NimEric German Tax Upload

nimeric.nim

## Nimeric
##
## This is a proof-of-concept to link to the official german tax upload, that is
## distributed as a proprietary cross platform C library with headers called "eric".
##
## Obtaining these files requires a free developer account at elster.de developer area.
## To actually use them, a vendor ID needs to be applied for on the same site.
## 
## This requires placing the libericapi.so and other library files "liberic/lib" sub-directory, and placing
## the headers in the liberic/headers sub-directory.
##

import strutils

import futhark

# Tell futhark where to find the C libraries you will compile with, and what
# header files you wish to import.
importc:
  path "liberic/include"
  "ericapi.h"

# Tell Nim how to compile against the library. If you have a dynamic library
# this would simply be a `--passL:"-l<library name>`
{.passL: "-L./liberic/lib -lericapi".}

var cert: EricZertifikatHandle
var pinInfo: ptr uint32

var pluginPathL = cstring"liberic/lib/plugins2/"
let pluginPath = cast[ptr byteChar](pluginPathL)
var logPathL = cstring"."
let logPath = cast[ptr byteChar](logPathL)
var certPathL = cstring"test-softidnr-pse.pfx"
let certPath = cast[ptr byteChar](certPathL)
var pinL = cstring"123456"
let pin = cast[ptr byteChar](pinL)
var pdfPathL = cstring"./test.pdf"
let pdfPath = cast[ptr byteChar](pdfPathL)

var r:cint

r = EricInitialisiere(pluginPath, logPath)
if r != 0:
  raise newException(IOError, "EricInitialisiere: Error $1" % $r)

r = EricGetHandleToCertificate(cert.addr, pinInfo, certPath)
if r != 0:
  raise newException(IOError, "EricGetHandleToCertificate: Error $1" % $r)

var response = EricRueckgabePufferErzeugen()
var status = EricRueckgabePufferErzeugen()
var certXml = EricRueckgabePufferErzeugen()
var printParams = ericDruckParameterT(
  version: 2.cuint,
  vorschau: 1.cuint,
  ersteSeite: 0.cuint,
  duplexDruck: 0.cuint,
  pdfName: pdfPath,
  fussText: nil
)

r = Ericholezertifikateigenschaften(cert, pin, certXml)
if r != 0:
  raise newException(IOError, "Ericholezertifikateigenschaften: Error $1" % $r)

const dataVersion = "ESt_2020"
const dataBuffer = readFile("ESt_2020.xml")

r = EricBearbeiteVorgang(dataBuffer,dataVersion,ERIC_DRUCKE.cuint,printParams.addr,nil,nil,response,status)
r = EricCloseHandleToCertificate(cert)
if r != 0:
  raise newException(IOError, "EricCloseHandleToCertificate: Error $1" % $r)

r = EricBeende()
if r != 0:
  raise newException(IOError, "EricBeende: Error $1" % $r)