rails app
cd app

script/generate nifty_authentication
script/generate nifty_layout
script/generate model status user_id:integer message:string created_at:datetime
script/generate model friendship user_id:integer friend_id:integer
script/generate controller statuses
rm public/index.html
rake db:migrate

belongs_to :user
validates_presence_of :user_id, :message, :created_at

belongs_to :user
belongs_to :friend, :class_name => 'User'
validates_uniqueness_of :friend_id, :scope => :user_id
validates_presence_of :user_id, :friend_id

has_many :statuses, :dependent => :destroy
has_many :friendships
has_many :friends, :through => :friendships

def add_friend(friend)
  friendship = friendships.build(:friend_id => friend.id)
  friendship.save!
end

def remove_friend(friend)
  friendship = Friendship.find(:first, :conditions => ["user_id = ? and friend_id = ?", self.id, friend.id])
  if friendship
    friendship.destroy
  end  
end

def all_statuses
  Status.find(:all, :conditions => ["user_id in (?)", friends.map(&:id).push(self.id)], :order => "created_at desc")
end

def is_friend?(friend)
  return self.friends.include? friend
end

def friends_of
  Friendship.find(:all, :conditions => ["friend_id = ?", self.id]).map{|f|f.user}
end

validates_exclusion_of :username, :in => %w(following), :message => "Sorry, cannot use this username"

before_filter :login_required

def index
  @statuses = current_user.all_statuses
end

def show
  @user = User.find_by_username(params[:username])
  @statuses = @user.all_statuses
end

def toggle_follow
  @user = User.find_by_username(params[:username])
  if current_user.is_friend? @user
    current_user.remove_friend(@user)
    flash[:notice] = "You are no longer following #{@user.username}"
  else
    current_user.add_friend(@user)
    flash[:notice] = "You are now following #{@user.username}"
  end
  redirect_to user_statuses_path(@user.username)
end

def create
  status = current_user.statuses.build(params[:status])
  status.message = status.message[0..140]
  status.created_at = Time.now
  status.save!
  redirect_to root_path
end

map.root :controller => "statuses"
map.resources :statuses
map.toggle_follow '/:username/toggle_follow', :controller => 'statuses', :action => 'toggle_follow'
map.user_statuses '/:username', :controller => 'statuses', :action => 'show'

<% if current_user %>
  <div style="float: right;">
      Logged in as <%= current_user.username %> | <%= link_to "Logout", logout_path %>
  </div><br />
<% end %>

<h1>Welcome <%= current_user.username %></h1>
<% form_for Status.new do |f| %>
  <%= f.text_area :message %>
  <%= f.submit "Post" %>
<% end %>

<ul>
  <% @statuses.each do |status| %>
  <li><%= link_to status.user.username, user_statuses_path(status.user.username) %> - <%= h status.message %> - <%= distance_of_time_in_words_to_now(status.created_at) %> ago</li>
  <% end %>
</ul>

<%= pluralize(current_user.statuses.length, "post") %>
<%= current_user.friends.count %> following
<%= pluralize(current_user.friends_of.length, "follower") %>

<h1><%= @user.username %></h1>

<%- form_tag toggle_follow_path do -%>
  <% if current_user.is_friend? @user %>
    <%= submit_tag "Following"%>
  <% else %>
    <%= submit_tag "Not Following"%>
  <% end %>
<%- end -%>  

<ul>
  <% @statuses.each do |status| %>
  <li><%= h status.message %> - <%= distance_of_time_in_words_to_now(status.created_at) %> ago</li>
  <% end %>
</ul>