HORIZON PROJECT

'use strict';

Object.defineProperty(exports, "__esModule", {

    value: true

});

var _noop = require('lodash/noop');

var _noop2 = _interopRequireDefault(_noop);

var _rest = require('./internal/rest');

var _rest2 = _interopRequireDefault(_rest);

var _reduce = require('./reduce');

var _reduce2 = _interopRequireDefault(_reduce);

function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }

/**

 * Version of the compose function that is more natural to read. Each function

 * consumes the return value of the previous function. It is the equivalent of

 * [compose]{@link module:ControlFlow.compose} with the arguments reversed.

 *

 * Each function is executed with the `this` binding of the composed function.

 *

 * @name seq

 * @static

 * @memberOf module:ControlFlow

 * @method

 * @see [async.compose]{@link module:ControlFlow.compose}

 * @category Control Flow

 * @param {...Function} functions - the asynchronous functions to compose

 * @returns {Function} a function that composes the `functions` in order

 * @example

 *

 * // Requires lodash (or underscore), express3 and dresende's orm2.

 * // Part of an app, that fetches cats of the logged user.

 * // This example uses `seq` function to avoid overnesting and error

 * // handling clutter.

 * app.get('/cats', function(request, response) {

 *     var User = request.models.User;

 *     async.seq(

 *         _.bind(User.get, User),  // 'User.get' has signature (id, callback(err, data))

 *         function(user, fn) {

 *             user.getCats(fn);      // 'getCats' has signature (callback(err, data))

 *         }

 *     )(req.session.user_id, function (err, cats) {

 *         if (err) {

 *             console.error(err);

 *             response.json({ status: 'error', message: err.message });

 *         } else {

 *             response.json({ status: 'ok', message: 'Cats found', data: cats });

 *         }

 *     });

 * });

 */

exports.default = (0, _rest2.default)(function seq(functions) {

    return (0, _rest2.default)(function (args) {

        var that = this;

        var cb = args[args.length - 1];

        if (typeof cb == 'function') {

            args.pop();

        } else {

            cb = _noop2.default;

        }

        (0, _reduce2.default)(functions, args, function (newargs, fn, cb) {

            fn.apply(that, newargs.concat([(0, _rest2.default)(function (err, nextargs) {

                cb(err, nextargs);

            })]));

        }, function (err, results) {

            cb.apply(that, [err].concat(results));

        });

    });

});

module.exports = exports['default'];