Lua tableDump API

--TableDump for lua, takes a table and a filename, writes the table to the file in a easy-to-read format. Not designed to be reversed

--[[
Copyright 2017 Stekeblad

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
]]

-----------------------------------

-- Possible future features: maxDepth, don't allow tables nested deeper then x levels
--                           protection against recursion, a={b={c=a}} --> a==a.b.c==a.b.c.b.c

-- For customization, the functions indent and niceColumns can be changed for different intentation length and column width

local depth
local handle

local function indent()
  for i=0, depth*3, 1 do
    handle:write(" ")
  end
end

local function niceColumns(key)
  handle:write(key)
  for i = 20 - string.len(key), 0, -1 do
    handle:write(" ")
  end
end

local function tableBreakdown(tab)
  handle:write("\n")
  indent()
  handle:write("{")
  depth = depth + 1
  local firstPair = true
  for key, val in pairs(tab) do
    if not firstPair then
      handle:write(",\n")
    else
      firstPair = false
      handle:write("\n")
    end
    if (type(val) == "table") then
      indent()
      handle:write(key)
      tableBreakdown(val)
    else
      indent()
      niceColumns(key)

      if (type(val) == "boolean") then
        if val then
          handle:write("true")
        else
          handle:write("false")
        end
      elseif (type(val) == "number") then
        handle:write(val)
      elseif (type(val) == "string") then
        handle:write("\"" .. val .. "\"")
      else
        handle:write("[" .. string.upper(type(val)) .. "]")
      end
    end
  end
  handle:write("\n")
  depth = depth - 1
  indent()
  handle:write("}")
end

function tableDump(tab, fileName)
  handle = io.open(fileName, "w")
  depth = 0
  if not handle then error("tableDump: Failed to open file for writing", 2) end
  tableBreakdown(tab)
  handle:close()
  return true
end