-----------------------------------------------------------------------------------------
--
-- Defaults load /save example
-- Jeff Tullin 2012
----------------------------------------------------------------------------------------- 
 
require ("json")
_G.lobal = {}
_G.prefsFile = "Defaults.json"
 
 
function setDefaults()
 
   --in this function, set up the defaults for all 
   --the global state variables
 
   print ("Initialising")
   _G.lobal["userName"] = "Fred"
   _G.lobal["currentLevel"] = 6
 
end
 
function addDefaultItem(itemName, theValue)
   --this function allows you to add a new state variable
   --if one turns out to be needed later on
   print ("Initialising")
   _G.lobal[itemName] = theValue
end
 
function saveDefaults()
   --call this on application suspend or application exit
   print ("saving defaults")
   local path = system.pathForFile( _G.prefsFile, system.DocumentsDirectory )
   local file = io.open( path, "w" )
   local contents = json.encode(_G.lobal)
   file:write(contents)
   io.close( file )
end
 
 
function loadDefaults()
   --reload saved file
   print ("loading state")
 
   --set defaults first in case the file is missing
   setDefaults()
 
   local path = system.pathForFile( _G.prefsFile, system.DocumentsDirectory )
 
   local file = io.open( path, "r" )
   --will be nil if it does not exist
 
   if file then
        -- read all contents of file into a string
        local contents = file:read( "*a" )
        _G.lobal = json.decode(contents)
        io.close( file )
   else
     print ("file not found")
   end
 
end
 
 
 
--test the system
-- to make use of this system, there is a truly global table called lobal
-- it contains as many elements as you want
-- you can initialise them en masse in the setDefaults() function
-- or one by one with the addDefaultItem(itemName, theValue)  function
 
--when the app suspends or exits, save the file with saveDefaults()
--when the app starts or resumes, use loadDefaults()
 
--using the variables is simple using the syntactic sugar version
 
--   _G.lobal.myVariable = 6   (see what I did there??)
 
 
 
 
setDefaults()
addDefaultItem("highScore", 999)
 
--change a default to some new value
_G.lobal.currentLevel = 9
--save it
saveDefaults()
--reload it
loadDefaults()