Section_stack = {}
Section_border_color = {r=0.7, g=0.7, b=0.7}

Section_border_padding_horizontal = 30  -- TODO: adjust this based on font height (because we draw text vertically along the borders
Section_border_padding_vertical = 15  -- TODO: adjust this based on font height

      line.section_stack = deepcopy(Section_stack)
    elseif line.data:match('\u{250c}') then
      line.section_stack = deepcopy(Section_stack)  -- as it is at the beginning
      local section_name = line.data:match('\u{250c}%s*(.*)')
      table.insert(Section_stack, section_name)
      line.section_begin = true
      line.section_name = section_name
      line.data = nil
    elseif line.data:match('\u{2518}') then
      local section_name = line.data:match('\u{2518}%s*(.*)')
      if array.find(Section_stack, section_name) then
        while table.remove(Section_stack) ~= section_name do
          --
        end
        line.section_end = true
        line.section_name = section_name
        line.data = nil
      end
      line.section_stack = deepcopy(Section_stack)
    else
      -- string
      line.section_stack = deepcopy(Section_stack)

  App.color(Text_color)

  local xleft, xright = State.left, State.right

    App.color(Text_color)

    if type(line.data) == 'string' then
      y = Text.draw(State, line_index, y, --[[startpos]] 1)

    xleft = render_stack_left_margin(State, line_index, line, y)
    xright = render_stack_right_margin(State, line_index, line, y)
    if line.section_name then
      App.color(Section_border_color)
      local section_text = to_text(line.section_name)
      if line.section_begin then
        love.graphics.line(xleft,y+Section_border_padding_vertical, xleft,y+State.line_height)
        love.graphics.line(xright,y+Section_border_padding_vertical, xright,y+State.line_height)
        love.graphics.line(xleft,y+Section_border_padding_vertical, xleft+50-2,y+Section_border_padding_vertical)
        love.graphics.draw(section_text, xleft+50,y)
        love.graphics.line(xleft+50+App.width(section_text)+2,y+Section_border_padding_vertical, xright,y+Section_border_padding_vertical)
      else assert(line.section_end)
        love.graphics.line(xleft,y-Section_border_padding_vertical, xleft,y+State.line_height-Section_border_padding_vertical)
        love.graphics.line(xright,y-Section_border_padding_vertical, xright,y+State.line_height-Section_border_padding_vertical)
        love.graphics.line(xleft,y+State.line_height-Section_border_padding_vertical, xleft+50-2,y+State.line_height-Section_border_padding_vertical)
        love.graphics.draw(section_text, xleft+50,y)
        love.graphics.line(xleft+50+App.width(section_text)+2,y+State.line_height-Section_border_padding_vertical, xright,y+State.line_height-Section_border_padding_vertical)
      end

--?       love.graphics.print('aaa', State.left, y)
--?       y = y + State.line_height
      line.height = debug_log_render[line.data.name](line.data, State.left, y, State.right-State.left)
      y = y + line.height

      if type(line.data) == 'string' then
        local old_left, old_right = State.left,State.right
        State.left,State.right = xleft,xright
        y = Text.draw(State, line_index, y, --[[startpos]] 1)
        State.left,State.right = old_left,old_right
        y = y + State.line_height
      else
        line.height = debug_log_render[line.data.name](line.data, xleft, y, xright-xleft)
        y = y + line.height
      end
    end
  end
end
function render_stack_left_margin(State, line_index, line, y)
  if line.section_stack == nil then
    -- assertion message
    for k,v in pairs(line) do
      print(k)
    end
  end
  App.color(Section_border_color)
  for i=1,#line.section_stack do
    local x = State.left + (i-1)*Section_border_padding_horizontal
    love.graphics.line(x,y, x,y+tenonauger.height(State, line_index))
    if y < 30 then
      love.graphics.print(line.section_stack[i], x+State.font_height+5, y+5, --[[vertically]] math.pi/2)
    end
    if y > App.screen.height-tenonauger.height(State, line_index) then
      love.graphics.print(line.section_stack[i], x+State.font_height+5, App.screen.height-App.width(to_text(line.section_stack[i]))-5, --[[vertically]] math.pi/2)
    end
  end
  return State.left + #line.section_stack*Section_border_padding_horizontal
end
function render_stack_right_margin(State, line_index, line, y)
  App.color(Section_border_color)
  for i=1,#line.section_stack do
    local x = State.right - (i-1)*Section_border_padding_horizontal
    love.graphics.line(x,y, x,y+tenonauger.height(State, line_index))
    if y < 30 then
      love.graphics.print(line.section_stack[i], x, y+5, --[[vertically]] math.pi/2)

    if y > App.screen.height-tenonauger.height(State, line_index) then
      love.graphics.print(line.section_stack[i], x, App.screen.height-App.width(to_text(line.section_stack[i]))-5, --[[vertically]] math.pi/2)
    end

  return State.right - #line.section_stack*Section_border_padding_horizontal

  if type(line.data) == 'string' then

  if line.data == nil then
    -- section header

  elseif type(line.data) == 'string' then
    return State.line_height

  -- a few text objects we can avoid recomputing unless the font changes
  Text_cache = {}

-- use this sparingly
function to_text(s)
  if Text_cache[s] == nil then
    Text_cache[s] = App.newText(love.graphics.getFont(), s)
  end
  return Text_cache[s]
end