dcrouter/test/suite/smtpclient_email-composition/test.cep-06.utf8-international.ts

import { tap, expect } from '@git.zone/tstest/tapbundle';
import { startTestSmtpServer } from '../../helpers/server.loader.js';
import { createSmtpClient } from '../../helpers/smtp.client.js';
import { Email } from '../../../ts/mail/core/classes.email.js';

let testServer: any;

tap.test('setup test SMTP server', async () => {
  testServer = await startTestSmtpServer({
    features: ['8BITMIME', 'SMTPUTF8'] // Enable UTF-8 support
  });
  expect(testServer).toBeTruthy();
  expect(testServer.port).toBeGreaterThan(0);
});

tap.test('CEP-06: Basic UTF-8 content', async () => {
  const smtpClient = createSmtpClient({
    host: testServer.hostname,
    port: testServer.port,
    secure: false,
    connectionTimeout: 5000,
    debug: true
  });

  await smtpClient.connect();

  // Create email with UTF-8 content
  const email = new Email({
    from: 'sender@example.com',
    to: ['recipient@example.com'],
    subject: 'UTF-8 Test: こんにちは 🌍',
    text: 'Hello in multiple languages:\n' +
          'English: Hello World\n' +
          'Japanese: こんにちは世界\n' +
          'Chinese: 你好世界\n' +
          'Arabic: مرحبا بالعالم\n' +
          'Russian: Привет мир\n' +
          'Emoji: 🌍🌎🌏✉️📧'
  });

  // Check content encoding
  let contentType = '';
  let charset = '';
  const originalSendCommand = smtpClient.sendCommand.bind(smtpClient);
  
  smtpClient.sendCommand = async (command: string) => {
    if (command.toLowerCase().includes('content-type:')) {
      contentType = command;
      const charsetMatch = command.match(/charset=([^;\s]+)/i);
      if (charsetMatch) {
        charset = charsetMatch[1];
      }
    }
    return originalSendCommand(command);
  };

  const result = await smtpClient.sendMail(email);
  expect(result).toBeTruthy();
  
  console.log('Content-Type:', contentType.trim());
  console.log('Charset:', charset || 'not specified');
  
  // Should use UTF-8 charset
  expect(charset.toLowerCase()).toMatch(/utf-?8/);

  await smtpClient.close();
});

tap.test('CEP-06: International email addresses', async () => {
  const smtpClient = createSmtpClient({
    host: testServer.hostname,
    port: testServer.port,
    secure: false,
    connectionTimeout: 5000,
    debug: true
  });

  await smtpClient.connect();

  // Check if server supports SMTPUTF8
  const ehloResponse = await smtpClient.sendCommand('EHLO testclient.example.com');
  const supportsSmtpUtf8 = ehloResponse.includes('SMTPUTF8');
  console.log('Server supports SMTPUTF8:', supportsSmtpUtf8);

  // Test international email addresses
  const internationalAddresses = [
    'user@例え.jp',
    'utilisateur@exemple.fr',
    'benutzer@beispiel.de',
    'пользователь@пример.рф',
    '用户@例子.中国'
  ];

  for (const address of internationalAddresses) {
    console.log(`\nTesting international address: ${address}`);
    
    const email = new Email({
      from: 'sender@example.com',
      to: [address],
      subject: 'International Address Test',
      text: `Testing delivery to: ${address}`
    });

    try {
      // Monitor MAIL FROM with SMTPUTF8
      let smtpUtf8Used = false;
      const originalSendCommand = smtpClient.sendCommand.bind(smtpClient);
      
      smtpClient.sendCommand = async (command: string) => {
        if (command.includes('SMTPUTF8')) {
          smtpUtf8Used = true;
        }
        return originalSendCommand(command);
      };

      const result = await smtpClient.sendMail(email);
      console.log(`  Result: ${result ? 'Success' : 'Failed'}`);
      console.log(`  SMTPUTF8 used: ${smtpUtf8Used}`);
      
      if (!supportsSmtpUtf8 && !result) {
        console.log('  Expected failure - server does not support SMTPUTF8');
      }
    } catch (error) {
      console.log(`  Error: ${error.message}`);
      if (!supportsSmtpUtf8) {
        console.log('  Expected - server does not support international addresses');
      }
    }
  }

  await smtpClient.close();
});

tap.test('CEP-06: UTF-8 in headers', async () => {
  const smtpClient = createSmtpClient({
    host: testServer.hostname,
    port: testServer.port,
    secure: false,
    connectionTimeout: 5000,
    debug: true
  });

  await smtpClient.connect();

  // Create email with UTF-8 in various headers
  const email = new Email({
    from: '"发件人" <sender@example.com>',
    to: ['"收件人" <recipient@example.com>'],
    subject: 'Meeting: Café ☕ at 3pm 🕒',
    headers: {
      'X-Custom-Header': 'Custom UTF-8: αβγδε',
      'X-Language': '日本語'
    },
    text: 'Meeting at the café to discuss the project.'
  });

  // Capture encoded headers
  const capturedHeaders: string[] = [];
  const originalSendCommand = smtpClient.sendCommand.bind(smtpClient);
  
  smtpClient.sendCommand = async (command: string) => {
    if (command.includes(':') && !command.startsWith('MAIL') && !command.startsWith('RCPT')) {
      capturedHeaders.push(command);
    }
    return originalSendCommand(command);
  };

  await smtpClient.sendMail(email);

  console.log('\nCaptured headers with UTF-8:');
  capturedHeaders.forEach(header => {
    // Check for encoded-word syntax (RFC 2047)
    if (header.includes('=?')) {
      const encodedMatch = header.match(/=\?([^?]+)\?([BQ])\?([^?]+)\?=/);
      if (encodedMatch) {
        console.log(`  Encoded header: ${header.substring(0, 50)}...`);
        console.log(`    Charset: ${encodedMatch[1]}, Encoding: ${encodedMatch[2]}`);
      }
    } else if (/[\u0080-\uFFFF]/.test(header)) {
      console.log(`  Raw UTF-8 header: ${header.substring(0, 50)}...`);
    }
  });

  await smtpClient.close();
});

tap.test('CEP-06: Different character encodings', async () => {
  const smtpClient = createSmtpClient({
    host: testServer.hostname,
    port: testServer.port,
    secure: false,
    connectionTimeout: 5000,
    debug: true
  });

  await smtpClient.connect();

  // Test different encoding scenarios
  const encodingTests = [
    {
      name: 'Plain ASCII',
      subject: 'Simple ASCII Subject',
      text: 'This is plain ASCII text.',
      expectedEncoding: 'none'
    },
    {
      name: 'Latin-1 characters',
      subject: 'Café, naïve, résumé',
      text: 'Text with Latin-1: àáâãäåæçèéêë',
      expectedEncoding: 'quoted-printable or base64'
    },
    {
      name: 'CJK characters',
      subject: '会議の予定：明日',
      text: '明日の会議は午後3時からです。',
      expectedEncoding: 'base64'
    },
    {
      name: 'Mixed scripts',
      subject: 'Hello 你好 مرحبا',
      text: 'Mixed: English, 中文, العربية, Русский',
      expectedEncoding: 'base64'
    },
    {
      name: 'Emoji heavy',
      subject: '🎉 Party Time 🎊',
      text: '🌟✨🎈🎁🎂🍰🎵🎶💃🕺',
      expectedEncoding: 'base64'
    }
  ];

  for (const test of encodingTests) {
    console.log(`\nTesting: ${test.name}`);
    
    const email = new Email({
      from: 'sender@example.com',
      to: ['recipient@example.com'],
      subject: test.subject,
      text: test.text
    });

    let transferEncoding = '';
    let subjectEncoding = '';
    const originalSendCommand = smtpClient.sendCommand.bind(smtpClient);
    
    smtpClient.sendCommand = async (command: string) => {
      if (command.toLowerCase().includes('content-transfer-encoding:')) {
        transferEncoding = command.split(':')[1].trim();
      }
      if (command.toLowerCase().startsWith('subject:')) {
        if (command.includes('=?')) {
          subjectEncoding = 'encoded-word';
        } else {
          subjectEncoding = 'raw';
        }
      }
      return originalSendCommand(command);
    };

    await smtpClient.sendMail(email);
    
    console.log(`  Subject encoding: ${subjectEncoding}`);
    console.log(`  Body transfer encoding: ${transferEncoding}`);
    console.log(`  Expected: ${test.expectedEncoding}`);
  }

  await smtpClient.close();
});

tap.test('CEP-06: Line length handling for UTF-8', async () => {
  const smtpClient = createSmtpClient({
    host: testServer.hostname,
    port: testServer.port,
    secure: false,
    connectionTimeout: 5000,
    debug: true
  });

  await smtpClient.connect();

  // Create long lines with UTF-8 characters
  const longJapanese = '日本語のテキスト'.repeat(20); // ~300 bytes
  const longEmoji = '😀😃😄😁😆😅😂🤣'.repeat(25); // ~800 bytes
  
  const email = new Email({
    from: 'sender@example.com',
    to: ['recipient@example.com'],
    subject: 'Long UTF-8 Lines Test',
    text: `Short line\n${longJapanese}\nAnother short line\n${longEmoji}\nEnd`
  });

  // Monitor line lengths
  let maxLineLength = 0;
  let longLines = 0;
  const originalSendCommand = smtpClient.sendCommand.bind(smtpClient);
  let inData = false;
  
  smtpClient.sendCommand = async (command: string) => {
    if (command === 'DATA') {
      inData = true;
    } else if (command === '.') {
      inData = false;
    } else if (inData) {
      const lines = command.split('\r\n');
      lines.forEach(line => {
        const byteLength = Buffer.byteLength(line, 'utf8');
        maxLineLength = Math.max(maxLineLength, byteLength);
        if (byteLength > 78) { // RFC recommended line length
          longLines++;
        }
      });
    }
    return originalSendCommand(command);
  };

  await smtpClient.sendMail(email);
  
  console.log(`\nLine length analysis:`);
  console.log(`  Maximum line length: ${maxLineLength} bytes`);
  console.log(`  Lines over 78 bytes: ${longLines}`);
  
  // Lines should be properly wrapped or encoded
  if (maxLineLength > 998) { // RFC hard limit
    console.log('  WARNING: Lines exceed RFC 5321 limit of 998 bytes');
  }

  await smtpClient.close();
});

tap.test('CEP-06: Bidirectional text handling', async () => {
  const smtpClient = createSmtpClient({
    host: testServer.hostname,
    port: testServer.port,
    secure: false,
    connectionTimeout: 5000,
    debug: true
  });

  await smtpClient.connect();

  // Test bidirectional text (RTL and LTR mixed)
  const email = new Email({
    from: 'sender@example.com',
    to: ['recipient@example.com'],
    subject: 'مرحبا Hello שלום',
    text: 'Mixed direction text:\n' +
          'English text followed by عربي ثم עברית\n' +
          'מספרים: 123 أرقام: ٤٥٦\n' +
          'LTR: Hello → RTL: مرحبا ← LTR: World'
  });

  const result = await smtpClient.sendMail(email);
  expect(result).toBeTruthy();
  
  console.log('Successfully sent email with bidirectional text');

  await smtpClient.close();
});

tap.test('CEP-06: Special UTF-8 cases', async () => {
  const smtpClient = createSmtpClient({
    host: testServer.hostname,
    port: testServer.port,
    secure: false,
    connectionTimeout: 5000,
    debug: true
  });

  await smtpClient.connect();

  // Test special UTF-8 cases
  const specialCases = [
    {
      name: 'Zero-width characters',
      text: 'Visible‌Zero‌Width‌Non‌Joiner‌Between‌Words'
    },
    {
      name: 'Combining characters',
      text: 'a\u0300 e\u0301 i\u0302 o\u0303 u\u0308' // à é î õ ü
    },
    {
      name: 'Surrogate pairs',
      text: '𝐇𝐞𝐥𝐥𝐨 𝕎𝕠𝕣𝕝𝕕 🏴󠁧󠁢󠁳󠁣󠁴󠁿' // Mathematical bold, flags
    },
    {
      name: 'Right-to-left marks',
      text: '\u202Edetrevni si txet sihT\u202C' // RTL override
    },
    {
      name: 'Non-standard spaces',
      text: 'Different spaces: \u2000\u2001\u2002\u2003\u2004'
    }
  ];

  for (const testCase of specialCases) {
    console.log(`\nTesting ${testCase.name}`);
    
    const email = new Email({
      from: 'sender@example.com',
      to: ['recipient@example.com'],
      subject: `UTF-8 Special: ${testCase.name}`,
      text: testCase.text
    });

    try {
      const result = await smtpClient.sendMail(email);
      console.log(`  Result: ${result ? 'Success' : 'Failed'}`);
      console.log(`  Text bytes: ${Buffer.byteLength(testCase.text, 'utf8')}`);
    } catch (error) {
      console.log(`  Error: ${error.message}`);
    }
  }

  await smtpClient.close();
});

tap.test('CEP-06: Fallback encoding for non-UTF8 servers', async () => {
  const smtpClient = createSmtpClient({
    host: testServer.hostname,
    port: testServer.port,
    secure: false,
    connectionTimeout: 5000,
    preferredEncoding: 'quoted-printable', // Force specific encoding
    debug: true
  });

  await smtpClient.connect();

  // Send UTF-8 content that needs encoding
  const email = new Email({
    from: 'sender@example.com',
    to: ['recipient@example.com'],
    subject: 'Fallback Encoding: Café français',
    text: 'Testing encoding: àèìòù ÀÈÌÒÙ äëïöü ñç'
  });

  let encodingUsed = '';
  const originalSendCommand = smtpClient.sendCommand.bind(smtpClient);
  
  smtpClient.sendCommand = async (command: string) => {
    if (command.toLowerCase().includes('content-transfer-encoding:')) {
      encodingUsed = command.split(':')[1].trim();
    }
    return originalSendCommand(command);
  };

  await smtpClient.sendMail(email);
  
  console.log('\nFallback encoding test:');
  console.log('Preferred encoding:', 'quoted-printable');
  console.log('Actual encoding used:', encodingUsed);

  await smtpClient.close();
});

tap.test('cleanup test SMTP server', async () => {
  if (testServer) {
    await testServer.stop();
  }
});

export default tap.start();