# Reader - fgdc to internal data structure
# unpack fgdc map projection - polar stereographic

# History:
#  Stan Smith 2018-10-03 refactor mdJson projection object
#  Stan Smith 2017-10-17 original script

require 'nokogiri'
require 'adiwg/mdtranslator/internal/internal_metadata_obj'
require_relative 'projection_common'

module ADIWG
   module Mdtranslator
      module Readers
         module Fgdc

            module PolarStereoProjection

               def self.unpack(xParams, hProjection, hResponseObj)

                  # map projection 4.1.2.1.15 (polarst) - Polar Stereographic
                  unless xParams.empty?
                     paramCount = 0

                     # -> ReferenceSystemParameters.projection.straightVerticalLongitudeFromPole
                     paramCount += ProjectionCommon.unpackVSLong(xParams, hProjection)

                     # -> [ standardParallel1 | scaleFactorAtProjectionOrigin ]
                     # -> ReferenceSystemParameters.projection.standardParallel1
                     paramCount += ProjectionCommon.unpackStandParallel(xParams, hProjection)

                     # -> ReferenceSystemParameters.projection.scaleFactorAtProjectionOrigin
                     paramCount += ProjectionCommon.unpackSFPO(xParams, hProjection)

                     # -> ReferenceSystemParameters.projection.latitudeOfProjectionCenter
                     paramCount += ProjectionCommon.unpackLatPC(xParams, hProjection)

                     # -> ReferenceSystemParameters.projection.falseEasting
                     # -> ReferenceSystemParameters.projection.falseNorthing
                     paramCount += ProjectionCommon.unpackFalseNE(xParams, hProjection)

                     # verify parameter count
                     if paramCount == 4
                        return hProjection
                     else
                        hResponseObj[:readerExecutionMessages] <<
                           'WARNING: FGDC reader: Polar Stereographic projection is missing one or more parameters'
                     end
                  end

                  return nil

               end

            end

         end
      end
   end
end