Day Books mappings and virtuemart-joomla

I am stuck with a custom request, i need to create a DayBook. Can this be done via API? what method should i use from API?

1. e-conomic day book type: Manual customer

VM                                  - EConomic
invoice number from VM - Entry e-conomic
invoice date VM - date
customer number - customer
total+vat - amount
motkonto - {static_value}
mva- {static_value}
economic text - {static_text}

Invoice date - Due date
invoice number from VM - invoice number

2. Is it possible to upload invoice PDF from the VM (last time I checked it culd not), or in any other way make the pdf document available in e-conomic via link or something?