app.rb

require_relative "task"
require_relative "repository"
require_relative "view"
require_relative "controller"
require_relative "router"

repository = Repository.new
view = View.new
controller = Controller.new(view, repository)
router = Router.new(controller)

router.run

controller.rb

# Role: Coordinate with the view and repo to fulfill user actions

class Controller
  def initialize(view, repository)
    @view = view # instance of View
    @repository = repository # instance of Repository
  end

  # User action: create a new task
  def create_task
    task_name = @view.ask_for_name
    task = Task.new(task_name)
    @repository.add_task(task)
  end

  # User action: display all tasks
  def list
    # repo: give me all the tasks
    tasks = @repository.all

    # view: take these tasks and display them
    @view.display_tasks(tasks)
  end

  # User action: mark a task as done
  def mark_as_done
    # view: ask for specific task index
    task_index = @view.ask_for_task_index

    # repo: get the task belonging to that index
    task = @repository.find(task_index)

    # mark the task as done
    task.mark_as_done!
  end
end

repository.rb

# Role: To store and retrieve tasks

class Repository
  def initialize
    @tasks = [] # An array of Task instances (not Strings or Hashes or etc...)

    # go to csv and load up tasks 
  end

  def add_task(new_task)
    @tasks << new_task

    # save to the csv file
  end

  def all
    return @tasks
  end

  def find(index)
    return @tasks[index]
  end
end

router.rb

# Role: Ask the user what action they'd like to do, and in turn tell the controller

class Router
  def initialize(controller)
    @controller = controller
  end

  def run
    puts "Welcome to TODO!"

    loop do
      puts "What would you like to do?"
      puts "1 - New Task"
      puts "2 - List"
      puts "3 - Mark as done"
      puts "4 - Quit"

      user_input = gets.chomp.to_i

      if user_input == 1
        @controller.create_task
      elsif user_input == 2
        @controller.list
      elsif user_input == 3
        @controller.mark_as_done
      elsif user_input == 4
        break
      else
        puts "Invalid input"
      end
    end
  end
end

task.rb

# Role: Represent each task in our todo/task-manager

class Task
  attr_reader :name, :done

  def initialize(name)
    @name = name
    @done = false
  end

  def mark_as_done!
    @done = true
  end
end

view.rb

# Role: Interact with the user: recieve info (gets) and display info (puts)\

class View
  def ask_for_name
    puts "Enter task name:"
    task_name = gets.chomp
    return task_name
  end

  def display_tasks(tasks)
    tasks.each_with_index do |task, index|
      if task.done
        puts " #{index} - [X] #{task.name}"
      else
        puts " #{index} - [ ] #{task.name}"
      end
    end
  end

  def ask_for_task_index
    puts "Enter task index:"
    task_index = gets.chomp.to_i
    return task_index
  end
end