index.js

"use strict";
exports.__esModule = true;
exports.newStore = void 0;
//@ts-check
var react_1 = require("react");
function cloneDeep(obj) {
    return JSON.parse(JSON.stringify(obj));
}
function isEqual(a, b) {
    if (typeof a != typeof b) {
        return false;
    }
    if (typeof a == 'object' && typeof b == 'object') {
        if (Object.keys(a).length != Object.keys(b).length)
            return false;
    }
    return JSON.stringify(a) == JSON.stringify(b);
}
function newStore(state) {
    //@ts-ignore
    var Store = state;
    var callbacks = {};
    var callbacksNextAvailableKey = 0;
    function updateStoreNow() {
        scheduled = false;
        for (var i in callbacks) {
            callbacks[i]();
        }
    }
    var scheduled = false;
    function Schedule() {
        if (scheduled)
            return;
        scheduled = true;
        setTimeout(updateStoreNow, 0);
    }
    /**
     * @example useRerenderIfChange((store) => [store.scale, store.othervalue])
     * @param callback {(store:Store)=>void}
     */
    Store.useRerenderIfChange = function (callback) {
        var _a = (0, react_1.useState)(0), _ = _a[0], setMeToRerender = _a[1];
        var callbacksKeyRef = (0, react_1.useRef)(callbacksNextAvailableKey++);
        /** The array from the user. Cloned so new changes will not be there */
        var cloned = (0, react_1.useCallback)(function () { return cloneDeep(callback(Store)); });
        var lastValueRef = (0, react_1.useRef)(cloned);
        (0, react_1.useEffect)(function () {
            // When object mount, add a function to the callbacks, to change if the value changes
            // it will trigged by the "updateStore below"
            callbacks[callbacksKeyRef.current] = function () {
                var currentValue = callback(Store); // The new array of values calculated from the store
                if (!isEqual(currentValue, lastValueRef.current)) {
                    lastValueRef.current = cloneDeep(currentValue); // Update the old array.
                    setMeToRerender(function (prev) { return prev + 1; }); // Rerender the objects
                }
            };
            return function () {
                // When object unmount we don't need this callback any more.
                delete callbacks[callbacksKeyRef.current];
            };
        }, []);
        return lastValueRef.current;
    };
    Store.updateStore = function () {
        Schedule();
    };
    return Store;
}
exports.newStore = newStore;