import { describe, it, expect, beforeEach, afterEach, vi } from 'vitest';
import { initDb, getDb } from '../../db/index.js';
import { encrypt } from '../../lib/crypto.js';
import { resolveFamily, getDefaultFamily, runEmbeddings, EmbeddingsError } from '../../services/embeddings.js';

const realFetch = globalThis.fetch;

function addKey(platform: string, raw = `${platform}-test-key`) {
  const { encrypted, iv, authTag } = encrypt(raw);
  getDb().prepare(`
    INSERT INTO api_keys (platform, label, encrypted_key, iv, auth_tag, status, enabled)
    VALUES (?, 'test', ?, ?, ?, 'healthy', 1)
  `).run(platform, encrypted, iv, authTag);
}

function okEmbeddingResponse(dims: number, count = 1) {
  return new Response(JSON.stringify({
    data: Array.from({ length: count }, (_, i) => ({ index: i, embedding: Array(dims).fill(0.1) })),
    usage: { prompt_tokens: 3 },
  }), { status: 200, headers: { 'Content-Type': 'application/json' } });
}

describe('embeddings service', () => {
  beforeEach(() => {
    process.env.ENCRYPTION_KEY = '0'.repeat(64);
    initDb(':memory:');
  });

  afterEach(() => {
    globalThis.fetch = realFetch;
    vi.restoreAllMocks();
  });

  describe('migration seed', () => {
    it('seeds the embedding catalog with families and a default', () => {
      const rows = getDb().prepare('SELECT DISTINCT family FROM embedding_models').all() as { family: string }[];
      const families = rows.map(r => r.family);
      expect(families).toContain('gemini-embedding-001');
      expect(families).toContain('llama-nemotron-embed-vl-1b-v2');
      expect(families).toContain('bge-m3');
      expect(getDefaultFamily()).toBe('gemini-embedding-001');
    });

    it('cohere is seeded disabled (its quota is shared with chat)', () => {
      const row = getDb().prepare("SELECT enabled FROM embedding_models WHERE platform = 'cohere'").get() as { enabled: number };
      expect(row.enabled).toBe(0);
    });

    it('multi-provider families share one dimension', () => {
      const dims = getDb().prepare(
        "SELECT DISTINCT dimensions FROM embedding_models WHERE family = 'llama-nemotron-embed-vl-1b-v2'",
      ).all();
      expect(dims).toHaveLength(1);
    });
  });

  describe('resolveFamily', () => {
    it("maps 'auto', empty and undefined to the default family", () => {
      expect(resolveFamily('auto')).toBe('gemini-embedding-001');
      expect(resolveFamily('')).toBe('gemini-embedding-001');
      expect(resolveFamily(undefined)).toBe('gemini-embedding-001');
    });

    it('accepts a family name directly', () => {
      expect(resolveFamily('bge-m3')).toBe('bge-m3');
    });

    it('maps a provider-specific model id to its family', () => {
      expect(resolveFamily('@cf/baai/bge-m3')).toBe('bge-m3');
      expect(resolveFamily('nvidia/llama-nemotron-embed-vl-1b-v2')).toBe('llama-nemotron-embed-vl-1b-v2');
    });

    it('returns null for unknown models', () => {
      expect(resolveFamily('text-embedding-ada-002')).toBeNull();
    });
  });

  describe('runEmbeddings', () => {
    it('rejects unknown models with a 400', async () => {
      await expect(runEmbeddings('no-such-model', ['hi'])).rejects.toMatchObject({ status: 400 });
    });

    it('embeds via the first provider in the family chain', async () => {
      addKey('nvidia');
      addKey('openrouter');
      const fetchMock = vi.fn(async () => okEmbeddingResponse(2048));
      globalThis.fetch = fetchMock as any;

      const result = await runEmbeddings('llama-nemotron-embed-vl-1b-v2', ['hello']);
      expect(result.platform).toBe('nvidia');
      expect(result.dimensions).toBe(2048);
      expect(result.vectors).toHaveLength(1);
      expect(fetchMock).toHaveBeenCalledTimes(1);
      expect(String(fetchMock.mock.calls[0][0])).toContain('integrate.api.nvidia.com');
    });

    it('fails over WITHIN the family when the first provider errors', async () => {
      addKey('nvidia');
      addKey('openrouter');
      const fetchMock = vi.fn()
        .mockResolvedValueOnce(new Response('rate limited', { status: 429 }))
        .mockResolvedValueOnce(okEmbeddingResponse(2048));
      globalThis.fetch = fetchMock as any;

      const result = await runEmbeddings('llama-nemotron-embed-vl-1b-v2', ['hello']);
      expect(result.platform).toBe('openrouter');
      expect(fetchMock).toHaveBeenCalledTimes(2);
      expect(String(fetchMock.mock.calls[1][0])).toContain('openrouter.ai');
    });

    it('skips providers without a usable key instead of failing', async () => {
      addKey('openrouter'); // no nvidia key
      const fetchMock = vi.fn(async () => okEmbeddingResponse(2048));
      globalThis.fetch = fetchMock as any;

      const result = await runEmbeddings('llama-nemotron-embed-vl-1b-v2', ['hello']);
      expect(result.platform).toBe('openrouter');
      expect(fetchMock).toHaveBeenCalledTimes(1);
    });

    it('throws 429 when every provider is rate-limited', async () => {
      addKey('nvidia');
      addKey('openrouter');
      globalThis.fetch = vi.fn(async () => new Response('slow down', { status: 429 })) as any;

      await expect(runEmbeddings('llama-nemotron-embed-vl-1b-v2', ['hello'])).rejects.toMatchObject({ status: 429 });
    });

    it('throws 503 when the family has no enabled providers', async () => {
      getDb().prepare("UPDATE embedding_models SET enabled = 0 WHERE family = 'bge-m3'").run();
      await expect(runEmbeddings('bge-m3', ['hello'])).rejects.toMatchObject({ status: 503 });
    });

    it('splits cloudflare account_id:token keys', async () => {
      addKey('cloudflare', 'acct-123:cf-token-xyz');
      const fetchMock = vi.fn(async () => okEmbeddingResponse(1024));
      globalThis.fetch = fetchMock as any;

      const result = await runEmbeddings('embeddinggemma-300m', ['hello']);
      expect(result.platform).toBe('cloudflare');
      expect(String(fetchMock.mock.calls[0][0])).toContain('/accounts/acct-123/ai/v1/embeddings');
      const headers = (fetchMock.mock.calls[0][1] as RequestInit).headers as Record<string, string>;
      expect(headers.Authorization).toBe('Bearer cf-token-xyz');
    });

    it('normalizes hugging face feature-extraction output', async () => {
      // bge-m3: cloudflare first (no key) → falls through to huggingface
      addKey('huggingface');
      const fetchMock = vi.fn(async () => new Response(JSON.stringify([[0.1, 0.2, 0.3]]), { status: 200 }));
      globalThis.fetch = fetchMock as any;

      const result = await runEmbeddings('bge-m3', ['hello']);
      expect(result.platform).toBe('huggingface');
      expect(result.dimensions).toBe(3);
      expect(String(fetchMock.mock.calls[0][0])).toContain('feature-extraction');
    });

    it('rejects malformed upstream payloads and fails over', async () => {
      addKey('nvidia');
      addKey('openrouter');
      const fetchMock = vi.fn()
        .mockResolvedValueOnce(new Response(JSON.stringify({ data: [] }), { status: 200 })) // wrong count
        .mockResolvedValueOnce(okEmbeddingResponse(2048));
      globalThis.fetch = fetchMock as any;

      const result = await runEmbeddings('llama-nemotron-embed-vl-1b-v2', ['hello']);
      expect(result.platform).toBe('openrouter');
    });

    it("logs requests tagged request_type='embedding' so chat budgets ignore them", async () => {
      addKey('nvidia');
      addKey('openrouter');
      const fetchMock = vi.fn()
        .mockResolvedValueOnce(new Response('boom', { status: 500 }))
        .mockResolvedValueOnce(okEmbeddingResponse(2048));
      globalThis.fetch = fetchMock as any;

      await runEmbeddings('llama-nemotron-embed-vl-1b-v2', ['hello']);
      const rows = getDb().prepare(
        "SELECT platform, status, request_type FROM requests ORDER BY id",
      ).all() as { platform: string; status: string; request_type: string }[];
      expect(rows).toEqual([
        { platform: 'nvidia', status: 'error', request_type: 'embedding' },
        { platform: 'openrouter', status: 'success', request_type: 'embedding' },
      ]);

      // and the chat-scoped monthly usage query sees none of it
      const chatUsed = getDb().prepare(`
        SELECT COALESCE(SUM(input_tokens + output_tokens), 0) AS used
        FROM requests
        WHERE created_at >= datetime('now', 'start of month') AND request_type = 'chat'
      `).get() as { used: number };
      expect(chatUsed.used).toBe(0);
    });
  });
});