_initSnap: function()

in harness/app-assets/templates/assets/js/components/iscroll.js [1124:1232]
90 lines of code
20 McCabe index (conditional complexity)

	_initSnap: function () {
		this.currentPage = {};

		if ( typeof this.options.snap == 'string' ) {
			this.options.snap = this.scroller.querySelectorAll(this.options.snap);
		}

		this.on('refresh', function () {
			var i = 0, l,
				m = 0, n,
				cx, cy,
				x = 0, y,
				stepX = this.options.snapStepX || this.wrapperWidth,
				stepY = this.options.snapStepY || this.wrapperHeight,
				el;

			this.pages = [];

			if ( !this.wrapperWidth || !this.wrapperHeight || !this.scrollerWidth || !this.scrollerHeight ) {
				return;
			}

			if ( this.options.snap === true ) {
				cx = Math.round( stepX / 2 );
				cy = Math.round( stepY / 2 );

				while ( x > -this.scrollerWidth ) {
					this.pages[i] = [];
					l = 0;
					y = 0;

					while ( y > -this.scrollerHeight ) {
						this.pages[i][l] = {
							x: Math.max(x, this.maxScrollX),
							y: Math.max(y, this.maxScrollY),
							width: stepX,
							height: stepY,
							cx: x - cx,
							cy: y - cy
						};

						y -= stepY;
						l++;
					}

					x -= stepX;
					i++;
				}
			} else {
				el = this.options.snap;
				l = el.length;
				n = -1;

				for ( ; i < l; i++ ) {
					if ( i === 0 || el[i].offsetLeft <= el[i-1].offsetLeft ) {
						m = 0;
						n++;
					}

					if ( !this.pages[m] ) {
						this.pages[m] = [];
					}

					x = Math.max(-el[i].offsetLeft, this.maxScrollX);
					y = Math.max(-el[i].offsetTop, this.maxScrollY);
					cx = x - Math.round(el[i].offsetWidth / 2);
					cy = y - Math.round(el[i].offsetHeight / 2);

					this.pages[m][n] = {
						x: x,
						y: y,
						width: el[i].offsetWidth,
						height: el[i].offsetHeight,
						cx: cx,
						cy: cy
					};

					if ( x > this.maxScrollX ) {
						m++;
					}
				}
			}

			this.goToPage(this.currentPage.pageX || 0, this.currentPage.pageY || 0, 0);

			// Update snap threshold if needed
			if ( this.options.snapThreshold % 1 === 0 ) {
				this.snapThresholdX = this.options.snapThreshold;
				this.snapThresholdY = this.options.snapThreshold;
			} else {
				this.snapThresholdX = Math.round(this.pages[this.currentPage.pageX][this.currentPage.pageY].width * this.options.snapThreshold);
				this.snapThresholdY = Math.round(this.pages[this.currentPage.pageX][this.currentPage.pageY].height * this.options.snapThreshold);
			}
		});

		this.on('flick', function () {
			var time = this.options.snapSpeed || Math.max(
					Math.max(
						Math.min(Math.abs(this.x - this.startX), 1000),
						Math.min(Math.abs(this.y - this.startY), 1000)
					), 300);

			this.goToPage(
				this.currentPage.pageX + this.directionX,
				this.currentPage.pageY + this.directionY,
				time
			);
		});
	},