# encoding: UTF-8
#/* - - - - - - - - - - - - - - - - - - - - -
#
#   Title : WEB Appliances Crest Inc, Web Form Framework
#   Author : Enrique Phillips
#   URL : http://www.wac.bz
#
#- - - - - - - - - - - - - - - - - - - - - */
# the <b>PrintEngine</b> module ...

# TODO build the print_engine as a Gem
# http://rarlindseysmash.com/posts/config-and-generators-in-gems
#


#
module PrintEngine

  include Exceptions

  def self.included(base)

    #
    # find the best printer for the job
    def base.default_printer usr, printer_name, paper=nil
      if printer_name=="default"
        if paper.nil?
          printer = (usr.printers.empty? ? nil : usr.printers.active.preferred_printer.first) or raise NoPreferredPrintersFound.new('No preferred printers were found!')
        else
          printer = (usr.printers.empty? ? nil : (usr.printers.active.preferred_printer.on_paper(paper).first || usr.printers.on_paper(paper).first ) ) or raise NoPreferredPrintersFound.new('No preferred printers were found!')
        end
      else
        printer = Printer.active.find_by( 'name like ?',  "%#{printer_name.downcase}%")
      end
      # usr.printers.where{ (printownerables.preferred==true) & (printownerables.preferred==true) }

      # raise PrintJobPrinterNotAvailableError
      printer || Printer.first
    # rescue
    #   Printer.new
    end

    #
    # def base.default_print_template_path(params,usr)
    #   # TODO 2013-09-02 - select template according to the user/employee
    #   params[:print_job][:view_template_path] || "/test.html.haml"
    # end

    # Creates the PrintJob for any model in need of printing
    # If creating the PrintJob is successful, cycle will be called in print_job.rb
    # and the PrintJob will be enqueued in the delayed_job queue called 'printing'.
    # cycle_error will be called in print_job.rb if it cannot be enqueued sucessfully.
    def base.print( resources, params )
      begin
        pj = create_print_job( resources, params )
        return false unless pj
      rescue PrintJobResourceError
        base.logit :error, 'PrintJob could not be created - no records!?'
        return false

      rescue PrintJobPrinterNotAvailableError
        logit :error, 'PrintJob could not be created - the user has no printers attached!!'
        return false
      end

      begin
        if Rails.env=='development' or pj.download
          return pj if pj.perform params
        else
          user = User.find(pj.printed_by_id)
          BackgroundPrinterJob.perform_later pj, queue: "printing", account_id: user.account.id
          # Delayed::Job.enqueue pj, :queue => 'printing'
          # pj.cycle if Delayed::Job.enqueue pj, :queue => 'printing'
          # If you comment out above line and use below line with pj.perform instead, you thereby surpass delayed_job, and thus don't have to wait for it
          # pj.perform
          return pj
        end
      rescue => e
        # self.logit :error, 'PrintJob could not be enqueued'
        pj.update_columns( state: "could not be queued for printing - #{e}" )
        return nil
      end
    end

    #
    #
    def base.create_print_job( resources, params )
      printer_name = params.delete(:printer_name) || "default"
      params = ActionController::Parameters.new( params) unless params.class == ActionController::Parameters
      params = set_print_job_defaults(resources,params, printer_name)
      return nil if params[:print_job][:printer_id].nil?
      PrintJob.create( params[:print_job].permit(:download, :snap_shot, :account_id, :printer_id, :printed_by_id, :printed_by_type, :view_template_path, :name, :printing_class, :print_driver, :print_format, :paper, :copies, :state, :print_sql) )
    end

    # Sets print_job defaults using the provided params
    # and looks up any print_job settings to be tweaked
    # as per klass and user
    def base.set_print_job_defaults(resources, params, printer_name)
      klass = resources.first.class.to_s rescue "class not found!"
      params[:print_job] ||= {}
      params[:user] ||= User.first
      user = params[:user]
      params[:print_job][:account_id]           ||= user.account.id
      params[:print_job][:paper]                ||= nil
      params[:print_job][:printer_id]           ||= self.default_printer(user,printer_name,params[:print_job][:paper]).id
      params[:print_job][:printed_by_id]        = user.id
      params[:print_job][:printed_by_type]      = user.class.to_s
      params[:print_job][:name]                 ||= "#{klass} print at #{I18n.l Time.now, format: :short_date }"
      params[:print_job][:printing_class]       ||= klass
      params[:print_job][:print_driver]         ||= :pdf
      params[:print_job][:copies]               ||= 1
      params[:print_job][:print_format]         ||= "list"
      params[:print_job][:state]                = "drafted"
      params[:print_job][:snap_shot]            ||= false
      params[:print_job][:print_sql]            = set_resource_sql(resources,params)

      # this is what we ultimately return
      params
    end

    def base.set_resource_sql(resources,params)
      return resources if resources.class == String && resources.downcase =~ /select/
      raise PrintJobResourceError unless resources.respond_to?(:any?) and resources.any?
      params[:print_job][:snap_shot] ? resources.to_yaml : (resources.class==Array ? array_to_arel(resources) : resources.to_sql)
    end

    def base.array_to_arel resources
      arel_instance = Arel::Table.new(resources.first.class.table_name)
      ar_rel = resources.first.class
      ar_rel.where(arel_instance[:id].in(resources.map(&:id)).to_sql).to_sql
    end

  end

end