Document Creation in SharePoint 2013. P.S more info in the description

Platform: SharePoint 2013 / SharePoint Hosted App SP-lists: documents (SP document library) Additional fields to be included in the list : Customer number (text) Invoice number (text) Street (text) Postal code (text) Location (text) Additive (Text) Country (text) Invoice date (date) Creating a SharePoint-hosted app that will automatically generate an invoice (Word document). Use a surface as a page (eg. In [login to view URL]) to fill the invoice. By pressing a button that will be on the [login to view URL] page the invoice document should be created. For the Document Library a Word template Should be used. The template is created only once and used for each new document. You can link the (above fields) with the Template, so that each new document automatically gets the appropriate values (metadata). In addition, create a list (list view) of all documents. OPTIONAL: You can voluntarily assume the position data of an invoice (for example in the form of a table) in the document. For this, you can either transfer the table in the form of rich text or use other options. Create a small Document for the usage of it. and also mention proper comments in the code for the understanding purpose