device-navigation/dist/nav-tree/nav-tree.js

Navigate HTML elements in two dimensions with non-pointer devices.

import { check } from '@augment-vir/assert';
import { getOrSet } from '@augment-vir/common';
import { extractNavEntry } from '../directives/nav-entry.js';
/**
 * Maps an `ElementTree` to a {@link NavTree}.
 *
 * @category Internal
 */
export function mapTree(elementTree) {
    const children = mapTreeRecursively(elementTree)?.children || [];
    return {
        root: true,
        children,
    };
}
function mapTreeRecursively(elementTree) {
    const element = elementTree.element;
    if (!(element instanceof HTMLElement)) {
        return undefined;
    }
    const navEntry = extractNavEntry(element);
    const children = expandChildren(elementTree);
    const isValidGroup = navEntry?.navParams.group ? !!children.length : false;
    if (isValidGroup || !!children.length || !!navEntry) {
        return {
            root: false,
            element,
            navEntry,
            children,
        };
    }
    else {
        return undefined;
    }
}
function expandChildren(elementTreeNode) {
    const rawChildren = [];
    function pushNode(node) {
        if (node.navEntry?.navParams.group && !node.children.length) {
            return;
        }
        else if (!node.navEntry) {
            node.children.forEach((row) => row.forEach((child) => pushNode(child)));
            return;
        }
        const x = node.navEntry.navParams.x;
        const y = node.navEntry.navParams.y || 0;
        const row = getOrSet(rawChildren, y, () => {
            return {
                noX: [],
                withX: [],
                y,
            };
        });
        if (x == undefined) {
            row.noX.push(node);
        }
        else {
            row.withX.push({ x, node });
        }
    }
    elementTreeNode.children.forEach((child) => {
        const newNode = mapTreeRecursively(child);
        if (newNode) {
            pushNode(newNode);
        }
    });
    // eslint-disable-next-line sonarjs/no-misleading-array-reverse
    return rawChildren
        .sort((rowA, rowB) => {
        return rowA.y - rowB.y;
    })
        .map((row) => {
        row.withX.sort((a, b) => {
            return a.x - b.x;
        });
        row.withX.forEach(({ x, node }) => {
            row.noX.splice(x, 0, node);
        });
        return row.noX;
    })
        .filter(check.isTruthy);
}