Upon opportunity creation add the opportunity owner's manager as an opportunity team member with role 'Sales Manager' If the opportunity owner is a manager, add one of their direct employees as a 'Sales Rep' opportunity team member

OwnerManagerTrigger

/*
Upon opportunity creation add the opportunity owner's manager as an opportunity team member with role 'Sales Manager'

If the opportunity owner is a manager, add one of their direct employees as a 'Sales Rep' opportunity team member
 */

trigger OwnerManager on Opportunity (after insert) {
	
    for(Opportunity opp : Trigger.new){
        //Get opp owner manager info
        Opportunity oppWithManagerInfo = [SELECT Id,
                                                 Owner.ManagerId
                                            FROM Opportunity
                                           WHERE Id = :opp.Id];
        
        //Prep a list of team members for later insert
        List<OpportunityTeamMember> otms = new List<OpportunityTeamMember>();
            
        //Create the opportunity team member role
        if(oppWithManagerInfo.Owner.ManagerId != null) {
            OpportunityTeamMember otm = new OpportunityTeamMember();
            otm.UserId 				  = oppWithManagerInfo.Owner.ManagerId;
            otm.OpportunityId 		  = opp.Id;
            otm.TeamMemberRole  	  = 'Sales Manager';
            otms.add(otm);
            //insert otm;
        }
            
         //Check is owner is a manager 
         List<User> reportees = [SELECT Id
                                   FROM User
                                  WHERE ManagerId = :opp.OwnerId
                                   ];
            
         //Create the member for the reportee
          if(!reportees.isEmpty()){
              OpportunityTeamMember reporteeMember = new OpportunityTeamMember();
              reporteeMember.UserId 		= reportees.get(0).Id;
              reporteeMember.OpportunityId 	= opp.Id;
              reporteeMember.TeamMemberRole = 'Sales Rep';
              otms.add(reporteeMember);
              //insert reporteeMember;
   
            }
            
          //Insert all members at once
            if(!otms.isEmpty()){
               insert otms;
           }  
        } 
    }
    
    
  //Test Class
  
  @isTest
private class OwnerManagerTest {
	
    @isTest static void ownerHasNoManager(){
        //Populate fields for a user
        User myUser = new User();
        myUser.FirstName = 'Matt';
        myUser.LastName  = 'Lacey';
        myUser.Email = 'mlacey@trello.com';
        myUser.UserName = 'mlacey@trello.com';
        myUser.Alias = 'mlacey';
        myUser.ProfileId = [SELECT Id
                             FROM Profile
                            WHERE Name = 'System Administrator'].Id;
        myUser.TimeZoneSidKey = 'America/Denver';
        myUser.LocaleSidKey = 'en_US';
        myUser.EmailEncodingKey = 'UTF-8';
        myUser.LanguageLocaleKey = 'en_US';
        myUser.ManagerId = null;
        insert myUser;
        
        Opportunity opp = new Opportunity();
        opp.Name = 'Trello';
        opp.Amount = 100;
        opp.StageName = 'Prospecting';
        opp.CloseDate = Date.today();
        opp.OwnerId = myUser.Id;
        insert opp;
        
        List<OpportunityTeamMember> otms = [SELECT Id 
                                             FROM OpportunityTeamMember
                                            WHERE OpportunityId = :opp.Id];
        
        System.assertEquals(0, otms.size());
    }
    
    @isTest static void ownerHasManager(){
        //Create a manager
        User manager = new User();
        manager.FirstName = 'Matt';
        manager.LastName  = 'Lacey';
        manager.Email = 'mlacey@trello.com';
        manager.UserName = 'mlacey@trello.com';
        manager.Alias = 'mlacey';
        manager.ProfileId = [SELECT Id
                             FROM Profile
                            WHERE Name = 'System Administrator'].Id;
        manager.TimeZoneSidKey = 'America/Denver';
        manager.LocaleSidKey = 'en_US';
        manager.EmailEncodingKey = 'UTF-8';
        manager.LanguageLocaleKey = 'en_US';
        manager.ManagerId = null;
        insert manager;
        
        User me = [SELECT Id
                     FROM User
                    WHERE Id = :UserInfo.getUserId()];
        me.ManagerId = manager.Id;
        update me;
        
        Opportunity opp = new Opportunity();
        opp.Name = 'New Trello Deal';
        opp.Amount = 100;
        opp.StageName = 'Prospecting';
        opp.CloseDate = Date.today();
        opp.OwnerId = me.Id;
        insert opp;
        
        List<OpportunityTeamMember> otms = [SELECT Id
                                              FROM OpportunityTeamMember
                                             WHERE OpportunityId = :opp.Id
                                               AND UserId = :manager.Id
                                               AND TeamMemberRole = 'Sales Manager'];
        
        System.assertEquals(1, otms.size());        
        
    }
    
    @isTest static void ownerIsManager(){
        //Create a reportee with me as manager
        User reportee = new User();
        reportee.FirstName = 'Mike';
        reportee.LastName  = 'Angelo';
        reportee.Email = 'mangelo@trello.com';
        reportee.UserName = 'mangelo@trello.com';
        reportee.Alias = 'mangelo';
        reportee.ProfileId = [SELECT Id
                                FROM Profile
                               WHERE Name = 'System Administrator'].Id;
        reportee.TimeZoneSidKey = 'America/Denver';
        reportee.LocaleSidKey = 'en_US';
        reportee.EmailEncodingKey = 'UTF-8';
        reportee.LanguageLocaleKey = 'en_US';
        reportee.ManagerId = UserInfo.getUserId();
        insert reportee;
        
        //Create an opp under me
        Opportunity opp = new Opportunity();
        opp.Name = 'Trello Deal 2';
        opp.Amount = 200;
        opp.StageName = 'Prospecting';
        opp.CloseDate = Date.today();
        opp.OwnerId = UserInfo.getUserId();
        insert opp;
        
        List<OpportunityTeamMember> otms = [SELECT Id, UserId
                                              FROM OpportunityTeamMember
                                             WHERE OpportunityId  = :opp.Id
                                               //AND UserId		  = :reportee.Id
                                               AND TeamMemberRole = 'Sales Rep'];
        
        System.debug('Opp OwnerId ' + opp.OwnerId );
        System.debug('Reportee manager Id ' + reportee.ManagerId );
        System.debug('otms ' + otms.get(0).UserId);
        System.assertEquals(1, otms.size());
    }
}