// @flow
import { type Change } from 'slate';

import type Options from '../options';
import { getItemsAtRange } from '../utils';

/**
 * Unwrap items at range from their list.
 */
function unwrapList(opts: Options, change: Change): Change {
    const items = getItemsAtRange(opts, change.value);

    if (items.isEmpty()) {
        return change;
    }

    // Unwrap the items from their list
    items.forEach(item =>
        change.unwrapNodeByKey(item.key, { normalize: false })
    );

    // Parent of the list of the items
    const firstItem = items.first();
    const parent = change.value.document.getParent(firstItem.key);

    let index = parent.nodes.findIndex(node => node.key === firstItem.key);

    // Unwrap the items' children
    items.forEach(item => {
        item.nodes.forEach(node => {
            change.moveNodeByKey(node.key, parent.key, index, {
                normalize: false
            });
            index += 1;
        });
    });

    // Finally, remove the now empty items
    items.forEach(item =>
        change.removeNodeByKey(item.key, { normalize: false })
    );

    return change;
}

export default unwrapList;