CrowdHailer/Hammerhead2

/* global Hammerhead, _, bean, SVGroovy, missingCTM, requestAnimationFrame, cancelAnimationFrame*/

(function(parent){
    'use strict';
    //cumin compose map map
    // limit zoom
    // round pixels

    var transformObject = function(matrixString){
        return {
            '-webkit-transform': matrixString,
            '-ms-transform': matrixString,
            'transform': matrixString
        };
    };

    var Pt = SVGroovy.Point,
        Mx = SVGroovy.Matrix,
        VB = parent.ViewBox,
        xBtransform = _.compose(transformObject, Mx.asCss3d);

    parent.managePosition = function(){
        var $element = this.$element,
            element = this.element,
            properFix = missingCTM($element), // windows FIX
            viewBox = VB($element.attr('viewBox')),
            animationLoop,
            currentMatrix;

        function renderCSS(){
            if (!animationLoop) {
                animationLoop = requestAnimationFrame(function(){
                    $element.css(xBtransform(currentMatrix));
                    animationLoop = false;
                });
            }
        }

        function renderViewBox(){
            cancelAnimationFrame(animationLoop);
            animationLoop = false;
            requestAnimationFrame(function(){
                $element.css(xBtransform());
                $element.attr('viewBox', VB.attrString(VB.zoom(0.5)()(viewBox)));
            });
        }

        bean.on(element, 'displace', function(point){
            currentMatrix = Mx.toTranslate(point);
            renderCSS();
        });

        bean.on(element, 'inflate', function(scaleFactor){
            currentMatrix = Mx.toScale(scaleFactor);
            renderCSS();
        });

        bean.on(element, 'translate', function(delta){
            properFix = window.missingCTM($element);
            properFix = 1;
            var fixedTranslation = Pt.scalar(properFix)(delta);
            var inverseCTM = $element[0].getScreenCTM().inverse();
            inverseCTM.e = 0;
            inverseCTM.f = 0;
            var scaleTo = Pt.matrixTransform(inverseCTM);
            var svgTrans = scaleTo(fixedTranslation);
            viewBox = VB.translate(svgTrans)(viewBox);
            renderViewBox();
        });

        bean.on(element, 'magnify', function(scale){
            viewBox = VB.zoom(scale)()(viewBox);
            renderViewBox();
        });

        bean.on(element, 'goTo', function(data) {
            viewBox = data;
            renderViewBox();
        });

        $element.css(xBtransform());
        $element.attr('viewBox', VB.attrString(VB.zoom(0.5)()(viewBox)));

        return function(){
            bean.off(element);
        };
    };
}(Hammerhead));