'use strict';

const Task = require('./task');

class MemTaskService {

    constructor() {
        this.tasks = [
            Task.withId('1', 'Task 1'),
            Task.withId('2', 'Task 2')
        ];
    }

    clone(what) {
        return JSON.parse(JSON.stringify(what));
    }

    getTasks() {
        return Promise.resolve(this.clone(this.tasks));
    }

    getTask(id) {
        let found = this.clone(this.tasks)
            .filter(each => each._id === id)
            .pop();

        return found ? Promise.resolve(found) : Promise.reject('no task with id: ' + id);
    }

    saveTask(task) {
        if (!task._id) {
            task._id = this.getId();
            this.tasks.push(task);
            return Promise.resolve();
        }

        this.tasks = this.tasks
            .map(each =>each._id === task._id ? task : each);

        return Promise.resolve();
    }

    deleteTask(id) {
        this.tasks = this.tasks
            .filter(each => each._id !== id);

        return Promise.resolve();
    }

    getId() {
        return (Math.random() + 'A').substr(2);
    }

}

module.exports = MemTaskService;