cc-mek-scada/scada-common/tcallbackdsp.lua
2022-10-21 15:15:56 -04:00

51 lines
1.5 KiB
Lua

--
-- Timer Callback Dispatcher
--
local log = require("scada-common.log")
local util = require("scada-common.util")
local tcallbackdsp = {}
local registry = {}
-- request a function to be called after the specified time
---@param time number seconds
---@param f function callback function
function tcallbackdsp.dispatch(time, f)
---@diagnostic disable-next-line: undefined-field
registry[os.startTimer(time)] = { callback = f }
end
-- request a function to be called after the specified time, aborting any registered instances of that function reference
---@param time number seconds
---@param f function callback function
function tcallbackdsp.dispatch_unique(time, f)
-- ignore if already registered
for timer, entry in pairs(registry) do
if entry.callback == f then
-- found an instance of this function reference, abort it
log.debug(util.c("TCD: aborting duplicate timer callback (timer: ", timer, ", function: ", f, ")"))
-- cancel event and remove from registry (even if it fires it won't call)
---@diagnostic disable-next-line: undefined-field
os.cancelTimer(timer)
registry[timer] = nil
end
end
---@diagnostic disable-next-line: undefined-field
registry[os.startTimer(time)] = { callback = f }
end
-- lookup a timer event and execute the callback if found
---@param event integer timer event timer ID
function tcallbackdsp.handle(event)
if registry[event] ~= nil then
registry[event].callback()
registry[event] = nil
end
end
return tcallbackdsp