module Terraspace::Compiler
  class Cleaner
    def initialize(mod, options={})
      @mod, @options = mod, options
    end

    def clean
      return if ENV['TS_CLEAN'] == '0'
      backend_change_purge
      remove_materialized_artifacts
      # remove_materialized_artifacts_dot_terraform
      remove_empty_directories
    end

    def backend_change_purge
      BackendChange.new(@mod, @options).purge
    end

    # only remove .tf* files. leaving cache .terraform and terraform.state files
    def remove_materialized_artifacts
      Dir.glob("#{Terraspace.cache_root}/**/*").each do |path|
        next unless within_env?(path)
        next if path.include?(".tfstate")
        FileUtils.rm_f(path) if File.file?(path)
      end
    end

    # Tricky: Reason we remove these artifacts is because they get written to the same source location.
    # So when `terraspace build` is ran twice. The 2nd run will pick up the artifacts and process those again.
    #
    # Comment out for now. Running twice doesnt hurt because it just uses the pass.rb strategy and just copies
    # the file again. With verbose logging, it shows it twice so that's a little bit confusing though.
    #
    # def remove_materialized_artifacts_dot_terraform
    #   expr = "#{@mod.cache_dir}/.terraform/**/*"
    #
    #   Dir.glob(expr).each do |path|
    #     logger.info "path #{path}"
    #   end
    # end

    def remove_empty_directories
      return unless File.exist?(Terraspace.cache_root)
      Dir["#{Terraspace.cache_root}/**/"].reverse_each do |d|
        next unless within_env?(d)
        Dir.rmdir(d) if Dir.entries(d).size == 2
      end
    end

    # Only remove files within an env for the TFC VCS-Workflow.
    # We dont want to run:
    #
    #      TS_ENV=prod terraspace up demo
    #
    # And that to delete the .terraspace-cache/us-west-2/dev files
    #
    # May need to allow further customization to this if user project has a stack named the same as the env.
    #
    def within_env?(path)
      path.include?("/#{Terraspace.env}/")
    end
  end
end