prop/test/microwaveprop/space_weather/swpc_client_test.exs

defmodule Microwaveprop.SpaceWeather.SwpcClientTest do
  use ExUnit.Case, async: true
  use ExUnitProperties

  alias Microwaveprop.SpaceWeather.SwpcClient

  describe "parse_kp/1" do
    test "decodes the SWPC planetary_k_index_1m fixture" do
      body = File.read!("test/fixtures/swpc/kp_sample.json")

      assert {:ok, rows} = SwpcClient.parse_kp(body)
      assert length(rows) == 10

      first = hd(rows)
      assert first.valid_time == ~U[2026-04-15 13:49:00Z]
      assert first.kp_index == 0
      assert_in_delta first.estimated_kp, 0.33, 0.001
    end

    test "returns {:error, _} for malformed bodies" do
      assert {:error, _} = SwpcClient.parse_kp("not json")
      assert {:error, _} = SwpcClient.parse_kp(~s({"not": "an array"}))
    end
  end

  describe "fetch_xrays/0 upstream truncation" do
    # SWPC occasionally returns a truncated JSON body (TCP reset mid-stream).
    # Req's auto-decoder raises a Jason.DecodeError carrying the entire
    # raw body in :data — historically that dumped hundreds of KB into
    # our Logger. The error should be returned, but formatted short.
    test "returns {:error, reason} without dumping the full truncated body" do
      big_body = "[" <> String.duplicate(~s({"time_tag":"2026-04-20T21:35:00Z","energy":"0.1-0.8nm","flux":1.0},), 20_000)
      # Truncate — no closing bracket.
      truncated = big_body

      Req.Test.stub(SwpcClient, fn conn ->
        conn
        |> Plug.Conn.put_resp_content_type("application/json")
        |> Plug.Conn.send_resp(200, truncated)
      end)

      assert {:error, reason} = SwpcClient.fetch_xrays()
      assert is_binary(reason)
      # Upper-bound the log-noise blast radius.
      assert byte_size(reason) < 500
      # Still descriptive.
      assert reason =~ ~r/(decode|JSON|truncated|Jason)/i
    end
  end

  describe "parse_f107/1" do
    test "decodes the SWPC f107_cm_flux fixture" do
      body = File.read!("test/fixtures/swpc/f107_sample.json")

      assert {:ok, rows} = SwpcClient.parse_f107(body)
      assert length(rows) == 10

      first = hd(rows)
      assert first.valid_time == ~U[2026-04-15 17:00:00Z]
      assert first.frequency_mhz == 2800
      assert first.flux_sfu == 112.0
      assert first.reporting_schedule == "Morning"
    end

    test "keeps nullable historical stats as nil when absent" do
      body = File.read!("test/fixtures/swpc/f107_sample.json")
      {:ok, [first | _]} = SwpcClient.parse_f107(body)
      assert first.ninety_day_mean == nil
    end
  end

  describe "parse_xrays/1" do
    test "decodes the GOES xrays-1-day fixture, keeping the 0.1-0.8nm band only" do
      body = File.read!("test/fixtures/swpc/xrays_sample.json")

      assert {:ok, rows} = SwpcClient.parse_xrays(body)
      # Fixture has 12 records (6 timestamps × 2 bands). We keep the
      # long-wavelength band (0.1-0.8nm) which is the standard SWF /
      # D-layer absorption proxy.
      assert length(rows) == 6
      assert Enum.all?(rows, fn r -> r.energy_band == "0.1-0.8nm" end)

      first = hd(rows)
      assert first.valid_time == ~U[2026-04-14 19:49:00Z]
      assert first.satellite == 18
      assert_in_delta first.flux_wm2, 3.523e-07, 1.0e-09
    end

    test "filters out rows whose energy band isn't the long-wavelength one" do
      body =
        Jason.encode!([
          %{
            "time_tag" => "2026-04-14T19:49:00Z",
            "satellite" => 18,
            "flux" => 1.0e-7,
            "energy" => "0.05-0.4nm"
          },
          %{
            "time_tag" => "2026-04-14T19:49:00Z",
            "satellite" => 18,
            "flux" => 3.523e-7,
            "energy" => "0.1-0.8nm"
          }
        ])

      assert {:ok, [row]} = SwpcClient.parse_xrays(body)
      assert row.energy_band == "0.1-0.8nm"
    end

    test "flags electron_contaminated when the (misspelled upstream) key is truthy" do
      body =
        Jason.encode!([
          %{
            "time_tag" => "2026-04-14T19:49:00Z",
            "satellite" => 18,
            "flux" => 3.5e-7,
            "energy" => "0.1-0.8nm",
            "electron_contaminaton" => true
          }
        ])

      assert {:ok, [row]} = SwpcClient.parse_xrays(body)
      assert row.electron_contaminated == true
    end

    test "silently drops rows whose time_tag won't parse" do
      body =
        Jason.encode!([
          %{
            "time_tag" => "not-a-timestamp",
            "satellite" => 18,
            "flux" => 3.5e-7,
            "energy" => "0.1-0.8nm"
          },
          %{
            "time_tag" => "2026-04-14T19:49:00Z",
            "satellite" => 18,
            "flux" => 3.5e-7,
            "energy" => "0.1-0.8nm"
          }
        ])

      assert {:ok, [row]} = SwpcClient.parse_xrays(body)
      assert row.valid_time == ~U[2026-04-14 19:49:00Z]
    end
  end

  describe "parse_* shared helpers" do
    test "parse_kp drops rows whose time_tag is unparseable" do
      body =
        Jason.encode!([
          %{"time_tag" => "garbage", "kp_index" => 1},
          %{"time_tag" => "2026-04-15T13:49:00", "kp_index" => 3, "estimated_kp" => 3.67}
        ])

      assert {:ok, [row]} = SwpcClient.parse_kp(body)
      assert row.kp_index == 3
      assert row.valid_time == ~U[2026-04-15 13:49:00Z]
    end

    test "parse_kp tolerates integer and string numerics for kp_index" do
      body =
        Jason.encode!([
          %{"time_tag" => "2026-04-15T13:49:00", "kp_index" => "4", "estimated_kp" => "4.33"},
          %{"time_tag" => "2026-04-15T13:50:00", "kp_index" => 5, "estimated_kp" => 5.0}
        ])

      assert {:ok, rows} = SwpcClient.parse_kp(body)
      assert Enum.map(rows, & &1.kp_index) == [4, 5]
      assert Enum.map(rows, & &1.estimated_kp) == [4.33, 5.0]
    end

    test "parse_f107 carries frequency, flux, schedule, and ninety_day_mean" do
      body =
        Jason.encode!([
          %{
            "time_tag" => "2026-04-15T17:00:00",
            "frequency" => 2800,
            "flux" => 142.4,
            "reporting_schedule" => "Morning",
            "ninety_day_mean" => 150.0
          }
        ])

      assert {:ok, [row]} = SwpcClient.parse_f107(body)
      assert row.frequency_mhz == 2800
      assert row.flux_sfu == 142.4
      assert row.reporting_schedule == "Morning"
      assert row.ninety_day_mean == 150.0
    end

    test "parse_* accept an already-decoded list body (Req auto-decode case)" do
      list = [
        %{"time_tag" => "2026-04-15T13:49:00", "kp_index" => 2, "estimated_kp" => 2.33}
      ]

      # parse_kp is the representative here — the shared decode_array
      # helper delegates the list path for every product.
      assert {:ok, [row]} = SwpcClient.parse_kp(list)
      assert row.kp_index == 2
    end

    test "parse_* return {:error, :not_a_list} for JSON objects" do
      assert {:error, :not_a_list} = SwpcClient.parse_kp(~s({"not":"list"}))
      assert {:error, :not_a_list} = SwpcClient.parse_f107(~s({"not":"list"}))
      assert {:error, :not_a_list} = SwpcClient.parse_xrays(~s({"not":"list"}))
    end

    test "parse_kp returns {:ok, []} for an empty JSON array" do
      assert {:ok, []} = SwpcClient.parse_kp("[]")
    end

    test "parse_f107 returns {:ok, []} for an empty JSON array" do
      assert {:ok, []} = SwpcClient.parse_f107("[]")
    end

    test "parse_xrays returns {:ok, []} for an empty JSON array" do
      assert {:ok, []} = SwpcClient.parse_xrays("[]")
    end

    test "parse_* reject bare non-list non-string inputs" do
      assert {:error, :not_a_list} = SwpcClient.parse_kp(nil)
      assert {:error, :not_a_list} = SwpcClient.parse_kp(123)
      assert {:error, :not_a_list} = SwpcClient.parse_f107(:an_atom)
    end
  end

  describe "parse_* totality property" do
    property "parse_kp/1 never raises on arbitrary printable strings" do
      # Malformed JSON must surface as a tagged {:ok, _} / {:error, _}
      # tuple — the caller logs and moves on. A crash would kill the
      # worker and blow past its retry budget.
      check all(body <- string(:printable, max_length: 120)) do
        result = SwpcClient.parse_kp(body)
        assert match?({:ok, _}, result) or match?({:error, _}, result)
      end
    end

    property "parse_xrays/1 never raises on arbitrary printable strings" do
      check all(body <- string(:printable, max_length: 120)) do
        result = SwpcClient.parse_xrays(body)
        assert match?({:ok, _}, result) or match?({:error, _}, result)
      end
    end
  end

  describe "fetch_kp/0 HTTP errors" do
    test "non-200 surfaces as {:error, 'SWPC HTTP ...'}" do
      Req.Test.stub(SwpcClient, fn conn ->
        conn
        |> Plug.Conn.put_resp_content_type("text/plain")
        |> Plug.Conn.send_resp(503, "unavailable")
      end)

      assert {:error, reason} = SwpcClient.fetch_kp()
      assert reason =~ "SWPC HTTP 503"
    end

    test "transport timeout surfaces as {:error, 'SWPC request failed: ...'}" do
      Req.Test.stub(SwpcClient, fn conn ->
        Req.Test.transport_error(conn, :timeout)
      end)

      assert {:error, reason} = SwpcClient.fetch_kp()
      assert reason =~ "SWPC request failed"
    end
  end

  describe "fetch_f107/0 HTTP errors" do
    test "404 on the f107 endpoint is surfaced verbatim" do
      Req.Test.stub(SwpcClient, fn conn ->
        conn
        |> Plug.Conn.put_resp_content_type("text/plain")
        |> Plug.Conn.send_resp(404, "gone")
      end)

      assert {:error, reason} = SwpcClient.fetch_f107()
      assert reason =~ "SWPC HTTP 404"
    end
  end
end