dimensions.js

"use strict"

var $ = require("elements")

var relativeMap = {
    right: 'left',
    bottom: 'top'
}

var relativeExclude = ['width', 'height']

$.implement({

    position: function(relative){
        var node = this[0], box = {left: 0, right: 0, top: 0, bottom: 0},
            win = window, doc = node.ownerDocument,
            docElem = doc.documentElement,
            body = doc.body

        if (typeof node.getBoundingClientRect !== "undefined"){
            box = node.getBoundingClientRect()
        }

        var clientTop  = docElem.clientTop  || body.clientTop  || 0,
            clientLeft = docElem.clientLeft || body.clientLeft || 0,
            scrollTop  = win.pageYOffset || docElem.scrollTop,
            scrollLeft = win.pageXOffset || docElem.scrollLeft,
            dx = scrollLeft - clientLeft,
            dy = scrollTop - clientTop

        var pos = {
            x: box.left + dx, left: box.left + dx,
            y: box.top + dy, top: box.top + dy,
            right: box.right + dx, bottom: box.bottom + dy,
            width: box.right - box.left,
            height: box.bottom - box.top
        }

        if (relative && (relative = $(relative))) {
            var rp = relative.position()
            for(var prop in pos){
                if (relativeExclude.indexOf(prop) == -1 ) pos[prop] = pos[prop] - rp[ prop in relativeMap ? relativeMap[prop] : prop ]
            }
        }

        return pos
    }

})

module.exports = $