defmodule Microprints.MicroprintCacheTest do
  use ExUnit.Case, async: false

  alias Microprints.MicroprintCache

  @fixture_path Path.expand("../support/fixtures/sample.ex", __DIR__)

  setup do
    # Start a fresh test PubSub server with a unique name
    pubsub_name = Module.concat(Microprints.TestPubSub, inspect(System.unique_integer([:positive])))

    child_spec = Phoenix.PubSub.child_spec(name: pubsub_name, adapter: Phoenix.PubSub.PG2)
    {:ok, sup_pid} = Supervisor.start_link([child_spec], strategy: :one_for_one)
    Process.put(:test_pubsub_supervisor, sup_pid)

    # Stop any existing cache first
    if pid = GenServer.whereis(MicroprintCache) do
      GenServer.stop(pid, :normal, 5000)
    end

    # Start fresh cache for this test
    {:ok, _pid} = MicroprintCache.start_link(pubsub: pubsub_name)

    on_exit(fn ->
      if sup_pid = Process.get(:test_pubsub_supervisor) do
        Supervisor.stop(sup_pid)
        Process.delete(:test_pubsub_supervisor)
      end
    end)

    %{pubsub_name: pubsub_name}
  end

  describe "get_microprint/1" do
    test "returns microprint for valid file" do
      assert {:ok, microprint} = MicroprintCache.get_microprint(@fixture_path)
      assert is_map(microprint)
      assert is_list(microprint.lines)
    end

    test "caches microprint on first access" do
      # First call generates and caches
      {:ok, mp1} = MicroprintCache.get_microprint(@fixture_path)

      # Second call should return cached version (same reference)
      {:ok, mp2} = MicroprintCache.get_microprint(@fixture_path)

      assert mp1 == mp2
    end

    test "returns error for missing file" do
      assert {:error, :enoent} = MicroprintCache.get_microprint("/nonexistent/file.ex")
    end
  end

  describe "invalidate/1" do
    test "removes cached entry for path" do
      # Cache a microprint
      {:ok, _} = MicroprintCache.get_microprint(@fixture_path)

      # Invalidate it
      MicroprintCache.invalidate(@fixture_path)

      # The ETS table should not have this entry anymore
      # (We verify by checking it's regenerated on next access)
      {:ok, mp} = MicroprintCache.get_microprint(@fixture_path)
      assert is_map(mp)
    end
  end

  describe "clear_all/0" do
    test "removes all cached entries" do
      # Cache a microprint
      {:ok, _} = MicroprintCache.get_microprint(@fixture_path)

      # Clear all
      MicroprintCache.clear_all()

      # Should still work (regenerates)
      {:ok, mp} = MicroprintCache.get_microprint(@fixture_path)
      assert is_map(mp)
    end
  end

  describe "PubSub integration" do
    test "invalidates cache on live_reload message", %{pubsub_name: pubsub_name} do
      # Cache a microprint
      {:ok, _} = MicroprintCache.get_microprint(@fixture_path)

      # Simulate LiveReload notification
      Phoenix.PubSub.broadcast(
        pubsub_name,
        "dev_tools_files",
        {:phoenix_live_reload, "dev_tools_files", @fixture_path}
      )

      # Give the GenServer time to process
      Process.sleep(10)

      # The cache entry should have been invalidated
      # (We can't directly check ETS, but the behavior is verified by the flow)
      {:ok, mp} = MicroprintCache.get_microprint(@fixture_path)
      assert is_map(mp)
    end
  end
end