MVC Intro - TODO App

app.rb

require_relative "task"
require_relative "task_repository"
require_relative "tasks_controller"
require_relative "router"

require "byebug"


# Create an instance of TaskRepository
task_repository = TaskRepository.new

# task = Task.new("Learn MVC")

# task_repository.add_task(task)
# p task_repository.all


# Create a controller instance
# Needs a TaskRepository instance
tasks_controller = TasksController.new(task_repository)

# Create the Router instance
# Needs a TasksController instance
router = Router.new(tasks_controller)

# Start the programme
router.run


# Temporary FOR DEBUGGING
# Create an instance of TaskRepository
# task_repository = TaskRepository.new

# # Create an instance of Task
task = Task.new("Learn MVC")

task_repository.add_task(task)
# p task_repository.all

router.rb

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

  # Public Interface
  def run
    @running = true
    while @running do
      # Display the menu
      print_actions
      # Capture user action
      action = gets.chomp.to_i
      # Dispatch the action to the controller
      dispatch(action)
    end
  end

  private

  def print_actions
    puts "\n----- MENU -----"
    puts "1. List Tasks"
    puts "2. Add Task"
    puts "3. Mark a Task as Done"
    puts "4. Remove a Task"
    puts "5. Quit"
    puts "\n----------------"
  end

  def dispatch(action)
    case action
    when 1 then @controller.list
    when 2 then @controller.add
    when 3 then @controller.mark_as_done
    when 4 then @controller.destroy
    when 5 then @running = false
    end
  end
end

task.rb

# This is out model

class Task
  attr_reader :description

  # Task.new("Learn OOP")
  def initialize(description)
    # @description = "Learn OOP"
    @description = description
    @done = false # Boolean
  end

  # Read for booleans - by convention ends with ?
  def done?
    @done
  end

  # attr_reader implements this method for us
  # def description
  #   @description
  # end

  def mark_as_done!
    @done = true
  end

  def to_s
    done = done? ? "[x]" : "[ ]"
    "#{done} #{@description}"
  end
end

task_repository.rb

# Repo (Will later be replaced by a real DB)
class TaskRepository
  def initialize
    @tasks = []
  end

  def all
    @tasks
  end

  # Receives a task instance
  def add_task(task)
    @tasks << task
  end

  def find(index)
    # Array CRUD: Read
    @tasks[index]
  end

  def remove(index)
    # Array CRUD: Delete
    @tasks.delete_at(index)
  end
end

tasks_controller.rb

require_relative "tasks_view"

class TasksController
  def initialize(task_repository)
    @task_repository = task_repository
    @view = TasksView.new
  end

  def list
    display_tasks
  end

  def add
    # Tell the view to ask the user for a task desc.
    # Store the user description
    description = @view.ask_for_description
    # Create a Task instance
    task = Task.new(description)
    # Tell the repo to add the new task
    @task_repository.add_task(task)
  end

  def mark_as_done
    display_tasks
    # Tell the view to ask the User for an index
    index = @view.ask_for_index
    # Ask the repo to find the task with the index
    task = @task_repository.find(index)
    # Ask the task to mark itself as done
    task.mark_as_done!
  end

  def destroy
    # Display the tasks
    display_tasks
    # Tell the view to ask the User for an index
    index = @view.ask_for_index
    # Asks the repo to remove the task with the index
    @task_repository.remove(index)
  end

  private

  def display_tasks
    # Ask the repo for the list of tasks
    tasks = @task_repository.all
    # Tell the view to display the tasks
    @view.display_tasks(tasks)
  end
end

tasks_view.rb

# Only has behaviour
# User by the TasksController
class TasksView
  def display_tasks(tasks)
    # 1 - [] Learn MVC
    # 2 -
    tasks.each_with_index do |task, index|
      puts "#{index + 1} - #{task}"
    end
  end

  def ask_for_description
    puts "What's the task you want to add?"
    print "> "
    # Capture and return User input
    gets.chomp
  end

  def ask_for_index
    puts "Which task?"
    print "> "
    # Capture and return User input
    # convert to integer and to the real index
    gets.chomp.to_i - 1
  end
end