(function(jQuery) {
	function stripFiletype(ref) {
		var x=ref.replace('.html', '');
		return x.replace('#', '');
	}
	
	function initOrigin(l) {
		if(l.xorigin == 'left'){l.xorigin=0;} else if (l.xorigin=='middle' || l.xorigin=='centre' || l.xorigin=='center') {l.xorigin=0.5;} else if (l.xorigin=='right') {l.xorigin=1;}
		if(l.yorigin == 'top'){l.yorigin=0;} else if (l.yorigin=='middle' || l.yorigin=='centre' || l.yorigin=='center') {l.yorigin=0.5;} else if (l.yorigin=='bottom') {l.yorigin=1;}
	}
	
	function positionMouse(mouseport, localmouse, virtualmouse) {
		var difference = {x: 0, y: 0, sum: 0};
		if (!mouseport.ontarget) {
			difference.x = virtualmouse.x - localmouse.x;
			difference.y = virtualmouse.y - localmouse.y;
			difference.sum = Math.sqrt(difference.x*difference.x + difference.y*difference.y);
			virtualmouse.x = localmouse.x + difference.x * mouseport.takeoverFactor;
			virtualmouse.y = localmouse.y + difference.y * mouseport.takeoverFactor;
			if (difference.sum < mouseport.takeoverThresh && difference.sum > mouseport.takeoverThresh*-1) {
				mouseport.ontarget = true;
			}
		} else {
			virtualmouse.x = localmouse.x;
			virtualmouse.y = localmouse.y;
		}
	}
	
	function setupPorts(viewport, mouseport) {
		var offset = mouseport.element.offset();
		jQuery.extend(viewport, {
			width: viewport.element.width(),
			height: viewport.element.height()
		});
		jQuery.extend(mouseport, {
			width: mouseport.element.width(),
			height: mouseport.element.height(),
			top: offset.top,
			left: offset.left
		});
	}
	
	function parseTravel(travel, origin, dimension) {
		var offset;
		var cssPos;
		if (typeof(travel) === 'string') {
			if (travel.search(/px/)) {
				travel = travel.replace('px', '');
				travel = parseInt(travel, 10);
				offset = origin * (dimension-travel);
				cssPos = origin * 100 + '%';
				return {travel: travel, travelpx: true, offset: offset, cssPos: cssPos};
			} else if (travel.search(/%/)) {
				travel.replace('%', '');
				travel = parseInt(ytravel, 10) / 100;
			} else {
				travel=1;
			}
		}
		offset = origin * (1 - travel);
		return {travel: travel, travelpx: false, offset: offset}
	}
	
	function setupLayer(layer, i, mouseport) {
		var xStuff;
		var yStuff;
		var cssObject = {};
		layer[i]=jQuery.extend({}, {
			width: layer[i].element.width(),
			height: layer[i].element.height()
		}, layer[i]);
		xStuff = parseTravel(layer[i].xtravel, layer[i].xorigin, layer[i].width);
		yStuff = parseTravel(layer[i].ytravel, layer[i].yorigin, layer[i].height);
		jQuery.extend(layer[i], {
			// Used in triggerResponse
			diffxrat: mouseport.width / (layer[i].width - mouseport.width),
			diffyrat: mouseport.height / (layer[i].height - mouseport.height),
			// Used in moveLayers
			xtravel: xStuff.travel,
			ytravel: yStuff.travel,
			xtravelpx: xStuff.travelpx,
			ytravelpx: yStuff.travelpx,
			xoffset: xStuff.offset,
			yoffset: yStuff.offset
		});
		
		// Set origin now if it won't be altered in moveLayers()
		if (xStuff.travelpx) {cssObject.left = xStuff.cssPos;}
		if (yStuff.travelpx) {cssObject.top = yStuff.cssPos;}
		if (xStuff.travelpx || yStuff.travelpx) {layer[i].element.css(cssObject);}
	}
	
	function setupLayerContents(layer, i, viewportOffset) {
		
		var contentOffset;
		
		// Give layer a content object
		jQuery.extend(layer[i], {content: []});
		// Layer content: get positions, dimensions and calculate element offsets for centering children of layers
		for (var n=0; n<layer[i].element.children().length; n++) {
			
			if (!layer[i].content[n])          layer[i].content[n]             = {};
			if (!layer[i].content[n].element)  layer[i].content[n]['element']  = layer[i].element.children().eq(n);
			
			// Store the anchor name if one has not already been specified.  You can specify anchors in Layer Options rather than html if you want.
			if(!layer[i].content[n].anchor && layer[i].content[n].element.children('a').attr('name')) {
				layer[i].content[n]['anchor'] = layer[i].content[n].element.children('a').attr('name');
			}
			
			// Only bother to store child's dimensions if child has an anchor.  What's the point otherwise?
			if(layer[i].content[n].anchor) {
				contentOffset = layer[i].content[n].element.offset();
				jQuery.extend(layer[i].content[n], {
					width: layer[i].content[n].element.width(),
					height: layer[i].content[n].element.height(),
					x: contentOffset.left - viewportOffset.left,
					y: contentOffset.top - viewportOffset.top
				});
				jQuery.extend(layer[i].content[n], {
					posxrat: (layer[i].content[n].x + layer[i].content[n].width/2) / layer[i].width,
					posyrat: (layer[i].content[n].y + layer[i].content[n].height/2) / layer[i].height
				});
			}
		}
	}
	
	function moveLayers(layer, xratio, yratio) {
		
		var xpos;
		var ypos;
		var cssObject;
		
		for (var i=0; i<layer.length; i++) {
			// Calculate the moving factor
			xpos = layer[i].xtravel * xratio + layer[i].xoffset;
			ypos = layer[i].ytravel * yratio + layer[i].yoffset;
			cssObject = {};
			// Do the moving by pixels or by ratio depending on travelpx
			if (layer[i].xparallax) {
				if (layer[i].xtravelpx) {
					cssObject.marginLeft = xpos * -1 + 'px';
				} else {
					cssObject.left = xpos * 100 + '%';
					cssObject.marginLeft = xpos * layer[i].width *-1 + 'px';
				}
			}
			if (layer[i].yparallax) {
				if (layer[i].ytravelpx) {
					cssObject.marginTop = ypos * -1 + 'px';
					} else {
					cssObject.top = ypos * 100 + '%';
					cssObject.marginTop = ypos * layer[i].height * -1 + 'px';
				}
			}
			layer[i].element.css(cssObject);
		}
	}
	
	// PLUGIN DEFINITION **********************************************************************
	jQuery.fn.jparallax = function(options) {
		
		// Organise settings into objects (Is this a bit of a mess, or is it efficient?)
		var settings = jQuery().extend({}, jQuery.fn.jparallax.settings, options);
		var settingsLayer = {
			xparallax: settings.xparallax,
			yparallax: settings.yparallax,
			xorigin: settings.xorigin,
			yorigin: settings.yorigin,
			xtravel: settings.xtravel,
			ytravel: settings.ytravel
		};
		var settingsMouseport = {
			element: settings.mouseport,
			takeoverFactor: settings.takeoverFactor,
			takeoverThresh: settings.takeoverThresh
		};
		if (settings.mouseport) settingsMouseport['element'] = settings.mouseport;
		
		// Populate layer array with default settings
		var layersettings = [];
		for(var a=1; a<arguments.length; a++) {
			layersettings.push( jQuery.extend( {}, settingsLayer, arguments[a]) );
		}
		
		// Iterate matched elements
		return this.each(function() {
			
			// VAR
			var localmouse = {
				x: 0.0,
				y: 0.0
			};
			var virtualmouse = {
				x: 0.0,
				y: 0.0
			};
			
			var timer = {
				running: false,
				frame: settings.frameDuration,
				fire: function(x, y) {
					positionMouse(mouseport, localmouse, virtualmouse);
					moveLayers(layer, virtualmouse.x, virtualmouse.y);
					this.running = setTimeout(function() {
						if ( localmouse.x!=x || localmouse.y!=y || !mouseport.ontarget ) {
							timer.fire(localmouse.x, localmouse.y);
						} else if (timer.running) {
							timer.running=false;
						}
					}, timer.frame);
				}
			};
			
			var viewport = {element: jQuery(this)};
			
			var mouseport = jQuery.extend({}, {element: viewport.element}, settingsMouseport, {
				xinside: false, // is the mouse inside the mouseport's dimensions?
				yinside: false,
				active: false, // are the mouse coordinates still being read?
				ontarget: false // is the top layer inside the takeoverThresh?
			});
			
			var layer = [];
			
			// FUNCTIONS
			function matrixSearch(layer, ref, callback) {
				for (var i=0; i<layer.length; i++) {
					var gotcha=false;
					for (var n=0; n<layer[i].content.length; n++) {
						if (layer[i].content[n].anchor==ref) {
							callback(i, n);
							return [i, n];
						}
					}
				}
				return false;
			}
			
			funkyfresh = function (x,y) {
				localmouse.x = x
				localmouse.y = y
				mouseport.ontarget = false
				timer.fire(x,y)
			}
			
			// RUN
			setupPorts(viewport, mouseport);
			
			// Cycle through and create layers
			for (var i=0; i<viewport.element.children().length; i++) {
				// Create layer from settings if it doesn't exist
				layer[i]=jQuery.extend({}, settingsLayer, layersettings[i], {
					element:	viewport.element.children('*:eq('+i+')')
				});
				
				setupLayer(layer, i, mouseport);
				
				if (settings.triggerResponse) {
					setupLayerContents(layer, i, viewport.element.offset());
				}
			}
			
			// Set up layers CSS and initial position
			viewport.element.children().css('position', 'absolute');
			moveLayers(layer, 0.0, 0.0);
			
			// Mouse Response
			if (settings.mouseResponse) {
				jQuery().mousemove(function(mouse){
					// Is mouse inside?
					mouseport.xinside = (mouse.pageX >= mouseport.left && mouse.pageX < mouseport.width+mouseport.left) ? true : false;
					mouseport.yinside = (mouse.pageY >= mouseport.top  && mouse.pageY < mouseport.height+mouseport.top)  ? true : false;
					// Then switch active on.
					if (mouseport.xinside && mouseport.yinside && !mouseport.active) {
						mouseport.ontarget = false;
						mouseport.active = true;
					}
					// If active is on give localmouse coordinates
					if (mouseport.active) {
						if (mouseport.xinside) { localmouse.x = (mouse.pageX - mouseport.left) / mouseport.width; }
						else { localmouse.x = (mouse.pageX < mouseport.left) ? 0 : 1; }
						if (mouseport.yinside) { localmouse.y = (mouse.pageY - mouseport.top) / mouseport.height; }
						else { localmouse.y = (mouse.pageY < mouseport.top) ? 0 : 1; }
					}
					
					// If mouse is inside, fire timer
					if (mouseport.xinside && mouseport.yinside)  { if (!timer.running) timer.fire(localmouse.x, localmouse.y); }
					else if (mouseport.active) { mouseport.active = false; }
				});
			}
			
			var lastY = lastX = 0;
			if(window.DeviceMotionEvent){
				window.ondevicemotion = function(evt){
					var val = evt.accelerationIncludingGravity;
					
					if(window.orientation == 0 || window.orientation == 180){
						localmouse.x = -val.x * 0.2;
						localmouse.y = -val.y * 0.2;
					} else {
						localmouse.x = -val.y * 0.2;
						localmouse.y = -val.x * 0.2;
					}
					
					localmouse.x = (localmouse.x + lastX) / 2;
					localmouse.y = (localmouse.y + lastY) / 2;
					lastX = localmouse.x;
					lastY = localmouse.y;
					
					localmouse.x = Math.round(localmouse.x * 100) / 100;
					localmouse.y = Math.round(localmouse.y * 100) / 100;
					
					timer.fire(localmouse.x, localmouse.y);
				}
			}
				
			// Window Resize Response
			jQuery(window).resize(function() {
				setupPorts(viewport, mouseport);
				for (var i=0; i<layer.length; i++) {
					setupLayer(layer, i, mouseport);
				}
			});
			
			funky_layer = layer
		});
	};
	// END OF PLUGIN DEFINITION **********************************************************************
	
	// PLUGIN DEFAULTS
	jQuery.fn.jparallax.settings = {
		mouseResponse: true,						// Sets mouse response
		triggerResponse: true,					  // Sets trigger response
		triggerExposesEdges: false,          // Sets whether the trigger pulls layer edges into view in trying to centre layer content.
		xparallax: true,						// Sets directions to move in
		yparallax: true,						//
		xorigin: 0.5,				    // Sets default alignment - only comes into play when travel is not 1
		yorigin: 0.5,				    //
		xtravel: 1,              // Factor by which travel is amplified
		ytravel: 1,              //
		takeoverFactor: 0.65,						// Sets rate of decay curve for catching up with target mouse position
		takeoverThresh: 0.002,					// Sets the distance within which virtualmouse is considered to be on target, as a multiple of mouseport width.
		frameDuration: 25							// In milliseconds
	};
	
	// RUN
	initOrigin(jQuery.fn.jparallax.settings);
	
})(jQuery);