Command_palette_background_color = {r=0.6, g=0.8, b=0.6}
Command_palette_border_color = {r=0.6, g=0.7, b=0.6}
Command_palette_command_color = {r=0.2, g=0.2, b=0.2}
Command_palette_alternatives_color = {r=0.3, g=0.5, b=0.3}

  Commands = {
    'recent changes',
    'edit note at cursor',
    'reload note at cursor from disk',
    'search (all notes)',
    '/ (find on screen)',
  }

  end
  if Display_settings.mode == 'palette' then
    draw_command_palette()

  local pane = Surface[Cursor_pane.col][Cursor_pane.row]
  if pane.show_cursor then
    return edit.textinput(pane, t)

  if Display_settings.mode == nil then
    local pane = Surface[Cursor_pane.col][Cursor_pane.row]
    if pane.show_cursor then
      return edit.textinput(pane, t)
    end
  elseif Display_settings.mode == 'palette' then
    Display_settings.palette = Display_settings.palette..t
    Display_settings.palette_text = App.newText(love.graphics.getFont(), Display_settings.palette)
  else
    print(Display_settings.mode)
    assert(false)

  if Display_settings.mode == nil then
    handle_normal_mode_keychord(chord, key)
  elseif Display_settings.mode == 'palette' then
    handle_command_palette_keychord(chord, key)
  else
    print(Display_settings.mode)
    assert(false)
  end
end
function handle_command_palette_keychord(chord, key)
  if chord == 'escape' then
    Display_settings.mode = nil
  elseif chord == 'backspace' then
    local len = utf8.len(Display_settings.palette)
    local byte_offset = Text.offset(Display_settings.palette, len)
    Display_settings.palette = string.sub(Display_settings.palette, 1, byte_offset-1)
    Display_settings.palette_text = App.newText(love.graphics.getFont(), Display_settings.palette)
  elseif chord == 'return' then
    -- TODO: handle search command
    local options = options()
    if #options > 0 then
      -- TODO
      print(options[1])
    end
    Display_settings.mode = nil
  end
end
function draw_command_palette()
  local pwidth,pheight = 400, 300
  local left = math.max(App.screen.width/2-pwidth/2, 0)
  local top = math.max(App.screen.height/2-pheight/2, 0)
  local width = math.min(pwidth, App.screen.width)
  local height = math.min(pheight, App.screen.height)
  -- background
  App.color(Command_palette_background_color)
  love.graphics.rectangle('fill', left, top, width, height, 10, 10)  -- rounded corners
  App.color(Command_palette_border_color)
  love.graphics.rectangle('line', left, top, width, height, 10, 10)  -- rounded corners
  love.graphics.line(left, top+5+Line_height+5, left+width, top+5+Line_height+5)
  -- input box
  App.color(Command_palette_command_color)
  draw_palette_input(left+10, top+5)
  -- alternatives
  App.color(Command_palette_alternatives_color)
  local y = top+5+Line_height+5+5
  for _,cmd in ipairs(options()) do
    love.graphics.print(cmd, left+5,y)
    y = y+Line_height
    if y >= top+height then
      break
    end
  end
end
function draw_palette_input(x, y)
  love.graphics.draw(Display_settings.palette_text, x,y)
  x = x+App.width(Display_settings.palette_text)
  draw_cursor(x, y)
end
function draw_cursor(x, y)
  -- blink every 0.5s
  if math.floor(Cursor_time*2)%2 == 0 then
    App.color(Cursor_color)
    love.graphics.rectangle('fill', x,y, 3,Line_height)
  end
end
function options()
  if Display_settings.palette == '' then
    return Commands
  elseif Display_settings.palette:sub(1,1) == '/' then
    return {}
  else
    local results = filter_options(Commands, Display_settings.palette)
    append(results, file_options(Display_settings.palette))
    return results
  end
end
function filter_options(candidates, prefix)
  local result = {}
  for _,cand in ipairs(candidates) do
    if cand:find(prefix) == 1 then
      table.insert(result, cand)
    end
  end
  return result
end
function file_options(prefix)
  local path = Directory
  local dir = dirname(prefix)
  local visible_dir = dir
  if dir ~= './' then
    path = path..'/'..dir
  else
    visible_dir = ''
  end
  local files = love.filesystem.getDirectoryItems(path)
  local base = basename(prefix)
  return concat_all(visible_dir, filter_options(reorder(path, files), base))
end
function reorder(dir, files)
  local result = {}
  local info = {}
  for _,file in ipairs(files) do
    info[file] = love.filesystem.getInfo(dir..'/'..file)
  end
  -- files before directories
  for _,file in ipairs(files) do
    if info[file].type ~= 'directory' then
      table.insert(result, file)
    end
  end
  for _,file in ipairs(files) do
    if info[file].type == 'directory' then
      table.insert(result, file..'/')
    end
  end
  return result
end
function handle_normal_mode_keychord(chord, key)

  if chord == 'return' then
    Display_settings.mode = 'palette'
    return
  end

function concat_all(dir, files)
  if dir == '' then return files end
  for i,file in ipairs(files) do
    files[i] = dir..file
  end
  return files
end
function append(arr, b)
  for _,x in ipairs(b) do
    table.insert(arr, x)
  end
end

end
function dirname(path)
  return path:match('.*[/\\]') or './'

function test_dirname()
  check_eq(dirname('a/b'), 'a/', 'F - test_dirname')
  check_eq(dirname('x'), './', 'F - test_dirname/current')
end
function basename(path)
  return string.gsub(path, ".*/(.*)", "%1")
end