+ ##
+ # updates the changeset bounding box to contain the bounding box of
+ # the element with given +type+ and +id+. this only works with nodes
+ # and ways at the moment, as they're the only elements to respond to
+ # the :bbox call.
+ def update_changeset_element(type, id)
+ element = Kernel.const_get(type.capitalize).find(id)
+ changeset.update_bbox! element.bbox
+ end
+
+ def delete_with_history!(new_relation, user)
+ unless self.visible
+ raise OSM::APIAlreadyDeletedError.new
+ end
+
+ # need to start the transaction here, so that the database can
+ # provide repeatable reads for the used-by checks. this means it
+ # shouldn't be possible to get race conditions.
+ Relation.transaction do
+ check_consistency(self, new_relation, user)
+ # This will check to see if this relation is used by another relation
+ if RelationMember.find(:first, :joins => "INNER JOIN current_relations ON current_relations.id=current_relation_members.id", :conditions => [ "visible = ? AND member_type='relation' and member_id=? ", true, self.id ])
+ raise OSM::APIPreconditionFailedError.new("The relation #{new_relation.id} is a used in another relation")
+ end
+ self.changeset_id = new_relation.changeset_id
+ self.tags = {}
+ self.members = []
+ self.visible = false
+ save_with_history!
+ end
+ end
+
+ def update_from(new_relation, user)
+ check_consistency(self, new_relation, user)
+ if !new_relation.preconditions_ok?
+ raise OSM::APIPreconditionFailedError.new
+ end
+ self.changeset_id = new_relation.changeset_id
+ self.tags = new_relation.tags
+ self.members = new_relation.members
+ self.visible = true
+ save_with_history!
+ end
+
+ def create_with_history(user)
+ check_create_consistency(self, user)
+ if !self.preconditions_ok?
+ raise OSM::APIPreconditionFailedError.new
+ end
+ self.version = 0
+ self.visible = true
+ save_with_history!
+ end
+
+ def preconditions_ok?
+ # These are hastables that store an id in the index of all
+ # the nodes/way/relations that have already been added.
+ # If the member is valid and visible then we add it to the
+ # relevant hash table, with the value true as a cache.
+ # Thus if you have nodes with the ids of 50 and 1 already in the
+ # relation, then the hash table nodes would contain:
+ # => {50=>true, 1=>true}
+ elements = { :node => Hash.new, :way => Hash.new, :relation => Hash.new }
+ self.members.each do |m|
+ # find the hash for the element type or die
+ hash = elements[m[0].to_sym] or return false
+
+ # unless its in the cache already
+ unless hash.key? m[1]
+ # use reflection to look up the appropriate class
+ model = Kernel.const_get(m[0].capitalize)
+
+ # get the element with that ID
+ element = model.find(m[1])
+
+ # and check that it is OK to use.
+ unless element and element.visible? and element.preconditions_ok?
+ return false
+ end
+ hash[m[1]] = true
+ end
+ end
+
+ return true
+ rescue
+ return false
+ end
+
+ # Temporary method to match interface to nodes
+ def tags_as_hash
+ return self.tags
+ end
+
+ ##
+ # if any members are referenced by placeholder IDs (i.e: negative) then
+ # this calling this method will fix them using the map from placeholders
+ # to IDs +id_map+.
+ def fix_placeholders!(id_map)
+ self.members.map! do |type, id, role|
+ old_id = id.to_i
+ if old_id < 0
+ new_id = id_map[type.to_sym][old_id]
+ raise "invalid placeholder" if new_id.nil?
+ [type, new_id, role]
+ else
+ [type, id, role]
+ end
+ end
+ end
+
+ private
+
projects / rails.git / blobdiff