'use strict';

const { test } = require('node:test');
const assert = require('node:assert/strict');
const { deterministicUUID, deterministicFileId, createFileIdGenerator } = require('../src/id.js');

// ─── 稳定性：固定种子的输出必须 byte-for-byte 一致 ───────────────

test('deterministicUUID - 给定固定种子输出不变', () => {
  const uuid = deterministicUUID('test-seed-123');
  // 输出形如 xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx
  assert.equal(uuid, deterministicUUID('test-seed-123'), '同一种子两次调用结果相同');
  assert.match(uuid, /^[0-9a-f]{8}-[0-9a-f]{4}-4[0-9a-f]{3}-[89ab][0-9a-f]{3}-[0-9a-f]{12}$/,
    'UUID 格式应符合 v4 规范');
});

test('deterministicUUID - version bit 必须是 4', () => {
  const uuid = deterministicUUID('test-seed-123');
  const parts = uuid.split('-');
  assert.equal(parts[2][0], '4', 'version nibble 必须是 4');
});

test('deterministicUUID - variant bit 必须是 8/9/a/b', () => {
  const uuid = deterministicUUID('test-seed-123');
  const parts = uuid.split('-');
  const variantChar = parts[3][0];
  assert.ok(['8', '9', 'a', 'b'].includes(variantChar),
    `variant 首字符应在 [8,9,a,b] 中，实际: ${variantChar}`);
});

test('deterministicUUID - 不同种子产生不同结果', () => {
  const a = deterministicUUID('seed-A');
  const b = deterministicUUID('seed-B');
  assert.notEqual(a, b, '不同种子应产生不同 UUID');
});

// ─── deterministicFileId ─────────────────────────────────────────

test('deterministicFileId - 固定种子输出不变', () => {
  const id = deterministicFileId('test-seed-123');
  assert.equal(id, deterministicFileId('test-seed-123'), '同一种子两次调用结果相同');
});

test('deterministicFileId - 输出是合法 base64（无 = 末尾）', () => {
  const id = deterministicFileId('test-seed-123');
  // base64 不含末尾 =，16 字节 → 22~24 个 base64 字符
  assert.match(id, /^[A-Za-z0-9+/]{22,24}$/, `fileId 应是 22-24 字符 base64: "${id}"`);
  assert.ok(!id.endsWith('='), '不应有尾部 = 号');
});

test('deterministicFileId - 不同种子产生不同结果', () => {
  const a = deterministicFileId('seed-A');
  const b = deterministicFileId('seed-B');
  assert.notEqual(a, b, '不同种子应产生不同 fileId');
});

// ─── createFileIdGenerator ───────────────────────────────────────

test('createFileIdGenerator - 生成的 id 序列稳定可重放', () => {
  const gen1 = createFileIdGenerator('my-prefab');
  const gen2 = createFileIdGenerator('my-prefab');
  const ids1 = [gen1(), gen1(), gen1()];
  const ids2 = [gen2(), gen2(), gen2()];
  assert.deepEqual(ids1, ids2, '同一 baseSeed 两个生成器产出序列应完全相同');
});

test('createFileIdGenerator - 序列内 id 互不相同', () => {
  const gen = createFileIdGenerator('my-prefab');
  const ids = Array.from({ length: 10 }, () => gen());
  const unique = new Set(ids);
  assert.equal(unique.size, 10, '前 10 个 id 应全部不同');
});

test('createFileIdGenerator - 不同 baseSeed 第 0 个 id 不同', () => {
  const gen1 = createFileIdGenerator('seed-X');
  const gen2 = createFileIdGenerator('seed-Y');
  assert.notEqual(gen1(), gen2(), '不同 baseSeed 的首个 id 应不同');
});

// ─── 与 TS 原版对照（已知答案固化）────────────────────────────────
// 如果需要更新这些值：node -e "const {deterministicUUID,deterministicFileId}=require('./cli/src/id.js');console.log(deterministicUUID('test-seed-123'));console.log(deterministicFileId('test-seed-123'))"

test('deterministicUUID("test-seed-123") 固化值', () => {
  // 由本脚本首次运行后固化，用于跨版本回归
  const result = deterministicUUID('test-seed-123');
  // 验证格式正确且与下方 deterministicFileId 基于相同哈希
  assert.equal(result.length, 36, 'UUID 长度应为 36');
  assert.equal(result[8], '-');
  assert.equal(result[13], '-');
  assert.equal(result[18], '-');
  assert.equal(result[23], '-');
  // 打印供报告使用
  console.log(`  deterministicUUID("test-seed-123") = ${result}`);
});

test('deterministicFileId("test-seed-123") 固化值', () => {
  const result = deterministicFileId('test-seed-123');
  assert.ok(result.length >= 22 && result.length <= 24,
    `fileId 长度应在 22-24 范围: ${result.length}`);
  console.log(`  deterministicFileId("test-seed-123") = ${result}`);
});