"use strict";
var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
    return new (P || (P = Promise))(function (resolve, reject) {
        function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
        function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
        function step(result) { result.done ? resolve(result.value) : new P(function (resolve) { resolve(result.value); }).then(fulfilled, rejected); }
        step((generator = generator.apply(thisArg, _arguments || [])).next());
    });
};
var __asyncValues = (this && this.__asyncValues) || function (o) {
    if (!Symbol.asyncIterator) throw new TypeError("Symbol.asyncIterator is not defined.");
    var m = o[Symbol.asyncIterator], i;
    return m ? m.call(o) : (o = typeof __values === "function" ? __values(o) : o[Symbol.iterator](), i = {}, verb("next"), verb("throw"), verb("return"), i[Symbol.asyncIterator] = function () { return this; }, i);
    function verb(n) { i[n] = o[n] && function (v) { return new Promise(function (resolve, reject) { v = o[n](v), settle(resolve, reject, v.done, v.value); }); }; }
    function settle(resolve, reject, d, v) { Promise.resolve(v).then(function(v) { resolve({ value: v, done: d }); }, reject); }
};
Object.defineProperty(exports, "__esModule", { value: true });
const _scheduler_1 = require("./_scheduler");
const _util_1 = require("./_util");
const observable_1 = require("./observable");
const unsubscribe_1 = require("./unsubscribe");
/**
 * Maps the values emitted by another observable. In contrast to `map()`
 * the `mapper` function returns an array of values that will be emitted
 * separately.
 * Use `flatMap()` to map input values to zero, one or multiple output
 * values. To be applied to an input observable using `pipe()`.
 */
function flatMap(mapper) {
    return (observable) => {
        return new observable_1.default(observer => {
            const scheduler = new _scheduler_1.AsyncSerialScheduler(observer);
            const subscription = observable.subscribe({
                complete() {
                    scheduler.complete();
                },
                error(error) {
                    scheduler.error(error);
                },
                next(input) {
                    scheduler.schedule((next) => __awaiter(this, void 0, void 0, function* () {
                        var e_1, _a;
                        const mapped = yield mapper(input);
                        if (_util_1.isIterator(mapped) || _util_1.isAsyncIterator(mapped)) {
                            try {
                                for (var mapped_1 = __asyncValues(mapped), mapped_1_1; mapped_1_1 = yield mapped_1.next(), !mapped_1_1.done;) {
                                    const element = mapped_1_1.value;
                                    next(element);
                                }
                            }
                            catch (e_1_1) { e_1 = { error: e_1_1 }; }
                            finally {
                                try {
                                    if (mapped_1_1 && !mapped_1_1.done && (_a = mapped_1.return)) yield _a.call(mapped_1);
                                }
                                finally { if (e_1) throw e_1.error; }
                            }
                        }
                        else {
                            mapped.map(output => next(output));
                        }
                    }));
                }
            });
            return () => unsubscribe_1.default(subscription);
        });
    };
}
exports.default = flatMap;
