/**
 * AI API Tests – Auth guard, validation, and service availability checks
 * Does NOT test actual OpenRouter API calls.
 */
import { describe, it, expect, beforeAll, afterAll } from 'vitest';
import type { FastifyInstance } from 'fastify';
import { SqliteAdapter } from '../src/database/SqliteAdapter.js';
import { createServer } from '../src/server.js';

describe('AI API', () => {
  let app: FastifyInstance;
  let db: SqliteAdapter;
  let authToken: string;

  beforeAll(async () => {
    db = new SqliteAdapter(':memory:');
    await db.init();
    app = await createServer({ db, port: 0 });
    await app.ready();

    // Register a user to get an auth token
    const registerRes = await app.inject({
      method: 'POST',
      url: '/api/auth/register',
      payload: {
        email: 'ai-test@example.com',
        password: 'TestPass123!',
        name: 'AI Test User',
        role: 'planer',
      },
    });
    const body = JSON.parse(registerRes.body);
    authToken = body.session.token;
  });

  afterAll(async () => {
    await app.close();
    db.close();
  });

  // ─── Auth Guard ─────────────────────────────────────

  describe('POST /api/ai/chat – Authentication', () => {
    it('should return 401 without authorization header', async () => {
      const response = await app.inject({
        method: 'POST',
        url: '/api/ai/chat',
        payload: { messages: [{ role: 'user', content: 'hello' }] },
      });
      expect(response.statusCode).toBe(401);
      const body = JSON.parse(response.body);
      expect(body.error).toContain('Authentication required');
    });

    it('should return 401 with invalid token', async () => {
      const response = await app.inject({
        method: 'POST',
        url: '/api/ai/chat',
        headers: { authorization: 'Bearer invalid-token-xxx' },
        payload: { messages: [{ role: 'user', content: 'hello' }] },
      });
      expect(response.statusCode).toBe(401);
      const body = JSON.parse(response.body);
      expect(body.error).toContain('Invalid or expired session');
    });

    it('should return 401 with malformed authorization header', async () => {
      const response = await app.inject({
        method: 'POST',
        url: '/api/ai/chat',
        headers: { authorization: 'NotBearer sometoken' },
        payload: { messages: [{ role: 'user', content: 'hello' }] },
      });
      expect(response.statusCode).toBe(401);
    });
  });

  // ─── Validation ─────────────────────────────────────

  describe('POST /api/ai/chat – Validation', () => {
    it('should return 400 when messages array is missing', async () => {
      const response = await app.inject({
        method: 'POST',
        url: '/api/ai/chat',
        headers: { authorization: `Bearer ${authToken}` },
        payload: {},
      });
      expect(response.statusCode).toBe(400);
      const body = JSON.parse(response.body);
      expect(body.error).toContain('Messages array is required');
    });

    it('should return 400 when messages array is empty', async () => {
      const response = await app.inject({
        method: 'POST',
        url: '/api/ai/chat',
        headers: { authorization: `Bearer ${authToken}` },
        payload: { messages: [] },
      });
      expect(response.statusCode).toBe(400);
      const body = JSON.parse(response.body);
      expect(body.error).toContain('Messages array is required');
    });

    it('should return 400 when messages is not an array', async () => {
      const response = await app.inject({
        method: 'POST',
        url: '/api/ai/chat',
        headers: { authorization: `Bearer ${authToken}` },
        payload: { messages: 'not an array' },
      });
      expect(response.statusCode).toBe(400);
    });
  });

  // ─── Service Availability ───────────────────────────

  describe('POST /api/ai/chat – Service availability', () => {
    it('should return 503 when API_KEY_OPENROUTER is not set', async () => {
      // Ensure env var is not set for this test
      const originalValue = process.env.API_KEY_OPENROUTER;
      delete process.env.API_KEY_OPENROUTER;

      const response = await app.inject({
        method: 'POST',
        url: '/api/ai/chat',
        headers: { authorization: `Bearer ${authToken}` },
        payload: { messages: [{ role: 'user', content: 'hello' }] },
      });
      expect(response.statusCode).toBe(503);
      const body = JSON.parse(response.body);
      expect(body.error).toContain('AI service not configured');

      // Restore original value if it existed
      if (originalValue !== undefined) {
        process.env.API_KEY_OPENROUTER = originalValue;
      }
    });
  });
});