/* Notes:
Async/Sync
For the sake of simplicity, we aren't going to use Promises or callback
functions, but assume their implementation.
*/
create(request, response) {
    // Authentication: session exists
    let auth_user = redis.get(request.get('X-Session-Token'));
    if (auth_user === undefined) {
        response.status(401).json({});
    }

    // User group / role permissions
    auth_user = Models.users.find(auth_user.id);
    if (auth_user.permissions('can_create_users') !== true) {
        response.status(403).json({});
    }

    // Input validation and sanitization
    let errors = [];
    if (request.query.type !== 'admin' || request.query.type !== 'poweruser') {
        errors.push('invalid type: admin or poweruser requestuired');
    }
    if (!request.body.name) {
        errors.push('name requestuired');
    }
    if (!request.body.email || !validator.is_email(request.body.email)) {
        errors.push('email requestuired');
    }
    if (!request.body.phone || !validator.is_phone(request.body.phone)) {
        errors.push('phone requestuired');
    }
    if (errors.length) {
        response.status(400).json({});
    }

    // Create User
    let password = library.generate_password();
    let created_user = Models.user.create({
        name: request.body.name,
        email: request.body.email,
        phone: request.body.phone,
        password: password,
        created_by: auth_user.id
    });

    response.status(200).json({
        user: {}
    });

    // Async non-blocking actions
    // Send new user email
    emails.send('user_created', {
        email: request.body.email
    });
    // Alert sales team of new user creation
    emails.send('internal_user_created', {
        url: 'fake-url-to-new-user-page'
    });
    // Alert sales team via Slack
    slack.new_user_added({
        url: 'fake-url-to-new-user-page'
    });
    // Add new user to SalesForce
    salesforce.add_user({
        name: request.body.name,
        email: request.body.email,
        phone: request.body.phone
    });
    // Send user their password via SMS
    sms.send_password({
        phone: request.body.phone,
        password: password
    });
}