workflow rule to alert when someone hasn't logged in after x amount of days

global class BatchtoSendEmailstoUser implements Database.Batchable<sobject>{
    Date tdate = System.today() - 37;  
    Map<Id,Profile> profileIds = new Map<id,profile>([SELECT Id,UserLicenseId FROM Profile where UserLicenseId  in (SELECT Id FROM UserLicense where name ='Salesforce')]);
    List<User> userIds = [SELECT Id FROM User WHERE profileId in:profileIds.Keyset() AND IsActive=True AND LastLoginDate = :tdate];
    
    public String query = 'SELECT Id FROM User WHERE Id IN :userIds';
    
    global Database.QueryLocator start(Database.BatchableContext bc){
        return Database.getQueryLocator(query);
    }
    
    global void execute(Database.BatchableContext bc, LIST<sobject> InactiveUsers) {
        
        EmailTemplate emailTemplate = [select Id, Body  from EmailTemplate where DeveloperName = 'Freeze_warning_to_Users'];
        for(Sobject user:InactiveUsers){
            User user2 = (User)user;
            Messaging.SingleEmailMessage email = new Messaging.SingleEmailMessage();
            email.setToAddresses(new String[] {user2.Email});
            email.setSaveAsActivity(false);
            email.setTargetObjectId(user2.Id);
            email.setTemplateId(emailTemplate.Id);
            email.setWhatId(user2.Id);
            Messaging.sendEmail(new Messaging.SingleEmailMessage[] {email});            
        }        
    }
    
    global void finish(Database.BatchableContext FreezeWarningtoUsers) {}
    
}