-- mod-version:3 --lite-xl 2.1
local config = require "core.config"
local style = require "core.style"
local DocView = require "core.docview"
local common = require "core.common"
local command = require "core.command"

config.plugins.linenumbers = common.merge({
  show = true,
  relative = false
}, config.plugins.linenumbers)

local draw_line_gutter = DocView.draw_line_gutter
local get_width = DocView.get_gutter_width

function DocView:draw_line_gutter(line, x, y, width)
  local lh = self:get_line_height()
  if
    not config.plugins.linenumbers.show
    and
    not config.plugins.linenumbers.relative
  then
    return lh
  end

  if config.plugins.linenumbers.relative then

    local color = style.line_number
    local local_idx = line
    local align = "right"

    local l1 = self.doc:get_selection(false)
    if line == l1 then
      color = style.line_number2
      if config.line_numbers then
        align = "center"
      else
        local_idx = 0
      end
    else
      local_idx = math.abs(line - l1)
    end

    -- Fix for old version (<=1.16)
    if width == nil then
      local gpad = style.padding.x * 2
      local gw = self:get_font():get_width(#self.doc.lines) + gpad
      width = gpad and gw - gpad or gw
    end

    common.draw_text(
      self:get_font(),
      color, local_idx, align,
      x + style.padding.x,
      y + self:get_line_text_y_offset(),
      width,  lh
    )
  else
    draw_line_gutter(self, line, x, y, width)
  end
  return lh
end

function DocView:get_gutter_width(...)
  if
    not config.plugins.linenumbers.show
    and
    not config.plugins.linenumbers.relative
  then
    return style.padding.x
  else
    return get_width(self, ...)
  end
end

command.add(nil, {
  ["line-numbers:toggle"]  = function()
    config.plugins.linenumbers.show = not config.plugins.linenumbers.show
  end,

  ["line-numbers:disable"] = function()
    config.plugins.linenumbers.show = false
  end,

  ["line-numbers:enable"]  = function()
    config.plugins.linenumbers.show = true
  end,

  ["relative-line-numbers:toggle"]  = function()
    config.plugins.linenumbers.relative = not config.plugins.linenumbers.relative
  end,

  ["relative-line-numbers:enable"]  = function()
    config.plugins.linenumbers.relative = true
  end,

  ["relative-line-numbers:disable"]  = function()
    config.plugins.linenumbers.relative = false
  end
})