import { google } from 'googleapis';
import quotedPrintable from 'quoted-printable';
import { getOAuthClient } from '../auth/server.js';
/**
* Create an HTML email template with ScanWave branding
* @param text - Email body text
* @returns HTML email template
*/
export function createEmailTemplate(text: string): string {
return `
${text}
This email has been generated with the help of ScanWave
`;
}
/**
* Send an email through Gmail with QR code
* @param refreshToken - Google refresh token
* @param params - Email parameters (to, subject, text, qr_code)
*/
export async function sendGmail(
refreshToken: string,
{ to, subject, text, qr_code }: { to: string; subject: string; text: string; qr_code: string }
) {
const oauth = getOAuthClient();
oauth.setCredentials({ refresh_token: refreshToken });
const gmail = google.gmail({ version: 'v1', auth: oauth });
const message_html = createEmailTemplate(text);
const boundary = 'BOUNDARY';
const nl = '\r\n'; // RFC-5322 line ending
// Convert HTML to a Buffer, then to latin1 string for quotedPrintable.encode
const htmlBuffer = Buffer.from(message_html, 'utf8');
const htmlLatin1 = htmlBuffer.toString('latin1');
const htmlQP = quotedPrintable.encode(htmlLatin1);
const qrLines = qr_code.replace(/.{1,76}/g, '$&' + nl);
const rawParts = [
'MIME-Version: 1.0',
`To: ${to}`,
`Subject: ${subject}`,
`Content-Type: multipart/related; boundary="${boundary}"`,
'',
`--${boundary}`,
'Content-Type: text/html; charset="UTF-8"',
'Content-Transfer-Encoding: quoted-printable',
'',
htmlQP,
'',
`--${boundary}`,
'Content-Type: image/png',
'Content-Transfer-Encoding: base64',
'Content-ID: ',
'Content-Disposition: inline; filename="qr.png"',
'',
qrLines,
'',
`--${boundary}--`,
''
];
const rawMessage = rawParts.join(nl);
const raw = Buffer.from(rawMessage).toString('base64url');
await gmail.users.messages.send({
userId: 'me',
requestBody: { raw }
});
}