# unpack geographic element
# Reader - ADIwg JSON V1 to internal data structure
# determine element type

# History:
# 	Stan Smith 2013-11-04 original script
# 	Stan Smith 2013-11-13 added line string
# 	Stan Smith 2013-11-13 added multi line string
# 	Stan Smith 2013-11-18 added polygon
#   Stan Smith 2014-04-30 complete redesign for json schema 0.3.0
#   Stan Smith 2014-05-22 added multi polygon
#   Stan Smith 2014-05-23 cleaned up hash copy problem by using Marshal
#   Stan Smith 2014-05-23 added direct geometry support for Point, Line, Polygon
#   Stan Smith 2014-05-23 added direct geometry support for MultiPoint, MultiLine, MultiPolygon
#   Stan Smith 2014-05-23 added direct support for geometryCollection
#   Stan Smith 2014-07-07 resolve require statements using Mdtranslator.reader_module

require ADIWG::Mdtranslator.reader_module('module_geoCoordSystem', $response[:readerVersionUsed])
require ADIWG::Mdtranslator.reader_module('module_geoProperties', $response[:readerVersionUsed])
require ADIWG::Mdtranslator.reader_module('module_boundingBox', $response[:readerVersionUsed])
require ADIWG::Mdtranslator.reader_module('module_point', $response[:readerVersionUsed])
require ADIWG::Mdtranslator.reader_module('module_lineString', $response[:readerVersionUsed])
require ADIWG::Mdtranslator.reader_module('module_polygon', $response[:readerVersionUsed])

module Md_GeographicElement

	def self.unpack(aGeoElements)

		# only one geometry is allowed per geographic element.
		# ... in GeoJSON each geometry is allowed a bounding box;
		# ... This code splits bounding boxes to separate elements

		# instance classes needed in script
		aIntGeoEle = Array.new

		aGeoElements.each do |hGeoJsonElement|

			# instance classes needed in script
			intMetadataClass = InternalMetadata.new
			hGeoElement = intMetadataClass.newGeoElement

			# find geographic element type
			if hGeoJsonElement.has_key?('type')
				elementType = hGeoJsonElement['type']
			else
				# invalid geographic element
				return nil
			end

			# set geographic element id
			if hGeoJsonElement.has_key?('id')
				s = hGeoJsonElement['id']
				if s != ''
					hGeoElement[:elementId] = s
				end
			end

			# set geographic element coordinate reference system - CRS
			if hGeoJsonElement.has_key?('crs')
				hGeoCrs = hGeoJsonElement['crs']
				Md_GeoCoordSystem.unpack(hGeoCrs, hGeoElement)
			end

			# set geographic element properties
			if hGeoJsonElement.has_key?('properties')
				hGeoProps = hGeoJsonElement['properties']
				Md_GeoProperties.unpack(hGeoProps, hGeoElement)
			end

			# process geographic element bounding box
			# the bounding box must be represented as a separate geographic element for ISO
			# need to make a deep copy of current state of geographic element for bounding box
			if hGeoJsonElement.has_key?('bbox')
				if hGeoJsonElement['bbox'].length == 4
					aBBox = hGeoJsonElement['bbox']

					boxElement = Marshal.load(Marshal.dump(hGeoElement))
					boxElement[:elementGeometry] = Md_BoundingBox.unpack(aBBox)

					aIntGeoEle << boxElement
				end
			end

			# unpack geographic element
			case elementType

				# GeoJSON Features
				when 'Feature'
					if hGeoJsonElement.has_key?('geometry')
						hGeometry = hGeoJsonElement['geometry']

						# geoJSON requires geometry to be 'null' when geometry is bounding box only
						# JSON null converts in parsing to ruby nil
						unless hGeometry.nil?
							unless hGeometry.empty?
								if hGeometry.has_key?('type')
									geometryType = hGeometry['type']
									aCoordinates = hGeometry['coordinates']
									unless aCoordinates.empty?
										case geometryType
											when 'Point', 'MultiPoint'
												hGeoElement[:elementGeometry] = Md_Point.unpack(aCoordinates, geometryType)
											when 'LineString', 'MultiLineString'
												hGeoElement[:elementGeometry] = Md_LineString.unpack(aCoordinates, geometryType)
											when 'Polygon', 'MultiPolygon'
												hGeoElement[:elementGeometry] = Md_Polygon.unpack(aCoordinates, geometryType)
											else
												# log - the GeoJSON geometry type is not supported
										end
										aIntGeoEle << hGeoElement
									end
								end
							end
						end

					end

				# GeoJSON Feature Collection
				when 'FeatureCollection'
					if hGeoJsonElement.has_key?('features')
						aFeatures = hGeoJsonElement['features']
						unless aFeatures.empty?
							intGeometry = intMetadataClass.newGeometry
							intGeometry[:geoType] = 'MultiGeometry'
							intGeometry[:geometry] = Md_GeographicElement.unpack(aFeatures)
							hGeoElement[:elementGeometry] = intGeometry
							aIntGeoEle << hGeoElement
						end
					end

				# GeoJSON Geometries
				when 'Point', 'MultiPoint'
					aCoordinates = hGeoJsonElement['coordinates']
					hGeoElement[:elementGeometry] = Md_Point.unpack(aCoordinates, elementType)
					aIntGeoEle << hGeoElement

				when 'LineString', 'MultiLineString'
					aCoordinates = hGeoJsonElement['coordinates']
					hGeoElement[:elementGeometry] = Md_LineString.unpack(aCoordinates, elementType)
					aIntGeoEle << hGeoElement

				when 'Polygon', 'MultiPolygon'
					aCoordinates = hGeoJsonElement['coordinates']
					hGeoElement[:elementGeometry] = Md_Polygon.unpack(aCoordinates, elementType)
					aIntGeoEle << hGeoElement

				# GeoJSON Geometry Collection
				when 'GeometryCollection'
					if hGeoJsonElement.has_key?('geometries')
						aGeometries = hGeoJsonElement['geometries']
						unless aGeometries.empty?
							intGeometry = intMetadataClass.newGeometry
							intGeometry[:geoType] = 'MultiGeometry'
							intGeometry[:geometry] = Md_GeographicElement.unpack(aGeometries)
							hGeoElement[:elementGeometry] = intGeometry
							aIntGeoEle << hGeoElement
						end
					end

			end

		end

		return aIntGeoEle

	end

end