Custom Lead conversion with custom Convet Button

// Code is for Custom lead conversion through custom lead convert button in Account,Contact,Opportunity

 

{!REQUIRESCRIPT("/soap/ajax/37.0/connection.js")} 
{!REQUIRESCRIPT("/soap/ajax/37.0/apex.js")} 

var accnt = new sforce.SObject("Account"); 
var insertedaccountid =""; 
if({!Enquiry__c.Lead_Converted__c} == 1) 
{ 
alert('Lead is already converted'); 
} 
else 
{ 
accnt.Name='{!Enquiry__c.Company_Name__c}'; 
if(accnt.Name !="") 
{ 
var p = new sforce.SObject('Enquiry__c'); 
p.id = "{!Enquiry__c.Id}"; 
p.Lead_Converted__c = 1; 
// p.Enquiry_Status__c = 'Converted'; 
var result = sforce.connection.update([p]); 

accnt.Id = '{!Account.Id}'; 
accnt.Name = '{!Enquiry__c.Company_Name__c}'; 
accnt.OwnerId='{!Enquiry__c.OwnerId}'; 
accnt.BillingStreet='{!Enquiry__c.Billing_Street__c}'; 
accnt.BillingCity='{!Enquiry__c.Billing_City__c}'; 
accnt.BillingPostalCode='{!Enquiry__c.Billing_Zip_Postal_Code__c}'; 
accnt.BillingState='{!Enquiry__c.Billing_State_Province__c}'; 
accnt.BillingCountry='{!Enquiry__c.Billing_Country__c}'; 
var result2 = sforce.connection.create([accnt]); 
//alert(result2[0].id); 
insertedaccountid= result2[0].id; 

var cnt= new sforce.SObject("Contact"); 
cnt.Id = '{!Contact.Id}'; 
cnt.OwnerId='{!Enquiry__c.OwnerId}'; 
cnt.AccountId=result2[0].id; 
cnt.lastName = '{!Enquiry__c.Name}'; 
cnt.MailingStreet=accnt.BillingStreet; 
cnt.MailingCity=accnt.BillingCity; 
cnt.MailingPostalCode=accnt.BillingPostalCode; 
cnt.MailingState=accnt.BillingState; 
cnt.MailingCountry=accnt.BillingCountry; 
var result = sforce.connection.create([cnt]); 

var opt= new sforce.SObject("Opportunity__c"); 
var suffixToAdd = "-CRM Implimentation"; 
opt.Id = '{!Opportunity__c.Id}'; 
opt.OwnerId='{!Enquiry__c.OwnerId}'; 
opt.Account__c= cnt.AccountId; 
opt.Name = '{!Enquiry__c.Company_Name__c}'+ suffixToAdd; 
var result = sforce.connection.create([opt]); 

if(result[0].getBoolean("success")) 
{ 
var urlis ="/"+insertedaccountid; 
//alert(urlis); 

window.location = urlis; 
} 
else 
{ 
alert('Error : '+result); 
} 
} 
}