--NOPROCESSING
----------------------------------------------
-- Pickle.lua
-- A table serialization utility for lua
-- Steve Dekorte, http://www.dekorte.com, Apr 2000
-- Freeware
----------------------------------------------


function pickle(t)
  return Pickle:clone():pickle_(t)
end

Pickle = {
	clone = function (t) local nt={}; for i, v in pairs(t) do nt[i]=v end return nt end 
}

function Pickle:pickle_(root)
	if type(root) ~= "table" then 
		error("can only pickle tables, not ".. type(root).."s")
	end
	self._tableToRef = {}
	self._refToTable = {}
	local savecount = 0
	self:ref_(root)
	local s = ""
	while #(self._refToTable) > savecount do
		savecount = savecount + 1
		local t = self._refToTable[savecount]
		s = s.."{\n"
		for i, v in pairs(t) do
			s = string.format("%s[%s]=%s,\n", s, self:value_(i), self:value_(v))
		end
		s = s.."},\n"
	end
	
	return string.format("{%s}", s)
end

function Pickle:value_(v)
	local vtype = type(v)
	if     vtype == "string" then return string.format("%q", v)
	elseif vtype == "number" then return v
	elseif vtype == "table" then return "{"..self:ref_(v).."}"
	else --error("pickle a "..type(v).." is not supported")
	end  
end

function Pickle:ref_(t)
	local ref = self._tableToRef[t]
	if not ref then 
		if t == self then error("can't pickle the pickle class") end
		table.insert(self._refToTable, t)
		ref = #(self._refToTable)
		self._tableToRef[t] = ref
	end
	return ref
end

----------------------------------------------
-- unpickle
----------------------------------------------

function unpickle(s)
	if type(s) ~= "string" then
		error("can't unpickle a "..type(s)..", only strings")
	end
	local gentables = loadstring("return "..s)
	local tables = gentables()
  
	for tnum = 1, #(tables) do
		local t = tables[tnum]
		local tcopy = {}; for i, v in pairs(t) do tcopy[i] = v end
		for i, v in pairs(tcopy) do
			local ni, nv
			if type(i) == "table" then ni = tables[i[1]] else ni = i end
			if type(v) == "table" then nv = tables[v[1]] else nv = v end
			t[i] = nil
			t[ni] = nv
		end
	end
	return tables[1]
end
