todo.csv

Move with Lil to the black mountain hills of Dakota
Lose Lil to Danny
Get hit in the eye by Danny
Walk into town seeking revenge
Book room at local saloon
Check into room and read Gideon's bible
Drink too much gin
Overhear Lil and Danny in neighboring room
Burst into neighboring room and declare a showdown
Get shot by Danny and collapse in corner
Visit doctor
Return to room and read Gideon's bible
Sing along! D'do d'do d'do do do d'do d'do d'do

todo.rb

require 'csv'

# Domain-Specific Model
class Task

  attr_reader :statement, :id
  attr_accessor :complete

  def initialize(id, statement, complete = 'false')
    @id = id
    @statement = statement
    @complete = complete
  end

  def to_s
    @complete == 'true' ? check = "X" : check = " "
    "#{@id}.".ljust(4) + "[#{check}] #{@statement}"
  end
end

# Model
class List

  attr_reader :tasks
  def initialize
    @tasks = []
  end

  def add(string, complete = 'false')
    task = Task.new(@tasks.length+1, string, complete)
    @tasks << task
  end

  def parse(filename)
    CSV.foreach(filename) { |csv| add(csv[0], csv[1]) }
  end

  def delete_by_id(id_number)
    @tasks.delete_if { |task| task.id == id_number }
  end

  def complete_by_id(id_number)
    @tasks.each { |task| task.complete = 'true' if task.id == id_number }
  end

  def print_to_csv(filename)
    CSV.open(filename, 'wb') do |csv| 
      @tasks.each { |task| csv << [task.statement, task.complete] }
    end
  end
end

# View
class View
  def self.get_selection(list)
    case ARGV[0]
    when 'add'
      string = ARGV[1..-1].join(' ')
      list.add(string)
    when 'list'
      self.print_tasks(list)
    when 'delete'
      list.delete_by_id(ARGV[1].to_i)
    when 'complete'
      list.complete_by_id(ARGV[1].to_i)
    else
      puts 'NOT VALID'
    end
  end

  def self.print_tasks(list)
    list.tasks.each { |task| puts task }
  end

  def self.print_to_file(list, filename)
    File.open(filename, 'w') do |file|
      list.tasks.each { |task| file.puts task }
    end
  end

end

#DRIVER CODE

#Controller
class Todo
  def self.start(csv_file, text_file)
    list = List.new
    list.parse(csv_file)
    View.get_selection(list)
    list.print_to_csv(csv_file)
    View.print_to_file(list, text_file)
  end
end

Todo.start('todo.csv', 'todo.txt')