local async = {}

---@class cmp.AsyncThrottle
---@field public timeout number
---@field public stop function
---@field public __call function

---@param fn function
---@param timeout number
---@return cmp.AsyncThrottle
async.throttle = function(fn, timeout)
  local time = nil
  local timer = vim.loop.new_timer()
  return setmetatable({
    timeout = timeout,
    stop = function()
      time = nil
      timer:stop()
    end,
  }, {
    __call = function(self, ...)
      local args = { ... }

      if time == nil then
        time = vim.loop.now()
      end
      timer:stop()

      local delta = math.max(0, self.timeout - (vim.loop.now() - time))
      timer:start(
        delta,
        0,
        vim.schedule_wrap(function()
          time = nil
          fn(unpack(args))
        end)
      )
    end,
  })
end

---Create deduplicated callback
---@return function
async.dedup = function()
  local id = 0
  return function(callback)
    id = id + 1

    local current = id
    return function(...)
      if current == id then
        callback(...)
      end
    end
  end
end

return async