class Sus::Output::Lines

def []= index, line
	@lines[index] = line
	
	redraw(index)
end

def clear
	@lines.clear
	write
end

def height
	@output.size.first
end

def initialize(output)
	@output = output
	@lines = []
	
	@current_count = 0
end

def origin
	if @current_count > 0
		@output.write("\e[#{@current_count}F\e[J")
	end
	
	@current_count = 0
end

def redraw(index)
	if index < @current_count
		update(index, @lines[index])
	else
		write
	end
end

def soft_wrap
	@output.write("\e[?7l")
	
	yield
ensure
	@output.write("\e[?7h")
end

def update(index, line)
	offset = @current_count - index
	
	@output.write("\e[#{offset}F\e[K")
	
	soft_wrap do
		line.print(@output)
	end
	
	if offset > 1
		@output.write("\e[#{offset-1}E")
	end
end

def write
	origin
	
	height = self.height
	
	soft_wrap do
		@lines.each do |line|
			break if (@current_count+1) >= height
			
			if line
				line.print(@output)
			else
				@output.puts
			end
			
			@current_count += 1
		end
	end
end