qiprofile/app/javascripts/image.coffee

Quantitative Imaging Profile ( QiPr) web application

define ['angular', 'lodash', 'loader', 'imageStore', 'nifti'], (ng, _, Loader) ->
  image = ng.module 'qiprofile.image', ['qiprofile.imagestore', 'qiprofile.nifti']

  image.factory 'Image', ['ImageStore', 'Nifti', (ImageStore, Nifti) ->
    # Matches a NIfTI file extension.
    NIFTI_REGEX = /\.nii(\.gz)?$/

    # An image representation which can load an image file.
    class ImageMixin extends Loader
      parser: ->
        if NIFTI_REGEX.test(@name)
          Nifti
        else
          throw new Error("The image format could not be inferred from" +
                          " the image file extension for file #{ @name }")

      # Loads the image file and parses it with the given parser.
      # This method delegates to Loader.load to load the file
      # and the parser to parse the file.
      #
      # @returns a promise which resolves to this image object
      #   extended with the parsed {header, data} *contents* property
      load: ->
        # The image content parser service.
        parser = @parser()
        # Delegate to the Loader.load function.
        super(this, ImageStore)
          .then (raw) =>
            parser.parse(raw)
          .then (parsed) =>
            @contents = parsed

    Object.defineProperties ImageMixin.prototype,
      # Returns the <parent>/image path, where:
      # * <parent> is the parent scan or registration image
      #   sequence path
      # * *image* is the time series image name
      #
      # @returns the ancestor path
      path:
        get: ->
          # Make and cache the title on demand, since it is
          # potentially called frequently as the basis for
          # an image id.
          if not @_path?
            @_path = "#{ @imageSequence.path }/#{ @resource }/#{ @name }"
          @_path

    # Makes the following changes to the given REST Image object:
    # * adds the generic parent imageSequence reference
    # * adds the concrete parent scan or registration reference
    # * adds the Loader functionality
    #
    # @param image the REST Image object to extend
    # @return the extended Image object
    extend: (image) ->
      # Add the loader functionality.
      _.extend(image, new ImageMixin)
  ]