import { defineConfig } from 'vitest/config'

/**
 * Vitest Configuration - Optimized for Memory-Intensive Tests
 *
 * Handles ONNX transformer model testing (4-8GB memory requirement)
 * Based on 2024-2025 best practices
 *
 * THE CORRECTNESS GATE: this is the config a bare `vitest run` (no
 * `--config` flag) picks up — the delta gate and CI both invoke it that
 * way. See CONTRIBUTING.md's "Test gate" section for the full picture.
 * Wall-clock/scale benchmarks and tests whose outcome depends on the host
 * machine or network rather than the code are excluded below and run on
 * demand instead, in their own slot: `npm run test:perf`.
 */
export default defineConfig({
  test: {
    globals: true,
    setupFiles: ['./tests/setup.ts'],
    environment: 'node',
    
    // MEMORY OPTIMIZATION: Use forks for better memory isolation
    pool: 'forks',
    poolOptions: {
      forks: {
        maxForks: 1,      // One test file at a time
        minForks: 1,
        singleFork: true, // Sequential execution
        isolate: true     // Isolate test files
      }
    },
    
    // TIMEOUTS: Extended for ONNX model loading
    testTimeout: 120000,  // 2 minutes per test
    hookTimeout: 60000,   // 1 minute for hooks
    teardownTimeout: 10000,
    
    // PARALLELISM: Disabled to prevent memory exhaustion
    maxConcurrency: 1,
    fileParallelism: false,
    
    // INCLUDE/EXCLUDE
    include: ['tests/**/*.{test,spec}.{js,ts}'],
    exclude: [
      'node_modules/**',
      'dist/**',
      'scripts/**',
      '**/*.browser.test.ts',

      // Wall-clock/scale benchmark family — timing assertions and scale
      // sweeps whose pass/fail depends on the host machine's speed, not on
      // the code. Whole files only (a file that mixes correctness describes
      // with a perf describe stays in the gate). Run on demand via
      // `npm run test:perf`, which targets exactly this list.
      'tests/performance/**',
      'tests/critical-performance-benchmark.test.ts',
      'tests/api/performance-benchmarks.test.ts',

      // Environment-dependent by construction, not timing-based:
      // package-size-limit shells out to the `npm` CLI (not guaranteed
      // present — the functional gate lane is Bun-only host-mode with no
      // Node.js runtime) and parses npm-version-specific `npm pack` notice
      // text; model-loading's "Real Model Download Integration" case makes
      // a genuine, unmocked network call to HuggingFace (its own header
      // says "Uses REAL transformer models - NO MOCKING"), and the whole
      // file imports `../src/embeddings/model-manager.js`, which no longer
      // exists anywhere under src/ — neither belongs in a gate that must be
      // deterministic.
      'tests/package-size-limit.test.ts',
      'tests/model-loading.test.ts'
    ],
    
    // REPORTERS: Dot for CI, verbose for local
    reporters: process.env.CI ? ['dot'] : ['default'],
    
    // RETRY: Once in CI for flaky tests
    retry: process.env.CI ? 1 : 0,
    
    // SHARDING: Support test splitting
    // Use: VITEST_SHARD=1/4 npm test
    shard: process.env.VITEST_SHARD
  }
})