analytics/webcontent/bi/js/gemini/dashboard/widgets/staticwidget/ScalingUtil.js

'use strict';

/**
 * Licensed Materials - Property of IBM
 * IBM Cognos Products: BI Cloud (C) Copyright IBM Corp. 2014
 * US Government Users Restricted Rights - Use, duplication or disclosure restricted by GSA ADP Schedule Contract with IBM Corp.
 */
define(['jquery'], function ($) {
	var ScalingUtil = {
		/**
  * @param params An object with the following members:
  *	*	width and height - the user inputed width and height to scale/
  *		verify
  *	*	image - a Javascript Image object whose width and height are to
  *		be scaled - either width and height, or image must be provided
  *	*	defaultDim - (optional) default dimensions to replace missing
  *		or invalid width/height dimensions
  *	*	scaleWidth - (optional) indicates the width should be replaced
  *		with a version scaled to match the height. This member should
  *		be an object with width and height members indicating the
  *		correct aspect ratio.
  *	*	scaleHeight - (optional) the equivalent of scaleWidth to set
  *		the height. Either scaleWidth or scaleHeight should be
  *		specified, not both.
  *	*	min - (optional) indicates minimum output dimensions. This
  *		member should be an object with width and height members
  *		indicating their respective minimum dimensions.
  *	*	max - (optional) the equivalent of min with the maximum
  *		dimensions. If both min and max are specified, and it is not
  *		possible to satisfy both, max has priority.
  *	*	format - (optional) set to "css" for the outputs to be strings
  *		with "px"; otherwise they will be integers.
  *	@return an object with width and height members
  */
		scale: function scale(params) {
			var dim = {
				width: params.width,
				height: params.height
			};
			var aspectRatio;

			if (!dim.width && !dim.height && params.image) {
				dim.width = params.image.naturalWidth;
				dim.height = params.image.naturalHeight;
			}

			dim.width = this._sanitizeNumberInput(dim.width);
			dim.height = this._sanitizeNumberInput(dim.height);

			if (params.defaultDim) {
				if (dim.width < 1 && !params.scaleWidth) {
					dim.width = params.defaultDim.width;
				}
				if (dim.height < 1 && !params.scaleHeight) {
					dim.height = params.defaultDim.height;
				}
			}

			this._applyScale(params.scaleWidth || params.scaleHeight, !!params.scaleWidth, dim);

			aspectRatio = dim.width / dim.height;

			this._enforceMin(params.min, aspectRatio, dim);
			this._enforceMax(params.max, aspectRatio, dim);

			this._formatDimens(params.format, dim);
			return dim;
		},

		// returns input as an integer if it is numeric, otherwise return input
		_sanitizeNumberInput: function _sanitizeNumberInput(input) {
			var number = 0;
			if ($.type(input) === 'number') {
				number = input;
			} else if ($.isNumeric(input)) {
				number = parseInt(input, 10);
			}
			return number;
		},

		// applies scale to dim
		// if dim doesn't have a value, overwrites it with scale
		_applyScale: function _applyScale(scale, scaleWidth, dim) {
			if (scale) {
				var wScale = scale.width;
				var hScale = scale.height;
				var bothSet = dim.width > 0 && dim.height > 0;

				if (dim.width < 1 && dim.height < 1) {
					dim.width = wScale;
					dim.height = hScale;
				} else {
					this._scaleMaintainRatio(scale, scaleWidth, bothSet, dim);
				}
			}
		},

		// scales dim to have the same aspect ratio as scale
		// if force=true, will overwrite previous value, otherwise it will keep previous value
		// if scaleWidth=true, modifies width, otherwise modifies height
		// precondition: dim has at least one of width/height defined
		_scaleMaintainRatio: function _scaleMaintainRatio(scale, scaleWidth, force, dim) {
			if (scaleWidth && (dim.width < 1 || force)) {
				dim.width = scale.width * dim.height / scale.height;
			} else if (!scaleWidth && (dim.height < 1 || force)) {
				dim.height = scale.height * dim.width / scale.width;
			}
		},

		// enforces min dimensions while preserving aspect ratio
		_enforceMin: function _enforceMin(min, aspectRatio, dim) {
			if (min) {
				var wMin = min.width;
				var hMin = min.height;
				var wRatio = wMin ? dim.width / wMin : 1;
				var hRatio = hMin ? dim.height / hMin : 1;

				if (wRatio < 1 && wRatio < hRatio) {
					dim.width = wMin;
					dim.height = wMin / aspectRatio;
				} else if (hRatio < 1) {
					dim.height = hMin;
					dim.width = hMin * aspectRatio;
				}
			}
		},

		// enforces max dimensions while preserving aspect ratio
		_enforceMax: function _enforceMax(max, aspectRatio, dim) {
			if (max) {
				var wMax = max.width;
				var hMax = max.height;
				var wRatio = wMax ? dim.width / wMax : 0;
				var hRatio = hMax ? dim.height / hMax : 0;

				if (wRatio > 1 && wRatio > hRatio) {
					dim.width = wMax;
					dim.height = wMax / aspectRatio;
				} else if (hRatio > 1) {
					dim.height = hMax;
					dim.width = hMax * aspectRatio;
				}
			}
		},

		// formats dimensions by rounding them and changing to css styles if format=css
		_formatDimens: function _formatDimens(format, dim) {
			dim.width = Math.round(dim.width);
			dim.height = Math.round(dim.height);
			if (format === 'css') {
				dim.width = dim.width + 'px';
				dim.height = dim.height + 'px';
			}
		}
	};

	return ScalingUtil;
});
//# sourceMappingURL=ScalingUtil.js.map