/**
 * Tests for hook-command error classifier
 *
 * Validates that isWorkerUnavailableError correctly distinguishes between:
 * - Transport failures (ECONNREFUSED, etc.) → true (graceful degradation)
 * - Server errors (5xx) → true (graceful degradation)
 * - Client errors (4xx) → false (handler bug, blocking)
 * - Programming errors (TypeError, etc.) → false (code bug, blocking)
 */
import { describe, it, expect } from 'bun:test';
import { isWorkerUnavailableError } from '../src/cli/hook-command.js';

describe('isWorkerUnavailableError', () => {
  describe('transport failures → true (graceful)', () => {
    it('should classify ECONNREFUSED as worker unavailable', () => {
      const error = new Error('connect ECONNREFUSED 127.0.0.1:37777');
      expect(isWorkerUnavailableError(error)).toBe(true);
    });

    it('should classify ECONNRESET as worker unavailable', () => {
      const error = new Error('socket hang up ECONNRESET');
      expect(isWorkerUnavailableError(error)).toBe(true);
    });

    it('should classify EPIPE as worker unavailable', () => {
      const error = new Error('write EPIPE');
      expect(isWorkerUnavailableError(error)).toBe(true);
    });

    it('should classify ETIMEDOUT as worker unavailable', () => {
      const error = new Error('connect ETIMEDOUT 127.0.0.1:37777');
      expect(isWorkerUnavailableError(error)).toBe(true);
    });

    it('should classify "fetch failed" as worker unavailable', () => {
      const error = new TypeError('fetch failed');
      expect(isWorkerUnavailableError(error)).toBe(true);
    });

    it('should classify "Unable to connect" as worker unavailable', () => {
      const error = new Error('Unable to connect to server');
      expect(isWorkerUnavailableError(error)).toBe(true);
    });

    it('should classify ENOTFOUND as worker unavailable', () => {
      const error = new Error('getaddrinfo ENOTFOUND localhost');
      expect(isWorkerUnavailableError(error)).toBe(true);
    });

    it('should classify "socket hang up" as worker unavailable', () => {
      const error = new Error('socket hang up');
      expect(isWorkerUnavailableError(error)).toBe(true);
    });

    it('should classify ECONNABORTED as worker unavailable', () => {
      const error = new Error('ECONNABORTED');
      expect(isWorkerUnavailableError(error)).toBe(true);
    });
  });

  describe('timeout errors → true (graceful)', () => {
    it('should classify "timed out" as worker unavailable', () => {
      const error = new Error('Request timed out after 3000ms');
      expect(isWorkerUnavailableError(error)).toBe(true);
    });

    it('should classify "timeout" as worker unavailable', () => {
      const error = new Error('Connection timeout');
      expect(isWorkerUnavailableError(error)).toBe(true);
    });
  });

  describe('HTTP 5xx server errors → true (graceful)', () => {
    it('should classify 500 status as worker unavailable', () => {
      const error = new Error('Context generation failed: 500');
      expect(isWorkerUnavailableError(error)).toBe(true);
    });

    it('should classify 502 status as worker unavailable', () => {
      const error = new Error('Observation storage failed: 502');
      expect(isWorkerUnavailableError(error)).toBe(true);
    });

    it('should classify 503 status as worker unavailable', () => {
      const error = new Error('Request failed: 503');
      expect(isWorkerUnavailableError(error)).toBe(true);
    });

    it('should classify "status: 500" format as worker unavailable', () => {
      const error = new Error('HTTP error status: 500');
      expect(isWorkerUnavailableError(error)).toBe(true);
    });
  });

  describe('HTTP 429 rate limit → true (graceful)', () => {
    it('should classify 429 as worker unavailable (rate limit is transient)', () => {
      const error = new Error('Request failed: 429');
      expect(isWorkerUnavailableError(error)).toBe(true);
    });

    it('should classify "status: 429" format as worker unavailable', () => {
      const error = new Error('HTTP error status: 429');
      expect(isWorkerUnavailableError(error)).toBe(true);
    });
  });

  describe('HTTP 4xx client errors → false (blocking)', () => {
    it('should NOT classify 400 Bad Request as worker unavailable', () => {
      const error = new Error('Request failed: 400');
      expect(isWorkerUnavailableError(error)).toBe(false);
    });

    it('should NOT classify 404 Not Found as worker unavailable', () => {
      const error = new Error('Observation storage failed: 404');
      expect(isWorkerUnavailableError(error)).toBe(false);
    });

    it('should NOT classify 422 Validation Error as worker unavailable', () => {
      const error = new Error('Request failed: 422');
      expect(isWorkerUnavailableError(error)).toBe(false);
    });

    it('should NOT classify "status: 400" format as worker unavailable', () => {
      const error = new Error('HTTP error status: 400');
      expect(isWorkerUnavailableError(error)).toBe(false);
    });
  });

  describe('programming errors → false (blocking)', () => {
    it('should NOT classify TypeError as worker unavailable', () => {
      const error = new TypeError('Cannot read properties of undefined');
      // Note: TypeError with "fetch failed" IS classified as unavailable (transport layer)
      // But generic TypeErrors are NOT
      expect(isWorkerUnavailableError(new TypeError('Cannot read properties of undefined'))).toBe(false);
    });

    it('should NOT classify ReferenceError as worker unavailable', () => {
      const error = new ReferenceError('foo is not defined');
      expect(isWorkerUnavailableError(error)).toBe(false);
    });

    it('should NOT classify SyntaxError as worker unavailable', () => {
      const error = new SyntaxError('Unexpected token');
      expect(isWorkerUnavailableError(error)).toBe(false);
    });
  });

  describe('unknown errors → false (blocking, conservative)', () => {
    it('should NOT classify generic Error as worker unavailable', () => {
      const error = new Error('Something unexpected happened');
      expect(isWorkerUnavailableError(error)).toBe(false);
    });

    it('should handle string errors', () => {
      expect(isWorkerUnavailableError('ECONNREFUSED')).toBe(true);
      expect(isWorkerUnavailableError('random error')).toBe(false);
    });

    it('should handle null/undefined errors', () => {
      expect(isWorkerUnavailableError(null)).toBe(false);
      expect(isWorkerUnavailableError(undefined)).toBe(false);
    });
  });
});