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-- info
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function gadget:GetInfo()
  return {
    name      = "CrosstalkGadget",
    desc      = "Example of gadget<->widget communication.",
    author    = "SpliFF",
    date      = "Sept, 2009",
    license   = "GNU GPL, v2 or later",
    layer     = 0,
    enabled   = true  --  loaded by default?
  }
end

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-- about
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-- This little demo gadget shows how to pass data to a widget. The concept is fairly
-- simple but the techniques are not obvious.
--
-- Synced code must always run the same on all computers. However sometimes you
-- might wish only some players to get feedback from a synced event. In most cases it is enough
-- to pass the data to the unsynced part of the gadget via 'SendToUnsynced'. However in a
-- few situations you may want a widget to deal with the data instead. This code demonstrates
-- that you can acheive that by first passing the data to unsynced and *then* sending it to the widget.
-- In short we use the unsynced code as a proxy to pass the request.
--
-- To receive data a widget must first register an interest. CrosstalkWidget is a widget
-- that demonstrates the widget side of the message passing. 

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if (gadgetHandler:IsSyncedCode()) then -- synced (all players)
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function gadget:GameFrame(f)
	if (f%320) == 0 then
		-- Send the data to the gadget's unsynced section. We can't send to LuaUI directly from synced code.
		SendToUnsynced('SendToWidget', 'hi', 'there')  -- func name, arg1, arg2, etc...
	end
end

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else -- unsynced (this player)
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-- Called from gadget synced. This is our proxy to pass the data on to the widget.
local function SendToWidget(_, msg1, msg2)
	-- Make sure the widget function is still registered. The widget may have been stopped.
	if (Script.LuaUI('WidgetUpdate')) then
		-- Call the widget function. Widget must declare 'Update' this via 'widgetHandler:RegisterGlobal'
		Script.LuaUI.WidgetUpdate(msg1, msg2) -- arg1, arg2, etc...
	end
end

function gadget:Initialize()
	-- Register a function for 'SendToUnsynced'.
	gadgetHandler:AddSyncAction("SendToWidget", SendToWidget)
end

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end -- of synced/unsynced
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