+ if node_ids.length > 50_000
+ report_error("You requested too many nodes (limit is 50,000). Either request a smaller area, or use planet.osm")
+ end
+
+ if node_ids.length == 0
+ render :text => "<osm version='0.4'></osm>"
+ return
+ end
+
+ # grab the segments
+ segments = Array.new
+ if node_ids.length > 0
+ node_ids_sql = "(#{node_ids.join(',')})"
+ # get the referenced segments
+ segments = Segment.find_by_sql "select * from current_segments where visible = 1 and (node_a in #{node_ids_sql} or node_b in #{node_ids_sql})"
+ end
+ # see if we have any missing nodes
+ segments_nodes = segments.collect {|segment| segment.node_a }
+ segments_nodes += segments.collect {|segment| segment.node_b }
+
+ segments_nodes.uniq!
+
+ missing_nodes = segments_nodes - node_ids
+
+ # get missing nodes if there are any
+ nodes += Node.find(missing_nodes) if missing_nodes.length > 0
+
+ doc = OSM::API.new.get_xml_doc
+
+ # get ways
+ # find which ways are needed
+ segment_ids = segments.collect {|segment| segment.id }
+ ways = Array.new
+ if segment_ids.length > 0
+ way_segments = WaySegment.find_all_by_segment_id(segment_ids)
+ way_ids = way_segments.collect {|way_segment| way_segment.id }
+ ways = Way.find(way_ids) # NB: doesn't pick up segments, tags from db until accessed via way.way_segments etc.
+
+ # seg_ids = way_segments.collect {|way_segment| way_segment.segment_id }
+
+ list_of_way_segs = ways.collect {|way| way.way_segments}
+ list_of_way_segs.flatten!
+
+ list_of_way_segments = list_of_way_segs.collect { |way_seg| way_seg.segment_id }
+
+ else
+ list_of_way_segments = Array.new
+ end
+
+ # - [0] in case some thing links to segment 0 which doesn't exist. Shouldn't actually ever happen but it does. FIXME: file a ticket for this
+ segments_to_fetch = (list_of_way_segments.uniq - segment_ids) - [0]
+
+ if segments_to_fetch.length > 0
+ segments += Segment.find(segments_to_fetch)
+ end
+
+ # get more nodes
+ #
+
+ segments_nodes = segments.collect {|segment| segment.node_a }
+ segments_nodes += segments.collect {|segment| segment.node_b }
+
+ node_ids_a = nodes.collect {|node| node.id }
+
+ nodes_to_get = segments_nodes - node_ids_a
+ nodes += Node.find(nodes_to_get) if nodes_to_get.length > 0
+
+ visible_nodes = {}
+ user_display_name_cache = {}
+
+ nodes.each do |node|
+ if node.visible?
+ doc.root << node.to_xml_node(user_display_name_cache)
+ visible_nodes[node.id] = node
+ end
+ end
+
+ visible_segments = {}
+
+ segments.each do |segment|
+ if visible_nodes[segment.node_a] and visible_nodes[segment.node_b] and segment.visible?
+ doc.root << segment.to_xml_node(user_display_name_cache)
+ visible_segments[segment.id] = segment
+ end
+ end
+
+ ways.each do |way|
+ doc.root << way.to_xml_node(visible_segments, user_display_name_cache) if way.visible?
+ end
+
+ render :text => doc.to_s
+
+ #exit when we have too many requests
+ if @@count > MAX_COUNT
+ @@count = COUNT
+
+ exit!
+ end
+
+ end