Coding in PHP MVC Framework

Need to do custom coding in vTiger CRM which works in PHP MVC Framework. Will mention all the requirements here: 1. Need “create sales order” button within contact details page which will auto fill contact fields such as “contact name” , “contact number “, “contact address” in sales order details page 2. Need “create invoice button” within sales order details page which will auto fill contact (“name” and “number”) and order related fields (“sales order subject” ,”Invoice Date” should be “Pickup Date” of sales order and “Due Date” should be ”Delivery Date” of sales order ) in the invoice. We also need “View invoice” button if invoice is already raised against the sales order. This should load vtiger’s invoice detail page which has features to edit individual field in view mode as well. 3. Sales Order Module - While creating a sales order, we don’t want to add any product in the Sales Order initially. We want by default Dummy Product in the Order and this Dummy Product will be changed later on by editing the sales order before creating an invoice. 4. Regarding Invoice -We enter products in Sales Order and click on Generate Invoice. Then, the order items (products) should be reflected in Invoice. 5. We want to incorporate Discount Coupon Code functionality. While creating/editing an Order, we should select a Coupon code and the corresponding discount(in % or absolute value) should be applied automatically. The agents or vendors should not be able to give discount manually. 6. Invoice Module - Printing multiple Invoice. In Invoice listing module We select invoices based on Due Date(or Delivery Date) and then print all the invoices. So we want a Print button here which will print all the invoices which are present in the list. 7. Sales order status can be made as “Invoice created” , “Out for delivery” ,“Delivered” only if an invoice is created against the sales order. Need to built in this validation 8. Within contact details page we need listing of all past orders placed by that contact in order history section 9 We should be able to click an order from order history section of contact module to go to corresponding order details page 10. In case first order is created for a contact the ” order type” should be “New”. For subsequent orders order type should be “Repeat”. This should be filled automatically while creating an order by maintaining count of orders pre contact. 11. Need changes in vTiger’s invoice PDF format or create a new custom PDF.