// code
const add2 = a => b => a + b;

const inc = add2(1);

const compose2 = (f, g) => x => f(g(x));

const compose = (...fns) => x => fns.reduceRight((acc, fn) => fn(acc), x);

const trace = label => value => {
    console.log(`${label}::${value}`);
    return value;
};


module.exports = {
    add2,
    inc,
    compose2,
    compose,
    trace,
};


// tests
const test = require('tape');
const { add2, inc, compose2, compose, trace, words, reverse, unwords, reverseLine } = require('./index');

test('add2:: Number -> Number -> Number', assert => {
    const msg = 'add2 should take two numbers and must return the sum';
    const actual = add2(1)(2);
    const expected = 3;

    assert.same(actual, expected, msg);
    assert.end();
});

test('inc:: Number -> Number', assert => {
    const msg = 'inc should increase a value';
    const actual = inc(1);
    const expected = 2;

    assert.same(actual, expected, msg);
    assert.end();
});

test('compose2:: (f, g) -> a -> b', assert => {
    const double = x => x * 2;
    const msg = 'should execute f after g';
    const doubleInc = compose2(double, inc);
    const actual = doubleInc(20);
    const expected = 42;

    assert.same(actual, expected, msg);
    assert.end();
});

test('compose:: (...Function) -> a -> b', assert => {
    const double = x => x * 2;
    const msg = 'should compose all functions';
    const doubleInc = compose(double, inc);
    const actual = doubleInc(20);
    const expected = 42;

    assert.same(actual, expected, msg);
    assert.end();
});

test('trace:: String -> a -> a', assert => {
    const msg = 'should print a value as `label::value`';
    const actual = trace('test')('myValue');
    const expected = 'myValue';

    assert.same(actual, expected, msg);
    assert.end();
});

const double = x => x * 2;
const doubleInc = compose(
    trace('after double'),
    double,
    trace('after inc'),
    inc
);

const person = {
    lastname: "Fernandez",
};

const createUser = (name) => {
    let prefix = "Name::";
    return Object.assign(Object.create(person), { name }, {
        getName: () => `${prefix}${name}`,
    });
};

console.log(createUser('Miriam').getName());

doubleInc(20);