@ideal-postcodes/postcode-lookup/esm/watch.js

UK Postcode Lookup plugin from Ideal Postcodes

/**
 * @module Watch
 */
import { setup } from "./setup";
import { getScope, getParent, watchChange, toArray, loaded, markLoaded, } from "@ideal-postcodes/jsutil";
const isTrue = () => true;
const NOOP = () => { };
const formScope = (anchor) => getParent(anchor, "FORM");
const getAnchors = (config, marker) => {
    const scope = getScope(config.scope || null);
    const matches = scope.querySelectorAll(config.anchor || config.context || config.scope);
    return toArray(matches).filter((e) => !loaded(e, marker));
};
/**
 * Dynamically apply PostcodeLookup
 * when relevant html configuration appear
 * - Exits if page test is fails
 * - Not binding when context is null or already have controller bound
 * - Use controller bind to build solution
 */
export const watch = (config, options = {}) => {
    const { pageTest = isTrue, onError = NOOP, onBindAttempt = NOOP, onBind = NOOP, anchor, onAnchorFound = NOOP, getScope = formScope, marker = "idpc-pl", } = options;
    let controller;
    const bind = () => {
        try {
            onBindAttempt(config);
            getAnchors({ anchor, ...config }, marker).forEach((anchor) => {
                if (!pageTest())
                    return;
                const scope = getScope(anchor);
                onAnchorFound({ anchor, scope, config });
                controller = setup(config);
                markLoaded(anchor, marker);
                onBind(controller);
            });
        }
        catch (error) {
            onError(error);
        }
    };
    const { start, stop } = watchChange({ bind });
    //start watching changes
    start();
    return { start, stop, controller };
};