# -*- encoding: utf-8 -*-
#
# Author:: Steven Murawski (<steven.murawski@gmail.com>)
#
# Copyright (C) 2015, Steven Murawski
#
# 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.

require "pathname"
require "kitchen/verifier/base"
require_relative "pester_version"

module Kitchen

  module Verifier

    class Pester < Kitchen::Verifier::Base

      kitchen_verifier_api_version 1

      plugin_version Kitchen::Verifier::PESTER_VERSION

      default_config :restart_winrm, false
      default_config :test_folder
      default_config :use_local_pester_module, false
      default_config :downloads, ["./PesterTestResults.xml"] => "./testresults"

      # Creates a new Verifier object using the provided configuration data
      # which will be merged with any default configuration.
      #
      # @param config [Hash] provided verifier configuration
      def initialize(config = {})
        init_config(config)
      end

      # Creates a temporary directory on the local workstation into which
      # verifier related files and directories can be copied or created. The
      # contents of this directory will be copied over to the instance before
      # invoking the verifier's run command. After this method completes, it
      # is expected that the contents of the sandbox is complete and ready for
      # copy to the remote instance.
      #
      # **Note:** any subclasses would be well advised to call super first when
      # overriding this method, for example:
      #
      # @example overriding `#create_sandbox`
      #
      #   class MyVerifier < Kitchen::Verifier::Base
      #     def create_sandbox
      #       super
      #       # any further file copies, preparations, etc.
      #     end
      #   end
      def create_sandbox
        super
        prepare_powershell_modules
        prepare_pester_tests
        prepare_helpers
      end

      # Generates a command string which will install and configure the
      # verifier software on an instance. If no work is required, then `nil`
      # will be returned.
      #
      # @return [String] a command string
      def install_command
        return if local_suite_files.empty?
        return if config[:use_local_pester_module]

        really_wrap_shell_code(install_command_script)
      end

      # Generates a command string which will perform any data initialization
      # or configuration required after the verifier software is installed
      # but before the sandbox has been transferred to the instance. If no work
      # is required, then `nil` will be returned.
      #
      # @return [String] a command string
      def init_command
        restart_winrm_service if config[:restart_winrm]
      end

      # Generates a command string which will perform any commands or
      # configuration required just before the main verifier run command but
      # after the sandbox has been transferred to the instance. If no work is
      # required, then `nil` will be returned.
      #
      # @return [String] a command string
      def prepare_command; end

      # Generates a command string which will invoke the main verifier
      # command on the prepared instance. If no work is required, then `nil`
      # will be returned.
      #
      # @return [String] a command string
      def run_command
        return if local_suite_files.empty?

        really_wrap_shell_code(run_command_script)
      end

      # Download functionality was added to the base verifier behavior after
      # version 2.3.4
      if Gem::Version.new(Kitchen::VERSION) <= Gem::Version.new("2.3.4")
        def call(state)
          super

          download_test_files(state)
        end
      end

      # private
      def run_command_script
        <<-CMD
          Import-Module Pester -Force
          $TestPath = "#{config[:root_path]}"
          $OutputFilePath = $TestPath | Join-Path -ChildPath 'PesterTestResults.xml'

          $result = Invoke-Pester -OutputFile $OutputFilePath -OutputFormat NUnitXml -Path $TestPath -Passthru
          $result | Export-CliXml -Path (Join-Path -Path $TestPath -ChildPath 'result.xml')
          $host.SetShouldExit($result.FailedCount)
        CMD
      end

      def really_wrap_shell_code(code)
        wrap_shell_code(Util.outdent!(use_local_powershell_modules(code)))
      end

      def use_local_powershell_modules(script)
        <<-EOH
          set-executionpolicy unrestricted -force;
          $global:ProgressPreference = 'SilentlyContinue'
          $env:psmodulepath += ";$(join-path (resolve-path $env:temp).path 'verifier/modules')"
          #{script}
        EOH
      end

      def install_command_script
        <<-EOH
          [Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
          function directory($path){
            if (test-path $path) {(resolve-path $path).providerpath}
            else {(resolve-path (mkdir $path)).providerpath}
          }
          $VerifierModulePath = directory $env:temp/verifier/modules
          $VerifierTestsPath = directory $env:temp/verifier/pester

    $env:psmodulepath += ";$VerifierModulePath"
          function test-module($module){
            (get-module $module -list) -ne $null
          }
          if (-not (test-module pester)) {
            if (test-module PowerShellGet){
              import-module PowerShellGet -force
              import-module PackageManagement -force
              get-packageprovider -name NuGet -force | out-null
              install-module Pester -force
            }
            else {
              if (-not (test-module PsGet)){
              $wc = New-Object -TypeName Net.WebClient

              if($env:http_Proxy){
                if($env:no_proxy){
                  Write-Output "Creating WebProxy with 'http_proxy' and 'no_proxy' environment variables.
                    $webproxy = New-Object System.Net.WebProxy($env:http_Proxy,$true,$env:no_proxy)
                    }else{
                  Write-Output "Creating WebProxy with 'http_proxy' environment variable.
                  $webproxy = New-Object -TypeName System.Net.WebProxy -ArgumentList ($env:http_Proxy)
                }

                $wc.proxy = $webproxy
              }

              Invoke-Expression -Command $wc.DownloadString('http://bit.ly/GetPsGet')
              }
              try {
                import-module psget -force -erroraction stop
                Install-Module Pester
              }
              catch {
                Write-Output "Installing from Github"
                $zipfile = join-path(resolve-path "$env:temp/verifier") "pester.zip"
                if (-not (test-path $zipfile)){
                  $source = 'https://github.com/pester/Pester/archive/3.3.14.zip'
                  $wc = New-Object -TypeName Net.WebClient

                  if($env:http_Proxy){
                    if($env:no_proxy){
                      Write-Output "Creating WebProxy with 'http_proxy' and 'no_proxy' environment variables."
                      $webproxy = New-Object System.Net.WebProxy($env:http_Proxy,$true,$env:no_proxy)
                    }else{
                      Write-Output "Creating WebProxy with 'http_proxy' environment variable."
                      $webproxy = New-Object -TypeName System.Net.WebProxy -ArgumentList ($env:http_Proxy)
                    }

                  $wc.proxy = $webproxy
                  }

                  [byte[]]$bytes = $wc.DownloadData($source)
                  [IO.File]::WriteAllBytes($zipfile, $bytes)
                  $bytes = $null
                  [gc]::collect()
                  write-output "Downloaded Pester.zip"
                }
                write-output "Creating Shell.Application COM object"
                $shellcom = new-object -com shell.application
                Write-Output "Creating COM object for zip file."
                $zipcomobject = $shellcom.namespace($zipfile)
                Write-Output "Creating COM object for module destination."
                $destination = $shellcom.namespace($VerifierModulePath)
                Write-Output "Unpacking zip file."
                $destination.CopyHere($zipcomobject.Items(), 0x610)
                rename-item (join-path $VerifierModulePath "Pester-3.3.14") -newname 'Pester' -force
              }
            }
          }
          if (-not (test-module Pester)) {
            throw "Unable to install Pester.  Please include Pester in your base image or install during your converge."
          }
        EOH
      end

      def restart_winrm_service
        cmd = "schtasks /Create /TN restart_winrm /TR " \
              '"powershell -command restart-service winrm" ' \
              "/SC ONCE /ST 00:00 "
        wrap_shell_code(Util.outdent!(<<-CMD
          #{cmd}
          schtasks /RUN /TN restart_winrm
        CMD
                                     ))
      end

      def download_test_files(state)
        info("Downloading test result files from #{instance.to_str}")

        instance.transport.connection(state) do |conn|
          config[:downloads].to_h.each do |remotes, local|
            debug("Downloading #{Array(remotes).join(", ")} to #{local}")

            remotes.each do |file|
              safe_name = instance.name.gsub(/[^0-9A-Z-]/i, "_")
              local_path = File.join(local, safe_name, file)
              remote_path = File.join(config[:root_path], file)

              conn.download(remote_path, local_path)
            end
          end
        end

        debug("Finished downloading test result files from #{instance.to_str}")
      end

      # Returns an Array of test suite filenames for the related suite currently
      # residing on the local workstation. Any special provisioner-specific
      # directories (such as a Chef roles/ directory) are excluded.
      #
      # @return [Array<String>] array of suite files
      # @api private

      def suite_test_folder
        @suite_test_folder ||= File.join(test_folder, config[:suite_name])
      end

      def suite_level_glob
        Dir.glob(File.join(suite_test_folder, "*"))
      end

      def suite_verifier_level_glob
        Dir.glob(File.join(suite_test_folder, "*/**/*"))
      end

      def local_suite_files
        suite = suite_level_glob
        suite_verifier = suite_verifier_level_glob
        (suite << suite_verifier).flatten!.reject do |f|
          File.directory?(f)
        end
      end

      def sandboxify_path(path)
        File.join(sandbox_path, path.sub(%r{#{suite_test_folder}/}i, ""))
      end

      # Returns an Array of common helper filenames currently residing on the
      # local workstation.
      #
      # @return [Array<String>] array of helper files
      # @api private
      def helper_files
        glob = Dir.glob(File.join(test_folder, "helpers", "*/**/*"))
        glob.reject { |f| File.directory?(f) }
      end

      # Copies all common testing helper files into the suites directory in
      # the sandbox.
      #
      # @api private
      def prepare_helpers
        base = File.join(test_folder, "helpers")

        helper_files.each do |src|
          dest = File.join(sandbox_path, src.sub("#{base}/", ""))
          debug("Copying #{src} to #{dest}")
          FileUtils.mkdir_p(File.dirname(dest))
          FileUtils.cp(src, dest, preserve: true)
        end
      end

      # Copies all test suite files into the suites directory in the sandbox.
      #
      # @api private
      def prepare_pester_tests
        info("Preparing to copy files from #{suite_test_folder} to the SUT.")

        local_suite_files.each do |src|
          dest = sandboxify_path(src)
          debug("Copying #{src} to #{dest}")
          FileUtils.mkdir_p(File.dirname(dest))
          FileUtils.cp(src, dest, preserve: true)
        end
      end

      def prepare_powershell_module(name)
        FileUtils.mkdir_p(File.join(sandbox_path, "modules/#{name}"))
        FileUtils.cp(
          File.join(File.dirname(__FILE__), "../../support/powershell/#{name}/#{name}.psm1"),
          File.join(sandbox_path, "modules/#{name}/#{name}.psm1"),
          preserve: true
        )
      end

      def prepare_powershell_modules
        info("Preparing to copy supporting powershell modules.")
        %w{PesterUtil}.each do |module_name|
          prepare_powershell_module module_name
        end
      end

      def test_folder
        return config[:test_base_path] if config[:test_folder].nil?

        absolute_test_folder
      end

      def absolute_test_folder
        path = (Pathname.new config[:test_folder]).realpath
        integration_path = File.join(path, "integration")
        return path unless Dir.exist?(integration_path)

        integration_path
      end

    end
  end
end