build a payment gateway module for Magento 2

Hi all, We need to create a module to connect a magento 2 store to our payment gateway. All communication with the gateway is done using SSL encryption and no confidential cardholder data is ever stored on the Magento 2 website. A process called tokenization is used to run transactions with stored payment information. This lets the customers pay with a 'saved' card which are not stored on the magento 2 server at all. When a customer visits the store and make checkout, he needs to select the payment method at the checkout, while selection of the payment gateway, he will need to enter the credit card information. He will be able to save the credit card to make further transaction easy and fast. So next time when he comes for the purchase, he will just need to select saved credit card. Customer will be able to add, edit and remove the credit cards from the my account section, and the same feature is available in the admin section for the admin of the website. Stored payment method and Token will be stored in the Magento vault. Logged in customers with stored credit card will be able to complete purchase with magento "instant purchase" button (one click checkout). The Extension should include: Pay by credit card Capture and authorize Payment facility Process and manage the transaction easily and securely Sending line items with transactions CCV Validation (on first transaction or with every purchase) Saved cards via tokenization for simple future checkouts and for “instant purchase” client-side encryption and transparent redirect No single-transaction limits Manage saved payment data for each customer Edit orders and reorder without contacting the customer for their CC info. Magento SOAP API support Stored credit card management—customers can add and delete returned data from server on successful transaction should be logged with the order. failed transaction info should be emailed to admin with magento “payment failed email” support for installment payments. 100% Open source code Thanks.