Simple ML script to cycle through different ML menu states

Cycler.lua

--[[ 	
    Cycler

    [PLAY]+[Anykey, eg half shutter press] = null/reset [PLAY]
    [PLAY]+{various button_delays}+[PLAY] =  additional functionality as displayed in top bar

    Note: functionally is temporally enhanced after pressing [PLAY], by waiting to see additional options appear then pressing [PLAY] to select

	Version 0.42
	Garry George March  2019
	http://photography.grayheron.net/
--]]																							

config = 1 -- cam start configuration state
max_config = 6 -- adjust if you add additional states
button = KEY.PLAY -- or KEY.INFO or KEY.MENU etc
cycled = false
timer = dryos.ms_clock
timer_running = false
direction = 1
bookmark_apex = 10 -- Apex shutter value for (dark) bookmark, could be 11 or 12 etc. Note script auto resets the shutter after a bookmark image
current_shutter = camera.shutter.apex
del = {1000, 3000, 5000} -- Provide four time-based options in ms, ie 0-del[1], del[1]-del[2], del[2]-del[3], >del[3]
time_now = 0
count = dryos.shooting_card.file_number

-- start by nulling out menu items to control
menu.set("Expo","Auto ETTR",0)
menu.set("Shoot","Advanced Bracket",0)
menu.set("Expo","Dual ISO",0)
menu.set("Overlay","Magic Zoom",0)
menu.set("Overlay","Waveform",0)

-- add additional menu state changes here + adjust max_config value

function property.SHUTTER:handler(value) -- keep track of current shutter value for bookmark reset
    if camera.shutter.apex ~= bookmark_apex then current_shutter = camera.shutter.apex end
end

function reset(k)
    if cycled then
        if config == 1 then -- reset everything
            menu.set("Expo","Auto ETTR",0)
            menu.set("Shoot","Advanced Bracket",0)
            menu.set("Expo","Dual ISO",0)
            menu.set("Overlay","Magic Zoom",0)
            menu.set("Overlay","Waveform",0)
            display.clear()
        elseif config == 2 then -- switch to ETTR
        menu.set("Shoot","Advanced Bracket",0)
            menu.set("Expo","Auto ETTR",1) 
        elseif config == 3 then -- switch to bracketing
            menu.set("Expo","Auto ETTR",0)
            menu.set("Overlay","Magic Zoom",0)
            menu.set("Shoot","Advanced Bracket",1)
        elseif config == 4 then -- switch to Magic Zoom
            menu.set("Shoot","Advanced Bracket",0)
            menu.set("Expo","Dual ISO",0)
            menu.set("Overlay","Magic Zoom",1)
        elseif config == 5 then -- switch to Dual ISO
            menu.set("Overlay","Magic Zoom",0)
            menu.set("Overlay","Waveform",0)
            display.clear()
            menu.set("Expo","Dual ISO",1)
        elseif config == 6 then -- switch to Waveform
            menu.set("Expo","Dual ISO",0)
            menu.set("Overlay","Waveform",1)
        -- add other state changes here
        -- elseif config == 7 etc
        end
        cycled = false
    end
end
 
function test4reset(k)
    if dryos.shooting_card.file_number ~= count then -- check after image captured
        if camera.shutter.apex == bookmark_apex then camera.shutter.apex = current_shutter end -- reset shutter after bookmark taken
        count = dryos.shooting_card.file_number
    end
    if k == button then
        if timer_running then -- second press of [PLAY] in sequence
            timer_running = false
            if time_now - timer > del[3] then -- normal button action
                cycled = false
                return true
            elseif (time_now - timer > del[2]) and (time_now - timer < del[3]) then -- reverse direction
                cycled = false
                direction = -direction
                return false
            elseif time_now - timer > del[1] then -- (re)set/toogle bookmark_apex
                cycled = false
                count = dryos.shooting_card.file_number
                if camera.shutter.apex == bookmark_apex then 
                    camera.shutter.apex = current_shutter
                else 
                    camera.shutter.apex = bookmark_apex 
                end
                return false
            else
                config = config + direction
                if config > max_config then config = 1 end
                if config < 1 then config = max_config end
                cycled = true
                return false
            end
        else -- first press of [PLAY] in potential sequence
            timer = dryos.ms_clock
            timer_running = true
            cycled = false
            return false
        end
        
    end
    cycled = false
    timer_running = false
    return true
end

lv.info
{
    name = "Cycler State",
    value = "",
    priority = 100,
    update = function(this)
        time_now = dryos.ms_clock
        this.background = COLOR.WHITE
        if direction == 1 then this.foreground = COLOR.BLACK else this.foreground = COLOR.RED end
        if timer_running and (time_now - timer > del[2]) and (time_now - timer < del[3]) then 
            this.foreground = COLOR.BLACK
            this.value = "<<>>"
        elseif timer_running and (time_now - timer > del[1]) and (time_now - timer < del[2]) then 
            this.foreground = COLOR.BLACK
            this.value = "BOOK"
        elseif timer_running and (time_now - timer > del[3]) then 
            this.foreground = COLOR.BLACK
            this.value = "PLAY"
        else
            if config == 1 then
                this.value = "NULL"
            elseif config == 2 then 
                this.value = "ETTR"
            elseif config == 3 then
                this.value = "AUTO"
            elseif config == 4 then
                this.value = "ZOOM"
            elseif config == 5 then
                this.value = "DISO"
            elseif config == 6 then
                this.value = "WAVE"
            -- add additional info here, ie four capital letters for consistancy
            end
        end
    end
}

event.shoot_task = reset
event.keypress = test4reset