snapshot name %s", err))
		return
	}

	snapshot, err := models.SnapshotManager.CreateSnapshot(
		ctx, self.UserCred, compute.SNAPSHOT_MANUAL, disks[diskIndex].DiskId,
		guest.Id, "", snapshotName, -1)
	if err != nil {
		self.taskFail(ctx, isp, guest, err.Error())
		return
	}

	err = models.InstanceSnapshotJointManager.CreateJoint(isp.Id, snapshot.Id, int8(diskIndex))
	if err != nil {
		self.taskFail(ctx, isp, guest, err.Error())
		return
	}

	params := jsonutils.NewDict()
	params.Set("disk_index", jsonutils.NewInt(int64(diskIndex)))
	params.Set(strconv.Itoa(diskIndex), jsonutils.NewString(snapshot.Id))
	self.SetStage("OnDiskSnapshot", params)

	if err := snapshot.StartSnapshotCreateTask(ctx, self.UserCred, nil, self.Id); err != nil {
		self.taskFail(ctx, isp, guest, err.Error())
		return
	}
}

func (self *InstanceSnapshotCreateTask) OnDiskSnapshot(
	ctx context.Context, isp *models.SInstanceSnapshot, data jsonutils.JSONObject) {

	guest := models.GuestManager.FetchGuestById(isp.GuestId)

	diskIndex, err := self.Params.Int("disk_index")
	if err != nil {
		self.taskFail(ctx, isp, guest, err.Error())
		return
	}

	self.GuestDiskCreateSnapshot(ctx, isp, guest, int(diskIndex+1))
}

func (self *InstanceSnapshotCreateTask) OnDiskSnapshotFailed(
	ctx context.Context, isp *models.SInstanceSnapshot, data jsonutils.JSONObject) {
	self.taskFail(ctx, isp, nil, data.String())
}