util.ts

import { Pathname } from '@cycle/history';
import { LocationDescriptorObject } from 'history';

function splitPath(path: Pathname): Pathname[] {
    if (!path) {
        return [];
    }
    return path.split('/').filter(p => p.length > 0);
}

function filterPath(pathParts: Pathname[], namespace: Pathname[]): Pathname {
    return pathParts.filter(part => namespace.indexOf(part) < 0).join('/');
}

const startsWith = (param: string, value: string) => param[0] === value;

const startsWith2 = (param: string, value1: string, value2: string) =>
    param[0] === value1 && param[1] === value2;

function makeCreateHref(
    namespace: Pathname[],
    _createHref: (pathname: LocationDescriptorObject) => Pathname
) {
    /**
     * Function used to create HREFs that are properly namespaced
     * @typedef {createHref}
     * @name createHref
     * @method createHref
     * @param  {string} path - the HREF that will be appended to the current
     * namespace
     * @return {string} a fully qualified HREF composed from the current
     * namespace and the path provided
     */
    return function createHref(
        location: Pathname | LocationDescriptorObject
    ): Pathname {
        if (typeof location === 'object' && location !== null) {
            const fullPath = `${namespace.join('/')}${location.pathname}`;
            return startsWith(fullPath, '/') || startsWith2(fullPath, '#', '/')
                ? _createHref({
                      ...location,
                      pathname: fullPath
                  })
                : _createHref({
                      ...location,
                      pathname: '/' + fullPath
                  });
        } else if (typeof location === 'string') {
            const fullPath = `${namespace.join('/')}${location}`;
            return startsWith(fullPath, '/') || startsWith2(fullPath, '#', '/')
                ? _createHref({
                      pathname: fullPath
                  })
                : _createHref({
                      pathname: '/' + fullPath
                  });
        }
    };
}

export { splitPath, filterPath, makeCreateHref };