class Node < ActiveRecord::Base
+ require 'xml/libxml'
+
+ include GeoRecord
+
set_table_name 'current_nodes'
+
+ validates_presence_of :user_id, :timestamp
+ validates_inclusion_of :visible, :in => [ true, false ]
+ validates_numericality_of :latitude, :longitude
+ validate :validate_position
+
belongs_to :user
+
+ has_many :old_nodes, :foreign_key => :id
+
+ has_many :way_nodes
+ has_many :ways, :through => :way_nodes
+
+ has_many :old_way_nodes
+ has_many :ways_via_history, :class_name=> "Way", :through => :old_way_nodes, :source => :way
+
+ has_many :containing_relation_members, :class_name => "RelationMember", :as => :member
+ has_many :containing_relations, :class_name => "Relation", :through => :containing_relation_members, :source => :relation, :extend => ObjectFinder
+
+ # Sanity check the latitude and longitude and add an error if it's broken
+ def validate_position
+ errors.add_to_base("Node is not in the world") unless in_world?
+ end
+
+ #
+ # Search for nodes matching tags within bounding_box
+ #
+ # Also adheres to limitations such as within max_number_of_nodes
+ #
+ def self.search(bounding_box, tags = {})
+ min_lon, min_lat, max_lon, max_lat = *bounding_box
+ # @fixme a bit of a hack to search for only visible nodes
+ # couldn't think of another to add to tags condition
+ #conditions_hash = tags.merge({ 'visible' => 1 })
+
+ # using named placeholders http://www.robbyonrails.com/articles/2005/10/21/using-named-placeholders-in-ruby
+ #keys = []
+ #values = {}
+
+ #conditions_hash.each do |key,value|
+ # keys << "#{key} = :#{key}"
+ # values[key.to_sym] = value
+ #end
+ #conditions = keys.join(' AND ')
+
+ find_by_area(min_lat, min_lon, max_lat, max_lon,
+ :conditions => 'visible = 1',
+ :limit => APP_CONFIG['max_number_of_nodes']+1)
+ end
+
+ # Read in xml as text and return it's Node object representation
+ def self.from_xml(xml, create=false)
+ begin
+ p = XML::Parser.new
+ p.string = xml
+ doc = p.parse
+
+ node = Node.new
+
+ doc.find('//osm/node').each do |pt|
+ node.lat = pt['lat'].to_f
+ node.lon = pt['lon'].to_f
+
+ return nil unless node.in_world?
+
+ unless create
+ if pt['id'] != '0'
+ node.id = pt['id'].to_i
+ end
+ end
+
+ node.visible = pt['visible'] and pt['visible'] == 'true'
+
+ if create
+ node.timestamp = Time.now
+ else
+ if pt['timestamp']
+ node.timestamp = Time.parse(pt['timestamp'])
+ end
+ end
+
+ tags = []
+
+ pt.find('tag').each do |tag|
+ tags << [tag['k'],tag['v']]
+ end
+
+ node.tags = Tags.join(tags)
+ end
+ rescue
+ node = nil
+ end
+
+ return node
+ end
+
+ # Save this node with the appropriate OldNode object to represent it's history.
+ def save_with_history!
+ Node.transaction do
+ self.timestamp = Time.now
+ self.save!
+ old_node = OldNode.from_node(self)
+ old_node.save!
+ end
+ end
+
+ # Turn this Node in to a complete OSM XML object with <osm> wrapper
+ def to_xml
+ doc = OSM::API.new.get_xml_doc
+ doc.root << to_xml_node()
+ return doc
+ end
+
+ # Turn this Node in to an XML Node without the <osm> wrapper.
+ def to_xml_node(user_display_name_cache = nil)
+ el1 = XML::Node.new 'node'
+ el1['id'] = self.id.to_s
+ el1['lat'] = self.lat.to_s
+ el1['lon'] = self.lon.to_s
+
+ user_display_name_cache = {} if user_display_name_cache.nil?
+
+ if user_display_name_cache and user_display_name_cache.key?(self.user_id)
+ # use the cache if available
+ elsif self.user.data_public?
+ user_display_name_cache[self.user_id] = self.user.display_name
+ else
+ user_display_name_cache[self.user_id] = nil
+ end
+
+ el1['user'] = user_display_name_cache[self.user_id] unless user_display_name_cache[self.user_id].nil?
+
+ Tags.split(self.tags) do |k,v|
+ el2 = XML::Node.new('tag')
+ el2['k'] = k.to_s
+ el2['v'] = v.to_s
+ el1 << el2
+ end
+
+ el1['visible'] = self.visible.to_s
+ el1['timestamp'] = self.timestamp.xmlschema
+ return el1
+ end
+
+ # Return the node's tags as a Hash of keys and their values
+ def tags_as_hash
+ hash = {}
+ Tags.split(self.tags) do |k,v|
+ hash[k] = v
+ end
+ hash
+ end
end