/*
Copyright 2018 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 bcc

import (
	"bytes"
	"encoding/json"
	"fmt"

	"k8s.io/autoscaler/cluster-autoscaler/cloudprovider/baiducloud/baiducloud-sdk-go/bce"
	"k8s.io/autoscaler/cluster-autoscaler/cloudprovider/baiducloud/baiducloud-sdk-go/billing"
	"k8s.io/autoscaler/cluster-autoscaler/cloudprovider/baiducloud/baiducloud-sdk-go/eip"
	"k8s.io/autoscaler/cluster-autoscaler/cloudprovider/baiducloud/baiducloud-sdk-go/util"
)

const (
	// InstanceStatusRunning status
	InstanceStatusRunning string = "Running"
	// InstanceStatusStarting status
	InstanceStatusStarting string = "Starting"
	// InstanceStatusStopping status
	InstanceStatusStopping string = "Stopping"
	// InstanceStatusStopped status
	InstanceStatusStopped string = "Stopped"
	// InstanceStatusDeleted status
	InstanceStatusDeleted string = "Deleted"
	// InstanceStatusScaling status
	InstanceStatusScaling string = "Scaling"
	// InstanceStatusExpired status
	InstanceStatusExpired string = "Expired"
	// InstanceStatusError status
	InstanceStatusError string = "Error"
	// InstanceStatusSnapshotProcessing status
	InstanceStatusSnapshotProcessing string = "SnapshotProcessing"
	// InstanceStatusImageProcessing statu
	InstanceStatusImageProcessing string = "ImageProcessing"
)

// Instance define instance model
type Instance struct {
	InstanceID            string `json:"id"`
	InstanceName          string `json:"name"`
	Description           string `json:"desc"`
	Status                string `json:"status"`
	PaymentTiming         string `json:"paymentTiming"`
	CreationTime          string `json:"createTime"`
	ExpireTime            string `json:"expireTime"`
	PublicIP              string `json:"publicIp"`
	InternalIP            string `json:"internalIp"`
	CPUCount              int    `json:"cpuCount"`
	GPUCount              int    `json:"gpuCount"`
	MemoryCapacityInGB    int    `json:"memoryCapacityInGB"`
	LocalDiskSizeInGB     int    `json:"localDiskSizeInGB"`
	ImageID               string `json:"imageId"`
	NetworkCapacityInMbps int    `json:"networkCapacityInMbps"`
	PlacementPolicy       string `json:"placementPolicy"`
	ZoneName              string `json:"zoneName"`
	SubnetID              string `json:"subnetId"`
	VpcID                 string `json:"vpcId"`
}

// StorageType type
type StorageType string

// EphemeralDisk json
type EphemeralDisk struct {
	StorageType  StorageType `json:"storageType,storageType"`
	SizeInGB     int         `json:"sizeInGB,omitempty"`
	FreeSizeInGB int         `json:"freeSizeInGB,omitempty"`
}

// CreateCdsModel json
type CreateCdsModel struct {
	StorageType StorageType `json:"storageType,storageType"`
	SnapshotID  string      `json:"snapshotId,omitempty"`
	CdsSizeInGB int         `json:"cdsSizeInGB,omitempty"`
}

// ListInstancesResponse json
type ListInstancesResponse struct {
	Marker      string     `json:"marker"`
	IsTruncated bool       `json:"isTruncated"`
	NextMarker  string     `json:"nextMarker"`
	MaxKeys     int        `json:"maxKeys"`
	Instances   []Instance `json:"instances"`
}

// CreateInstanceArgs is args to create instances
// refers to https://cloud.baidu.com/doc/BCC/API.html#.E5.88.9B.E5.BB.BA.E5.AE.9E.E4.BE.8B
type CreateInstanceArgs struct {
	ImageID               string           `json:"imageId"`
	Billing               billing.Billing  `json:"billing"`
	InstanceType          string           `json:"instanceType,omitempty"`
	CPUCount              int              `json:"cpuCount"`
	MemoryCapacityInGB    int              `json:"memoryCapacityInGB"`
	RootDiskSizeInGB      int              `json:"rootDiskSizeInGb,omitempty"`
	RootDiskStorageType   int              `json:"rootDiskStorageType,omitempty"`
	LocalDiskSizeInGB     int              `json:"localDiskSizeInGB,omitempty"` // deprecated now
	EphemeralDisks        []EphemeralDisk  `json:"ephemeralDisks,omitempty"`
	CreateCdsList         []CreateCdsModel `json:"createCdsList,omitempty"`
	NetworkCapacityInMbps int              `json:"networkCapacityInMbps,omitempty"`
	DedicatedHostID       int              `json:"dedicatedHostId,omitempty"`
	PurchaseCount         int              `json:"purchaseCount,omitempty"`
	Name                  string           `json:"name,omitempty"`
	AdminPass             string           `json:"adminPass,omitempty"`
	ZoneName              string           `json:"zoneName,omitempty"`
	SubnetID              string           `json:"subnetId,omitempty"`
	SecurityGroupID       string           `json:"securityGroupId,omitempty"`
	GPUCard               string           `json:"gpuCard,omitempty"`
	FPGACard              string           `json:"fpgaCard,omitempty"`
	CardCount             string           `json:"cardCount,omitempty"`
}

// CreateInstanceResponse is response of create instances
type CreateInstanceResponse struct {
	InstanceIDs []string `json:"instanceIds"`
}

// GetInstanceResponse json
type GetInstanceResponse struct {
	Ins Instance `json:"instance"`
}

func (args *CreateInstanceArgs) validate() error {
	if args == nil {
		return fmt.Errorf("CreateInstanceArgs cannot be nil")
	}
	if args.ImageID == "" {
		return fmt.Errorf("imageId cannot be empty")
	}
	if args.CPUCount <= 0 {
		return fmt.Errorf("cpuCount must be positive integer")
	}
	if args.MemoryCapacityInGB <= 0 {
		return fmt.Errorf("memoryCapacityInGB must be positive integer")
	}
	return nil
}

// CreateInstances create instances according to args
func (c *Client) CreateInstances(args *CreateInstanceArgs, option *bce.SignOption) ([]string, error) {
	var instanceIDs []string
	if err := args.validate(); err != nil {
		return instanceIDs, err
	}
	params := map[string]string{
		"clientToken": c.GenerateClientToken(),
	}
	// ref: https://cloud.baidu.com/doc/BCC/API.html#.7A.E6.31.D8.94.C1.A1.C2.1A.8D.92.ED.7F.60.7D.AF
	if len(args.AdminPass) != 0 {
		encrypted, err := util.AesECBEncryptHex(c.SecretAccessKey, args.AdminPass)
		if err != nil {
			return instanceIDs, err
		}
		args.AdminPass = encrypted
	}
	postContent, err := json.Marshal(args)
	if err != nil {
		return instanceIDs, err
	}
	req, err := bce.NewRequest("POST", c.GetURL("v2/instance", params), bytes.NewBuffer(postContent))
	if err != nil {
		return instanceIDs, err
	}
	resp, err := c.SendRequest(req, option)
	if err != nil {
		return instanceIDs, err
	}
	bodyContent, err := resp.GetBodyContent()
	if err != nil {
		return instanceIDs, err
	}
	var ciResp *CreateInstanceResponse
	if err := json.Unmarshal(bodyContent, &ciResp); err != nil {
		return instanceIDs, err
	}
	return ciResp.InstanceIDs, nil
}

// ListInstances gets all Instances.
func (c *Client) ListInstances(option *bce.SignOption) ([]Instance, error) {
	req, err := bce.NewRequest("GET", c.GetURL("v2/instance", nil), nil)
	if err != nil {
		return nil, err
	}
	resp, err := c.SendRequest(req, option)
	if err != nil {
		return nil, err
	}
	bodyContent, err := resp.GetBodyContent()
	if err != nil {
		return nil, err
	}
	var insList *ListInstancesResponse
	err = json.Unmarshal(bodyContent, &insList)
	if err != nil {
		return nil, err
	}
	return insList.Instances, nil
}

// DescribeInstance describe a instance
func (c *Client) DescribeInstance(instanceID string, option *bce.SignOption) (*Instance, error) {
	req, err := bce.NewRequest("GET", c.GetURL("v2/instance"+"/"+instanceID, nil), nil)
	if err != nil {
		return nil, err
	}
	resp, err := c.SendRequest(req, option)
	if err != nil {
		return nil, err
	}
	bodyContent, err := resp.GetBodyContent()
	if err != nil {
		return nil, err
	}
	var ins GetInstanceResponse
	err = json.Unmarshal(bodyContent, &ins)
	if err != nil {
		return nil, err
	}
	return &ins.Ins, nil
}

// DeleteInstance delete a instance
func (c *Client) DeleteInstance(instanceID string, option *bce.SignOption) error {
	instance, err := c.DescribeInstance(instanceID, nil)
	if err != nil {
		return err
	}
	// release eip if necessary
	if len(instance.PublicIP) != 0 {
		eipClient := eip.NewEIPClient(c.Config)
		eipArg := &eip.EipArgs{
			Ip: instance.PublicIP,
		}
		// not return err even if failed
		eipClient.UnbindEip(eipArg)
		eipClient.DeleteEip(eipArg)
	}
	req, err := bce.NewRequest("DELETE", c.GetURL("v2/instance"+"/"+instanceID, nil), nil)
	if err != nil {
		return err
	}
	_, err = c.SendRequest(req, option)
	if err != nil {
		return err
	}
	return nil
}