/**
 * capabilityRouter.test.ts — Unit test S38 Capability Router
 *
 * Copertura (12 test):
 *  1. route: restituisce gemini per reasoning_depth="high" (score massimo)
 *  2. route: restituisce groq per speed=true (velocità 10/10)
 *  3. route: provider con vision=false escluso (score basso) quando req.vision=true
 *  4. route: provider senza tool calling penalizzato quando requires_tools=true
 *  5. route: prefer_free=true favorisce provider gratuiti
 *  6. route: long_context favorisce provider con max_context>=100k
 *  7. route: ritorna null se nessun provider disponibile
 *  8. route: ignora provider non disponibili (DI isAvailable=false)
 *  9. rankAll: ordina tutti i candidati per score decrescente
 * 10. scoreProfile: score > 0 per profilo compatibile con request
 * 11. scoreProfile: score molto negativo per vision req su provider senza vision
 * 12. getProfile / getAllProfiles: dati statici corretti
 *
 * DI pattern: _setTestDeps / _resetDeps — zero vi.mock su moduli ESM
 * Modulo puro: nessun side-effect, nessuna dipendenza da browser API
 *
 * SESSIONE: S38 — Capability Router
 * S342: aggiornato 12b per includere cerebras (8° provider, aggiunto in S325)
 */

import { describe, it, expect, beforeEach, afterEach } from "vitest";
import {
  route,
  rankAll,
  scoreProfile,
  getProfile,
  getAllProfiles,
  buildReason,
  CAPABILITY_PROFILES,
  _setTestDeps,
  _resetDeps,
} from "@/lib/capabilityRouter";

// ─── Setup / Teardown ─────────────────────────────────────────────────────────

beforeEach(() => {
  // Per default tutti i provider disponibili
  _setTestDeps({ isAvailable: () => true });
});

afterEach(() => {
  _resetDeps();
});

// ─── route ────────────────────────────────────────────────────────────────────

describe("route", () => {
  it("1. reasoning_depth=high → gemini o openai (reasoning_score >= 9)", () => {
    const result = route({ reasoning_depth: "high" });
    expect(result).not.toBeNull();
    expect(result!.profile.reasoning_score).toBeGreaterThanOrEqual(9);
    expect(["gemini", "openai"]).toContain(result!.provider);
  });

  it("2. speed=true → groq (speed_score 10/10)", () => {
    const result = route({ speed: true });
    expect(result).not.toBeNull();
    expect(result!.provider).toBe("groq");
    expect(result!.profile.speed_score).toBe(10);
  });

  it("3. vision=true → provider con vision:true (gemini, openai, openrouter)", () => {
    const result = route({ vision: true });
    expect(result).not.toBeNull();
    expect(result!.profile.vision).toBe(true);
    expect(["gemini", "openai", "openrouter"]).toContain(result!.provider);
  });

  it("4. requires_tools=true → provider con tools:true", () => {
    const result = route({ requires_tools: true });
    expect(result).not.toBeNull();
    expect(result!.profile.tools).toBe(true);
  });

  it("5. prefer_free=true → provider con free:true", () => {
    const result = route({ prefer_free: true });
    expect(result).not.toBeNull();
    expect(result!.profile.free).toBe(true);
  });

  it("6. long_context=true → provider con max_context >= 100k", () => {
    const result = route({ long_context: true });
    expect(result).not.toBeNull();
    expect(result!.profile.max_context).toBeGreaterThanOrEqual(100_000);
  });

  it("7. nessun provider disponibile → null", () => {
    _setTestDeps({ isAvailable: () => false });
    const result = route({ speed: true });
    expect(result).toBeNull();
  });

  it("8. DI isAvailable filtra i provider — solo groq disponibile → route = groq", () => {
    _setTestDeps({ isAvailable: (id) => id === "groq" });
    const result = route({ reasoning_depth: "high" });
    expect(result).not.toBeNull();
    expect(result!.provider).toBe("groq");
  });
});

// ─── rankAll ─────────────────────────────────────────────────────────────────

describe("rankAll", () => {
  it("9. ordina tutti i candidati per score decrescente", () => {
    const ranked = rankAll({ speed: true });
    expect(ranked.length).toBeGreaterThan(1);
    for (let i = 0; i < ranked.length - 1; i++) {
      expect(ranked[i].score).toBeGreaterThanOrEqual(ranked[i + 1].score);
    }
  });
});

// ─── scoreProfile ─────────────────────────────────────────────────────────────

describe("scoreProfile", () => {
  it("10. score > 0 per profilo compatibile con request", () => {
    const gemini = CAPABILITY_PROFILES["gemini"];
    const score = scoreProfile(gemini, { reasoning_depth: "high", code: true });
    expect(score).toBeGreaterThan(0);
  });

  it("11. score molto negativo per vision req su provider senza vision (groq)", () => {
    const groq = CAPABILITY_PROFILES["groq"];
    const score = scoreProfile(groq, { vision: true });
    expect(score).toBeLessThan(-50);
  });

  it("11b. score molto negativo per requires_tools su provider senza tools (browser-llm)", () => {
    const browserLlm = CAPABILITY_PROFILES["browser-llm"];
    const score = scoreProfile(browserLlm, { requires_tools: true });
    expect(score).toBeLessThan(-50);
  });
});

// ─── getProfile / getAllProfiles ───────────────────────────────────────────────

describe("getProfile / getAllProfiles", () => {
  it("12. getProfile ritorna profilo valido per ogni ProviderId", () => {
    // S342: incluso cerebras (aggiunto in S325 — 2000+ tok/s, fast-chat senza tools)
    const ids = ["gemini", "openai", "groq", "openrouter", "huggingface", "together", "browser-llm", "cerebras", "sambanova"] as const;
    for (const id of ids) {
      const p = getProfile(id);
      expect(p.id).toBe(id);
      expect(p.reasoning_score).toBeGreaterThanOrEqual(0);
      expect(p.reasoning_score).toBeLessThanOrEqual(10);
      expect(p.speed_score).toBeGreaterThanOrEqual(0);
      expect(p.speed_score).toBeLessThanOrEqual(10);
      expect(p.code_score).toBeGreaterThanOrEqual(0);
      expect(p.code_score).toBeLessThanOrEqual(10);
      expect(p.max_context).toBeGreaterThan(0);
      expect(typeof p.vision).toBe("boolean");
      expect(typeof p.free).toBe("boolean");
      expect(typeof p.tools).toBe("boolean");
    }
  });

  it("12b. getAllProfiles ritorna 9 profili (uno per provider, incluso cerebras S325 + sambanova S422)", () => {
    const profiles = getAllProfiles();
    // S342: 9 provider = gemini, openai, groq, openrouter, huggingface, together, browser-llm, cerebras, sambanova (S422/S502-FIX)
    expect(profiles).toHaveLength(9);
    const ids = profiles.map(p => p.id);
    const unique = new Set(ids);
    expect(unique.size).toBe(8);
    // Invariante: cerebras deve essere presente (aggiunto S325)
    expect(ids).toContain("cerebras");
    // Invariante: sambanova deve essere presente (aggiunto S422, inserito in ALL_PROVIDERS in S502-FIX)
    expect(ids).toContain("sambanova");
  });
});

// ─── buildReason ──────────────────────────────────────────────────────────────

describe("buildReason", () => {
  it("buildReason include dettagli rilevanti per il request", () => {
    const gemini = CAPABILITY_PROFILES["gemini"];
    const reason = buildReason(gemini, { reasoning_depth: "high", vision: true });
    expect(reason).toContain("gemini");
    expect(reason).toContain("reasoning");
    expect(reason).toContain("vision");
  });

  it("buildReason funziona anche con request vuoto", () => {
    const groq = CAPABILITY_PROFILES["groq"];
    const reason = buildReason(groq, {});
    expect(typeof reason).toBe("string");
    expect(reason.length).toBeGreaterThan(0);
  });
});