@platform/state/lib/Store/Store.js

A small, simple, strongly typed, [rx/observable] state-machine.

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.Store = void 0;
var tslib_1 = require("tslib");
var immer_1 = require("immer");
var rxjs_1 = require("rxjs");
var operators_1 = require("rxjs/operators");
var Store = (function () {
    function Store(args) {
        var _this = this;
        this._dispose$ = new rxjs_1.Subject();
        this._changing$ = new rxjs_1.Subject();
        this._changed$ = new rxjs_1.Subject();
        this._ = {
            state: undefined,
        };
        this.dispose$ = this._dispose$.pipe((0, operators_1.share)());
        this.changing$ = this._changing$.pipe((0, operators_1.share)());
        this.changed$ = this._changed$.pipe((0, operators_1.share)());
        this._.state = tslib_1.__assign({}, args.initial);
        this._event$ = args.event$ || new rxjs_1.Subject();
        this.event$ = this._event$.pipe((0, operators_1.takeUntil)(this.dispose$), (0, operators_1.map)(function (e) { return _this.toDispatchEvent(e); }), (0, operators_1.share)());
    }
    Store.create = function (args) {
        return new Store(args);
    };
    Store.prototype.dispose = function () {
        this._dispose$.next();
        this._dispose$.complete();
    };
    Object.defineProperty(Store.prototype, "isDisposed", {
        get: function () {
            return this._dispose$.isStopped;
        },
        enumerable: false,
        configurable: true
    });
    Object.defineProperty(Store.prototype, "state", {
        get: function () {
            return tslib_1.__assign({}, this._.state);
        },
        enumerable: false,
        configurable: true
    });
    Store.prototype.dispatch = function (event) {
        this._event$.next(event);
        return this;
    };
    Store.prototype.on = function (type) {
        return this.event$.pipe((0, operators_1.filter)(function (e) { return e.type === type; }), (0, operators_1.map)(function (e) { return e; }));
    };
    Store.prototype.toDispatchEvent = function (event) {
        var _this = this;
        var type = event.type, payload = event.payload;
        var from = this.state;
        var result = {
            type: type,
            payload: payload,
            get state() {
                return tslib_1.__assign({}, from);
            },
            change: function (next) {
                var to = typeof next !== 'function'
                    ? tslib_1.__assign({}, next) : (0, immer_1.default)(from, function (draft) {
                    next(draft);
                    return undefined;
                });
                var isCancelled = false;
                var change = { type: type, event: event, from: from, to: to };
                _this._changing$.next({
                    change: change,
                    isCancelled: isCancelled,
                    cancel: function () { return (isCancelled = true); },
                });
                if (isCancelled) {
                    return result;
                }
                _this._.state = to;
                _this._changed$.next(change);
                return result;
            },
            dispatch: function (event) {
                _this.dispatch(event);
                return result;
            },
        };
        return result;
    };
    return Store;
}());
exports.Store = Store;