namespace :remix do
  # Returns true if the indicated server has any file uploads going
  def file_upload_in_progress?(server)
    uploads = `ssh #{server} 'ls -ltr /tmp'`.grep(/mongrel/)
    uploads.each do |upload|
      # See if timestamp is recent
      if upload =~ /([A-Za-z]+ \d\d \d+:\d+)/
	time = Time.parse($1)
        if time > (Time.now - 3.minutes)
	  puts "Current upload: #{upload}"
	  return true
	else
	  puts "Old upload: #{upload}"
        end
      end
    end
    false
  end

  # Updates subversion on the indicated server, and returns an array of
  # conflicts if there were any, or else an empty array.
  def svn_up(server, dir_list = "")
    result = `ssh #{server} 'cd /home/rails/svn/myapp; svn up #{dir_list}'`.split("\n")
    conflicts = result.grep(/^C/)
    return result, conflicts
  end

  def run_sudo(cmd, password)
    puts "Trying sudo password: #{password}"
    IO.popen("sudo -S #{cmd}", "r+") do |io|
      io.puts(password)
      puts io.readlines
    end
  end

  def remote_sudo(server, cmd, password)
    puts "[sudo, #{server}] #{cmd}"
    result = ""
    IO.popen("ssh -T #{server}", "r+") do |io|
      io.puts("sudo -S #{cmd}")
      io.puts(password)
      io.puts("sudo -k")
      io.close_write
      result = io.readlines
    end
    result
  end

  def prompt(msg)
    print msg
    STDIN.readline
  end

  def prompt_password
    prompt("Enter sudo password: ")
  end

  def restart_web(server, password)
    puts remote_sudo(server, "apachectl stop", password)
    puts "[ssh] restart mongrel cluster"
    result = `ssh #{server} 'cd /home/rails/svn/myapp; mongrel_rails cluster::restart --clean; rm -f /tmp/*'`.split("\n")
    puts result.join("\n")
    puts remote_sudo(server, "apachectl start", password)
  end

  def update_and_restart_web(server, password)
    puts "[1 - #{server}] Check for uploads in progress"
    if file_upload_in_progress?(server)
      puts "active upload - can't update"
    else
      puts "[2 - #{server}] Update subversion"
      result, conflicts = svn_up(server)
      if conflicts.size > 0
        puts "ERROR!! File conflicts:"
	puts conflicts.join("\n")
      else
	puts result.join("\n")
        puts "[3 - #{server}] Restart mongrels and apache"
	restart_web(server, password)
      end
    end
  end

  desc "Update svn and restart web1"
  task :update_web1 do
    update_and_restart_web("web1", prompt_password())
  end

  desc "Update svn and restart web2"
  task(:update_web2 => :environment) do
    update_and_restart_web("web2", prompt_password())
  end

  desc "Update svn and restart web3"
  task(:update_web3 => :environment) do
    update_and_restart_web("web3", prompt_password())
  end

  desc "Check that all webs can be updated"
  task(:check_web_update => :environment) do
    puts "[web1] Check for uploads in progress"
    if file_upload_in_progress?("web1")
      puts "WEB1 has uploads!"
    end
    puts "[web2] Check for uploads in progress"
    if file_upload_in_progress?("web2")
      puts "WEB2 has uploads!"
    end
    puts "[web3] Check for uploads in progress"
    if file_upload_in_progress?("web3")
      puts "WEB3 has uploads!"
    end
  end

  desc "Subversion update and restart all webs"
  task(:update_all_webs => [:environment,:check_web_update]) do
    puts "paused. Hit enter to continue..."
    STDIN.readline
    
    password = prompt_password
    update_and_restart_web("web1", password)
    prompt("\nUpdate web2?")

    update_and_restart_web("web2", password)
    prompt("\nUpdate web3?")

    update_and_restart_web("web3", password)
  end

  desc "Update public from subversion on all web servers"
  task(:update_svn_view => :environment) do
    puts "Updating web1"
    result, conflicts = svn_up("web1", "public app/views")
    puts result.join("\n")

    puts "Updating web2"
    result, conflicts = svn_up("web2", "public app/views")
    puts result.join("\n")

    puts "Updating web3"
    result, conflicts = svn_up("web3", "public app/views")
    puts result.join("\n")
  end
end