--[[
Sliding option handler [v1] (13/08/2018)
Written by AFRLme [Lee Clarke]
-- + --
afrlme@outlook.com | https://de.tail.studio
-- + --
This script was created as freelance work for (game name) [developer name]. In game credit is non-negotiable.
You are free to: ¹ use it in your game(s). ² modify the script.
Do not remove - or edit - this comment block.
--]]

-- * local vars for storing data * --
local rail, anim, width, perc, pos, loop

-- * table for storing objects, interaction polygons, begin & end slider rail positions * --
sliders = {
 { obj = Objects["slider_music"].ObjectPolygon, b = 64, e = 864 },
 { obj = Objects["slider_sound"].ObjectPolygon, b = 64, e = 864 }
}

-- * sound tables for volume slider * --
vol_sndz = { sfx = "vispath:Sounds/Character/Yeah.ogg" }

function slider_sound()
 if rail == 2 then startSound(vol_sndz["sfx"], {flags = 1, volume = getVolume(eSoundVolume)}) end -- play sfx on sound volume change or lose focus
 loop = nil; anim = nil; rail = nil -- reset some variables
 Conditions["options_modified"].ConditionValue = true -- set options_modified condition to true to signify an option has been changed (will be used to determine if config.ini should be updated)
end

-- * function that handles mouse events * --
function onMouseEvent(typ, pos)
 if game.CurrentScene:getName() == "options_menu" then -- force it to only register events for settings scene

  if typ == eEvtMouseLeftButtonHolding then
    for i = 1, #sliders do
     if isPointInsidePolygon(getCursorPos(), sliders[i].obj) then rail = i; if loop == nil then registerEventHandler("mainLoop", "updateSlider"); loop = true end end
    end
  elseif typ == eEvtMouseLeftButtonHold then
   slider_sound(); unregisterEventHandler("mainLoop", "updateSlider")
  end

 end
end

function updateSlider()
 if rail ~= nil then
  pos = getCursorPos().x; if pos  sliders[rail].e then pos = sliders[rail].e end
  perc = math.floor( (getCursorPos().x - sliders[rail].b) / (sliders[rail].e - sliders[rail].b) * 100 ) -- convert mouse position on rail to percentage value
  if perc  100 then perc = 100 end -- fallback in case percentage lower than 0 or higher than 100
  if not isPointInsidePolygon(getCursorPos(), sliders[rail].obj) then slider_sound(); unregisterEventHandler("mainLoop", "updateSlider") end
  if rail == 1 then
   setVolume(eMusicVolume, perc) -- update music volume
  elseif rail == 2 then
   setVolume(eSoundVolume, perc) -- update sound volume
  end
  anim = ActiveAnimations["vol_"..rail] -- get animation current position
  anim.AnimationCurrentPosition = {x = (pos - 23) , y = anim.AnimationCurrentPosition.y} -- update rail handle position
  if anim.AnimationCurrentPosition.x  sliders[rail].e then anim.AnimationCurrentPosition = {x = (sliders[rail].e - 23), y = anim.AnimationCurrentPosition.y} end
 end
end

registerEventHandler("mouseEvent", "onMouseEvent") -- creates an event listener & assigns it to a function "onMouseEvent" to handle mouse events