Undefined method 'User message path" in Rails 3 project - ruby-on-rails

Question

I am trying to add a link to my Posts>Index page which lets people send direct message (using Simple Private Messaging) to the creator of the Post.
Currently I have a link to /messages/new to do this, but this is not working - Iget the following error in my app when I try to access /messages/new.
I want to replace the link to /messages/new (in POSTS>INDEX file below) with something better that works. Let me know if you have any thoughts!!
**NoMethodError in Messages#new**
Showing /Users/fkhalid2008/loand/app/views/messages/new.html.erb where line #1 raised:
undefined method `user_messages_path' for #<#<Class:0x12a77f198>:0x12a76dce0>
Extracted source (around line #1):
1: <% form_for #message, :url => user_messages_path(#user) do |f| %>
2: <p>
3: To:<br />
4: <%= f.text_field :to %>
ADDITIONAL INFORMATION: The app itself is like Gumtree.com, where Users come and create Posts (e.g. selling my car), and people respond my sending them Messages (through the Simple Pvt Messages plugin).
Thanks!
Faisal
MESSAGES>NEW VIEW
<% form_for #message, :url => user_messages_path(#user) do |f| %>
<p>
To:<br />
<%= f.text_field :to %>
<%= error_message_on #message, :to %>
</p>
<p>
Subject:<br />
<%= f.text_field :subject %>
<%= error_message_on #message, :subject %>
</p>
<p>
Message<br />
<%= f.text_area :body %>
<%= error_message_on #message, :body %>
</p>
<p>
<%= submit_tag "Send" %>
</p>
<% end %>
MESSAGE MODEL
class Message < ActiveRecord::Base
is_private_message
attr_accessor :to
end
ROUTES.RB
Mysalary::Application.routes.draw do
resources :messages do
collection do
post :delete_selected
end
end
resources :users
resources :profiles
resources :pages
resources :posts
get "pages/home"
get "pages/about"
get "pages/legal"
get "pages/feedback"
root :to => 'posts#new'
end
MESSAGES CONTROLLER
class MessagesController < ApplicationController
before_filter :set_user
def index
if params[:mailbox] == "sent"
#messages = #user.sent_messages
else
#messages = #user.received_messages
end
end
def show
#message = Message.read_message(params[:id], current_user)
end
def new
#message = Message.new
if params[:reply_to]
#reply_to = #user.received_messages.find(params[:reply_to])
unless #reply_to.nil?
#message.to = #reply_to.sender.login
#message.subject = "Re: #{#reply_to.subject}"
#message.body = "\n\n*Original message*\n\n #{#reply_to.body}"
end
end
end
def create
#message = Message.new(params[:message])
#message.sender = #user
#message.recipient = User.find_by_login(params[:message][:to])
if #message.save
flash[:notice] = "Message sent"
redirect_to user_messages_path(#user)
else
render :action => :new
end
end
def delete_selected
if request.post?
if params[:delete]
params[:delete].each { |id|
#message = Message.find(:first, :conditions => ["messages.id = ? AND (sender_id = ? OR recipient_id = ?)", id, #user, #user])
#message.mark_deleted(#user) unless #message.nil?
}
flash[:notice] = "Messages deleted"
end
redirect_to :back
end
end
private
def set_user
#user = User.first
end
end
POSTS>INDEX VIEW
<table class="table table-striped">
<tbody>
<% #posts.each do |post| %>
<tr>
<td>I am a <%= post.title %> getting married in <%= post.job %> in <%= post.location %>, and looking for a <%= post.salary %>. My budget is <%= post.salary %>.</td>
<td> <button class="btn" data-toggle="button" onClick="javascript:location.href = '/messages/new';" />Contact</button></td>
<td><%= time_ago_in_words(post.created_at) %> ago.</td>
<!--/.
<td><%= link_to 'Show', post %></td>
<td><%= link_to 'Edit', edit_post_path(post) %></td>
<td><%= link_to 'Destroy', post, :confirm => 'Are you sure?', :method => :delete %></td>
-->
</tr>
<% end %>
</tbody>
</table>

Answer 1

you routes.rb doesn't define path user_messages_path, it's simple :)
If you want nested restful routes, you need something like
resources :users do
resources :messages
end

Answer 2

Just use
<% form_for #message do |f| %>
<% end %>