Hello, we have the following button that creates a new case record automatically, the problem is this doesn't take into account required fields on the case and completely bypasses the requirement:

{!REQUIRESCRIPT("/soap/ajax/29.0/connection.js")} 

// Save url 
var url = parent.location.href; 

var bug = new sforce.SObject('Case'); 

bug.RecordTypeId='012U0000000Qqxb'; 
bug.ParentId='{!Case.Id}'; 
bug.Service_Product__c='{!Case.Service_Product__c}'; 
bug.Product_Version__c='{!Case.Product_Version__c}'; 
bug.OwnerId='00GU0000001gEO8'; 
bug.SR__c='{!Case.SR__c}'; 
bug.ES__c='{!Case.ES__c}'; 
bug.Subject='{!Case.Service_Product__c}'+ ' ' + '{!Case.Product_Version__c}' + ' - ' +'Doc Defect' 


var result = sforce.connection.create([bug]); 


// Process result, if success refresh page 
if( result[0].getBoolean("success") ){ 
window.location.href = 'https://calabrio.my.salesforce.com'+'/' + result[0].id; 

} 
else { 
log("Failed to update project: " + result[0]); 
}

Based on other questions asked in the community, I've come up with the following, adding the required fields into if statements, but it still doesn't work:

{!REQUIRESCRIPT("/soap/ajax/29.0/connection.js")} 


/*Required fields*/ 
var DocTitle = '{!Case.Book_Title__c}'; 
var SectionTitle = '{!Case.Section_Title__c}'; 
var Description = '{!Case.Description}'; 


/*Field requirements*/ 
if(DocTitle == ''){ 
alert('The Doc Title field is required.') 
} 

ifSectionTitle == ''){ 
alert('The Section Title field is required.'); 
} 

if(Description == ''){ 
alert('The Description field is required.') 
} 


/*Once required fields are filled in*/ 
else{ 
// Save url 
var url = parent.location.href; 

var bug = new sforce.SObject('Case'); 

bug.RecordTypeId='012U0000000Qqxb'; 
bug.ParentId='{!Case.Id}'; 
bug.Service_Product__c='{!Case.Service_Product__c}'; 
bug.Product_Version__c='{!Case.Product_Version__c}'; 
bug.OwnerId='00GU0000001gEO8'; 
bug.SR__c='{!Case.SR__c}'; 
bug.ES__c='{!Case.ES__c}'; 
bug.Subject='{!Case.Service_Product__c}'+ ' ' + '{!Case.Product_Version__c}' + ' - ' +'Doc Defect' 


var result = sforce.connection.create([bug]); 


// Process result, if success refresh page 
if( result[0].getBoolean("success") ){ 
window.location.href = 'https://calabrio.my.salesforce.com'+'/' + result[0].id; 

} 
else { 
log("Failed to update project: " + result[0]); 
} 
}

I receive the error "A problem with the OnClick JavaScript for this button or link was encountered: Unexpected token )" Any ideas? Thanks in advance!