+ require 'xml/libxml'
+ set_table_name 'current_segments'
+
+ validates_presence_of :user_id, :timestamp
+ validates_inclusion_of :visible, :in => [ true, false ]
+ validates_numericality_of :node_a, :node_b
+
+ has_many :old_segments, :foreign_key => :id
+ belongs_to :user
+
+ # using belongs_to :foreign_key = 'node_*', since if use has_one :foreign_key = 'id', segment preconditions? fails checking for segment id in node table
+ belongs_to :from_node, :class_name => 'Node', :foreign_key => 'node_a'
+ belongs_to :to_node, :class_name => 'Node', :foreign_key => 'node_b'
+
+ def self.from_xml(xml, create=false)
+ begin
+ p = XML::Parser.new
+ p.string = xml
+ doc = p.parse
+
+ segment = Segment.new
+
+ doc.find('//osm/segment').each do |pt|
+ segment.node_a = pt['from'].to_i
+ segment.node_b = pt['to'].to_i
+
+ unless create
+ if pt['id'] != '0'
+ segment.id = pt['id'].to_i
+ end
+ end
+
+ segment.visible = true
+
+ if create
+ segment.timestamp = Time.now
+ else
+ if pt['timestamp']
+ segment.timestamp = Time.parse(pt['timestamp'])
+ end
+ end
+
+ tags = []
+
+ pt.find('tag').each do |tag|
+ tags << [tag['k'],tag['v']]
+ end
+
+ tags = tags.collect { |k,v| "#{k}=#{v}" }.join(';')
+ tags = '' if tags.nil?
+
+ segment.tags = tags
+ end
+ rescue
+ segment = nil
+ end
+
+ return segment
+ end
+
+ def save_with_history!
+ Segment.transaction do
+ self.timestamp = Time.now
+ self.save!
+ old_segment = OldSegment.from_segment(self)
+ old_segment.save!
+ end
+ end
+
+ def to_xml
+ doc = OSM::API.new.get_xml_doc
+ doc.root << to_xml_node()
+ return doc
+ end
+
+ def to_xml_node(user_display_name_cache = nil)
+ el1 = XML::Node.new 'segment'
+ el1['id'] = self.id.to_s
+ el1['from'] = self.node_a.to_s
+ el1['to'] = self.node_b.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?
+
+ Segment.split_tags(el1, self.tags)
+ el1['visible'] = self.visible.to_s
+ el1['timestamp'] = self.timestamp.xmlschema
+ return el1
+ end
+
+ def self.split_tags(el, tags)
+ tags.split(';').each do |tag|
+ parts = tag.split('=')
+ key = ''
+ val = ''
+ key = parts[0].strip unless parts[0].nil?
+ val = parts[1].strip unless parts[1].nil?
+ if key != '' && val != ''
+ el2 = XML::Node.new('tag')
+ el2['k'] = key.to_s
+ el2['v'] = val.to_s
+ el << el2
+ end
+ end
+ end
+
+ def preconditions_ok?
+ from_node and from_node.visible and to_node and to_node.visible
+ end
+