module Hem
  module Lib
    module Vm
      class Command
        class << self
          attr_accessor :vm_inspector
          @@vm_inspector = Inspector.new
        end

        attr_accessor :opts, :command

        def initialize command, opts = {}
          @command = command
          @opts = {
              :auto_echo => false,
              :psuedo_tty => false,
              :pwd => opts[:pwd] || @@vm_inspector.project_mount_path,
              :append => ''
          }.merge(opts)
        end

        def pipe cmd, pipe_opts = {}
          pipe_opts = pipe_opts.merge({ :on => :vm })
          cmd = "echo #{cmd.shellescape}" if @opts[:auto_echo]

          case pipe_opts[:on]
            when :vm
              @pipe_in_vm = cmd
            when :host
              @pipe = cmd
            else
              raise "Unknown pipe source: #{pipe_opts[:on]}"
          end
          @opts[:psuedo_tty] = false
          return self
        end

        def << cmd
          pipe cmd, :on => :host
        end

        def < cmd
          pipe cmd, :on => :vm
        end

        def run
          return if @command.nil?
          Hem::Helper.shell to_s, @opts
        end

        # TODO Speed up Vagrant SSH connections
        # May need to be disabled for windows (mm_send_fd: UsePrivilegeSeparation=yes not supported)
        # https://gist.github.com/jedi4ever/5657094

        def to_s
          require 'tempfile'
          config = ::Tempfile.new 'hem_ssh_config'
          config.write @@vm_inspector.ssh_config
          config.close

          psuedo_tty = opts[:psuedo_tty] ? '-t' : ''

          ssh_command = [
              'ssh',
              "-F #{config.path.shellescape}",
              psuedo_tty,
              'default'
          ].join(' ')

          pwd_set_command = " -- \"cd #{@opts[:pwd].shellescape}; exec /bin/bash"

          vm_command = [
              @pipe_in_vm.nil? ? nil : @pipe_in_vm.gsub(/(\\+)/, '\\\\\1'),
              @command
          ].compact.join(' | ')

          command = [
              ssh_command + pwd_set_command,
              vm_command.empty? ? nil : vm_command.shellescape
          ].compact.join(' -c ') + "#{@opts[:append].shellescape}\""

          [
              @pipe,
              command
          ].compact.join(' | ')
        end

        def to_str
          to_s
        end
      end
    end
  end
end