app.rb

require 'date'

$config = {
    "formats" => {
      "comma" => {
        "date_format" => "%m/%d/%Y", 
        "parts" => {
          "date" => 2, 
          "city" => 1, 
          "name" => 0
        }, 
        "split" => ", ", 
        "cities" => {
          "New York City" => "New York City", 
          "Atlanta" => "Atlanta", 
          "Los Angeles" => "Los Angeles"
        }
      }, 
      "dollar" => {
        "date_format" => "%m-%d-%Y", 
        "parts" => {
          "date"  => 1, 
          "city"  => 0, 
          "last_name" => 2, 
          "name" => 3
        }, 
        "split" => " $ ", 
        "cities" => {
          "NYC" => "New York City", 
          "ATLN" => "Atlanta", 
          "LA" => "Los Angeles"
        }
      }, 
      "date_print" => "%-m/%-d/%Y"
    }
  }

class Entity
    attr_accessor :name, :last_name, :city, :date

    def initialize(params={})
        @name = params[:name]
        @last_name = params[:last_name]
        @city = params[:city]
        @date = params[:date]
    end

    def to_s
        "#{@name} #{@city} #{@date}"
    end
end

class StringParser
    def self.call(params)
        string = params[:string]
        format = params[:format]
        
        format_hash = $config['formats'][format]

        parts = string.split(format_hash['split'])

        name = parts[format_hash['parts']['name']]
        last_name = format_hash['parts']['last_name'] ? parts[format_hash['parts']['last_name']] : nil
        city = format_hash['cities'][parts[format_hash['parts']['city']]]

        date = Date.strptime(parts[format_hash['parts']['date']], format_hash['date_format']).strftime($config['formats']['date_print'])  

        Entity.new(name: name, city: city, date: date, last_name: last_name)
    end
end

class App
    def self.run(params)

        comma = params[:comma].map{|c| StringParser.call(string: c, format: 'comma') }
        dollar = params[:dollar].map{|d| StringParser.call(string: d, format: 'dollar') }

        comma.concat(dollar).sort_by{|x| x.city}.each{|c| puts c}
    end
end

COMMA_ENTRIES = [ # First name, City, Birth date
  'Mckayla, Atlanta, 5/29/1986',
  'Elliot, New York City, 4/3/1947',
]
DOLLAR_ENTRIES = [ # City, Birth date, Last name, First name
  'LA $ 10-4-1974 $ Nolan $ Rhiannon',
  'NYC $ 12-1-1962 $ Bruen $ Rigoberto',
]

App.run(comma: COMMA_ENTRIES, dollar: DOLLAR_ENTRIES)

# WRITE YOUR SPECS HERE
puts "\n\n\n"
puts "Test model correct to_s"
entity = Entity.new(name: 'Rhiannon', last_name: 'Nolan', city: 'New York City', date: '04/03/1947')
puts "Assert equal #{'Rhiannon New York City 04/03/1947' == entity.to_s}"
puts "************************************************"

puts "Test string parser with dollar"
entity = StringParser.call(string: 'LA $ 10-4-1974 $ Nolan $ Rhiannon', format: 'dollar')
puts "Instance of Entity? #{entity.instance_of?(Entity)}"
puts "Assert equal #{'Rhiannon Los Angeles 10/4/1974' == entity.to_s}"
puts "************************************************"

puts "Test string parser with comma"
entity = StringParser.call(string: 'Elliot, New York City, 4/3/1947', format: 'comma')
puts "Instance of Entity? #{entity.instance_of?(Entity)}"
puts "Assert equal #{'Elliot New York City 4/3/1947' == entity.to_s}"
puts "************************************************"