import { test } from 'node:test';
import assert from 'node:assert/strict';
import { join } from 'node:path';
import { existsSync, readFileSync, writeFileSync } from 'node:fs';
import { makeTempMonorepo, cleanup } from './helpers.mjs';
import { ensureJunction, isLink } from '../lib/junction.mjs';

test('ensureJunction 创建链接后可经链接读到真源文件', () => {
  const mono = makeTempMonorepo();
  try {
    const link = join(mono.games, 'demo-framework');
    const status = ensureJunction(link, mono.framework);
    assert.equal(status, 'created');
    assert.ok(isLink(link));
    assert.equal(readFileSync(join(link, 'README.md'), 'utf8'), '# framework src\n');
  } finally {
    cleanup(mono.root);
  }
});

test('ensureJunction 对已存在链接返回 exists 且不抛错', () => {
  const mono = makeTempMonorepo();
  try {
    const link = join(mono.games, 'demo-framework');
    ensureJunction(link, mono.framework);
    assert.equal(ensureJunction(link, mono.framework), 'exists');
  } finally {
    cleanup(mono.root);
  }
});

test('ensureJunction 目标不存在时抛错', () => {
  const mono = makeTempMonorepo();
  try {
    assert.throws(() => ensureJunction(join(mono.games, 'x'), join(mono.root, 'no-such')), /target 不存在/);
  } finally {
    cleanup(mono.root);
  }
});

test('ensureJunction 拒绝覆盖已存在的真实目录/文件', () => {
  const mono = makeTempMonorepo();
  try {
    const link = join(mono.games, 'realfile');
    writeFileSync(link, 'x');
    assert.throws(() => ensureJunction(link, mono.framework), /非链接/);
  } finally {
    cleanup(mono.root);
  }
});