require 'log4r'

require 'vagrant/util/busy'
require 'vagrant/util/platform'
require 'vagrant/util/retryable'
require 'vagrant/util/subprocess'

module Vagrant
  module Driver
    # Base class for all VirtualBox drivers.
    #
    # This class provides useful tools for things such as executing
    # VBoxManage and handling SIGINTs and so on.
    class VirtualBoxBase
      # Include this so we can use `Subprocess` more easily.
      include Vagrant::Util
      include Vagrant::Util::Retryable

      def initialize
        @logger = Log4r::Logger.new("vagrant::driver::virtualbox_base")

        # This flag is used to keep track of interrupted state (SIGINT)
        @interrupted = false

        # Set the path to VBoxManage
        @vboxmanage_path = "VBoxManage"

        if Util::Platform.windows?
          @logger.debug("Windows. Trying VBOX_INSTALL_PATH for VBoxManage")

          # On Windows, we use the VBOX_INSTALL_PATH environmental
          # variable to find VBoxManage.
          if ENV.has_key?("VBOX_INSTALL_PATH")
            # The path usually ends with a \ but we make sure here
            path = ENV["VBOX_INSTALL_PATH"]
            path += "\\" if !path.end_with?("\\")
            @vboxmanage_path = "#{path}VBoxManage.exe"
          end
        end

        @logger.info("VBoxManage path: #{@vboxmanage_path}")
      end

      # Clears the forwarded ports that have been set on the virtual machine.
      def clear_forwarded_ports
      end

      # Clears the shared folders that have been set on the virtual machine.
      def clear_shared_folders
      end

      # Creates a DHCP server for a host only network.
      #
      # @param [String] network Name of the host-only network.
      # @param [Hash] options Options for the DHCP server.
      def create_dhcp_server(network, options)
      end

      # Creates a host only network with the given options.
      #
      # @param [Hash] options Options to create the host only network.
      # @return [Hash] The details of the host only network, including
      #   keys `:name`, `:ip`, and `:netmask`
      def create_host_only_network(options)
      end

      # Deletes the virtual machine references by this driver.
      def delete
      end

      # Deletes any host only networks that aren't being used for anything.
      def delete_unused_host_only_networks
      end

      # Discards any saved state associated with this VM.
      def discard_saved_state
      end

      # Enables network adapters on the VM.
      #
      # The format of each adapter specification should be like so:
      #
      # {
      #   :type     => :hostonly,
      #   :hostonly => "vboxnet0",
      #   :mac_address => "tubes"
      # }
      #
      # This must support setting up both host only and bridged networks.
      #
      # @param [Array<Hash>] adapters Array of adapters to enable.
      def enable_adapters(adapters)
      end

      # Execute a raw command straight through to VBoxManage.
      #
      # @param [Array] command Command to execute.
      def execute_command(command)
      end

      # Exports the virtual machine to the given path.
      #
      # @param [String] path Path to the OVF file.
      # @yield [progress] Yields the block with the progress of the export.
      def export(path)
      end

      # Forwards a set of ports for a VM.
      #
      # This will not affect any previously set forwarded ports,
      # so be sure to delete those if you need to.
      #
      # The format of each port hash should be the following:
      #
      #     {
      #       :name => "foo",
      #       :hostport => 8500,
      #       :guestport => 80,
      #       :adapter => 1,
      #       :protocol => "tcp"
      #     }
      #
      # Note that "adapter" and "protocol" are optional and will default
      # to 1 and "tcp" respectively.
      #
      # @param [Array<Hash>] ports An array of ports to set. See documentation
      #   for more information on the format.
      def forward_ports(ports)
      end

      # Halts the virtual machine (pulls the plug).
      def halt
      end

      # Imports the VM from an OVF file.
      #
      # @param [String] ovf Path to the OVF file.
      # @return [String] UUID of the imported VM.
      def import(ovf)
      end

      # Returns a list of forwarded ports for a VM.
      #
      # @param [String] uuid UUID of the VM to read from, or `nil` if this
      #   VM.
      # @param [Boolean] active_only If true, only VMs that are running will
      #   be checked.
      # @return [Array<Array>]
      def read_forwarded_ports(uuid=nil, active_only=false)
      end

      # Returns a list of bridged interfaces.
      #
      # @return [Hash]
      def read_bridged_interfaces
      end

      # Returns the guest additions version that is installed on this VM.
      #
      # @return [String]
      def read_guest_additions_version
      end

      # Returns a list of available host only interfaces.
      #
      # @return [Hash]
      def read_host_only_interfaces
      end

      # Returns the MAC address of the first network interface.
      #
      # @return [String]
      def read_mac_address
      end

      # Returns the folder where VirtualBox places it's VMs.
      #
      # @return [String]
      def read_machine_folder
      end

      # Returns a list of network interfaces of the VM.
      #
      # @return [Hash]
      def read_network_interfaces
      end

      # Returns the current state of this VM.
      #
      # @return [Symbol]
      def read_state
      end

      # Returns a list of all forwarded ports in use by active
      # virtual machines.
      #
      # @return [Array]
      def read_used_ports
      end

      # Returns a list of all UUIDs of virtual machines currently
      # known by VirtualBox.
      #
      # @return [Array<String>]
      def read_vms
      end

      # Sets the MAC address of the first network adapter.
      #
      # @param [String] mac MAC address without any spaces/hyphens.
      def set_mac_address(mac)
      end

      # Share a set of folders on this VM.
      #
      # @param [Array<Hash>] folders
      def share_folders(folders)
      end

      # Reads the SSH port of this VM.
      #
      # @param [Integer] expected Expected guest port of SSH.
      def ssh_port(expected)
      end

      # Starts the virtual machine.
      #
      # @param [String] mode Mode to boot the VM. Either "headless"
      #   or "gui"
      def start(mode)
      end

      # Suspend the virtual machine.
      def suspend
      end

      # Verifies that the driver is ready to accept work.
      #
      # This should raise a VagrantError if things are not ready.
      def verify!
      end

      # Verifies that an image can be imported properly.
      #
      # @param [String] path Path to an OVF file.
      # @return [Boolean]
      def verify_image(path)
      end

      # Checks if a VM with the given UUID exists.
      #
      # @return [Boolean]
      def vm_exists?(uuid)
      end

      # Execute the given subcommand for VBoxManage and return the output.
      def execute(*command, &block)
        # Get the options hash if it exists
        opts = {}
        opts = command.pop if command.last.is_a?(Hash)

        tries = 0
        tries = 3 if opts[:retryable]

        # Variable to store our execution result
        r = nil

        retryable(:on => Errors::VBoxManageError, :tries => tries, :sleep => 1) do
          # Execute the command
          r = raw(*command, &block)

          # If the command was a failure, then raise an exception that is
          # nicely handled by Vagrant.
          if r.exit_code != 0
            if @interrupted
              @logger.info("Exit code != 0, but interrupted. Ignoring.")
            else
              raise Errors::VBoxManageError, :command => command.inspect
            end
          else
            # Sometimes, VBoxManage fails but doesn't actual return a non-zero
            # exit code. For this we inspect the output and determine if an error
            # occurred.
            if r.stderr =~ /VBoxManage: error:/
              @logger.info("VBoxManage error text found, assuming error.")
              raise Errors::VBoxManageError, :command => command.inspect
            end
          end
        end

        # Return the output, making sure to replace any Windows-style
        # newlines with Unix-style.
        r.stdout.gsub("\r\n", "\n")
      end

      # Executes a command and returns the raw result object.
      def raw(*command, &block)
        int_callback = lambda do
          @interrupted = true
          @logger.info("Interrupted.")
        end

        # The following is a workaround for a combined VirtualBox and
        # Mac OS X 10.8 bug:
        #
        # Remove the DYLD_LIBRARY_PATH environmental variable on Mac. This
        # is to fix a bug in Mac OS X 10.8 where a warning is printed to the
        # console if this is set when executing certain programs, which
        # can cause some VBoxManage commands to break because they work
        # by just reading stdout and don't expect the OS to just inject
        # garbage into it.
        old_dyld_lib_path = ENV.delete("DYLD_LIBRARY_PATH")
        old_ld_lib_path   = ENV.delete("LD_LIBRARY_PATH")

        Util::Busy.busy(int_callback) do
          Subprocess.execute(@vboxmanage_path, *command, &block)
        end
      ensure
        # Reset the library path if it was set before. See above comments
        # for more information on why this was unset in the first place.
        ENV["DYLD_LIBRARY_PATH"] = old_dyld_lib_path if old_dyld_lib_path
        ENV["LD_LIBRARY_PATH"]   = old_ld_lib_path if old_ld_lib_path
      end
    end
  end
end