# ActsAsChattable
# ===============
#
# ActsAsChattable is a plugin with make web chatting easy.
# 
# With this plugin, you can add a user-to-user chatting system into your Rails app 
# within 3-minutes.
#
# It uses some codes from Chatten project (http://rubyforge.org/projects/chatten/),
# So let's give our thanks to the author of Chatten: Jacob Pedersen.
#
# Version:	0.1.0 - beta						     
# Author: Yuanyi Zhang -- http://elctech.com
# Contributors:	
# License:	Ruby MIT						     
#
# ==Installation
#
# ./script/plugin install https://svn.elctech.com/svn/public/plugins/acts_as_chattable
#
# ==Demo
#
# svn co https://svn.elctech.com/svn/public/demo/acts_as_chattable
#
# ==Usage
#
# * At first, I assume you have a model named User and a controller named UsersController, 
#   I also assume you have a helper named 'current_user' which will return the current
#   user (it should be there if you use restful_auth). If you don't have these yet, 
#   create them and let's go!
#
# * create chat_message model and migration:
#
#   script/generate chattable
#
# * add acts_as_chattable to user model
#
#   class User
#     acts_as_chattable
#     ...
#
#     def name
#       ...
#     end
#   end
#
#   You'd better to define name method for User, or all users' name will be displayed as 'Unknown'.
#
# * include chat system in users controller
#
#   class UsersController
#     include ChatSystem
#     ...
#   end
#
# * render chat in views
#
#   <%= render_chat(friends, use_yui) %>
#   <%= buddy_list(friends, use_yui) %>
#
#   friends should be an array of user with presents current user's friends. 
#   use_yui indicate if YUI should be used to get a better look, default is true.
#
#   You can get more info about these two helpers with rdoc.
#
# * It's done, open your browser and start to enjoy the chatting.
#
# ===================================
# For more detailed examples with sample images visit http://elctech.com/blog
# All Feedbacks/Comments/Issues are welcome.

module ActsAsChattable # :nodoc
  module ViewHelpers # :nodoc
    # This helper will render chat views for specific page.
    # 
    # friends is an array of user which should presents current user's friends. <br />
    # use_yui indicate if YUI should be used to get a better look, default is true.
    #
    # *Examples*
    #
    # # users_controller.rb
    # def index
    #   @friends = current_user.friends
    # end
    #
    # # index.html.erb
    # <%= render_chat @friends %>
    #
    def render_chat(user, friends)
      chat = <<-JS
        <script language='Javascript'>
          var top_win = 100;
          var left_win = 100;
        </script>
      JS
      
      chat += <<-JS
      <div id="flashcontent" style="width:0; height:0;"></div><script type="text/javascript">
      //<![CDATA[
      Juggernaut.listenToChannels({ 
                                      host: 'localhost', 
                                      num_tries: 3, 
                                      num_secs: 3, 
                                      unique_id: 'null', 
                                      swf_address: '/juggernaut.swf', 
                                      flash_version: '8',
                                      width: '1',
                                      height: '1',
                                      base64: false, 
                                      port: 443, 
                                      channels: ["#{user.id}"]});
      //]]>
      </script>
      JS

      chat += <<-CSS
      <style>
      .chat-window
      {
      	border: 1px solid #777;
      	width: 280px;
      	overflow: auto;
      	position: absolute;
      	background: #fff;
      	z-index: 15;
      }

      .chat-handle
      {
      	background: #28e;
      	color: #fff;
      	text-align: center;
      	cursor: move;
      }

      .chat-handle .close
      {
      	top: 2px;
      	right: 5px;
      	width: 12px;
      	height: 12px;
      	background-image:url(/images/chattable/close.gif);
      	position: absolute;
      	cursor: pointer;
      }

      .messages
      {
      	margin: 5px 10px;
      	border-bottom: 1px solid #777;
      	padding: 3px;
      	height: 100px;
      	width: 250px;
      	overflow: auto;
      	clear: left;
      }

      .messages p {margin: 0; padding: 0;}
      .messages strong {margin: 0;}

      .send_message
      {
      	margin: 5px 10px;
      	padding: 0;
      }

      .send_message form
      {
      	display: inline;
      	margin: 0;
      	padding: 0;
      }

      .send_message input[type="text"]
      {
      	margin-right: 10px;
      	width: 190px;
      }

      .send_message input[type="submit"]
      {
      	padding:3px;
      	border: 1px solid #777; 
      	font: normal 1em Verdana, sans-serif;
      	color:#777;
      }

      #users p.name
      {
      	font-weight: bold;
      }
      </style>
      CSS

      friends.each do |friend|
        chat += "<div id='chat#{friend.id}' class='chat-window'>"
        chat += <<-HANDLE
          <div id='chat_header#{friend.id}' class='chat-handle'>
            Chat with #{friend.name}:

            <div class='close' onclick="document.getElementById('chat#{friend.id}').style.display = 'none'">
            </div>
          </div>
        HANDLE
        chat += <<-CHATWINDOW
      	  <div id="messages#{friend.id}" class="messages">
        	</div>

      		<div id="send_message#{friend.id}" class="send_message">
      	CHATWINDOW

      	  chat += form_remote_tag(:url => { :controller => 'chat', :action => :send_data, :from => user.id, :to => friend.id },
                                    :complete => "$('chat_input#{friend.id}').value = ''" )
        	  chat += text_field_tag "chat_input#{friend.id}"
        	  chat += submit_tag 'Send', :id => 'commit'
       	  chat += '</form>'
        chat += "</div></div>"

        chat += <<-JS
          <script language='JavaScript'>
            $('chat#{friend.id}').style.display = 'none';
            new Effect.Move('chat#{friend.id}', {x:top_win, y:left_win});
            top_win += 50;
            left_win += 50;
            new Draggable('chat#{friend.id}', {handle:'chat_header#{friend.id}'});
          </script>
        JS
      end
      chat
    end
    
    # This helper will generate a buddy list for you, when user click
    # the friend's name in buddy list, a chatting window will be open to allow
    # user chatting with this friend.
    #
    # *Example*
    #
    # <%= buddy_list(current_user.friends) %>
    #
    # If you want to customize the buddy list, use chat_link which will
    # provide a link to open the chatting window.
    #
    def buddy_list(friends)
      chat = '<ul class="friend_list">'
      
      friends.each do |friend|
        chat += '<li>' + link_to(friend.name, '#', :onclick => chat_link(friend)) + '</li>'
      end
      
      chat + '</ul>'
    end
    
    # Link which will open a chatting window to chat with this user.
    # 
    # if you didn't use yui to render the chatting window, then
    # use_yui should be set to false to show a non-yui chatting
    # window.
    #
    # *Example*
    #
    # To generate a buddy list:
    #
    # <% user.firends.each do |friend| %>
    #   <%= link_to friend.name, friend.chat_link %>
    # <% end %>
    #
    # It's equal to buddy_list helper.
    #
    def chat_link(friend)
      "$('chat#{friend.id}').show(); $('chat_input#{friend.id}').focus()"
    end
  end
end