Don't added a link to next/previous page ( string 35

app.rb

#!/usr/bin/env ruby
require 'rubygems'
require 'sinatra'

# TODO: rewrite it to class
form = <<TEXT
<form action="/post" method="POST">
Name: <input name="name" value="" size="10"><br> 
Message: <input name="msg" value="" size="140"><br>
<center><input type="submit"></center>
</form>
<br\>
<a href=\"/stream/\">Look a stream!</a>
TEXT
form.freeze
$home = "<a href=\"/\">Go to home!</a>"
$home.freeze
# General array of messages
$msgs = Array.new

# class Stream
# 	def each
# #		$msgs.each_with_index { |item, index| yield "#{item[0]}<br/>#{item[1]}<br/>#{item[2]}<br/>---------------------------<br\>"}
# 		"<a href='/stream/1'>Go to first stream page!</a>"
# 	end
# end

def page_messages(n)
	n = n.to_i
	s = String.new
	if n.integer? and n>0 and $msgs.length >= (n-1) * 10
		$msgs.reverse[(n*10)-10...n*10].each_with_index do |item, index|
			s << "#{$msgs.length - index} # Name: #{item[0]}<br/>Time: #{item[1]}<br>Message: #{item[2]}<br/><br/>"
		end
		# added link to next/previous page
		if (n != 1)
			s << "<a href='/stream/#{n-1}'>\<\<Back |</a>"
		end
		if (($msgs.length/10)+1 > n)
			s << "<a href='/stream/#{n+1}'>Next\>\></a>"
		end
		s << $home << "<br/>"
	else
		s = "Page not found!#{$home}"
	end
	s
end

get '/' do
#  draw a form to input message
	form
end

post '/post' do
  # check information, sended in form, to valid
	time = Time.now
	unless params[:name].empty? and params[:msg].empty?
	  if params[:msg].length <= 140 and params[:name]. length <= 10
	    # if every right, added in array messages
	    $msgs << [params[:name], time,params[:msg]]
	    "Send success!#{$home}"
	  else
	    "Error! Big message or name: #{params[:name]} say \"#{params[:msg]}\"<br/>#{$home}}"
	  end
	else
	  "Empty!#{$home}"
	end
end

get '/stream/:page' do
	page_messages(params[:page])
end

# Browse message in array.
get('/stream/') { "<a href='/stream/1'>Go to first stream page!</a>" }