public class RequalificationEmailHelper {

    public static void sendEmailsAndGenerateCases(List<Opportunity> records) {
        Map<Id, Opportunity> oppsToCheck = new Map<Id, Opportunity>();

        // fetch the email template Ids
        List<EmailTemplate> requalificationTemplates = new List<EmailTemplate>();
        requalificationTemplates = [Select Id, DeveloperName FROM EmailTemplate WHERE DeveloperName = 'Requalification_Reminder_Email_DE' OR DeveloperName = 'Requalification_Email_DE' OR DeveloperName = 'Requalification_Reminder_Email_FR' OR DeveloperName = 'Requalification_Email_FR' OR DeveloperName = 'Requalification_Reminder_Email_SE' OR DeveloperName = 'Requalification_Email_SE'];
        String requalificationTemplateFR = '';
        String requalificationTemplateDE = '';
        String requalificationTemplateSE = '';
        String requalificationReminderTemplateFR = '';
        String requalificationReminderTemplateDE = '';
        String requalificationReminderTemplateSE = '';
        for(EmailTemplate template : requalificationTemplates){
            if(template.DeveloperName == 'Requalification_Email_FR')
                requalificationTemplateFR = template.Id;
            else if (template.DeveloperName == 'Requalification_Email_DE')
                requalificationTemplateDE = template.Id;
            else if (template.DeveloperName == 'Requalification_Email_SE')
                requalificationTemplateSE = template.Id;
            else if (template.DeveloperName == 'Requalification_Reminder_Email_FR')
                requalificationReminderTemplateFR = template.Id;
            else if (template.DeveloperName == 'Requalification_Reminder_Email_DE')
                requalificationReminderTemplateDE = template.Id;
            else if (template.DeveloperName == 'Requalification_Reminder_Email_SE')
                requalificationReminderTemplateSE = template.Id;
        }
        // end - fetch email template ids

        for (Opportunity o : records) {
            oppsToCheck.put(o.id, o);
        }

        Boolean isonsandbox = runningInASandbox();
        Map<Opportunity, String> oppsToSendEmailsWith = new Map<Opportunity, String>();
        List<Opportunity> oppsToCreateCasesOn = new List<Opportunity>();


        for (Opportunity o : oppsToCheck.values()) {
            Integer daysBetween = (o.bookingDate__c).daysBetween(o.MovingoutDate__c);
            Integer daysFromToday = (System.today()).daysBetween(o.MovingoutDate__c);
            if (daysBetween > 21) {
                //check if email was sent
                if (o.Requal_Email_Sent_On__c != null) {
                    //check if response was received - if it was nothing happens
                    if (o.Requal_Email_Response_received__c) {
                        //stop
                    } else {
                        if (daysFromToday == 17) {
                            //send email again
                            oppsToSendEmailsWith.put(o, 'reminder');
                        }
                        if (daysFromToday == 15) {
                            //create case
                            oppsToCreateCasesOn.add(o);
                        }
                    }
                } else {
                    //send an email since it wasnt send already - 21 days before the move
                    if(daysFromToday == 21)
                       oppsToSendEmailsWith.put(o, 'requal');
                }
            } else if (daysBetween <= 21 && daysbetween >= 17) {
                //check if email was sent
                if (o.Requal_Email_Sent_On__c != null) {
                    //check if response was received - if it was nothing happens
                    if (o.Requal_Email_Response_received__c) {
                        //stop
                    } else {
                        if (daysFromToday == 14) {
                            //create case
                            oppsToCreateCasesOn.add(o);
                        }
                    }
                } else {
                    //send an email since it wasnt send already- 16 days before the move
                    if(daysFromToday == 16)
                        oppsToSendEmailsWith.put(o, 'requal');
                }
            } else if (daysBetween < 17) {
                //check if email was sent
                if (o.Requal_Email_Sent_On__c != null) {
                    //check if response was received - if it was nothing happens
                    if (o.Requal_Email_Response_received__c) {
                        //stop
                    } else {
                        if ((Date.valueOf(o.Requal_Email_Sent_On__c)).daysBetween(system.today()) == 2) {
                            //create case
                            oppsToCreateCasesOn.add(o);
                        }
                    }
                } else {
                    //send an email since it wasnt send already - 1 day after booking
                    if((o.BookingDate__c).daysBetween(system.today()) == 1)
                        oppsToSendEmailsWith.put(o, 'requal');
                }
            }
        }


        //method to send emails and update last email sent field on opportunities
        if (oppsToSendEmailsWith.size() > 0) {
            List<Messaging.SingleEmailMessage> mails = new List<Messaging.SingleEmailMessage>();
            OrgWideEmailAddress[] owea;
            owea = [select Id, Address from OrgWideEmailAddress where Address = 'service@movinga.de' OR Address = 'service.client@movinga.fr' OR Address = 'service@movinga.se'];
            List<Opportunity> oppsToUpdate = new List<Opportunity>();

            for (Opportunity opp : oppsToSendEmailsWith.keySet()) {
                Messaging.SingleEmailMessage mail = new Messaging.SingleEmailMessage();
                mail.setTargetObjectId(opp.PersonContactIdAuto__c);
                mail.setWhatId(opp.Id);
                mail.setToAddresses(new List<String>{opp.email__c});
                mail.setSaveAsActivity(true);

                opp.LastRESTUpdate__c = System.now().addYears(-10);

                if (opp.RecordTypeName__c == 'DE Opportunity' || opp.RecordTypeName__c == 'DE Baggage Opportunity') {
                    mail.setReplyTo('service@movinga.de');
                    //mail.setTemplateId(requalificationTemplateDE);
                    if (owea.get(0).Address == 'service@movinga.de') {
                        mail.setOrgWideEmailAddressId(owea.get(0).Id);
                    } else if (owea.get(1).Address == 'service@movinga.de') {
                        mail.setOrgWideEmailAddressId(owea.get(1).Id);
                    } else if (owea.get(2).Address == 'service@movinga.de') {
                        mail.setOrgWideEmailAddressId(owea.get(2).Id);
                    }

                } else if (opp.RecordTypeName__c == 'FR Opportunity' || opp.RecordTypeName__c == 'FR Baggage Opportunity' || opp.RecordTypeName__c == 'White Label') {
                    mail.setReplyTo('service.client@movinga.fr');
                    //mail.setTemplateId(requalificationTemplateFR);
                    if (owea.get(0).Address == 'service.client@movinga.fr') {
                        mail.setOrgWideEmailAddressId(owea.get(0).Id);
                    } else if (owea.get(1).Address == 'service.client@movinga.fr') {
                        mail.setOrgWideEmailAddressId(owea.get(1).Id);
                    } else if (owea.get(2).Address == 'service.client@movinga.fr') {
                        mail.setOrgWideEmailAddressId(owea.get(2).Id);
                    }

                } else if (opp.RecordTypeName__c == 'SE Opportunity') {
                    mail.setReplyTo('service@movinga.se');
                    if (owea.get(0).Address == 'service@movinga.se') {
                        mail.setOrgWideEmailAddressId(owea.get(0).Id);
                    } else if (owea.get(1).Address == 'service@movinga.se') {
                        mail.setOrgWideEmailAddressId(owea.get(1).Id);
                    } else if (owea.get(2).Address == 'service@movinga.se') {
                        mail.setOrgWideEmailAddressId(owea.get(2).Id);
                    }
                }
                else continue;


                if (opp.RecordTypeName__c == 'DE Opportunity' || opp.RecordTypeName__c == 'DE Baggage Opportunity'){
                    if (oppsToSendEmailsWith.get(opp) == 'requal') mail.setTemplateId(requalificationTemplateDE);
                    else mail.setTemplateId(requalificationReminderTemplateDE);
                }
                else if(opp.RecordTypeName__c == 'FR Opportunity' || opp.RecordTypeName__c == 'FR Baggage Opportunity' || opp.RecordTypeName__c == 'White Label'){
                    if (oppsToSendEmailsWith.get(opp) == 'requal') mail.setTemplateId(requalificationTemplateFR);
                    else mail.setTemplateId(requalificationReminderTemplateFR);
                }
                else if(opp.RecordTypeName__c == 'SE Opportunity'){
                    if (oppsToSendEmailsWith.get(opp) == 'requal') mail.setTemplateId(requalificationTemplateSE);
                    else mail.setTemplateId(requalificationReminderTemplateSE);
                }
                Opportunity oppty = new Opportunity();
                oppty.id = opp.id;
                oppty.Requal_Email_Sent_On__c = System.now();
                oppty.Skip_Validation_New__c = Decimal.valueOf(String.valueOf(System.now()).replace('-','').replace(':','').replace(' ',''));
                oppsToUpdate.add(oppty);

                mails.add(mail);
            }

            try {
                Messaging.sendEmail(mails);
                update oppsToUpdate;
            } catch (Exception e) {
                System.debug('Error happened while sending emails/updating opportunities: ' + e.getMessage());
            }
        }

        //method to create cases
        if (oppsToCreateCasesOn.size() > 0) {
            List<Case> casesToInsert = new List<Case>();
            //Fetching the assignment rules on case
            AssignmentRule AR = new AssignmentRule();
            AR = [select id from AssignmentRule where SobjectType = 'Case' and Active = true limit 1];

            //Creating the DMLOptions for "Assign using active assignment rules" checkbox
            Database.DMLOptions dmlOpts = new Database.DMLOptions();
            dmlOpts.assignmentRuleHeader.assignmentRuleId= AR.id;

            for (Opportunity opp : oppsToCreateCasesOn) {
                Case c = new Case();
                c.Opportunity__c = opp.id;
                c.Issue_Category_1__c = 'Before move';
                c.Issue_Category_2__c = 'Order Validation';
                c.Subject = 'Requalification';
                //Setting the DMLOption on Case instance
                c.setOptions(dmlOpts);
                if (opp.RecordTypeName__c == 'DE Opportunity' || opp.RecordTypeName__c == 'DE Baggage Opportunity')
                    c.Origin = 'DACH Customer Service';
                else if (opp.RecordTypeName__c == 'FR Opportunity' || opp.RecordTypeName__c == 'FR Baggage Opportunity' || opp.RecordTypeName__c == 'White Label')
                    c.Origin = 'FR Customer Service';
                else if (opp.RecordTypeName__c == 'SE Opportunity')
                    c.Origin = 'SE Customer Service';
                else continue;

                casesToInsert.add(c);
            }

            if (casesToInsert.size() > 0) {
                insert casesToInsert;
            }
        }

    }

    public static Boolean runningInASandbox() {
        return [SELECT Id, IsSandbox FROM Organization LIMIT 1].IsSandbox;
    }

}