public without sharing class TR001_EmailMessage {

    /**
    * @description Process to detect if there is a spam from a custom, creating loads and loads of cases.
    * @param emailsList List of email
    */
    public static void DetectCreationFromSpam (Map<ID, EmailMessage> emailsList) {
        system.debug('### START TR002_EmailMessage : DetectCreationFromSpam');

        try {
            // Email Blacklist
            List<EMAILBLACKLIST__c> emailsBlacklist = EMAILBLACKLIST__c.getAll().Values();

            if(!emailsList.isEmpty() ){
                // For all emails in list, compare Email address and Subject with the custom settings
                for (EmailMessage newEmail : emailsList.values()) {
                    system.debug('## Email FROM: ' + newEmail.FromAddress);
                    system.debug('## Case ID: '+newEmail.ParentId);
                    for(EMAILBLACKLIST__c emailBlacklist : emailsBlacklist) {
                        if(emailBlacklist.Name.containsIgnoreCase(newEmail.FromAddress) && String.isBlank(newEmail.Subject)){
                            newEmail.addError('## ERROR : Spam Email :\n '+newEmail);
                        }
                        if(emailBlacklist.Name.containsIgnoreCase(newEmail.FromAddress) && emailBlacklist.SUBJECT__c.containsIgnoreCase(newEmail.Subject)){
                            newEmail.addError('## ERROR : Spam Email :\n '+newEmail);
                        }
                    }
                }
            }
            system.debug('### END TR002_EmailMessage : DetectCreationFromSpam');
        }  catch (Exception e) {
            system.debug('ERROR # Detect Email Spam (' + e + ') Line : ' + String.valueOf(e.getLineNumber()) + ' !');
            throw e;
        }
    }
}