Layout junk

layout.js

/******************************************************************************
  Copyright (c) 2011 Noel R. Cower
    
  Permission is hereby granted, free of charge, to any person obtaining a copy
  of this software and associated documentation files (the "Software"), to deal
  in the Software without restriction, including without limitation the rights
  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  copies of the Software, and to permit persons to whom the Software is
  furnished to do so, subject to the following conditions:
    
  The above copyright notice and this permission notice shall be included in
  all copies or substantial portions of the Software.
    
  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  THE SOFTWARE.
******************************************************************************/

(function (ns, $, undefined) {
	"use strict";
	
	// makes an element occupy the same space horizontally or vertically as its base
	ns.kConstraintFillHorizontal       = 0;	// same as aligning left and right edges to a single base
	ns.kConstraintFillVertical         = 1;	// same as aligning top and bottom edges to a single base
	// align element edges to base edges (basically elem.edge = base.edge)
	ns.kConstraintAlignTop             = 2;
	ns.kConstraintAlignBottom          = 3;
	ns.kConstraintAlignLeft            = 4;
	ns.kConstraintAlignRight           = 5;
	// aligns an element's edge to the middle of the base (left/right = horizontal, top/bottom = vertical)
	ns.kConstraintCenterTop            = 6;
	ns.kConstraintCenterBottom         = 7;
	ns.kConstraintCenterLeft           = 8;
	ns.kConstraintCenterRight          = 9;
	// places an element next to its base
	ns.kConstraintPutBelow                = 10;
	ns.kConstraintPutAbove                = 11;
	ns.kConstraintPutLeftOf               = 12;
	ns.kConstraintPutRightOf              = 13;
	// centers an element relative to its base
	// these constraints modify two edges at a time
	ns.kConstraintCenterVertical       = 14;
	ns.kConstraintCenterHorizontal     = 15;
	
	var kLayoutFunctions = [
		// kConstraintFillHorizontal
		function (elemq, baseq, elemPos, basePos, mods, margin) {
			mods.leftSet = true;
			mods.rightSet = true;
			elemPos.left = basePos.left + margin;
			elemq.offset(elemPos).width(baseq.width() - (margin * 2));
		},
		 // kConstraintFillVertical
		function (elemq, baseq, elemPos, basePos, mods, margin) {
			mods.topSet = true;
			mods.bottomSet = true;
			elemPos.top = basePos.top + margin;
			elemq.offset(elemPos).height(baseq.height() - (margin * 2));
		},
		
		// kConstraintAlignTop
		function (elemq, baseq, elemPos, basePos, mods, margin) {
			if (mods.bottomSet) {
				var bottom = elemPos.top + elemq.height();
				elemPos.top = basePos.top + margin;
				elemq.offset(elemPos).height(bottom - elemPos.top);
			} else {
				elemPos.top = basePos.top;
				elemq.offset(elemPos);
			}
						
			mods.topSet = true;
		},
		
		// kConstraintAlignBottom
		function (elemq, baseq, elemPos, basePos, mods, margin) {
			if (mods.topSet) {
				elemq.height((basePos.top + baseq.height()) - elemPos.top - margin);
			} else {
				elemPos.top = (basePos.top + baseq.height()) - elemq.height() - margin;
				elemq.offset(elemPos);
			}
						
			mods.bottomSet = true;
		},
		
		// kConstraintAlignLeft
		function (elemq, baseq, elemPos, basePos, mods, margin) {
			if (mods.rightSet) {
				var right = elemPos.left + elemq.width();
				elemPos.left = basePos.left + margin;
				elemq.offset(elemPos).width(right - elemPos.left);
			} else {
				elemPos.left = basePos.left + margin;
				elemq.offset(elemPos);
			}
						
			mods.leftSet = true;
		},
		
		// kConstraintAlignRight
		function (elemq, baseq, elemPos, basePos, mods, margin) {
			if (mods.leftSet) {
				elemq.width((basePos.left + baseq.width()) - elemPos.left - margin);
			} else {
				elemPos.left = (basePos.left + baseq.width()) - elemq.width() - margin;
				elemq.offset(elemPos);
			}
						
			mods.rightSet = true;
		},
		
		// kConstraintCenterTop
		function (elemq, baseq, elemPos, basePos, mods, margin) {
			var middle = (basePos.top + (baseq.height() * 0.5)) + margin;
			
			if (mods.bottomSet) {
				var bottom = elemPos.top + elemq.height();
				elemPos.top = middle;
				elemq.offset(elemPos).height(bottom - middle);
			} else {
				elemPos.top = middle;
				elemq.offset(elemPos);
			}
			
			mods.topSet = true;
		},
		
		// kConstraintCenterBottom
		function (elemq, baseq, elemPos, basePos, mods, margin) {
			var middle = (basePos.top + (baseq.height() * 0.5)) - margin;
			
			if (mods.topSet) {
				elemq.height(middle - elemPos.top);
			} else {
				elemPos.top = middle - elemq.height();
				elemq.offset(elemPos);
			}
						
			mods.bottomSet = true;
		},
		
		// kConstraintCenterLeft
		function (elemq, baseq, elemPos, basePos, mods, margin) {
			var middle = (basePos.left + (baseq.width() * 0.5)) + margin;
			
			if (mods.rightSet) {
				var right = elemPos.left + elemq.width();
				elemPos.left = middle;
				elemq.offset(elemPos).width(right - middle);
			} else {
				elemPos.left = middle;
				elemq.offset(elemPos);
			}
			
			mods.leftSet = true;
		},
		
		// kConstraintCenterRight
		function (elemq, baseq, elemPos, basePos, mods, margin) {
			var middle = (basePos.left + (baseq.width() * 0.5)) - margin;
			
			if (mods.topSet) {
				elemq.width(middle - elemPos.left);
			} else {
				elemPos.left = middle - elemq.width();
				elemq.offset(elemPos);
			}
						
			mods.rightSet = true;
		},
		
		// kConstraintPutBelow
		function (elemq, baseq, elemPos, basePos, mods, margin) {
			var y = (basePos.top + baseq.height()) + margin;
			
			if (mods.bottomSet) {
				var bottom = elemPos.top + elemq.height();
				elemPos.top = y;
				elemq.offset(elemPos).height(bottom - y);
			} else {
				elemPos.top = y;
				elemq.offset(elemPos);
			}
						
			mods.topSet = true;
		},
		
		// kConstraintPutAbove
		function (elemq, baseq, elemPos, basePos, mods, margin) {
			var bottomEdge = basePos.top - margin;
			
			if (mods.topSet) {
				elemq.height(bottomEdge - elemPos.top);
			} else {
				elemPos.top = bottomEdge - elemq.height();
				elemq.offset(elemPos);
			}
			
			mods.bottomSet = true;
		},
		
		// kConstraintPutLeftOf
		function (elemq, baseq, elemPos, basePos, mods, margin) {
			var right = basePos.top - margin;
			
			if (mods.leftSet) {
				elemq.height(right - elemPos.left);
			} else {
				elemPos.top = right - elemq.width();
				elemq.offset(elemPos);
			}
			
			mods.rightSet = true;
			
		},
		
		// kConstraintPutRightOf
		function (elemq, baseq, elemPos, basePos, mods, margin) {
			var x = (basePos.left + baseq.width()) + margin;
			
			if (mods.rightSet) {
				var right = elemPos.left + elemq.width();
				elemPos.left = x;
				elemq.offset(elemPos).width(right - x);
			} else {
				elemPos.left = x;
				elemq.offset(elemPos);
			}
						
			mods.leftSet = true;
		},
		
		// kConstraintCenterVertical
		function (elemq, baseq, elemPos, basePos, mods, margin) {
			elemPos.top = basePos.top + ((baseq.height() - elemq.height()) * 0.5) + margin;
			mods.topSet = true;
			mods.bottomSet = true;
			elemq.offset(elemPos);
		},
		
		// kConstraintCenterHorizontal
		function (elemq, baseq, elemPos, basePos, mods, margin) {
			elemPos.left = basePos.left + ((baseq.width() - elemq.width()) * 0.5) + margin;
			mods.leftSet = true;
			mods.rightSet = true;
			elemq.offset(elemPos);
		}
	];
	
	// modification set
	
	/*@ Generates modification sets for all elements in the constraints list */
	var ElemModSet = function(constraints) {
		var mods = {}
		
		constraints.forEach(function (constraint, index, arr) {
				$(constraint.element).each(function (index, elem) {
					if (mods[elem] != undefined)
						return;
				
					mods[elem] = {
						topSet: false,
						bottomSet: false,
						leftSet: false,
						rightSet: false
					};
				});
			});
		
		this.mods = mods
	};
	
	/*@ Gets the modifications set for a given element */
	ElemModSet.prototype.setForElement = function(elem) {
		return this.mods[elem];
	};
	
	
	// constraint container

	/*@
		Creates a constraint for `domElement` with a given `relation` to `domBase`.
		Optionally specifies an inset `margin` (negative values are outset), defaults
		to 0.
	*/
	ns.Constraint = function(domElement, relation, domBase, margin) {
		if (margin == undefined) margin = 0;
		
		this.element = domElement;
		this.relation = relation;
		this.base = domBase;
		this.margin = margin;
	};
	
	
	// layout manager
	
	/*@ Creates a layout manager */
	ns.LayoutManager = function() {
		this.constraints = [];
	};
	
	/*@ Adds a `constraint` to the list of constraints the `LayoutManager` maintains */
	ns.LayoutManager.prototype.addConstraint = function(constraint) {
		this.constraints.push(constraint);
		return this;
	};
	
	/*@
		Removes one or more constraints from the `LayoutManager`.
		
		Function takes one of three prototypes:
			1. `removeConstraints()` -- removes all constraints from the `LayoutManager`
			2. `removeConstraints(selector)` -- removes all constraints that match the `selector`
			3. `removeConstraints([object1], [object2], ...)` -- removes all constraints that are
				passed, as well as any constraints for DOM elements that are passed.
	*/
	ns.LayoutManager.prototype.removeConstraints = function() {
		if (arguments.length == 0) {
			this.constraints = []
		} else {
			// this could definitely be optimized..
			arguments.forEach(function (arg, index, argsArray) {
				var typ = typeof(arg);
				if (typ == 'string') {
					var elements = $(arg);
					this.constraints = this.constraints.filter(function (constraint, index, array) {
							return (elements.index(constraint.element) == -1);
						}, this);
				} else if (typ == 'object') {
					this.constraints = this.constraints.filter(function (constraint, index, array) {
							return !(constraint == arg || constraint.target == arg);
						}, this);
				}
			}, this);
		}
		return this;
	};
	
	/*@ Causes the `LayoutManager` to layout its views. */
	ns.LayoutManager.prototype.doLayout = function() {
		var constraints = this.constraints;
		var elemMods = new ElemModSet(constraints);
		
		// some terrifying loop-in-loop shit right here
		constraints.forEach( function (constraint, index, constraintsArray) {
				$(constraint.element).each(function(index, elem) {
					var elemq = $(elem);
					var baseq = $(constraint.base);
				
					var elemPos = elemq.offset();
					var basePos = baseq.offset();
				
					var mods = elemMods.setForElement(elem);
				
					kLayoutFunctions[constraint.relation].call(this, elemq, baseq, elemPos, basePos, mods, constraint.margin);
				});
			}, this);
		
		return this;
	};
	
})(window.NLM = window.NLM || {}, jQuery);