require File.dirname(__FILE__) + '/../test_helper'

class MessageTest < ActiveSupport::TestCase
  api_fixtures
  fixtures :messages

  EURO = "\xe2\x82\xac" #euro symbol

  # This needs to be updated when new fixtures are added
  # or removed.
  def test_check_message_count
    assert_equal 2, Message.count
  end

  def test_check_empty_message_fails
    message = Message.new
    assert !message.valid?
    assert message.errors.invalid?(:title)
    assert message.errors.invalid?(:body)
    assert message.errors.invalid?(:sent_on)
    assert true, message.message_read
  end
  
  def test_validating_msgs
    message = messages(:one)
    assert message.valid?
    massage = messages(:two)
    assert message.valid?
  end
  
  def test_invalid_send_recipient
    message = messages(:one)
    message.sender = nil
    message.recipient = nil
    assert !message.valid?

    assert_raise(ActiveRecord::RecordNotFound) { User.find(0) }
    message.from_user_id = 0
    message.to_user_id = 0
    assert_raise(ActiveRecord::RecordInvalid) {message.save!}
  end

  def test_utf8_roundtrip
    (1..255).each do |i|
      assert_message_ok('c', i)
      assert_message_ok(EURO, i)
    end
  end

  def test_length_oversize
    assert_raise(ActiveRecord::RecordInvalid) { make_message('c', 256).save! }
    assert_raise(ActiveRecord::RecordInvalid) { make_message(EURO, 256).save! }
  end

  def test_invalid_utf8
    # See e.g http://en.wikipedia.org/wiki/UTF-8 for byte sequences
    # FIXME - Invalid Unicode characters can still be encoded into "valid" utf-8 byte sequences - maybe check this too?
    invalid_sequences = ["\xC0",         # always invalid utf8
                         "\xC2\x4a",     # 2-byte multibyte identifier, followed by plain ASCII
                         "\xC2\xC2",     # 2-byte multibyte identifier, followed by another one
                         "\x4a\x82",     # plain ASCII, followed by multibyte continuation
                         "\x82\x82",     # multibyte continuations without multibyte identifier
                         "\xe1\x82\x4a", # three-byte identifier, contination and (incorrectly) plain ASCII
                        ]
    invalid_sequences.each do |char|
      begin
        # create a message and save to the database
        msg = make_message(char, 1)
        # if the save throws, thats fine and the test should pass, as we're
        # only testing invalid sequences anyway.
        msg.save! 

        # get the saved message back and check that it is identical - i.e: 
        # its OK to accept invalid UTF-8 as long as we return it unmodified.
        db_msg = msg.class.find(msg.id)
        assert_equal char, db_msg.title, "Database silently truncated message title"

      rescue ActiveRecord::RecordInvalid
        # because we only test invalid sequences it is OK to barf on them
      end
    end
  end  

  def make_message(char, count)
    message = messages(:one)
    message.title = char * count
    return message
  end

  def assert_message_ok(char, count)
    message = make_message(char, count)
    assert message.save!
    response = message.class.find(message.id) # stand by for some über-generalisation...
    assert_equal char * count, response.title, "message with #{count} #{char} chars (i.e. #{char.length*count} bytes) fails"
  end

end
