module SimpleTimeout

# File lib/simple_timeout.rb, line 2
def self.timeout(seconds,timeout_error_class=SimpleTimeout::Error,wait_for_block=false,&block)
  if seconds == 0
    raise timeout_error_class.new, "execution expired"
  end

  if seconds.nil? || !seconds.is_a?(Numeric) || seconds < 0
    raise ArgumentError.new, "seconds must be an Integer number greater or equal to 0"
  end

  if block_given?
    control = SimpleTimeout::Control.new(seconds,timeout_error_class)

    block_thread = build_block_thread(control,&block)

    timeout_thread = build_timeout_thread(control)

    while control.status == :waiting;end
    
    timeout_thread.kill if timeout_thread.alive?
    block_thread.kill if block_thread.alive?

    if wait_for_block
      block_thread.join
    end

    handle_control_status control

  end
end

# File lib/simple_timeout.rb, line 48
def self.build_block_thread(control,&block)
  Thread.new(control) do |control|
    begin
      control.result = block.call
    rescue Exception => e
      control.error = e
    end
    control.mutex.synchronize do
      if control.status == :waiting
        control.status = :finished
      end
    end
  end
end

# File lib/simple_timeout.rb, line 63
def self.build_timeout_thread(control)
  Thread.new(control) do |control|
    sleep(control.timeout_in_seconds)
    control.mutex.synchronize do
      if control.status == :waiting
        control.status = :timeout
      end
    end
  end
end

# File lib/simple_timeout.rb, line 74
def self.handle_control_status(control)
  if control.status == :finished
    if control.error.nil?
      return control.result
    else
      raise control.error.class.new, control.error.message
    end
  else
    raise control.timeout_error_class.new, "execution expired"
  end
end