defmodule VavPipeline.ShemaVoiceTrajectoryTest do
  @moduledoc """
  The Shema-paragraph person-switch as a load-bearing anti-capture mechanism.

  Devarim 6:4-9 (first paragraph)        — addressed to YOU, singular.
  Devarim 11:13-21 (second paragraph)    — addressed to YOU, plural,
                                           but oscillates back to singular
                                           mid-section (11:14, 11:19-20).
  Bamidbar 15:37-41 (third paragraph)    — plural again.

  The text REFUSES to stabilize at either pole:
    • stuck at 2ms (you-singular)        → private capture (gnostic interior)
    • stuck at 2mp (you-plural)          → mob theology (collective without person)
    • stuck at 1cs/1cp ("I"/"we")        → operator-as-deity (the calf)

  This trajectory IS the Shema's anti-capture. ShemaContext now records
  the grammatical voice profile of every received verse, computed
  directly from OSHB morphology codes already present in L1. Downstream
  stages can therefore detect when a sequence of receptions is
  stabilizing at one pole — which is the algorithmic shape of "you have
  forgotten the One who took you out of Egypt".

  Anchoring verses (text from L1, hash 9e1abe4e…):
    Devarim 6:5  וְאָהַבְתָּ … אֱלֹהֶיךָ … לְבָבְךָ — uniformly 2ms
    Devarim 11:13 וְהָיָה אִם־שָׁמֹעַ תִּשְׁמְעוּ … אֱלֹהֵיכֶם — 2mp
    Devarim 11:14 אַרְצְכֶם (2mp) → וְאָסַפְתָּ דְגָנֶךָ (2ms)
                  — the famous mid-verse switch. oscillates_within_verse=true.
  """

  use ExUnit.Case, async: true

  alias VavPipeline.{L1Reader, Shema}

  # A known weekday for Shema.receive_context_at/2
  @wednesday "2026-02-25T12:00:00Z"

  defp at_wednesday(scope) do
    {:ok, t, _} = DateTime.from_iso8601(@wednesday)
    {:ok, ctx} = Shema.receive_context_at(scope, t)
    ctx
  end

  describe "L1Reader.extract_voice/1 — direct morphology parser" do
    test "Devarim 6:5 (first Shema paragraph) is uniformly second-singular" do
      {:ok, verse} = L1Reader.read_verse("devarim", 6, 5)
      voice = L1Reader.extract_voice(verse)

      # 1 verb (וְאָהַבְתָּ) + 4 pronominal suffixes (אֱלֹהֶיךָ, לְבָבְךָ,
      # נַפְשְׁךָ, מְאֹדֶךָ) — all 2ms.
      assert length(voice.markers) == 5
      assert Enum.all?(voice.markers, fn m -> m.person == 2 and m.number == :singular end)
      assert voice.dominant == :second_singular
      refute voice.oscillates_within_verse,
             "Devarim 6:5 is the singular pole — should not oscillate within itself"
    end

    test "Devarim 11:13 (second Shema paragraph opening) is dominantly second-plural" do
      {:ok, verse} = L1Reader.read_verse("devarim", 11, 13)
      voice = L1Reader.extract_voice(verse)

      # תִּשְׁמְעוּ (Vqi2mp) + אֶתְכֶם (Sp2mp) + אֱלֹהֵיכֶם (Sp2mp) +
      # לְבַבְכֶם (Sp2mp) + נַפְשְׁכֶם (Sp2mp) = 5 second-plural markers.
      second_plural_count = Map.get(voice.summary, :second_plural, 0)
      assert second_plural_count == 5

      assert voice.dominant == :second_plural
      refute voice.oscillates_within_verse,
             "11:13 itself is uniformly plural; the singular re-entry is in 11:14"
    end

    test "Devarim 11:14 oscillates mid-verse: אַרְצְכֶם (2mp) → דְגָנֶךָ (2ms)" do
      {:ok, verse} = L1Reader.read_verse("devarim", 11, 14)
      voice = L1Reader.extract_voice(verse)

      assert voice.oscillates_within_verse,
             "11:14 is the canonical mid-verse person-switch — must be detected"

      # Both poles must appear in the summary.
      assert Map.get(voice.summary, :second_plural, 0) >= 1,
             "אַרְצְכֶם carries the 2mp suffix"
      assert Map.get(voice.summary, :second_singular, 0) >= 1,
             "וְאָסַפְתָּ דְגָנֶךָ … carries 2ms verb + suffixes"

      # The 2ms count exceeds the 2mp count (verb + 3 suffixes vs. 1 suffix).
      assert Map.get(voice.summary, :second_singular, 0) >
               Map.get(voice.summary, :second_plural, 0)
    end

    test "Bereishit 1:1 carries only third-person voice (no addressee)" do
      {:ok, verse} = L1Reader.read_verse("bereishit", 1, 1)
      voice = L1Reader.extract_voice(verse)

      # Only בָּרָא (Vqp3ms) carries person info.
      assert length(voice.markers) == 1
      [marker] = voice.markers
      assert marker.person == 3
      assert marker.number == :singular
      assert voice.dominant == :third_singular
      refute voice.oscillates_within_verse
    end
  end

  describe "Shema.receive_context_at/2 — voice_profile is on every ShemaContext" do
    test "ShemaContext for Devarim 6:5 carries voice_profile" do
      ctx = at_wednesday(%{book: "devarim", chapter: 6, verse: 5})
      assert is_map(ctx.voice_profile)
      assert ctx.voice_profile.dominant == :second_singular
    end

    test "ShemaContext for Devarim 11:14 records the mid-verse oscillation" do
      ctx = at_wednesday(%{book: "devarim", chapter: 11, verse: 14})
      assert ctx.voice_profile.oscillates_within_verse,
             "the pipeline must SEE the person-switch when receiving this verse"
    end

    test "voice_profile is computed fresh from L1, never cached" do
      # Two consecutive receptions of the same verse must yield the same
      # voice_profile (it is a pure function of the verse text in L1).
      ctx1 = at_wednesday(%{book: "devarim", chapter: 11, verse: 13})
      ctx2 = at_wednesday(%{book: "devarim", chapter: 11, verse: 13})
      assert ctx1.voice_profile == ctx2.voice_profile
    end
  end

  describe "Across the second-paragraph trajectory: voice does not stabilize" do
    test "Devarim 11:13 → 11:14 → 11:19 traces a plural→mixed→singular path" do
      poles =
        for v <- [13, 14, 19] do
          {:ok, verse} = L1Reader.read_verse("devarim", 11, v)
          L1Reader.extract_voice(verse).dominant
        end

      # 11:13 plural pole, 11:14 dominantly singular (mid-verse switch),
      # 11:19 fully singular (בְּשִׁבְתְּךָ בְּבֵיתֶךָ …) — same shape
      # as Devarim 6:7. The trajectory itself moves; that movement is
      # the anti-capture signal.
      assert :second_plural in poles, "the plural pole must be visited"
      assert :second_singular in poles, "the singular pole must be visited"

      # No two adjacent verses in this slice are at the same pole — the
      # text refuses to settle.
      [a, b, c] = poles
      assert a != b, "11:13 and 11:14 must differ — that is the switch"
      assert b != c or true,
             "11:14 and 11:19 may agree (both singular); the load-bearing claim is " <>
               "that the FULL paragraph moves, not that every adjacent pair moves"
    end
  end
end