import assert from 'node:assert/strict';
import test from 'node:test';

import { MAX_CATCHUP, mailToEvent, selectCatchup } from '../lib/catchup.js';

const mail = (over = {}) => ({
  mail_id: 'm1',
  session_id: 's1',
  from_name: 'admin',
  subject: '主题',
  mail_type: 'normal',
  to_workspace: '/tmp/ws',
  ...over,
});

test('mailToEvent 产出与 SSE new_mail 同形的对象', () => {
  const ev = mailToEvent(mail());
  // 投递侧读的就是这几个键，形状不一致会让补拉那条路径静默地少带信息
  for (const k of ['mail_id', 'session_id', 'from_name', 'subject', 'mail_type', 'to_workspace']) {
    assert.ok(k in ev, `缺少 ${k}`);
  }
  assert.equal(ev.role, 'to');
  assert.equal(ev.catchup, true);
});

test('mailToEvent 对缺字段的行给出空串而非 undefined', () => {
  const ev = mailToEvent({});
  assert.equal(ev.mail_id, '');
  assert.equal(ev.to_workspace, '');
  assert.equal(ev.mail_type, 'normal');
});

test('已经通过 SSE 投过的不再补投', () => {
  const mails = [mail({ mail_id: 'a' }), mail({ mail_id: 'b' })];
  const got = selectCatchup(mails, new Set(['a']));
  assert.deepEqual(got.map(e => e.mail_id), ['b']);
});

test('按时间正序补投（收件箱是倒序返回的）', () => {
  // 收件箱：新的在前
  const mails = [mail({ mail_id: 'new' }), mail({ mail_id: 'mid' }), mail({ mail_id: 'old' })];
  const got = selectCatchup(mails, new Set());
  assert.deepEqual(
    got.map(e => e.mail_id),
    ['old', 'mid', 'new'],
    '先来的邮件必须先处理，否则同一会话里的上下文顺序是乱的',
  );
});

test('permission 类邮件不补投', () => {
  const mails = [mail({ mail_id: 'p', mail_type: 'permission' }), mail({ mail_id: 'n' })];
  const got = selectCatchup(mails, new Set());
  assert.deepEqual(got.map(e => e.mail_id), ['n']);
});

test('超过上限的部分留在收件箱里', () => {
  const mails = Array.from({ length: MAX_CATCHUP + 4 }, (_, i) => mail({ mail_id: 'm' + i }));
  const got = selectCatchup(mails, new Set());
  assert.equal(got.length, MAX_CATCHUP, '一次补拉不该把几十封邮件同时放出去');
});

test('上限可显式压到 0（用于禁用补拉）', () => {
  const got = selectCatchup([mail()], new Set(), 0);
  assert.deepEqual(got, []);
});

test('空输入与非数组不炸', () => {
  assert.deepEqual(selectCatchup([], new Set()), []);
  assert.deepEqual(selectCatchup(undefined, new Set()), []);
  assert.deepEqual(selectCatchup(null, new Set()), []);
});

test('没有 mail_id 的行跳过', () => {
  const got = selectCatchup([mail({ mail_id: '' }), mail({ mail_id: 'ok' })], new Set());
  assert.deepEqual(got.map(e => e.mail_id), ['ok']);
});

test('seen 传 undefined 时不去重也不报错', () => {
  const got = selectCatchup([mail({ mail_id: 'x' })], undefined);
  assert.deepEqual(got.map(e => e.mail_id), ['x']);
});

test('★ 补投事件必须带权限档位（漏了就会把 full 档会话误拦）', () => {
  const ev = mailToEvent(mail({ permission_mode: 'full', permission_enforcement: 'strict' }));
  assert.equal(ev.permission_mode, 'full', '补投路径不许把档位丢掉');
  assert.equal(ev.permission_enforcement, 'strict');
  // 缺字段时给空串：**不猜档位**（猜宽了就是提权），由调用方 `|| 'workspace'` 兜底
  const bare = mailToEvent(mail());
  assert.equal(bare.permission_mode, '');
  assert.equal(bare.permission_enforcement, '');
  assert.ok(!('permissionMode' in bare), '键名要与 SSE 逐字一致（蛇形），别自造驼峰');
});