# ISO <<Class>> ConventionalUnit
# 19115-2 writer output in XML

# History:
# 	Stan Smith 2015-08-27 copied from 19110 writer

module ADIWG
   module Mdtranslator
      module Writers
         module Iso19115_2

            class ConventionalUnit

               def initialize(xml, hResponseObj)
                  @xml = xml
                  @hResponseObj = hResponseObj
               end

               def writeXML(hConv)

                  # create and identity for the unit
                  @hResponseObj[:writerMissingIdCount] = @hResponseObj[:writerMissingIdCount].succ
                  unitID = 'unit' + @hResponseObj[:writerMissingIdCount]

                  @xml.tag!('gml:ConventionalUnit', {'gml:id' => unitID}) do
                     @xml.tag!('gml:identifier', {'codeSpace' => hConv[:codeSpace]}, hConv[:identifier])
                     @xml.tag!('gml:name', hConv[:name])
                     @xml.tag!('gml:catalogSymbol', hConv[:catalogSymbol])
                     @xml.tag!('gml:conversionToPreferredUnit', {'uom' => hConv[:preferredUnit]}) do

                        # two methods of conversion are available
                        # factor and formula
                        if !hConv[:factor].nil?
                           # factor:
                           #    y = factor * x
                           #    y is in preferred units
                           #    x is in provided units
                           #    factor is conversion to preferred units
                           @xml.tag!('gml:factor', hConv[:factor])
                        else
                           # formula:
                           #    y = (a + bx) / (c + dx)
                           #    y is in preferred units
                           #    x is in provided units
                           #    a,b,c,d are constants to convert to preferred units
                           @xml.tag!('gml:formula') do
                              @xml.tag!('gml:a', hConv[:a])
                              @xml.tag!('gml:b', hConv[:b])
                              @xml.tag!('gml:c', hConv[:c])
                              @xml.tag!('gml:d', hConv[:d])
                           end
                        end

                     end
                  end

               end

            end

         end
      end
   end
end