import Core from "../lib/core";

const Patterns = Core.Patterns;

const SpecialForms = Core.SpecialForms;

const Tuple = Core.Tuple;

import Enum from "../lib/enum";

import chai from 'chai';

var expect = chai.expect;

const $ = Patterns.variable();

function map_fetch(map, key){

if(key in map){

return new Tuple(Symbol.for('ok'), map[key]);

}

return Symbol.for('error');

}

describe('with', () => {

it('normal', () => {

/*

opts = %{width: 10, height: 15}

with {:ok, width} <- Map.fetch(opts, :width),

{:ok, height} <- Map.fetch(opts, :height),

do: {:ok, width * height}

{:ok, 150}

*/

let opts = { width: 10, height: 15 };

let value = SpecialForms._with(

[new Tuple(Symbol.for('ok'), $), () => map_fetch(opts, "width")],

[new Tuple(Symbol.for('ok'), $), (width) => map_fetch(opts, "height")],

(width, height) => new Tuple(Symbol.for('ok'), width * height)

);

expect(value).to.eql(new Tuple(Symbol.for('ok'), 150));

});

it('without match', () => {

/*

opts = %{width: 10}

with {:ok, width} <- Map.fetch(opts, :width),

{:ok, height} <- Map.fetch(opts, :height),

do: {:ok, width * height}

:error

*/

let opts = { width: 10 };

let value = SpecialForms._with(

[new Tuple(Symbol.for('ok'), $), () => map_fetch(opts, "width")],

[new Tuple(Symbol.for('ok'), $), (width) => map_fetch(opts, "height")],

(width, height) => new Tuple(Symbol.for('ok'), width * height)

);

expect(value).to.eql(Symbol.for('error'));

});

it('bare expression', () => {

/*

opts = %{width: 10}

with {:ok, width} <- Map.fetch(opts, :width),

double_width = width * 2,

{:ok, height} <- Map.fetch(opts, :height),

do: {:ok, double_width * height}

{:ok, 300}

*/

let opts = { width: 10, height: 15 };

let value = SpecialForms._with(

[new Tuple(Symbol.for('ok'), $), () => map_fetch(opts, "width")],

[$, (width) => width * 2],

[new Tuple(Symbol.for('ok'), $), (width, double_width) => map_fetch(opts, "height")],

(width, double_width, height) => new Tuple(Symbol.for('ok'), double_width * height)

);

expect(value).to.eql(new Tuple(Symbol.for('ok'), 300));

});

});