function IncResize()

{

	this.content;

	this.top;

	this.middle;

	this.middleContainer;

	this.bottom;

	this.footer;

	this.minTopBottomHeight;

	this.ratio;

	this.considerFooterToCenter;

	this.callbacks;

	this.init = function(contentId, topId, middleId, bottomId, footerId, minTopBottomHeight, ratio, considerFooterToCenter, callbacks)

	{

		// Content

		this.content = $('#' + contentId);

		// Top

		if (topId != null) {

			this.top = $('#' + topId); 			

		}

		// Middle

		this.middle = $('#' + middleId); 

		this.middleContainer = $(this.middle).parent();

		// Bottom

		if (bottomId !== null) {

			this.bottom = $('#' + bottomId);

		}

		// Footer

		if (footerId !== null) {

			this.footer =  $('#' + footerId);

		}

		this.minTopBottomHeight = minTopBottomHeight;

		this.ratio = ratio;

		this.considerFooterToCenter = (considerFooterToCenter === undefined || footerId === null) ? false : considerFooterToCenter;

		this.callbacks = callbacks;

		$(window).resize(this.resizeElements);

		window.onorientationchange = function() {

			incResize.resizeElements();

		}

	};

	this.resizeElements = function()

	{

		var self = incResize;

		// Compute maximun middle element height

		var heightForTopMiddleBottom = $(self.content).height();

		if (self.footer !== undefined) {

			heightForTopMiddleBottom -= $(self.footer).height()			

		}

		var maxMiddleHeight = heightForTopMiddleBottom - self.minTopBottomHeight * 2;

		// Get the middle element parent width and test if it is not to big (to let place for top and bottom without adding scroll bars)

		var middleRatio = 1 / self.ratio;

		var newMiddleWidth = $(self.middleContainer).width();

		var newMiddleHeight = newMiddleWidth * middleRatio;

		if (self.top !== undefined && self.bottom !== undefined && newMiddleHeight > maxMiddleHeight) {

			newMiddleHeight = maxMiddleHeight;

			newMiddleWidth = newMiddleHeight * 1 / middleRatio;

		}

		newMiddleWidth = Math.max(newMiddleWidth, 1);

		newMiddleHeight = Math.max(newMiddleHeight, 1);

		// Change middle element size and the height of its parent

		$(self.middle).attr('width', newMiddleWidth);

		$(self.middle).attr('height', newMiddleHeight);

		$(self.middleContainer).attr('width', newMiddleWidth);

		$(self.middleContainer).attr('height', newMiddleHeight);

		// Change children size of the middle element

		var children = $(self.middle).children();

		if (children.length > 0) {

			children.attr('width', newMiddleWidth);

			children.attr('height', newMiddleHeight);

		}

		// Post register the middle element size change

		if (self.callbacks !== undefined) {

			for (var i = 0; i < self.callbacks.length; ++i) {

				self.callbacks[i](newMiddleWidth, newMiddleHeight);				

			}

		}

		// Change top and bottom heights

		if (self.top !== undefined && self.bottom !== undefined) {

			// Get the full height and compute heigth for top and bottom

			var remainingHeight = heightForTopMiddleBottom - newMiddleHeight;

			var newTopHeight = remainingHeight / 2.0;

			if (newTopHeight < self.minTopBottomHeight) {

				newTopHeight = self.minTopBottomHeight;

			}

			var newBottomHeight = newTopHeight;

			if (self.considerFooterToCenter) {

				var halfFooterHeight = $(self.footer).height() / 2;

				newTopHeight += halfFooterHeight;

				newBottomHeight -= halfFooterHeight;

			}

			$(self.top).css({"height" : + newTopHeight +'px', "lineHeight" : + newTopHeight + 'px'});

			$(self.bottom).css({"height" : + newBottomHeight + 'px', "lineHeight" : + newBottomHeight + 'px'});					

		}

	};

}

var incResize = new IncResize();