merged node and old node models for normalised node tags

app/models/node.rb

@@ -1,5 +1,3 @@
-# The node model represents a current existing node, that is, the latest version. Use OldNode for historical nodes.
-
 class Node < GeoRecord
   require 'xml/libxml'
 
@@ -10,16 +8,21 @@ class Node < GeoRecord
   validates_numericality_of :latitude, :longitude
   validate :validate_position
 
-  has_many :ways, :through => :way_nodes
   has_many :old_nodes, :foreign_key => :id
   has_many :way_nodes
+  has_many :node_tags, :foreign_key => :id
   belongs_to :user
  
-  # 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
 
+  def in_world?
+    return false if self.lat < -90 or self.lat > 90
+    return false if self.lon < -180 or self.lon > 180
+    return true
+  end
+
   #
   # Search for nodes matching tags within bounding_box
   #
@@ -80,10 +83,9 @@ class Node < GeoRecord
         tags = []
 
         pt.find('tag').each do |tag|
-          tags << [tag['k'],tag['v']]
+          node.add_tag_key_val(tag['k'],tag['v'])
         end
 
-        node.tags = Tags.join(tags)
       end
     rescue
       node = nil
@@ -92,24 +94,45 @@ class Node < GeoRecord
     return node
   end
 
-  # Save this node with the appropriate OldNode object to represent it's history.
   def save_with_history!
+    t = Time.now
+
     Node.transaction do 
-      self.timestamp = Time.now
+      # apply timestamp to the new node
+      self.timestamp = t
       self.save!
-      old_node = OldNode.from_node(self)
-      old_node.save!
     end
+
+    # Create a NodeTag
+    NodeTag.transaction do 
+      tags = self.tags
+
+      NodeTag.delete_all(['id = ?', self.id])
+
+      sequence_id = 1
+      tags.each do |k,v|
+        tag = NodeTag.new
+        tag.k = k 
+        tag.v = v 
+        tag.id = self.id
+        tag.sequence_id = sequence_id
+        tag.save!
+        sequence_id += 1
+      end 
+    end 
+    # Create an OldNode
+    old_node = OldNode.from_node(self)
+    old_node.timestamp = t
+    old_node.save_with_dependencies!
+
   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
@@ -128,7 +151,7 @@ class Node < GeoRecord
 
     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|
+    self.tags.each do |k,v|
       el2 = XML::Node.new('tag')
       el2['k'] = k.to_s
       el2['v'] = v.to_s
@@ -140,7 +163,6 @@ class Node < GeoRecord
     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|
@@ -148,4 +170,26 @@ class Node < GeoRecord
     end
     hash
   end
+
+  def tags
+    unless @tags
+      @tags = {}
+      self.node_tags.each do |tag|
+        @tags[tag.k] = tag.v
+      end
+    end
+    @tags
+  end
+
+  def tags=(t)
+    @tags = t 
+  end 
+
+  def add_tag_key_val(k,v)
+    @tags = Hash.new unless @tags
+    @tags[k] = v
+  end
+
+
+
 end

app/models/old_node.rb

@@ -37,7 +37,7 @@ class OldNode < GeoRecord
     el1['lon'] = self.lon.to_s
     el1['user'] = self.user.display_name if self.user.data_public?
 
-    Tags.split(self.tags) do |k,v|
+    self.tags.each do |k,v|
       el2 = XML::Node.new('tag')
       el2['k'] = k.to_s
       el2['v'] = v.to_s
@@ -48,4 +48,41 @@ class OldNode < GeoRecord
     el1['timestamp'] = self.timestamp.xmlschema
     return el1
   end
+
+  def save_with_dependencies!
+    save!
+    #not sure whats going on here
+    clear_aggregation_cache
+    clear_association_cache
+    #ok from here
+    @attributes.update(OldNode.find(:first, :conditions => ['id = ? AND timestamp = ?', self.id, self.timestamp]).instance_variable_get('@attributes'))
+   
+    sequence_id = 1
+    self.tags.each do |k,v|
+      tag = OldNodeTag.new
+      tag.k = k
+      tag.v = v
+      tag.id = self.id
+      tag.version = self.version
+      tag.sequence_id = sequence_id
+      tag.save!
+      sequence_id += 1
+    end
+  end
+
+  def tags
+    unless @tags
+        @tags = Hash.new
+        OldNodeTag.find(:all, :conditions => ["id = ? AND version = ?", self.id, self.version]).each do |tag|
+            @tags[tag.k] = tag.v
+        end
+    end
+    @tags = Hash.new unless @tags
+    @tags
+  end
+
+  def tags=(t)
+    @tags = t 
+  end 
+
 end