package common

import (
	"context"
	"fmt"
	"log"
	"path/filepath"
	"strings"

	"github.com/hashicorp/packer/packer-plugin-sdk/multistep"
	packersdk "github.com/hashicorp/packer/packer-plugin-sdk/packer"
)

// This step creates the actual virtual machine.
//
// Produces:
//   VMName string - The name of the VM
type StepCreateVM struct {
	VMName                         string
	SwitchName                     string
	HarddrivePath                  string
	RamSize                        uint
	DiskSize                       uint
	DiskBlockSize                  uint
	UseLegacyNetworkAdapter        bool
	Generation                     uint
	Cpu                            uint
	EnableMacSpoofing              bool
	EnableDynamicMemory            bool
	EnableSecureBoot               bool
	SecureBootTemplate             string
	EnableVirtualizationExtensions bool
	AdditionalDiskSize             []uint
	DifferencingDisk               bool
	MacAddress                     string
	FixedVHD                       bool
	Version                        string
	KeepRegistered                 bool
}

func (s *StepCreateVM) Run(ctx context.Context, state multistep.StateBag) multistep.StepAction {
	driver := state.Get("driver").(Driver)
	ui := state.Get("ui").(packersdk.Ui)
	ui.Say("Creating virtual machine...")

	var path string
	if v, ok := state.GetOk("build_dir"); ok {
		path = v.(string)
	}

	err := driver.CheckVMName(s.VMName)
	if err != nil {
		s.KeepRegistered = true
		state.Put("error", err)
		ui.Error(err.Error())
		return multistep.ActionHalt
	}

	// Determine if we even have an existing virtual harddrive to attach
	harddrivePath := ""
	if harddrivePathRaw, ok := state.GetOk("iso_path"); ok {
		extension := strings.ToLower(filepath.Ext(harddrivePathRaw.(string)))
		if extension == ".vhd" || extension == ".vhdx" {
			harddrivePath = harddrivePathRaw.(string)
		} else {
			log.Println("No existing virtual harddrive, not attaching.")
		}
	} else {
		log.Println("No existing virtual harddrive, not attaching.")
	}

	// convert the MB to bytes
	ramSize := int64(s.RamSize) * 1024 * 1024
	diskSize := int64(s.DiskSize) * 1024 * 1024
	diskBlockSize := int64(s.DiskBlockSize) * 1024 * 1024

	err = driver.CreateVirtualMachine(s.VMName, path, harddrivePath, ramSize, diskSize, diskBlockSize,
		s.SwitchName, s.Generation, s.DifferencingDisk, s.FixedVHD, s.Version)
	if err != nil {
		err := fmt.Errorf("Error creating virtual machine: %s", err)
		state.Put("error", err)
		ui.Error(err.Error())
		return multistep.ActionHalt
	}

	if s.UseLegacyNetworkAdapter {
		err := driver.ReplaceVirtualMachineNetworkAdapter(s.VMName, true)
		if err != nil {
			err := fmt.Errorf("Error creating legacy network adapter: %s", err)
			state.Put("error", err)
			ui.Error(err.Error())
			return multistep.ActionHalt
		}
	}

	err = driver.SetVirtualMachineCpuCount(s.VMName, s.Cpu)
	if err != nil {
		err := fmt.Errorf("Error setting virtual machine cpu count: %s", err)
		state.Put("error", err)
		ui.Error(err.Error())
		return multistep.ActionHalt
	}

	err = driver.SetVirtualMachineDynamicMemory(s.VMName, s.EnableDynamicMemory)
	if err != nil {
		err := fmt.Errorf("Error setting virtual machine dynamic memory: %s", err)
		state.Put("error", err)
		ui.Error(err.Error())
		return multistep.ActionHalt
	}

	if s.EnableMacSpoofing {
		err = driver.SetVirtualMachineMacSpoofing(s.VMName, s.EnableMacSpoofing)
		if err != nil {
			err := fmt.Errorf("Error setting virtual machine mac spoofing: %s", err)
			state.Put("error", err)
			ui.Error(err.Error())
			return multistep.ActionHalt
		}
	}

	if s.Generation == 2 {
		err = driver.SetVirtualMachineSecureBoot(s.VMName, s.EnableSecureBoot, s.SecureBootTemplate)
		if err != nil {
			err := fmt.Errorf("Error setting secure boot: %s", err)
			state.Put("error", err)
			ui.Error(err.Error())
			return multistep.ActionHalt
		}
	}

	if s.EnableVirtualizationExtensions {
		//This is only supported on Windows 10 and Windows Server 2016 onwards
		err = driver.SetVirtualMachineVirtualizationExtensions(s.VMName, s.EnableVirtualizationExtensions)
		if err != nil {
			err := fmt.Errorf("Error setting virtual machine virtualization extensions: %s", err)
			state.Put("error", err)
			ui.Error(err.Error())
			return multistep.ActionHalt
		}
	}

	if len(s.AdditionalDiskSize) > 0 {
		for index, size := range s.AdditionalDiskSize {
			diskSize := int64(size * 1024 * 1024)
			diskFile := fmt.Sprintf("%s-%d.vhdx", s.VMName, index)
			err = driver.AddVirtualMachineHardDrive(s.VMName, path, diskFile, diskSize, diskBlockSize, "SCSI")
			if err != nil {
				err := fmt.Errorf("Error creating and attaching additional disk drive: %s", err)
				state.Put("error", err)
				ui.Error(err.Error())
				return multistep.ActionHalt
			}
		}
	}

	if s.MacAddress != "" {
		err = driver.SetVmNetworkAdapterMacAddress(s.VMName, s.MacAddress)
		if err != nil {
			err := fmt.Errorf("Error setting MAC address: %s", err)
			state.Put("error", err)
			ui.Error(err.Error())
			return multistep.ActionHalt
		}
	}

	// Set the final name in the state bag so others can use it
	state.Put("vmName", s.VMName)
	// instance_id is the generic term used so that users can have access to the
	// instance id inside of the provisioners, used in step_provision.
	state.Put("instance_id", s.VMName)

	return multistep.ActionContinue
}

func (s *StepCreateVM) Cleanup(state multistep.StateBag) {
	if s.VMName == "" {
		return
	}

	driver := state.Get("driver").(Driver)
	ui := state.Get("ui").(packersdk.Ui)

	if s.KeepRegistered {
		ui.Say("keep_registered set. Skipping unregister/deletion of VM.")
		return
	}

	ui.Say("Unregistering and deleting virtual machine...")

	err := driver.DeleteVirtualMachine(s.VMName)
	if err != nil {
		ui.Error(fmt.Sprintf("Error deleting virtual machine: %s", err))
	}

	// TODO: Clean up created VHDX
}