Hello,

I created a trigger that calls a class to count the number of tasks related to an Opportunity, who's Status is "Completed".  The trigger works properly when tasks are inserted, moved to Completed, deleted, or un-deleted.  However, nothing happens if a task is moved from Completed to another status and I would like the count to be decreased when this occurs.  Can anyone help me figure this out?  Thanks,

Trigger:

trigger MainTriggerTask on Task (after insert, after update, after delete, after undelete) {
    
        IF(Trigger.IsInsert){
            
                ClassRenewalTaskCount updater7 = new ClassRenewalTaskCount();
                updater7.taskCountInsert(Trigger.new);
            }
        
        IF(Trigger.IsUpdate){
            
                ClassRenewalTaskCount updater4 = new ClassRenewalTaskCount();
                updater4.taskCountUpdate(Trigger.new,Trigger.old);
        }
        
        IF(Trigger.IsDelete){
            
                ClassRenewalTaskCount updater2 = new ClassRenewalTaskCount();
                updater2.taskCountDel(Trigger.old);
        }

        IF(Trigger.IsUndelete){
            
                ClassRenewalTaskCount updater2 = new ClassRenewalTaskCount();
                updater2.taskCountUpdate(Trigger.new, Trigger.old);
        }
}

Class:

public class ClassRenewalTaskCount {

    Set<ID> OppIds = new Set<ID>();

        String oppPrefix = Opportunity.SObjectType.getDescribe().getKeyPrefix();

    public void taskCountInsert(List<Task> checkTasks) {

        for (Task t : checkTasks) {
                if (t.WhatId != null && t.Status == 'Completed' && t.RP_Prior_60__c <= t.ActivityDate && string.valueof(t.WhatId).startsWith(oppPrefix) ) {
                    OppIds.add(t.WhatId);              
                }
        }

        if (OppIds.size() > 0){

            List<Opportunity> oppsWithTasks = [SELECT Id,RP_Customer_Engagement__c,(SELECT Id FROM Tasks)
                                                FROM Opportunity
                                                WHERE Id IN : OppIds];

                List<Opportunity> oppsUpdatable = new List<Opportunity>();

                    for(Opportunity L : oppsWithTasks){
                        L.RP_Customer_Engagement__c = L.Tasks.size();
                    oppsUpdatable.add(L);
                    }

            if(oppsUpdatable.size()>0){
                update oppsUpdatable;
            }
        }
    }
 
    public void taskCountUpdate(List<Task> checkTasks, List<Task> oldTasks) {

        for (Task t : checkTasks) {
            for (Task prev : oldTasks){
                if (t.WhatId != null && t.Status == 'Completed' && t.RP_Prior_60__c <= t.ActivityDate && string.valueof(t.WhatId).startsWith(oppPrefix) ) {
                    OppIds.add(t.WhatId);              
                }
                if (t.WhatId != null && ((prev.Status == 'Completed' && t.Status <> 'Completed') || t.RP_Prior_60__c > t.ActivityDate) && string.valueof(t.WhatId).startsWith(oppPrefix) ) {
                    OppIds.remove(t.WhatId);
                }
            }
        }

        if (OppIds.size() > 0){

            List<Opportunity> oppsWithTasks = [SELECT Id,RP_Customer_Engagement__c,(SELECT Id FROM Tasks)
                                                FROM Opportunity
                                                WHERE Id IN : OppIds];

                List<Opportunity> oppsUpdatable = new List<Opportunity>();

                    for(Opportunity L : oppsWithTasks){
                        L.RP_Customer_Engagement__c = L.Tasks.size();
                    oppsUpdatable.add(L);
                    }

            if(oppsUpdatable.size()>0){
                update oppsUpdatable;
            }
        }
    }

    public void taskCountDel(List<Task> delTasks) {

            for (Task t2 : delTasks) {
                for (Task prev2 : (List<Task>)Trigger.Old){
                    if (t2.WhatId!= null && (t2.Status == 'Completed' || (prev2.Status == 'Completed' && t2.Status != 'Completed') || t2.RP_Prior_60__c > t2.ActivityDate) && string.valueof(t2.WhatId).startsWith(oppPrefix)){
                        OppIds.add(t2.WhatId);
                    }
                }
            }

        if (OppIds.size() > 0){

            List<Opportunity> oppsWithTasks = [SELECT Id,RP_Customer_Engagement__c,(SELECT Id FROM Tasks)
                                                FROM Opportunity
                                                WHERE Id IN : OppIds];

                List<Opportunity> oppsUpdatable = new List<Opportunity>();

                    for(Opportunity L : oppsWithTasks){
                        L.RP_Customer_Engagement__c = L.Tasks.size();
                    oppsUpdatable.add(L);
                    }

            if(oppsUpdatable.size()>0){
                update oppsUpdatable;
                //update all the leads with activity count
            }
        }
    }
}