defmodule Microwaveprop.Workers.Era5PollWorkerTest do
  use Microwaveprop.DataCase, async: false
  use Oban.Testing, repo: Microwaveprop.Repo

  alias Microwaveprop.Weather.Era5CdsJob
  alias Microwaveprop.Weather.Era5Client
  alias Microwaveprop.Workers.Era5PollWorker
  alias Microwaveprop.Workers.Era5SubmitWorker

  setup do
    System.put_env("ERA5_CDS_API_KEY", "test-key")
    on_exit(fn -> System.delete_env("ERA5_CDS_API_KEY") end)
    :ok
  end

  defp insert_cds_job(overrides \\ %{}) do
    # Default to "just now" so the stuck-after guard doesn't misfire
    # and re-submit in tests that want to exercise status-specific
    # branches. Tests that care about the stuck path pass a stale
    # submitted_at explicitly.
    fresh_submit = DateTime.truncate(DateTime.utc_now(), :second)

    attrs =
      Map.merge(
        %{
          year: 2014,
          month: 3,
          tile_lat: 32,
          tile_lon: -98,
          single_job_id: "cds-single-123",
          pressure_job_id: "cds-pressure-456",
          submitted_at: fresh_submit
        },
        overrides
      )

    {:ok, row} = %Era5CdsJob{} |> Era5CdsJob.changeset(attrs) |> Repo.insert()
    row
  end

  describe "perform/1 — row lifecycle" do
    test "returns :ok and does nothing when the era5_cds_jobs row no longer exists" do
      # Row was already processed/deleted by a previous poll run; snooze is
      # scheduled behind us in time; just no-op.
      Req.Test.stub(Era5Client, fn _ -> raise "CDS should not be contacted" end)

      missing_id = Ecto.UUID.generate()

      assert :ok =
               Era5PollWorker.perform(%Oban.Job{args: %{"era5_cds_job_id" => missing_id}})
    end
  end

  describe "perform/1 — still running" do
    test "returns {:snooze, seconds} and bumps poll_count when either CDS job is still running" do
      row = insert_cds_job()

      Req.Test.stub(Era5Client, fn conn ->
        assert conn.method == "GET"
        Req.Test.json(conn, %{"status" => "running"})
      end)

      assert {:snooze, snooze_s} =
               Era5PollWorker.perform(%Oban.Job{args: %{"era5_cds_job_id" => row.id}})

      assert snooze_s > 0

      reloaded = Repo.get!(Era5CdsJob, row.id)
      assert reloaded.poll_count == 1
      assert reloaded.last_polled_at
    end
  end

  describe "perform/1 — CDS job vanished (404)" do
    test "deletes the row, deletes the other CDS job, re-enqueues Era5SubmitWorker, and discards" do
      row = insert_cds_job()
      test_pid = self()

      Req.Test.stub(Era5Client, fn conn ->
        cond do
          conn.method == "GET" and String.contains?(conn.request_path, "cds-single-123") ->
            conn
            |> Plug.Conn.put_resp_content_type("application/json")
            |> Plug.Conn.resp(404, ~s({"detail":"job deleted","title":"job not found"}))

          conn.method == "GET" and String.contains?(conn.request_path, "cds-pressure-456") ->
            Req.Test.json(conn, %{"status" => "running"})

          conn.method == "DELETE" ->
            send(test_pid, {:delete, conn.request_path})
            Plug.Conn.resp(conn, 204, "")
        end
      end)

      # Run with manual Oban testing so the re-enqueued Era5SubmitWorker is
      # inserted into the queue but not executed inline — we only want to
      # assert that the row was deleted and the re-submit was scheduled.
      result =
        Oban.Testing.with_testing_mode(:manual, fn ->
          Era5PollWorker.perform(%Oban.Job{args: %{"era5_cds_job_id" => row.id}})
        end)

      assert {:discard, reason} = result
      assert reason =~ "deleted"
      refute Repo.get(Era5CdsJob, row.id)

      # The sibling CDS job gets cleaned up too so it doesn't linger on CDS.
      assert_received {:delete, "/api/retrieve/v1/jobs/cds-pressure-456"}

      # A fresh Era5SubmitWorker job is enqueued so the month gets re-fetched.
      assert_enqueued(
        worker: Era5SubmitWorker,
        args: %{year: 2014, month: 3, tile_lat: 32, tile_lon: -98}
      )
    end
  end

  describe "perform/1 — CDS job rejected (over-cap)" do
    test "deletes the row, cleans up the sibling CDS job, re-enqueues submit, and discards" do
      row = insert_cds_job()
      test_pid = self()

      Req.Test.stub(Era5Client, fn conn ->
        cond do
          conn.method == "GET" and String.contains?(conn.request_path, "cds-single-123") ->
            Req.Test.json(conn, %{
              "jobID" => "cds-single-123",
              "status" => "rejected",
              "metadata" => %{"origin" => "api"}
            })

          conn.method == "GET" and String.contains?(conn.request_path, "cds-pressure-456") ->
            Req.Test.json(conn, %{"status" => "running"})

          conn.method == "DELETE" ->
            send(test_pid, {:delete, conn.request_path})
            Plug.Conn.resp(conn, 204, "")
        end
      end)

      result =
        Oban.Testing.with_testing_mode(:manual, fn ->
          Era5PollWorker.perform(%Oban.Job{args: %{"era5_cds_job_id" => row.id}})
        end)

      assert {:discard, reason} = result
      assert reason =~ "rejected"
      refute Repo.get(Era5CdsJob, row.id)

      # Sibling CDS job is cleaned up so we don't burn queue slots waiting on
      # a request we've already abandoned.
      assert_received {:delete, "/api/retrieve/v1/jobs/cds-pressure-456"}

      # A fresh Era5SubmitWorker job is enqueued so the tile-month gets
      # re-submitted once the CDS cap has room.
      assert_enqueued(
        worker: Era5SubmitWorker,
        args: %{year: 2014, month: 3, tile_lat: 32, tile_lon: -98}
      )
    end
  end

  describe "perform/1 — stuck in CDS queue" do
    # A CDS job that's been in 'accepted' state for many hours is stuck in
    # the server's queue and unlikely to ever run. We track submitted_at
    # on era5_cds_jobs, so once the row ages past @stuck_after, poll
    # treats it as terminal and re-submits — same path as :not_found /
    # :rejected.
    #
    # Threshold is 8h (see @stuck_after_seconds in Era5PollWorker). We
    # observed the previous 18h threshold held a row polling for ~13h
    # without catching a stuck state while 0 profiles were being
    # ingested. 8h is a diagnostic compromise: short enough to recycle
    # stuck rows within a shift, still above the ~90 min pressure-level
    # normal completion time so healthy runs aren't interrupted.
    test "re-submits when submitted_at is older than 8h and at least one leg is still running" do
      stale_submit =
        DateTime.utc_now()
        |> DateTime.add(-9 * 3600, :second)
        |> DateTime.truncate(:second)

      row = insert_cds_job(%{submitted_at: stale_submit})
      test_pid = self()

      Req.Test.stub(Era5Client, fn conn ->
        cond do
          conn.method == "GET" ->
            Req.Test.json(conn, %{"status" => "accepted"})

          conn.method == "DELETE" ->
            send(test_pid, {:delete, conn.request_path})
            Plug.Conn.resp(conn, 204, "")
        end
      end)

      result =
        Oban.Testing.with_testing_mode(:manual, fn ->
          Era5PollWorker.perform(%Oban.Job{args: %{"era5_cds_job_id" => row.id}})
        end)

      assert {:discard, reason} = result
      assert reason =~ "stuck"
      refute Repo.get(Era5CdsJob, row.id)

      assert_enqueued(
        worker: Era5SubmitWorker,
        args: %{year: 2014, month: 3, tile_lat: 32, tile_lon: -98}
      )
    end

    test "does NOT re-submit a 6h-old row that's still running (under the 8h threshold)" do
      # Observed in prod: CDS pressure-level completes in ~90 min, so
      # anything under the 8h diagnostic threshold should keep snoozing,
      # not trigger a re-submit storm. The single-level leg is allowed
      # to keep running — only the combined age is stale, and 6h is
      # still well within the envelope.
      slowish_submit =
        DateTime.utc_now()
        |> DateTime.add(-6 * 3600, :second)
        |> DateTime.truncate(:second)

      row = insert_cds_job(%{submitted_at: slowish_submit})

      Req.Test.stub(Era5Client, fn conn ->
        Req.Test.json(conn, %{"status" => "running"})
      end)

      assert {:snooze, _} =
               Era5PollWorker.perform(%Oban.Job{args: %{"era5_cds_job_id" => row.id}})

      assert Repo.get(Era5CdsJob, row.id)
    end

    test "does NOT re-submit when submitted_at is recent even if running" do
      # A 30-minute-old row with both legs running is normal — snooze.
      fresh_submit =
        DateTime.utc_now()
        |> DateTime.add(-30 * 60, :second)
        |> DateTime.truncate(:second)

      row = insert_cds_job(%{submitted_at: fresh_submit})

      Req.Test.stub(Era5Client, fn conn ->
        Req.Test.json(conn, %{"status" => "running"})
      end)

      assert {:snooze, _} =
               Era5PollWorker.perform(%Oban.Job{args: %{"era5_cds_job_id" => row.id}})

      assert Repo.get(Era5CdsJob, row.id)
    end
  end

  describe "perform/1 — transient CDS HTTP error" do
    # Observed in prod 2026-04-15: a brief CDS network blip returned HTTP
    # 5xx on check_status. The old {:error, _} branches consumed attempts
    # and max_attempts=10 burned out in seconds, so 13 rows became
    # orphaned (discarded with no cleanup, no active poll worker). The
    # fix: treat HTTP errors as transient — snooze without counting an
    # attempt. Terminal states (:failed, :rejected, :not_found) still
    # drive the fail/resubmit paths.
    test "snoozes and keeps the row when single-level check_status returns a transient HTTP error" do
      row = insert_cds_job()

      Req.Test.stub(Era5Client, fn conn ->
        cond do
          conn.method == "GET" and String.contains?(conn.request_path, "cds-single-123") ->
            conn
            |> Plug.Conn.put_resp_content_type("application/json")
            |> Plug.Conn.resp(503, ~s({"error":"service unavailable"}))

          conn.method == "GET" and String.contains?(conn.request_path, "cds-pressure-456") ->
            Req.Test.json(conn, %{"status" => "running"})
        end
      end)

      assert {:snooze, snooze_s} =
               Era5PollWorker.perform(%Oban.Job{args: %{"era5_cds_job_id" => row.id}})

      assert snooze_s > 0
      assert Repo.get(Era5CdsJob, row.id)
    end

    test "snoozes and keeps the row when pressure-level check_status returns a transient HTTP error" do
      row = insert_cds_job()

      Req.Test.stub(Era5Client, fn conn ->
        cond do
          conn.method == "GET" and String.contains?(conn.request_path, "cds-single-123") ->
            Req.Test.json(conn, %{"status" => "running"})

          conn.method == "GET" and String.contains?(conn.request_path, "cds-pressure-456") ->
            conn
            |> Plug.Conn.put_resp_content_type("application/json")
            |> Plug.Conn.resp(502, ~s({"error":"bad gateway"}))
        end
      end)

      assert {:snooze, snooze_s} =
               Era5PollWorker.perform(%Oban.Job{args: %{"era5_cds_job_id" => row.id}})

      assert snooze_s > 0
      assert Repo.get(Era5CdsJob, row.id)
    end
  end

  describe "perform/1 — failure" do
    test "returns {:error, _}, deletes the row, and deletes both CDS jobs when a leg fails" do
      row = insert_cds_job()
      test_pid = self()

      Req.Test.stub(Era5Client, fn conn ->
        cond do
          conn.method == "GET" and String.contains?(conn.request_path, "cds-single-123") ->
            Req.Test.json(conn, %{"status" => "failed", "message" => "bad input"})

          conn.method == "GET" and String.contains?(conn.request_path, "cds-pressure-456") ->
            Req.Test.json(conn, %{"status" => "running"})

          conn.method == "DELETE" ->
            send(test_pid, {:delete, conn.request_path})
            Plug.Conn.resp(conn, 204, "")
        end
      end)

      assert {:error, reason} =
               Era5PollWorker.perform(%Oban.Job{args: %{"era5_cds_job_id" => row.id}})

      assert reason =~ "bad input"
      refute Repo.get(Era5CdsJob, row.id)

      # Both CDS jobs are deleted to free server-side quota.
      assert_received {:delete, "/api/retrieve/v1/jobs/cds-single-123"}
      assert_received {:delete, "/api/retrieve/v1/jobs/cds-pressure-456"}
    end
  end
end