var fs = require('fs');

var _ = require('lodash');

var DATA = 'data/todos.json';

var PRETTIFY_WS = 4;

function getAll(resolve) {

fs.readFile(DATA, function(err, data) {

resolve(JSON.parse(data));

});

}

function commit(data, resolve) {

fs.writeFile(DATA, JSON.stringify(data, null, PRETTIFY_WS));

}

function add(todo, resolve) {

getAll(function (data) {

data.todos.push(todo);

commit(data);

resolve(data);

});

}

function del(id, resolve) {

getAll(function (data) {

var todos = _.filter(data.todos, function (todo) {

return todo.id != id;

});

data.todos = todos;

commit(data);

resolve(data);

});

}

module.exports = {

getAll: getAll,

commit: commit,

add: add,

del: del

}