class LLencError < StandardError
	def initialize(msg) @msg = msg end
	def to_s() return @msg end
end

class LLenc

	def initialize socket
		@socket = socket
		@read_timeout = @write_timeout = 24 * 3600
		@ip = @socket.peeraddr[3]
	end

	def set_timeout time
		@read_timeout = @write_timeout = time
	end

	def peeraddr
		return @socket.peeraddr
	end

	def write datas
		
		timeout @write_timeout do
			dl = datas.length
			t_dl = dl.to_s

			if dl >= 10 then # Case 2

				l = []
				l[0] = t_dl.length + 64
				return @socket.write(l.pack('C') + t_dl + datas)

			else # Case 1
				return @socket.write(t_dl + datas)
			end
		end
	end

	def read

		timeout @read_timeout do
			dl = 0 # Data length

			l = @socket.read 1

			if l.nil?
				raise LLencError.new("1st l read error")
			end

			l = l.unpack 'C'

			if l[0] >= 48 and l[0] <= 57 then # Case 1
				dl = l[0] - 48

			else # Case 2
				if l[0] >= 65 and l[0] <= 90 then
					l = @socket.read(l[0] - 64)
					if l.nil?
						raise LLencError.new("2nd l read error")
					end
					l = l.unpack 'C*'

					l.each do |val|
						dl = dl * 10 + val - 48
					end
				else
					raise LLencError.new("invalid l")
				end
			end

			t = @socket.read dl
			if t.nil?
				raise LLencError.new("data read error")
			end
			return t
		end
	end
end