'use strict';

const assert = require('assert/strict');
const {
  MISSING_TIMESTAMP,
  conversationTimestamp,
  compareConversationRecency,
  sortConversationsByRecency,
  maxConversationTimestamp,
} = require('../mcp/src/core/conversation-order');

function main() {
  assert.equal(conversationTimestamp(null), MISSING_TIMESTAMP);
  assert.equal(conversationTimestamp(''), MISSING_TIMESTAMP);
  assert.equal(conversationTimestamp('not-a-time'), MISSING_TIMESTAMP);

  const mixed = [
    { id: 'private-old', channelType: 'private', lastMessageAt: '2026-08-04T08:00:00.000Z' },
    { id: 'group-new', channelType: 'group', lastMessageAt: '2026-08-04T10:00:00.000Z' },
    { id: 'private-invalid', channelType: 'private', lastMessageAt: 'not-a-time' },
    { id: 'group-empty', channelType: 'group', lastMessageAt: '' },
    { id: 'private-null', channelType: 'private', lastMessageAt: null },
  ];
  const sorted = sortConversationsByRecency(mixed);
  assert.deepEqual(sorted.map(item => item.id), [
    'group-new',
    'private-old',
    'private-invalid',
    'group-empty',
    'private-null',
  ]);
  assert.deepEqual(mixed.map(item => item.id), [
    'private-old',
    'group-new',
    'private-invalid',
    'group-empty',
    'private-null',
  ]);

  const sameTime = [
    { id: 'private-first', channelType: 'private', lastMessageAt: '2026-08-04T09:00:00.000Z' },
    { id: 'group-second', channelType: 'group', lastMessageAt: '2026-08-04T09:00:00.000Z' },
    { id: 'private-third', channelType: 'private', lastMessageAt: '2026-08-04T09:00:00.000Z' },
  ];
  assert.deepEqual(sortConversationsByRecency(sameTime).map(item => item.id), [
    'private-first',
    'group-second',
    'private-third',
  ]);

  assert(compareConversationRecency(mixed[1], mixed[0]) < 0);
  assert(compareConversationRecency(mixed[2], mixed[3]) === 0);

  assert.equal(maxConversationTimestamp(
    null,
    'not-a-time',
    '2026-08-04T08:00:00.000Z',
    '2026-08-04T10:00:00.000Z',
    '2026-08-04T09:00:00.000Z',
  ), '2026-08-04T10:00:00.000Z');
  assert.equal(maxConversationTimestamp(['', null, 'not-a-time']), null);

  process.stdout.write(`${JSON.stringify({ status: 'ok', checks: 6 }, null, 2)}\n`);
}

try { main(); }
catch (error) {
  process.stderr.write(`${error.stack || error.message}\n`);
  process.exit(1);
}