local write_xml = require'luamml-xmlwriter'
local make_root = require'luamml-convert'.make_root
local save_result = require'luamml-tex'.save_result
local store_column = require'luamml-table'.store_column
local store_tag = require'luamml-table'.store_tag
local get_table = require'luamml-table'.get_table
local to_text = require'luamml-lr'

local properties = node.get_properties_table()

local funcid = luatexbase.new_luafunction'__luamml_amsmath_add_box_to_row:'
token.set_lua('__luamml_amsmath_add_box_to_row:', funcid, 'protected')
lua.get_functions_table()[funcid] = function()
  -- TODO: Error handling etc
  -- local box = token.scan_int()
  local boxnum = 0
  local startmath = tex.box[boxnum].list
  assert(startmath.id == node.id"math")
  store_column(startmath, true)
end

funcid = luatexbase.new_luafunction'__luamml_amsmath_finalize_table:'
token.set_lua('__luamml_amsmath_finalize_table:', funcid)
lua.get_functions_table()[funcid] = function()
  -- TODO: Error handling etc
  local mml_table = get_table()
  if not mml_table then return end
  mml_table.displaystyle = true
  local columns = node.count(node.id'align_record', tex.lists.align_head)//2
  mml_table.columnalign = string.rep('right left', columns, ' ')
  local spacing = {}
  for n in node.traverse_id(node.id'glue', tex.lists.align_head) do
    spacing[#spacing+1] = n.width == 0 and '0' or '.8em'
  end
  mml_table.columnspacing = table.concat(spacing, ' ', 2, #spacing-2)
  save_result(mml_table, true)
end

local last_tag

funcid = luatexbase.new_luafunction'__luamml_amsmath_save_tag:'
token.set_lua('__luamml_amsmath_save_tag:', funcid, 'protected')
lua.get_functions_table()[funcid] = function()
  local nest = tex.nest.top
  local chars = {}
  last_tag = to_text(nest.head)
end

funcid = luatexbase.new_luafunction'__luamml_amsmath_set_tag:'
token.set_lua('__luamml_amsmath_set_tag:', funcid, 'protected')
lua.get_functions_table()[funcid] = function()
  if not last_tag then
    texio.write_nl'WARNING: Tag extraction failed'
    return
  end
  store_tag({[0] = 'mtd', last_tag})
  last_tag = nil
end