+# == Schema Information
+#
+# Table name: changesets
+#
+# id :bigint(8) not null, primary key
+# user_id :bigint(8) not null
+# created_at :datetime not null
+# min_lat :integer
+# max_lat :integer
+# min_lon :integer
+# max_lon :integer
+# closed_at :datetime not null
+# num_changes :integer default(0), not null
+#
+# Indexes
+#
+# changesets_bbox_idx (min_lat,max_lat,min_lon,max_lon) USING gist
+# changesets_closed_at_idx (closed_at)
+# changesets_created_at_idx (created_at)
+# changesets_user_id_created_at_idx (user_id,created_at)
+# changesets_user_id_id_idx (user_id,id)
+#
+# Foreign Keys
+#
+# changesets_user_id_fkey (user_id => users.id)
+#
+
+class Changeset < ApplicationRecord
+ require "xml/libxml"
+
+ belongs_to :user, :counter_cache => true
+
+ has_many :changeset_tags
+
+ has_many :nodes
+ has_many :ways
+ has_many :relations
+ has_many :old_nodes
+ has_many :old_ways
+ has_many :old_relations
+
+ has_many :comments, -> { where(:visible => true).order(:created_at) }, :class_name => "ChangesetComment"
+ has_and_belongs_to_many :subscribers, :class_name => "User", :join_table => "changesets_subscribers", :association_foreign_key => "subscriber_id"
+
+ validates :id, :uniqueness => true, :presence => { :on => :update },
+ :numericality => { :on => :update, :only_integer => true }
+ validates :user_id, :presence => true,
+ :numericality => { :only_integer => true }
+ validates :num_changes, :presence => true,
+ :numericality => { :only_integer => true,
+ :greater_than_or_equal_to => 0 }
+ validates :created_at, :closed_at, :presence => true
+ validates :min_lat, :max_lat, :min_lon, :max_lat, :allow_nil => true,
+ :numericality => { :only_integer => true }
+
+ before_save :update_closed_at
+
+ # maximum number of elements allowed in a changeset
+ MAX_ELEMENTS = 10000
+
+ # maximum time a changeset is allowed to be open for.
+ MAX_TIME_OPEN = 1.day
+
+ # idle timeout increment, one hour seems reasonable.
+ IDLE_TIMEOUT = 1.hour
+
+ # Use a method like this, so that we can easily change how we
+ # determine whether a changeset is open, without breaking code in at
+ # least 6 controllers
+ def is_open?
+ # a changeset is open (that is, it will accept further changes) when
+ # it has not yet run out of time and its capacity is small enough.
+ # note that this may not be a hard limit - due to timing changes and
+ # concurrency it is possible that some changesets may be slightly
+ # longer than strictly allowed or have slightly more changes in them.
+ ((closed_at > Time.now.getutc) && (num_changes <= MAX_ELEMENTS))
+ end