--[[
 * ReaScript Name: Snap edit cursor to the nearest snap position
 * Description:
 * Instructions:
 * Author: AZ
 * Version: 1.0
--]]
reaper.Undo_BeginBlock()
reaper.PreventUIRefresh(1)

-- save current selection
local old_sel_items = {}
for i = 0, reaper.CountSelectedMediaItems(0)-1 do
  old_sel_items[i+1] = reaper.GetSelectedMediaItem(0, i)
end

reaper.Main_OnCommand(40142, 0) -- Insert empty item
reaper.Main_OnCommand(41184, 0) -- Snap to nearest snap point

empty = reaper.GetSelectedMediaItem(0, 0) -- get empty item
tr = reaper.GetMediaItem_Track(empty) -- need it for delete
time = reaper.GetMediaItemInfo_Value(empty, "D_POSITION") -- get position
reaper.SetEditCurPos(time, true, false) -- move edit cursor
reaper.DeleteTrackMediaItem(tr, empty) -- delete empty

-- restore saved selection
reaper.Main_OnCommand(40289, 0) -- Unselect all items
for _, item in ipairs(old_sel_items) do
  reaper.SetMediaItemSelected(item, true)
end

reaper.PreventUIRefresh(-1)
reaper.Undo_EndBlock("Snap edit cursor", -1)