to_do.rb

require 'date'

class Task
  def initialize(description)
    @description = description
    @status = "incomplete"
    @priority = 5
    @due_date = Date.today.to_s
  end
  
  def description
    @description
  end  

  def mark_as_complete
    @status = "complete"
  end

  def status
    @status
  end

  def priority
    @priority
  end
  
  def edit_priority(level)
    @priority = level
  end

  def due_date 
    @due_date
  end   

  def edit_due_date(year, month, day)
    @due_date = "#{year}-#{month}-#{day}"
  end  
   
  def complete?
    @status == 'complete'
  end    
end

class List
  def initialize(name)
    @name = name
    @tasks = []
  end

  def name
    @name
  end

  def list_tasks
    @tasks
  end  

  def add_task(task)
    @tasks << task
  end  

  def delete(task)
    @tasks.delete_if {|x| x == task}
  end  

  def sort_by_priority
    @tasks.sort! do |task, next_task|
      task.priority <=> next_task.priority
    end
  end

  def sort_by_due_date
    @tasks.sort! do |task, next_task|
      task.due_date <=> next_task.due_date
    end
  end
end

to_do_program.rb

require './lib/to_do'
require 'date'

@lists = []

def main_menu
  puts "Enter 'cl' to create a new list"
  puts "Enter 'v' to view the names for each of your lists"
  puts "Enter 's' to select a list to edit"
  puts "Enter 'x' to exit"
  main_choice = gets.chomp
  if main_choice == 'cl'
    new_list
  elsif main_choice == 'v'
    display_list_names
    main_menu
  elsif main_choice == 's'
    select_list 
    main_menu
  elsif main_choice == 'x'
    puts "Good-bye!"
  else
    puts "That is not a valid input."
    main_menu
  end
end

def new_list 
  puts "Please enter a name for your list"
  list_name = gets.chomp
  @lists << List.new(list_name)
  puts "New list created."
  main_menu
end

def display_list_names
  @lists.each_with_index do |list, index|
    puts "#{index + 1}. #{list.name}"
  end
end

def select_list
  display_list_names
  puts "Enter the number of the list you would like to edit"
  index_of_list_to_edit = gets.to_i - 1
  @list = @lists[index_of_list_to_edit]
  puts "\n\n#{@list.name} has been selected"
  list_menu
end

def list_menu
  puts "Enter 'a' to add a task or 'l' to list all of your tasks."
  puts "Enter 'c' to mark task as complete"
  puts "Enter 'p' to set priority for the task"
  puts "Enter 'd' to set the due date for the task"
  puts "Press 'x' return to the main menu."
  main_choice = gets.chomp
  if main_choice == 'a'
    add_task
    list_menu
  elsif main_choice == 'l'
    list_tasks
    list_menu
  elsif main_choice == 'x'
    main_menu
  elsif main_choice == 'c'
    complete_task 
    list_menu
  elsif main_choice == 'p'
    task_priority
    list_menu 
  elsif main_choice == 'd'
    task_due_date
    list_menu    
  else
    puts "That is not a valid input."
    list_menu
  end
end

def add_task 
  puts "Enter a description"
  description = gets.chomp
  @list.add_task(Task.new(description)) 
end

def list_tasks
  @list.sort_by_priority
  @list.sort_by_due_date
  @list.list_tasks.each_with_index do |task, index|
    puts "#{index + 1}. #{task.description} - Status: #{task.status} - Priority: #{task.priority} - Due: #{task.due_date}"
  end
  puts "\n\n"
end

def complete_task
  list_tasks
  puts "Please enter the number of the task you wish to set to complete"
  task_choice_index = gets.to_i - 1
  tasks = @list.list_tasks
  if task_choice_index < 0 || task_choice_index > tasks.length
    puts "That is not a task number."
  else
    selected_task = tasks[task_choice_index]
    selected_task.mark_as_complete
    puts "#{selected_task.description} has been marked complete \n\n"
  end
end 

def task_priority
  list_tasks
  puts "Please enter the number of the task you wish set priority"
  task_choice = gets.to_i - 1
  tasks = @list.list_tasks
  if task_choice < 0 || task_choice > tasks.length
    puts "That is not a task number."
  else
    selected_task = tasks[task_choice]
    puts "#{selected_task.description} has been selected"
    puts "Please enter the priority level from 1-5 (5 being the lowest)"
    priority = gets.to_i
    selected_task.edit_priority(priority)
    puts "#{selected_task.description} priority has been set at #{priority} \n\n"
  end
end  

def task_due_date
  list_tasks
  puts "Please enter the number of the task you wish set the due date"
  task_choice = gets.to_i - 1
  tasks = @list.list_tasks
  if task_choice < 0 || task_choice > tasks.length
    puts "That is not a task number."
  else
    selected_task  = tasks[task_choice]
    puts "Please enter the year"
    year = gets.to_i
    puts "Please enter the month"
    month = gets.to_i
    puts "Please enter the day"
    day = gets.to_i
    selected_task.edit_due_date(year, month, day)
    puts "Task due date set to #{selected_task.due_date}\n\n"
  end  
end


main_menu

to_do_spec.rb

require 'rspec'
require 'to_do'
require 'date'

describe Task do 
  it 'is initialized with a description' do 
    test_task = Task.new('walk the dog')
    test_task.should be_an_instance_of Task
  end

  it 'lets you read the description out' do
    test_task = Task.new('walk the dog')
    test_task.description.should eq 'walk the dog'
  end
  
  it 'lets you mark a task as complete' do
    test_task = Task.new('walk the dog')
    test_task.mark_as_complete # complete!
    test_task.status.should eq 'complete'
  end

  describe 'complete?' do 
    it "returns true if the task is completed" do 
      test_task = Task.new("walk the dog")
      test_task.mark_as_complete
      test_task.complete?.should eq true
    end 
  end

  describe 'priority' do
    it 'lets you read the task current priority level' do
      test_task = Task.new("walk the dog")
      test_task.priority.should eq 5
    end
  end

  describe 'edit_priority' do 
    it 'sets the priority number for task' do
      test_task = Task.new("walk the dog")
      test_task.edit_priority(1)
      test_task.priority.should eq 1
    end
  end

  describe 'due_date' do
    it 'lets you read the due date for the task' do
      test_task = Task.new("Walk the dog")
      test_task.due_date.should eq Date.today.to_s
    end

    it 'lets you change the due date for the task' do
      test_task = Task.new("Walk the dog")
      test_task.edit_due_date(2013, 10, 4)
      test_task.due_date.should eq "2013-10-4"
    end  
  end

end

describe List do 
  it 'is intialized with a name' do 
    test_list = List.new("list1")
    test_list.should be_an_instance_of List
  end

  it "lets you read the list of tasks" do 
    test_list = List.new("list")
    test_list.list_tasks.should eq [] # tasks
  end

  it 'add a task to the list' do
    test_list = List.new("List1")
    task = Task.new("Walk the dog")
    test_list.add_task(task)
    list = test_list.list_tasks.should eq [task]
  end  

  it "lets you sort by priority level" do 
    list = List.new("list")
    task = Task.new("Walk the dog")
    task2 = Task.new("Wash the car")
    task2.edit_priority(1)
    list.add_task(task)
    list.add_task(task2)
    list.sort_by_priority
    list.list_tasks.should eq [task2, task]
  end

  it "lets you sort by due date" do 
    list = List.new("list")
    task = Task.new("Walk the dog")
    task2 = Task.new("Wash the car")
    task.edit_due_date(2013, 11, 04)
    list.add_task(task)
    list.add_task(task2)
    list.sort_by_due_date
    list.list_tasks.should eq [task2, task]
  end

  it 'lets you delete a task' do 
    list = List.new("List")
    task = Task.new("walk the dog")
    list.add_task(task)
    list.delete(task)
    list.list_tasks.should eq []
  end

end