ResponsiveImagesController

define ["underscore"], (_) ->
	class ResponsiveImagesController
		currImgSize: "small"
		breakpoint: 480
		constructor: (@images) ->
			@debouncedHandleResize = _.debounce( @handleResize, 500 )
			@bindEvents()
			@handleResize()
		bindEvents: ->
			$(window).on( "resize.responsive-images", @debouncedHandleResize )
		handleResize: =>
			w = window.innerWidth
			if w < @breakpoint and @currImgSize isnt "small"
				@currImgSize = "small"
				@updateImageSrc()
			else if w >= @breakpoint and @currImgSize isnt "large"
				@currImgSize = "large"
				@updateImageSrc()
		updateImageSrc: ->
			targetSrc = if @currImgSize is "small" then "data-src" else "data-src-lg"
			@images.each -> @setAttribute( "src", @getAttribute targetSrc )
			$(document).trigger( "vh/update_responsive_images", [@currImgSize] )