function persist()

in public/src/js/utils/drag-dispatcher.js [221:292]
61 lines of code
24 McCabe index (conditional complexity)

function persist (sourceItem, newItems, sourceContext, sourceGroup, targetContext, targetGroup, position, isAfter) {
    if (sourceItem.type === vars.CONST.draggableTypes.configCollection) {
        if (!findFirstById(newItems[0].parents, targetGroup.parent.id())) {
            newItems[0].parents.push(targetGroup.parent.opts);
        }

        return targetGroup.parent.saveProps();
    } else {
        var id = newItems[0].id(),
            itemMeta,
            supporting,
            update,
            remove,
            returnValue;

        if (!targetGroup || !targetGroup.parent) {
            return;

        } else if (targetGroup.parentType === 'Article') {
            supporting = targetGroup.parent.meta.supporting.items;
            _.each(newItems.slice(1), function(item) {
                supporting.remove(function (supp) { return supp.id() === item.id(); });
                supporting.push(item);
            });
            returnValue = capi.decorateItems(supporting());

            remove = remover(sourceContext, sourceGroup, id);

        } else if (targetGroup.parentType === 'Collection') {
            itemMeta = serializeArticleMeta(newItems[0]) || {};

            if (deepGet(targetGroup, '.parent.groups.length') > 1) {
                itemMeta.group = targetGroup.index + '';
            } else {
                delete itemMeta.group;
            }

            update = {
                collection: targetGroup.parent,
                item:     id,
                position: position,
                after:    isAfter,
                mode:     targetContext.mode(),
                itemMeta: _.isEmpty(itemMeta) ? undefined : itemMeta
            };

            remove = sourceGroup && sourceGroup.parentType === 'Collection' && (deepGet(sourceGroup, '.parent.id') && deepGet(sourceGroup, '.parent.id') !== targetGroup.parent.id);
            remove = remove ? remover(sourceContext, sourceGroup, id) : undefined;
        }

        if (sourceContext !== targetContext) {
            remove = false;
        }

        if (update || remove) {
            returnValue = authedAjax.updateCollections({
                update: update,
                remove: remove ? remove : undefined
            })
            .then(function () {
                if (targetContext.mode() === 'live') {
                    mediator.emit('presser:detectfailures', targetContext.front());
                }
            });
        }

        if (remove !== false && sourceGroup && !sourceGroup.keepCopy && sourceGroup !== targetGroup && sourceGroup.items) {
            removeById(sourceGroup.items, id); // for immediate UI effect
        }
        return returnValue;
    }
}