/*
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 cephfs

import (
	"fmt"

	"github.com/golang/glog"
	"golang.org/x/net/context"
	"google.golang.org/grpc/codes"
	"google.golang.org/grpc/status"

	"github.com/container-storage-interface/spec/lib/go/csi/v0"
	"github.com/kubernetes-csi/drivers/pkg/csi-common"
)

type controllerServer struct {
	*csicommon.DefaultControllerServer
}

const (
	oneGB = 1073741824
)

func (cs *controllerServer) validateCreateVolumeRequest(req *csi.CreateVolumeRequest) error {
	if err := cs.Driver.ValidateControllerServiceRequest(csi.ControllerServiceCapability_RPC_CREATE_DELETE_VOLUME); err != nil {
		return fmt.Errorf("Invalid CreateVolumeRequest: %v", err)
	}

	if req.GetName() == "" {
		return status.Error(codes.InvalidArgument, "Volume Name cannot be empty")
	}

	if req.GetVolumeCapabilities() == nil {
		return status.Error(codes.InvalidArgument, "Volume Capabilities cannot be empty")
	}

	return nil
}

func (cs *controllerServer) validateDeleteVolumeRequest(req *csi.DeleteVolumeRequest) error {
	if err := cs.Driver.ValidateControllerServiceRequest(csi.ControllerServiceCapability_RPC_CREATE_DELETE_VOLUME); err != nil {
		return fmt.Errorf("Invalid DeleteVolumeRequest: %v", err)
	}

	return nil
}

func (cs *controllerServer) CreateVolume(ctx context.Context, req *csi.CreateVolumeRequest) (*csi.CreateVolumeResponse, error) {
	if err := cs.validateCreateVolumeRequest(req); err != nil {
		glog.Errorf("CreateVolumeRequest validation failed: %v", err)
		return nil, err
	}

	volOptions, err := newVolumeOptions(req.GetParameters())
	if err != nil {
		glog.Errorf("error reading volume options: %v", err)
		return nil, status.Error(codes.InvalidArgument, err.Error())
	}

	volId := newVolumeIdentifier(volOptions, req)

	conf := cephConfigData{Monitors: volOptions.Monitors}
	if err = conf.writeToFile(); err != nil {
		glog.Errorf("couldn't generate ceph.conf: %v", err)
		return nil, status.Error(codes.Internal, err.Error())
	}

	glog.V(4).Infof("cephfs: volume %s successfuly created", volId.id)

	return &csi.CreateVolumeResponse{
		Volume: &csi.Volume{
			Id:            volId.id,
			CapacityBytes: req.GetCapacityRange().GetRequiredBytes(),
			Attributes:    req.GetParameters(),
		},
	}, nil
}

func (cs *controllerServer) DeleteVolume(ctx context.Context, req *csi.DeleteVolumeRequest) (*csi.DeleteVolumeResponse, error) {
	if err := cs.validateDeleteVolumeRequest(req); err != nil {
		glog.Errorf("DeleteVolumeRequest validation failed: %v", err)
		return nil, err
	}

	// TODO

	return &csi.DeleteVolumeResponse{}, nil
}

func (cs *controllerServer) ValidateVolumeCapabilities(ctx context.Context, req *csi.ValidateVolumeCapabilitiesRequest) (*csi.ValidateVolumeCapabilitiesResponse, error) {
	return &csi.ValidateVolumeCapabilitiesResponse{Supported: true}, nil
}