import { describe, it, expect, afterEach, beforeEach, mock } from 'bun:test';
import { mkdirSync, writeFileSync, rmSync } from 'fs';
import { join } from 'path';
import { tmpdir } from 'os';
import { ConfigError } from '../utils/errors';

const TEST_DIR = join(tmpdir(), `planck-claw-config-test-${Date.now()}`);
const CONFIG_PATH = join(TEST_DIR, 'config.json');

mock.module('../utils/helpers', () => ({
  getHomeDir: () => TEST_DIR,
  getConfigDir: () => TEST_DIR,
  getConfigPath: () => CONFIG_PATH,
  getMemoryDir: () => join(TEST_DIR, 'memory'),
  getSkillsDir: () => join(TEST_DIR, 'skills'),
  getLogsDir: () => join(TEST_DIR, 'logs'),
  getCronJobsPath: () => join(TEST_DIR, 'cron.json'),
  sleep: (ms: number) => new Promise((r) => setTimeout(r, ms)),
  truncate: (text: string, max: number) => (text.length <= max ? text : text.slice(0, max - 3) + '...'),
  formatDate: (d: Date) => d.toISOString(),
  parseDate: (s: string) => new Date(s),
  generateId: () => crypto.randomUUID(),
}));

beforeEach(() => {
  mkdirSync(TEST_DIR, { recursive: true });
});

afterEach(() => {
  try { rmSync(TEST_DIR, { recursive: true, force: true }); } catch {}
});

describe('loadConfig', () => {
  it('throws ConfigError when config file does not exist', async () => {
    try { rmSync(CONFIG_PATH); } catch {}
    const { loadConfig } = await import('./index');
    expect(() => loadConfig()).toThrow(ConfigError);
    expect(() => loadConfig()).toThrow(/not found/);
  });

  it('throws ConfigError with descriptive message when JSON is invalid', async () => {
    writeFileSync(CONFIG_PATH, '{invalid json');
    const { loadConfig } = await import('./index');
    expect(() => loadConfig()).toThrow(/Invalid JSON/);
  });

  it('throws ConfigError with descriptive message when schema is invalid', async () => {
    writeFileSync(CONFIG_PATH, JSON.stringify({ agents: { defaults: { temperature: 999 } } }));
    const { loadConfig } = await import('./index');
    expect(() => loadConfig()).toThrow(/Invalid configuration schema/);
  });
});

describe('getConfigOrDefault', () => {
  it('returns default config when no config file exists', async () => {
    try { rmSync(CONFIG_PATH); } catch {}
    const { getConfigOrDefault } = await import('./index');
    const config = getConfigOrDefault();
    expect(config).toBeDefined();
    expect(config.agents).toBeDefined();
  });

  it('returns loaded config when file exists and is valid', async () => {
    const validConfig = {
      providers: {},
      agents: { defaults: { model: 'test/model', temperature: 0.5, maxTokens: 2048 } },
      tools: {},
    };
    writeFileSync(CONFIG_PATH, JSON.stringify(validConfig));
    const { getConfigOrDefault } = await import('./index');
    const config = getConfigOrDefault();
    expect(config.agents?.defaults?.maxTokens).toBe(2048);
  });
});