timer.lua

--[[
    Modeled after garry's mod's timer implementation.

    http://wiki.garrysmod.com/page/Category:timer
]]

timer = {
    namedTimers = {},
    --[[
        active,
        delay,
        delayTimer, --dt gets added to it until it is delay
        repetitions,
        repetitionsDone, --gets added to each cycle,
        func,
    ]]
    simpleTimers = {},
    --[[
        delay,
        delayTimer, --dt gets added to it until it is delay
        func,
    ]]
}
--timer.namedTimers[identifier]
-- repetitions=0 for infinity
function timer.Adjust(identifier, delay, repetitions, func)
    if timer.namedTimers[identifier] then
        timer.namedTimers[identifier].delay = delay
        -- check for lower?
        timer.namedTimers[identifier].repetitions = repetitions
        -- check for lower?
        timer.namedTimers[identifier].func = func
        return true
    else
        return false
    end
end
timer.Check = timer.Update
function timer.Update(dt)
    for k,v in pairs(timer.namedTimers) do
        if v.active then
            v.delayTimer = v.delayTimer + dt
            if v.delayTimer >= v.delay then
                v.func()
                v.repetitionsDone = v.repetitionsDone + 1
                if v.repetitions ~= 0 and v.repetitionsDone >= v.repetitions then
                    timer.namedTimers[k] = nil
                else
                    v.delayTimer -= v.delay
                end
            end
        end
    end
    for k,v in pairs(timer.simpleTimers) do
        v.delayTimer = v.delayTimer + dt
        if v.delayTimer >= v.delay then
            v.func()
            timer.simpleTimers[k]=nil
        end
    end
end --[[internal: go through all functions and do whatever is done]]
function timer.Create(identifier, delay, repetitions, func)
    if delay <= 0 then return false end
    timer.namedTimers[identifier] = {
        active = false,
        delay = delay,
        delayTimer = delay,
        repetitions = repetitions or 0,
        repetitionsDone = repetitions or 0,
        func = func
    }
end
function timer.Destroy(identifier)
    timer.namedTimers[identifier] = nil
end
function timer.Exists(identifier)
    return timer.namedTimers[identifier]~=nil
end
function timer.Pause(identifier)
    if timer.namedTimers[identifier] and timer.namedTimers[identifier].active then
        timer.namedTimers[identifier].active = false
        return true
    else
        return false
    end
end
timer.Remove = timer.Destroy
function timer.RepsLeft(identifier)
    if timer.namedTimers[identifier] then
        return timer.namedTimers[identifier].repetitionsLeft
    end
end
function timer.Simple(delay, func)
    table.insert(timer.simpleTimers, {delay=delay,delayTimer=0,func=func})
end
function timer.Start(identifier)
    if timer.namedTimers[identifier] then
        timer.namedTimers[identifier].active = true
        timer.namedTimers[identifier].delayTimer = 0
        timer.namedTimers[identifier].repetitionsDone = 0
        return true
    else
        return false
    end
end
function timer.Stop(identifier)
    if timer.namedTimers[identifier] and timer.namedTimers[identifier].active then
        timer.namedTimers[identifier].active = false
        timer.namedTimers[identifier].delayTimer = 0
        timer.namedTimers[identifier].repetitionsDone = 0
        return true
    else
        return false
    end
end
function timer.TimeLeft(identifier)
    if timer.namedTimers[identifier] then
        return timer.namedTimers[identifier].delay-timer.namedTimers[identifier].delayTimer
    else
        return 0
    end
end
function timer.Toggle(identifier)
    if timer.namedTimers[identifier] then
        if timer.namedTimers[identifier].active then
            timer.Pause(identifier)
        else
            timer.UnPause(identifier)
        end
        return timer.namedTimers[identifier].active
    end
end
function timer.UnPause(identifier)
    if timer.namedTimers[identifier] and not timer.namedTimers[identifier].active then
        timer.namedTimers[identifier].active = true
        return true
    else
        return false
    end
end