Function _getSwapDirection

src/Sortable.js:1832–1901

(evt, target, targetRect, vertical, swapThreshold, invertedSwapThreshold, invertSwap, isLastTarget)

}

function _getSwapDirection(evt, target, targetRect, vertical, swapThreshold, invertedSwapThreshold, invertSwap, isLastTarget) {
	let mouseOnAxis = vertical ? evt.clientY : evt.clientX,
		targetLength = vertical ? targetRect.height : targetRect.width,
		targetS1 = vertical ? targetRect.top : targetRect.left,
		targetS2 = vertical ? targetRect.bottom : targetRect.right,
		invert = false;


	if (!invertSwap) {
		// Never invert or create dragEl shadow when target movemenet causes mouse to move past the end of regular swapThreshold
		if (isLastTarget && targetMoveDistance < targetLength * swapThreshold) { // multiplied only by swapThreshold because mouse will already be inside target by (1 - threshold) * targetLength / 2
			// check if past first invert threshold on side opposite of lastDirection
			if (!pastFirstInvertThresh &&
				(lastDirection === 1 ?
					(
						mouseOnAxis > targetS1 + targetLength * invertedSwapThreshold / 2
					) :
					(
						mouseOnAxis < targetS2 - targetLength * invertedSwapThreshold / 2
					)
				)
			)
			{
				// past first invert threshold, do not restrict inverted threshold to dragEl shadow
				pastFirstInvertThresh = true;
			}

			if (!pastFirstInvertThresh) {
				// dragEl shadow (target move distance shadow)
				if (
					lastDirection === 1 ?
					(
						mouseOnAxis < targetS1 + targetMoveDistance // over dragEl shadow
					) :
					(
						mouseOnAxis > targetS2 - targetMoveDistance
					)
				)
				{
					return -lastDirection;
				}
			} else {
				invert = true;
			}
		} else {
			// Regular
			if (
				mouseOnAxis > targetS1 + (targetLength * (1 - swapThreshold) / 2) &&
				mouseOnAxis < targetS2 - (targetLength * (1 - swapThreshold) / 2)
			) {
				return _getInsertDirection(target);
			}
		}
	}

	invert = invert || invertSwap;

	if (invert) {