Acccount Elixir Practice with GenServer impl

account_gen_impl.ex

defmodule Account do
    use GenServer

    # Helper Methods
    def new do
        {_, acc} = start_link()
        acc
    end

    def deposit(account, amount) do
        GenServer.cast(account, {:deposit, amount})
    end

    def withdraw(account, amount) do
        GenServer.cast(account, {:withdraw, amount})
    end

    def balance(account) do
        GenServer.call(account, {:balance})
    end

    # callbacks 
    def start_link do
        GenServer.start_link(__MODULE__, :ok, [])
    end

    def init(:ok) do
        {:ok, 0}
    end

    def handle_cast({:withdraw, amount}, state) do
        new_state = state - amount
        {:noreply, new_state}
    end

    def handle_cast({:deposit, amount}, state) do
        new_state = state + amount
        {:noreply, new_state}
    end
    
    def handle_call({:balance}, _from, state) do
        {:reply, state, state}
    end
    
end