define ['angular', 'lodash', 'imageSequence'], (ng, _) ->
  registration = ng.module 'qiprofile.registration', ['qiprofile.imagesequence'] 

  registration.factory 'Registration', ['ImageSequence', (ImageSequence) ->
    # Extends the given registration object as follows:
    # * Adds the scan parent reference property
    # * Adds the ImageSequence properties
    # * Sets the registration number
    # * Adds the title and session virtual properties
    #
    # @param registration the registration to extend
    # @param scan the source scan
    # @param number the one-based registration number within the scan
    # @returns the extended registration object
    extend: (registration, scan, number) ->
      # Add the general image sequence properties.
      ImageSequence.extend(registration)
      # Add the parent scan reference.
      registration.scan = scan
      # Add the registration number.
      registration.number = number
      # Add the virtual properties.
      Object.defineProperties registration,
        # @returns the display title
        title:
          get: ->
            "#{ @scan.title } Registration #{ @number }"

        # Returns the <parent>/session path, where:
        # * <parent> is the parent scan path
        # * *registration* is the registration number
        #
        # @returns the registration path
        path:
          get: ->
            "#{ @scan.path }/reg/#{ @number }"

        # An ImageSequence present a uniform interface, which
        # includes a bolus arrival index and session reference.
        #
        # @returns the registration scan session
        session:
          get: -> @scan.session

        # @returns the registration scan bolus arrival
        bolusArrivalIndex:
          get: -> @scan.bolusArrivalIndex
      
      # Return the extended object.
      registration

    # @param scan the Scan object to search
    # @param number the registration number within the scan
    # @returns the scan object
    # @throws ReferenceError if the session does not have the scan
    find: (scan, number) ->
      # Match on the registration number.
      match = (reg) -> reg.number is number
      target = _.find(scan.registrations, match)
      # If no such registration, then complain.
      if not target?
        throw new ReferenceError(
          "#{ scan.title } does not have a registration with number" +
          " #{ number }"
        )

      # Return the scan.
      target
  ]