/*
Copyright 2017 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 fake

import (
	"context"
	"errors"
	"fmt"
	"io/ioutil"
	"os"
	"strings"

	csipb "github.com/container-storage-interface/spec/lib/go/csi"
	"google.golang.org/grpc"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/status"
)

const (
	// NodePublishTimeOut_VolumeID is volume id that will result in NodePublish operation to timeout
	NodePublishTimeOut_VolumeID = "node-publish-timeout"

	// NodeStageTimeOut_VolumeID is a volume id that will result in NodeStage operation to timeout
	NodeStageTimeOut_VolumeID = "node-stage-timeout"
)

// IdentityClient is a CSI identity client used for testing
type IdentityClient struct {
	nextErr error
}

// NewIdentityClient returns a new IdentityClient
func NewIdentityClient() *IdentityClient {
	return &IdentityClient{}
}

// SetNextError injects expected error
func (f *IdentityClient) SetNextError(err error) {
	f.nextErr = err
}

// GetPluginInfo returns plugin info
func (f *IdentityClient) GetPluginInfo(ctx context.Context, in *csipb.GetPluginInfoRequest, opts ...grpc.CallOption) (*csipb.GetPluginInfoResponse, error) {
	return nil, nil
}

// GetPluginCapabilities implements csi method
func (f *IdentityClient) GetPluginCapabilities(ctx context.Context, in *csipb.GetPluginCapabilitiesRequest, opts ...grpc.CallOption) (*csipb.GetPluginCapabilitiesResponse, error) {
	return nil, nil
}

// Probe implements csi method
func (f *IdentityClient) Probe(ctx context.Context, in *csipb.ProbeRequest, opts ...grpc.CallOption) (*csipb.ProbeResponse, error) {
	return nil, nil
}

type CSIVolume struct {
	VolumeHandle     string
	VolumeContext    map[string]string
	Path             string
	DeviceMountPath  string
	FSType           string
	MountFlags       []string
	VolumeMountGroup string
}

// NodeClient returns CSI node client
type NodeClient struct {
	nodePublishedVolumes     map[string]CSIVolume
	nodeStagedVolumes        map[string]CSIVolume
	stageUnstageSet          bool
	expansionSet             bool
	volumeStatsSet           bool
	volumeConditionSet       bool
	singleNodeMultiWriterSet bool
	volumeMountGroupSet      bool
	nodeGetInfoResp          *csipb.NodeGetInfoResponse
	nodeVolumeStatsResp      *csipb.NodeGetVolumeStatsResponse
	FakeNodeExpansionRequest *csipb.NodeExpandVolumeRequest
	nextErr                  error
}

// NewNodeClient returns fake node client
func NewNodeClient(stageUnstageSet bool) *NodeClient {
	return &NodeClient{
		nodePublishedVolumes: make(map[string]CSIVolume),
		nodeStagedVolumes:    make(map[string]CSIVolume),
		stageUnstageSet:      stageUnstageSet,
		volumeStatsSet:       true,
	}
}

func NewNodeClientWithExpansion(stageUnstageSet bool, expansionSet bool) *NodeClient {
	return &NodeClient{
		nodePublishedVolumes: make(map[string]CSIVolume),
		nodeStagedVolumes:    make(map[string]CSIVolume),
		stageUnstageSet:      stageUnstageSet,
		expansionSet:         expansionSet,
	}
}

func NewNodeClientWithVolumeStats(volumeStatsSet bool) *NodeClient {
	return &NodeClient{
		volumeStatsSet: volumeStatsSet,
	}
}

func NewNodeClientWithVolumeStatsAndCondition(volumeStatsSet, volumeConditionSet bool) *NodeClient {
	return &NodeClient{
		volumeStatsSet:     volumeStatsSet,
		volumeConditionSet: volumeConditionSet,
	}
}

func NewNodeClientWithSingleNodeMultiWriter(singleNodeMultiWriterSet bool) *NodeClient {
	return &NodeClient{
		nodePublishedVolumes:     make(map[string]CSIVolume),
		nodeStagedVolumes:        make(map[string]CSIVolume),
		stageUnstageSet:          true,
		volumeStatsSet:           true,
		singleNodeMultiWriterSet: singleNodeMultiWriterSet,
	}
}

func NewNodeClientWithVolumeMountGroup(stageUnstageSet, volumeMountGroupSet bool) *NodeClient {
	return &NodeClient{
		nodePublishedVolumes: make(map[string]CSIVolume),
		nodeStagedVolumes:    make(map[string]CSIVolume),
		stageUnstageSet:      stageUnstageSet,
		volumeMountGroupSet:  volumeMountGroupSet,
	}
}

// SetNextError injects next expected error
func (f *NodeClient) SetNextError(err error) {
	f.nextErr = err
}

func (f *NodeClient) SetNodeGetInfoResp(resp *csipb.NodeGetInfoResponse) {
	f.nodeGetInfoResp = resp
}

func (f *NodeClient) SetNodeVolumeStatsResp(resp *csipb.NodeGetVolumeStatsResponse) {
	f.nodeVolumeStatsResp = resp
}

// GetNodePublishedVolumes returns node published volumes
func (f *NodeClient) GetNodePublishedVolumes() map[string]CSIVolume {
	return f.nodePublishedVolumes
}

// AddNodePublishedVolume adds specified volume to nodePublishedVolumes
func (f *NodeClient) AddNodePublishedVolume(volID, deviceMountPath string, volumeContext map[string]string) {
	f.nodePublishedVolumes[volID] = CSIVolume{
		Path:          deviceMountPath,
		VolumeContext: volumeContext,
	}
}

// GetNodeStagedVolumes returns node staged volumes
func (f *NodeClient) GetNodeStagedVolumes() map[string]CSIVolume {
	return f.nodeStagedVolumes
}

// AddNodeStagedVolume adds specified volume to nodeStagedVolumes
func (f *NodeClient) AddNodeStagedVolume(volID, deviceMountPath string, volumeContext map[string]string) {
	f.nodeStagedVolumes[volID] = CSIVolume{
		Path:          deviceMountPath,
		VolumeContext: volumeContext,
	}
}

// NodePublishVolume implements CSI NodePublishVolume
func (f *NodeClient) NodePublishVolume(ctx context.Context, req *csipb.NodePublishVolumeRequest, opts ...grpc.CallOption) (*csipb.NodePublishVolumeResponse, error) {
	if f.nextErr != nil {
		return nil, f.nextErr
	}

	if req.GetVolumeId() == "" {
		return nil, errors.New("missing volume id")
	}
	if req.GetTargetPath() == "" {
		return nil, errors.New("missing target path")
	}
	fsTypes := "block|ext4|xfs|zfs"
	fsType := req.GetVolumeCapability().GetMount().GetFsType()
	if !strings.Contains(fsTypes, fsType) {
		return nil, errors.New("invalid fstype")
	}

	if req.GetVolumeId() == NodePublishTimeOut_VolumeID {
		timeoutErr := status.Errorf(codes.DeadlineExceeded, "timeout exceeded")
		return nil, timeoutErr
	}

	// "Creation of target_path is the responsibility of the SP."
	// Our plugin depends on it.
	if req.VolumeCapability.GetBlock() != nil {
		if err := ioutil.WriteFile(req.TargetPath, []byte{}, 0644); err != nil {
			return nil, fmt.Errorf("cannot create target path %s for block file: %s", req.TargetPath, err)
		}
	} else {
		if err := os.MkdirAll(req.TargetPath, 0755); err != nil {
			return nil, fmt.Errorf("cannot create target directory %s for mount: %s", req.TargetPath, err)
		}
	}

	publishedVolume := CSIVolume{
		VolumeHandle:    req.GetVolumeId(),
		Path:            req.GetTargetPath(),
		DeviceMountPath: req.GetStagingTargetPath(),
		VolumeContext:   req.GetVolumeContext(),
	}
	if req.GetVolumeCapability().GetMount() != nil {
		publishedVolume.FSType = req.GetVolumeCapability().GetMount().FsType
		publishedVolume.MountFlags = req.GetVolumeCapability().GetMount().MountFlags
		publishedVolume.VolumeMountGroup = req.GetVolumeCapability().GetMount().VolumeMountGroup
	}
	f.nodePublishedVolumes[req.GetVolumeId()] = publishedVolume
	return &csipb.NodePublishVolumeResponse{}, nil
}

// NodeUnpublishVolume implements csi method
func (f *NodeClient) NodeUnpublishVolume(ctx context.Context, req *csipb.NodeUnpublishVolumeRequest, opts ...grpc.CallOption) (*csipb.NodeUnpublishVolumeResponse, error) {
	if f.nextErr != nil {
		return nil, f.nextErr
	}

	if req.GetVolumeId() == "" {
		return nil, errors.New("missing volume id")
	}
	if req.GetTargetPath() == "" {
		return nil, errors.New("missing target path")
	}
	delete(f.nodePublishedVolumes, req.GetVolumeId())

	// "The SP MUST delete the file or directory it created at this path."
	if err := os.Remove(req.TargetPath); err != nil && !os.IsNotExist(err) {
		return nil, fmt.Errorf("failed to remove publish path %s: %s", req.TargetPath, err)
	}

	return &csipb.NodeUnpublishVolumeResponse{}, nil
}

// NodeStagevolume implements csi method
func (f *NodeClient) NodeStageVolume(ctx context.Context, req *csipb.NodeStageVolumeRequest, opts ...grpc.CallOption) (*csipb.NodeStageVolumeResponse, error) {
	if f.nextErr != nil {
		return nil, f.nextErr
	}

	if req.GetVolumeId() == "" {
		return nil, errors.New("missing volume id")
	}
	if req.GetStagingTargetPath() == "" {
		return nil, errors.New("missing staging target path")
	}

	csiVol := CSIVolume{
		Path:          req.GetStagingTargetPath(),
		VolumeContext: req.GetVolumeContext(),
	}

	fsType := ""
	fsTypes := "block|ext4|xfs|zfs"
	mounted := req.GetVolumeCapability().GetMount()
	if mounted != nil {
		fsType = mounted.GetFsType()
		csiVol.MountFlags = mounted.GetMountFlags()
		csiVol.VolumeMountGroup = mounted.VolumeMountGroup
	}
	if !strings.Contains(fsTypes, fsType) {
		return nil, errors.New("invalid fstype")
	}

	if req.GetVolumeId() == NodeStageTimeOut_VolumeID {
		timeoutErr := status.Errorf(codes.DeadlineExceeded, "timeout exceeded")
		return nil, timeoutErr
	}

	f.nodeStagedVolumes[req.GetVolumeId()] = csiVol
	return &csipb.NodeStageVolumeResponse{}, nil
}

// NodeUnstageVolume implements csi method
func (f *NodeClient) NodeUnstageVolume(ctx context.Context, req *csipb.NodeUnstageVolumeRequest, opts ...grpc.CallOption) (*csipb.NodeUnstageVolumeResponse, error) {
	if f.nextErr != nil {
		return nil, f.nextErr
	}

	if req.GetVolumeId() == "" {
		return nil, errors.New("missing volume id")
	}
	if req.GetStagingTargetPath() == "" {
		return nil, errors.New("missing staging target path")
	}

	delete(f.nodeStagedVolumes, req.GetVolumeId())
	return &csipb.NodeUnstageVolumeResponse{}, nil
}

// NodeExpandVolume implements csi method
func (f *NodeClient) NodeExpandVolume(ctx context.Context, req *csipb.NodeExpandVolumeRequest, opts ...grpc.CallOption) (*csipb.NodeExpandVolumeResponse, error) {
	if f.nextErr != nil {
		return nil, f.nextErr
	}

	if req.GetVolumeId() == "" {
		return nil, errors.New("missing volume id")
	}
	if req.GetVolumePath() == "" {
		return nil, errors.New("missing volume path")
	}

	if req.GetCapacityRange().RequiredBytes <= 0 {
		return nil, errors.New("required bytes should be greater than 0")
	}

	f.FakeNodeExpansionRequest = req

	resp := &csipb.NodeExpandVolumeResponse{
		CapacityBytes: req.GetCapacityRange().RequiredBytes,
	}
	return resp, nil
}

// NodeGetId implements csi method
func (f *NodeClient) NodeGetInfo(ctx context.Context, in *csipb.NodeGetInfoRequest, opts ...grpc.CallOption) (*csipb.NodeGetInfoResponse, error) {
	if f.nextErr != nil {
		return nil, f.nextErr
	}
	return f.nodeGetInfoResp, nil
}

// NodeGetCapabilities implements csi method
func (f *NodeClient) NodeGetCapabilities(ctx context.Context, in *csipb.NodeGetCapabilitiesRequest, opts ...grpc.CallOption) (*csipb.NodeGetCapabilitiesResponse, error) {
	resp := &csipb.NodeGetCapabilitiesResponse{
		Capabilities: []*csipb.NodeServiceCapability{},
	}
	if f.stageUnstageSet {
		resp.Capabilities = append(resp.Capabilities, &csipb.NodeServiceCapability{
			Type: &csipb.NodeServiceCapability_Rpc{
				Rpc: &csipb.NodeServiceCapability_RPC{
					Type: csipb.NodeServiceCapability_RPC_STAGE_UNSTAGE_VOLUME,
				},
			},
		})
	}
	if f.expansionSet {
		resp.Capabilities = append(resp.Capabilities, &csipb.NodeServiceCapability{
			Type: &csipb.NodeServiceCapability_Rpc{
				Rpc: &csipb.NodeServiceCapability_RPC{
					Type: csipb.NodeServiceCapability_RPC_EXPAND_VOLUME,
				},
			},
		})
	}

	if f.volumeStatsSet {
		resp.Capabilities = append(resp.Capabilities, &csipb.NodeServiceCapability{
			Type: &csipb.NodeServiceCapability_Rpc{
				Rpc: &csipb.NodeServiceCapability_RPC{
					Type: csipb.NodeServiceCapability_RPC_GET_VOLUME_STATS,
				},
			},
		})
	}

	if f.volumeConditionSet {
		resp.Capabilities = append(resp.Capabilities, &csipb.NodeServiceCapability{
			Type: &csipb.NodeServiceCapability_Rpc{
				Rpc: &csipb.NodeServiceCapability_RPC{
					Type: csipb.NodeServiceCapability_RPC_VOLUME_CONDITION,
				},
			},
		})
	}

	if f.singleNodeMultiWriterSet {
		resp.Capabilities = append(resp.Capabilities, &csipb.NodeServiceCapability{
			Type: &csipb.NodeServiceCapability_Rpc{
				Rpc: &csipb.NodeServiceCapability_RPC{
					Type: csipb.NodeServiceCapability_RPC_SINGLE_NODE_MULTI_WRITER,
				},
			},
		})
	}

	if f.volumeMountGroupSet {
		resp.Capabilities = append(resp.Capabilities, &csipb.NodeServiceCapability{
			Type: &csipb.NodeServiceCapability_Rpc{
				Rpc: &csipb.NodeServiceCapability_RPC{
					Type: csipb.NodeServiceCapability_RPC_VOLUME_MOUNT_GROUP,
				},
			},
		})
	}
	return resp, nil
}

/*
// NodeGetVolumeStats implements csi method
func (f *NodeClient) NodeGetVolumeStats(ctx context.Context, in *csipb.NodeGetVolumeStatsRequest, opts ...grpc.CallOption) (*csipb.NodeGetVolumeStatsResponse, error) {
	return nil, nil
}
*/

// NodeGetVolumeStats implements csi method
func (f *NodeClient) NodeGetVolumeStats(ctx context.Context, req *csipb.NodeGetVolumeStatsRequest, opts ...grpc.CallOption) (*csipb.NodeGetVolumeStatsResponse, error) {
	if f.nextErr != nil {
		return nil, f.nextErr
	}
	if req.GetVolumeId() == "" {
		return nil, errors.New("missing volume id")
	}
	if req.GetVolumePath() == "" {
		return nil, errors.New("missing Volume path")
	}
	if f.nodeVolumeStatsResp != nil {
		return f.nodeVolumeStatsResp, nil
	}
	return &csipb.NodeGetVolumeStatsResponse{}, nil
}

// ControllerClient represents a CSI Controller client
type ControllerClient struct {
	nextCapabilities []*csipb.ControllerServiceCapability
	nextErr          error
}

// NewControllerClient returns a ControllerClient
func NewControllerClient() *ControllerClient {
	return &ControllerClient{}
}

// SetNextError injects next expected error
func (f *ControllerClient) SetNextError(err error) {
	f.nextErr = err
}

// SetNextCapabilities injects next expected capabilities
func (f *ControllerClient) SetNextCapabilities(caps []*csipb.ControllerServiceCapability) {
	f.nextCapabilities = caps
}

// ControllerGetCapabilities implements csi method
func (f *ControllerClient) ControllerGetCapabilities(ctx context.Context, in *csipb.ControllerGetCapabilitiesRequest, opts ...grpc.CallOption) (*csipb.ControllerGetCapabilitiesResponse, error) {
	if f.nextErr != nil {
		return nil, f.nextErr
	}

	if f.nextCapabilities == nil {
		f.nextCapabilities = []*csipb.ControllerServiceCapability{
			{
				Type: &csipb.ControllerServiceCapability_Rpc{
					Rpc: &csipb.ControllerServiceCapability_RPC{
						Type: csipb.ControllerServiceCapability_RPC_PUBLISH_UNPUBLISH_VOLUME,
					},
				},
			},
		}
	}
	return &csipb.ControllerGetCapabilitiesResponse{
		Capabilities: f.nextCapabilities,
	}, nil
}

// CreateVolume implements csi method
func (f *ControllerClient) CreateVolume(ctx context.Context, in *csipb.CreateVolumeRequest, opts ...grpc.CallOption) (*csipb.CreateVolumeResponse, error) {
	return nil, nil
}

// DeleteVolume implements csi method
func (f *ControllerClient) DeleteVolume(ctx context.Context, in *csipb.DeleteVolumeRequest, opts ...grpc.CallOption) (*csipb.DeleteVolumeResponse, error) {
	return nil, nil
}

// ControllerPublishVolume implements csi method
func (f *ControllerClient) ControllerPublishVolume(ctx context.Context, in *csipb.ControllerPublishVolumeRequest, opts ...grpc.CallOption) (*csipb.ControllerPublishVolumeResponse, error) {
	return nil, nil
}

// ControllerUnpublishVolume implements csi method
func (f *ControllerClient) ControllerUnpublishVolume(ctx context.Context, in *csipb.ControllerUnpublishVolumeRequest, opts ...grpc.CallOption) (*csipb.ControllerUnpublishVolumeResponse, error) {
	return nil, nil
}

// ValidateVolumeCapabilities implements csi method
func (f *ControllerClient) ValidateVolumeCapabilities(ctx context.Context, in *csipb.ValidateVolumeCapabilitiesRequest, opts ...grpc.CallOption) (*csipb.ValidateVolumeCapabilitiesResponse, error) {
	return nil, nil
}

// ListVolumes implements csi method
func (f *ControllerClient) ListVolumes(ctx context.Context, in *csipb.ListVolumesRequest, opts ...grpc.CallOption) (*csipb.ListVolumesResponse, error) {
	return nil, nil
}

// GetCapacity implements csi method
func (f *ControllerClient) GetCapacity(ctx context.Context, in *csipb.GetCapacityRequest, opts ...grpc.CallOption) (*csipb.GetCapacityResponse, error) {
	return nil, nil
}
