-------------------------------------------------------------------------------
-- Copyright (c) 2012 Sierra Wireless and others.
-- All rights reserved. This program and the accompanying materials
-- are made available under the terms of the Eclipse Public License v1.0
-- which accompanies this distribution, and is available at
-- http://www.eclipse.org/legal/epl-v10.html
--
-- Contributors:
--     Sierra Wireless - initial API and implementation
-------------------------------------------------------------------------------

--- @module xmlformatter
local M = {}

local nodetostring ={}-- a map (key=NODE_TYPE, value=conversion function)

-- convert xml to table
local function xmltotable(domtable,result,indent,indentlevel)
  local f = nodetostring[domtable._type]
  if f then return f(domtable,result,indent,indentlevel) end
  return nil
end

-- print ROOT in table
local function roottotable(domtable,result,indent,indentlevel)
  for i,child in ipairs(domtable._children) do
    xmltotable(child,result,indent,indentlevel)
  end
  return result
end

-- print ELEMENT in table
local function elementtotable(domtable,result,indent,indentlevel)
  -- detect if this element has children
  local havechildren = domtable._children and (#(domtable._children) > 0)

  -- indent if needed
  if indent then
    result[#result+1] = "\n"
    result[#result+1] = string.rep("   ",indentlevel)
  end

  -- open  element
  result[#result+1] = "<"
  result[#result+1] = domtable._name

  -- print attributes
  if domtable._attr then
    for id, val in pairs(domtable._attr) do
      result[#result+1] = " "
      result[#result+1] = id
      result[#result+1] = "=\""
      result[#result+1] = val
      result[#result+1] = "\""
    end
  end

  -- auto close balise if needed
  if havechildren then
    result[#result+1] = ">"
  else
    result[#result+1] = "/>"
  end

  -- do not indent in a pre balise
  indent = indent and domtable._name ~= "pre"
  local indentnext = true

  -- print children
  if havechildren then
    for i,child in ipairs(domtable._children) do
      xmltotable(child,result,indent and indentnext,indentlevel+1)
      indentnext = child._type ~= "TEXT"
    end
  end

  -- close element
  if havechildren then
    if indent and indentnext then
      result[#result+1] = "\n"
      result[#result+1] = string.rep("   ",indentlevel)
    end
    result[#result+1] = "</"
    result[#result+1] = domtable._name
    result[#result+1] = ">"
  end

  return result
end

-- print TEXT in table
local function texttotable(domtable,result,indent,indentlevel)
  -- just print the text
  result[#result+1] =  domtable._text

  return result
end


nodetostring.ROOT=roottotable
nodetostring.ELEMENT=elementtotable
nodetostring.TEXT=texttotable

----------------------------------------------
-- @function [parent=#xmlformatter] xmltostring
-- @param #table domtable return by domhandler
function M.xmltostring(domtable)
  local result = xmltotable(domtable,{},true,0)
  return table.concat(result);
end

return M