--?     if Surface[pane.column_index].name == 'search: donate' then
--?       print('draw: search: donate', pane, Display_settings.search_all_pane)
--?       print(#pane.lines, #pane.line_cache, pane._height)
--?       print(pane.lines[1].data)
--?     end

  end
  if Display_settings.mode == 'searching_all' then
    resume_search_all()

    Display_settings.mode = 'normal'

    interrupt_search_all()

    Display_settings.search_all_state = nil

    plan_draw()

    App.screen.print(Display_settings.search_all_most_recent_file, --[[x]] 5, --[[y]] Menu_status_bar_height+5)

    App.screen.print(Display_settings.search_all_progress_indicator, --[[x]] 5, --[[y]] Menu_status_bar_height+5)

    local search_term = string.match(column.name, 'search: (.+)')
    -- TODO

--?     print('column name', column.name)
    local search_all_term = string.match(column.name, 'search: (.+)')
--?     print('search term', search_all_term)
    populate_search_all_column(column, search_all_term)

  Display_settings.search_all_most_recent_file = ''

  Display_settings.search_all_progress_indicator = 'starting search...'

  local id = Display_settings.search_all_term:gsub('%W', '_')

  local id = id_for_search_all_pane(Display_settings.search_all_term)

  love.filesystem.remove(Directory..id)

end
function id_for_search_all_pane(term)
  return 'search/'..term:gsub('%W', '_')

function resume_search_all()
  -- make a little more progress towards searching the whole disk
  if Display_settings.search_all_state == nil then
    Display_settings.search_all_progress_indicator = 'initialized top-level files'
    Display_settings.search_all_state = {
      top_level_files = love.filesystem.getDirectoryItems(Directory),
      top_level_file_index = 1,
    }
  elseif Display_settings.search_all_state.top_level_file_index then
    local current_filename = Display_settings.search_all_state.top_level_files[Display_settings.search_all_state.top_level_file_index]
    Display_settings.search_all_progress_indicator = current_filename
    local info = love.filesystem.getInfo(Directory..current_filename)
    if info.type == 'file' then
--?       print('searching '..current_filename..' for '..Display_settings.search_all_term)
      local contents = love.filesystem.read(Directory..current_filename)
      local index = contents:find(Display_settings.search_all_term)
      if index then
        local id = id_for_search_all_pane(Display_settings.search_all_term)
        local snippet = contents:sub(math.max(1, index-100), math.min(#contents, index+100))
        local outfilename = Directory..id
        local success, errmsg = love.filesystem.append(outfilename, '[['..current_filename..']]\t')
        if not success then error(errmsg) end
        local success, errmsg = love.filesystem.append(outfilename, '...'..snippet..'...\n\n')
        if not success then error(errmsg) end
        load_from_disk(Cache[id])
        Display_settings.search_all_pane.lines = Cache[id].lines
        Text.redraw_all(Display_settings.search_all_pane)
      end
    end
    Display_settings.search_all_state.top_level_file_index = Display_settings.search_all_state.top_level_file_index+1
    if Display_settings.search_all_state.top_level_file_index > #Display_settings.search_all_state.top_level_files then
      Display_settings.search_all_state.top_level_file_index = nil
      Display_settings.search_all_state.top_level_files = nil
      Display_settings.search_all_state.time = os.time()
      Display_settings.search_all_state.year = os.date('%Y', Display_settings.search_all_state.time)
      Display_settings.search_all_state.date = os.date('%Y/%m/%d/', Display_settings.search_all_state.time)
    end
  elseif Display_settings.search_all_state.date then
    -- search one day's directory per frame
    -- stop when a whole year is missing
    Display_settings.search_all_progress_indicator = Display_settings.search_all_state.date
    local old_year = Display_settings.search_all_state.year
    local date_dir = Directory..Display_settings.search_all_state.date
    local info = love.filesystem.getInfo(date_dir)
    if info then
      if info.type == 'directory' then
        local files = love.filesystem.getDirectoryItems(date_dir)
        for _,file in ipairs(files) do
          print(date_dir..file)
        end
      end
    end
    Display_settings.search_all_state.time = Display_settings.search_all_state.time - 24*60*60
    Display_settings.search_all_state.year = os.date('%Y', Display_settings.search_all_state.time)
    Display_settings.search_all_state.date = os.date('%Y/%m/%d/', Display_settings.search_all_state.time)
    if old_year ~= Display_settings.search_all_state.year then
      local previous_year_info = love.filesystem.getInfo(Directory..Display_settings.search_all_state.year)
      if previous_year_info == nil then
        Display_settings.search_all_state = nil
        Display_settings.mode = 'normal'
      end
    end
  else
    assert(false, 'error in search state machine')
  end
end
function interrupt_search_all()
  if Display_settings.search_all_state then
    local id = id_for_search_all_pane(Display_settings.search_all_term)
    local outfilename = Directory..id
    local success, errmsg = love.filesystem.append(outfilename, 'interrupted at '..Display_settings.search_all_state.date..'\n')
    if not success then error(errmsg) end
    load_from_disk(Cache[id])
    Display_settings.search_all_pane.lines = Cache[id].lines
    Text.redraw_all(Display_settings.search_all_pane)
  end
  Display_settings.search_all_state = nil
  Display_settings.mode = 'normal'
end
function populate_search_all_column(column, search_all_term)
  local id = id_for_search_all_pane(search_all_term)
  table.insert(column, load_pane(id))
end