import request from "supertest";
import { afterEach, describe, expect, it, vi } from "vitest";

const FLAG_KEYS = [
  "FEATURE_ASSISTANT_INVESTIGATION_STATE_V1",
  "FEATURE_ASSISTANT_STATE_FOLLOWUP_BINDING_V1",
  "FEATURE_ASSISTANT_CONTRACTS_V11",
  "FEATURE_ASSISTANT_PROBLEM_UNITS_V1",
  "FEATURE_ASSISTANT_PROBLEM_UNIT_CONTINUITY_V1",
  "FEATURE_ASSISTANT_ANSWER_POLICY_V11",
  "FEATURE_ASSISTANT_PROBLEM_CENTRIC_ANSWER_V1"
] as const;

const ORIGINAL_FLAGS: Record<string, string | undefined> = Object.fromEntries(
  FLAG_KEYS.map((key) => [key, process.env[key]])
);

function restoreFlags(): void {
  for (const key of FLAG_KEYS) {
    const original = ORIGINAL_FLAGS[key];
    if (original === undefined) {
      delete process.env[key];
    } else {
      process.env[key] = original;
    }
  }
}

async function createAppWithFlags(flags: {
  state: "0" | "1";
  binding: "0" | "1";
  contracts?: "0" | "1";
  problemUnits?: "0" | "1";
  continuity?: "0" | "1";
  answerPolicy?: "0" | "1";
  problemCentric?: "0" | "1";
}) {
  process.env.FEATURE_ASSISTANT_INVESTIGATION_STATE_V1 = flags.state;
  process.env.FEATURE_ASSISTANT_STATE_FOLLOWUP_BINDING_V1 = flags.binding;
  process.env.FEATURE_ASSISTANT_CONTRACTS_V11 = flags.contracts ?? "1";
  process.env.FEATURE_ASSISTANT_PROBLEM_UNITS_V1 = flags.problemUnits ?? "0";
  process.env.FEATURE_ASSISTANT_PROBLEM_UNIT_CONTINUITY_V1 = flags.continuity ?? "0";
  process.env.FEATURE_ASSISTANT_ANSWER_POLICY_V11 = flags.answerPolicy ?? "0";
  process.env.FEATURE_ASSISTANT_PROBLEM_CENTRIC_ANSWER_V1 = flags.problemCentric ?? "0";
  vi.resetModules();
  const { createApp } = await import("../src/server");
  return createApp();
}

describe.sequential("assistant follow-up state binding", () => {
  afterEach(() => {
    restoreFlags();
    vi.resetModules();
  });

  it("applies investigation_state binding in follow-up flow when flags are ON", async () => {
    const app = await createAppWithFlags({
      state: "1",
      binding: "1"
    });
    const sessionId = `asst-wave2-on-${Date.now()}`;

    const first = await request(app).post("/api/assistant/message").send({
      session_id: sessionId,
      useMock: true,
      promptVersion: "normalizer_v2_0_2",
      user_message: "Разложи цепочку документов по контрагентам."
    });

    expect(first.status).toBe(200);
    expect(first.body.debug?.followup_state_usage).toBeUndefined();
    expect(first.body.debug?.investigation_state_snapshot?.turn_index).toBe(1);

    const second = await request(app).post("/api/assistant/message").send({
      session_id: sessionId,
      useMock: true,
      promptVersion: "normalizer_v2_0_2",
      user_message: "И по периоду 2020-06."
    });

    expect(second.status).toBe(200);
    expect(second.body.debug?.followup_state_usage?.applied).toBe(true);
    expect(second.body.debug?.followup_state_usage?.context_patch?.business_context_from_state).toBe(true);
    expect(second.body.debug?.followup_state_usage?.state_turn_index).toBe(1);
    expect(
      (second.body.debug?.routes ?? []).some((item: { route?: string }) => item.route && item.route !== "no_route")
    ).toBe(true);
    expect(second.body.debug?.investigation_state_snapshot?.turn_index).toBe(2);
  });

  it("does not apply follow-up binding when binding flag is OFF", async () => {
    const app = await createAppWithFlags({
      state: "1",
      binding: "0"
    });
    const sessionId = `asst-wave2-off-${Date.now()}`;

    const first = await request(app).post("/api/assistant/message").send({
      session_id: sessionId,
      useMock: true,
      promptVersion: "normalizer_v2_0_2",
      user_message: "Разложи цепочку документов по контрагентам."
    });
    expect(first.status).toBe(200);

    const second = await request(app).post("/api/assistant/message").send({
      session_id: sessionId,
      useMock: true,
      promptVersion: "normalizer_v2_0_2",
      user_message: "И по периоду 2020-06."
    });

    expect(second.status).toBe(200);
    expect(second.body.debug?.followup_state_usage).toBeUndefined();
    expect((second.body.debug?.routes ?? []).every((item: { route?: string }) => item.route === "no_route")).toBe(true);
  });

  it("keeps legacy-like behavior when investigation state flag is OFF", async () => {
    const app = await createAppWithFlags({
      state: "0",
      binding: "1"
    });

    const response = await request(app).post("/api/assistant/message").send({
      useMock: true,
      promptVersion: "normalizer_v2_0_2",
      user_message: "И по периоду 2020-06."
    });

    expect(response.status).toBe(200);
    expect(response.body.debug?.investigation_state_snapshot).toBeNull();
    expect(response.body.debug?.followup_state_usage).toBeUndefined();
  });

  it("applies problem continuity hints only when continuity flag is ON and follow-up has no strong new anchors", async () => {
    const app = await createAppWithFlags({
      state: "1",
      binding: "1",
      problemUnits: "1",
      continuity: "1"
    });
    const sessionId = `asst-wave4-problem-continuity-${Date.now()}`;

    const first = await request(app).post("/api/assistant/message").send({
      session_id: sessionId,
      useMock: true,
      promptVersion: "normalizer_v2_0_2",
      user_message: "Разложи цепочку документов и оплат по контрагентам за 2020-06, где разрыв механизма закрытия."
    });
    expect(first.status).toBe(200);
    expect(first.body.debug?.investigation_state_snapshot?.problem_unit_state).toBeTruthy();

    const second = await request(app).post("/api/assistant/message").send({
      session_id: sessionId,
      useMock: true,
      promptVersion: "normalizer_v2_0_2",
      user_message: "И по тому же разрыву добавь уточнение."
    });

    expect(second.status).toBe(200);
    expect(second.body.debug?.followup_state_usage?.applied).toBe(true);
    expect(second.body.debug?.followup_state_usage?.context_patch?.problem_continuity_available).toBe(true);
    expect(second.body.debug?.followup_state_usage?.context_patch?.problem_continuity_applied).toBe(true);
    expect(second.body.debug?.followup_state_usage?.context_patch?.strong_new_anchor_detected).toBe(false);
  });

  it("does not apply follow-up continuity when user gives strong new anchors", async () => {
    const app = await createAppWithFlags({
      state: "1",
      binding: "1",
      problemUnits: "1",
      continuity: "1"
    });
    const sessionId = `asst-wave4-strong-anchor-${Date.now()}`;

    const first = await request(app).post("/api/assistant/message").send({
      session_id: sessionId,
      useMock: true,
      promptVersion: "normalizer_v2_0_2",
      user_message: "Разбери хвосты по счету 60 за 2020-06 и покажи проблемные цепочки."
    });
    expect(first.status).toBe(200);
    expect(first.body.debug?.investigation_state_snapshot?.turn_index).toBe(1);

    const second = await request(app).post("/api/assistant/message").send({
      session_id: sessionId,
      useMock: true,
      promptVersion: "normalizer_v2_0_2",
      user_message: "И отдельно по счету 97 за 2020-07."
    });

    expect(second.status).toBe(200);
    expect(second.body.debug?.followup_state_usage).toBeUndefined();
    expect(second.body.debug?.investigation_state_snapshot?.turn_index).toBe(2);
  });

  it("isolates scope for independent cross-domain turn and does not carry stale period/domain", async () => {
    const app = await createAppWithFlags({
      state: "1",
      binding: "1",
      problemUnits: "1",
      continuity: "1",
      answerPolicy: "1",
      problemCentric: "1"
    });
    const sessionId = `asst-wave17-scope-isolation-${Date.now()}`;

    const first = await request(app).post("/api/assistant/message").send({
      session_id: sessionId,
      useMock: true,
      promptVersion: "normalizer_v2_0_2",
      user_message: "Проверь хвосты по счету 60.01 за 2020-06 и почему не закрылся долг."
    });
    expect(first.status).toBe(200);
    expect(first.body.debug?.investigation_state_snapshot?.question_scope_id).toContain("d:settlements_60_62");
    expect(first.body.debug?.investigation_state_snapshot?.scope_origin).toBe("explicit_from_message");

    const second = await request(app).post("/api/assistant/message").send({
      session_id: sessionId,
      useMock: true,
      promptVersion: "normalizer_v2_0_2",
      user_message: "Проверь НДС по счету-фактуре: где разрыв в цепочке документ -> регистр -> книга?"
    });

    expect(second.status).toBe(200);
    expect(second.body.debug?.followup_state_usage).toBeUndefined();
    expect(second.body.debug?.investigation_state_snapshot?.scope_origin).toBe("explicit_from_message");
    expect(String(second.body.debug?.investigation_state_snapshot?.question_scope_id ?? "")).toContain(
      "d:vat_document_register_book"
    );
    expect(second.body.debug?.investigation_state_snapshot?.focus?.period).not.toBe("2020-06");
    expect(String(second.body.debug?.investigation_state_snapshot?.focus?.domain ?? "")).not.toContain("settlements_60_62");
    expect(second.body.debug?.investigation_state_snapshot?.followup_context?.question_scope_id).toBeTruthy();
    expect(second.body.debug?.investigation_state_snapshot?.followup_context?.scope_origin).toBe("explicit_from_message");
  });

  it("rebinds follow-up domain away from settlements on fixed-asset amortization query", async () => {
    const app = await createAppWithFlags({
      state: "1",
      binding: "1",
      problemUnits: "1",
      continuity: "1",
      answerPolicy: "1",
      problemCentric: "1"
    });
    const sessionId = `asst-wave16-fa-domain-${Date.now()}`;

    const first = await request(app).post("/api/assistant/message").send({
      session_id: sessionId,
      useMock: true,
      promptVersion: "normalizer_v2_0_2",
      user_message: "Почему деньги ушли, а долг по 60.01/62.02 остался?"
    });
    expect(first.status).toBe(200);
    expect(first.body.debug?.investigation_state_snapshot?.followup_context?.active_domain).toBe("settlements_60_62");

    const second = await request(app).post("/api/assistant/message").send({
      session_id: sessionId,
      useMock: true,
      promptVersion: "normalizer_v2_0_2",
      user_message:
        "Полно ли начислена амортизация по объектам ОС за июль? Проверь по 01/02, нет ли пропущенных объектов."
    });

    expect(second.status).toBe(200);
    const activeDomain = String(second.body.debug?.investigation_state_snapshot?.followup_context?.active_domain ?? "");
    expect(activeDomain).not.toBe("settlements_60_62");
    expect(activeDomain).toMatch(/fixed_asset_amortization|month_close_costs_20_44|no_route|hybrid_store_plus_live|fixed_asset/i);

    const settlementActions = second.body.debug?.investigation_state_snapshot?.followup_context?.settlement_next_actions;
    expect(Array.isArray(settlementActions) ? settlementActions.length : 0).toBe(0);
  });

  it("keeps UTF-8 follow-up period refinement in-scope with soft continuity hints", async () => {
    const app = await createAppWithFlags({
      state: "1",
      binding: "1",
      problemUnits: "1",
      continuity: "1",
      answerPolicy: "1",
      problemCentric: "1"
    });

    const first = await request(app).post("/api/assistant/message").send({
      useMock: true,
      promptVersion: "normalizer_v2_0_2",
      user_message: "Посмотри, пожалуйста, где по поставщикам сейчас хвосты уже похожи именно на проблему, а не просто на шум."
    });

    expect(first.status).toBe(200);
    expect(first.body.reply_type).not.toBe("out_of_scope");

    const second = await request(app).post("/api/assistant/message").send({
      session_id: first.body.session_id,
      useMock: true,
      promptVersion: "normalizer_v2_0_2",
      user_message: "А если только за июнь 2020 смотреть, по кому это сильнее всего видно и что из этого реально может мешать закрытию?"
    });

    expect(second.status).toBe(200);
    expect(second.body.reply_type).not.toBe("out_of_scope");
    expect(second.body.debug?.followup_state_usage?.applied).toBe(true);
    expect(typeof second.body.debug?.followup_state_usage?.context_patch?.problem_continuity_applied).toBe("boolean");
    expect(second.body.debug?.followup_state_usage?.context_patch?.strong_new_anchor_detected).toBe(false);
    expect(
      (second.body.debug?.routes ?? []).some((item: { route?: string }) => item.route && item.route !== "no_route")
    ).toBe(true);

    const third = await request(app).post("/api/assistant/message").send({
      useMock: true,
      promptVersion: "normalizer_v2_0_2",
      user_message: "Проверь, пожалуйста, по 60-му счёту за июнь 2020, где есть самый явный проблемный участок по расчётам с поставщиками."
    });

    expect(third.status).toBe(200);
    expect(third.body.reply_type).not.toBe("out_of_scope");
  });
});