Add EPC QR code to make bank transactions easier (#61)

See https://de.wikipedia.org/wiki/EPC-QR-Code#EPC-QR-Code_f%C3%BCr_%C3%9Cberweisung_erstellen for more information about the EPC coding

Co-authored-by: dusker <dusker@gmx.de>
Reviewed-on: #61
Co-authored-by: dusker <jens.graef+ezgg@posteo.de>
Co-committed-by: dusker <jens.graef+ezgg@posteo.de>

src/ezgg_lan_manager/pages/Account.py

@@ -1,7 +1,7 @@
 from decimal import Decimal
 from typing import Optional
 
-from rio import Column, Component, event, Text, TextStyle, Button, Color, Revealer, Row, ProgressCircle, Link
+from rio import Column, Component, event, Text, TextStyle, Button, Color, Revealer, Row, ProgressCircle, Link, Image
 
 from src.ezgg_lan_manager import ConfigurationService, UserService, AccountingService
 from src.ezgg_lan_manager.components.MainViewContentBox import MainViewContentBox
@@ -14,6 +14,7 @@ class AccountPage(Component):
     user: Optional[User] = None
     balance: Optional[Decimal] = None
     transaction_history: list[Transaction] = list()
+    payment_qr_image: bytes = None
     banking_info_revealer_open: bool = False
     paypal_info_revealer_open: bool = False
 
@@ -28,6 +29,11 @@ class AccountPage(Component):
             self.user = await self.session[UserService].get_user(user_id)
             self.balance = await self.session[AccountingService].get_balance(user_id)
             self.transaction_history = await self.session[AccountingService].get_transaction_history(user_id)
+            self.payment_qr_image = self.session[AccountingService].make_payment_qr_image(
+                    "Einfach Zocken Gaming Gesellschaft",
+                    "GENODE51BIK",
+                    "DE47517624340019856607",
+                    f"AUFLADUNG - {self.user.user_id} - {self.user.user_name}")
 
     async def _on_banking_info_press(self) -> None:
         self.banking_info_revealer_open = not self.banking_info_revealer_open
@@ -36,7 +42,7 @@ class AccountPage(Component):
         self.paypal_info_revealer_open = not self.paypal_info_revealer_open
 
     def build(self) -> Component:
-        if not self.user and not self.balance:
+        if not self.user or not self.payment_qr_image:
             return Column(
                 MainViewContentBox(
                     ProgressCircle(
@@ -85,6 +91,10 @@ class AccountPage(Component):
                     margin=0,
                     margin_bottom=1,
                     align_x=0.5
+                ),
+                Image(self.payment_qr_image,
+                      min_width=20,
+                      min_height=20
                 )
             ),
             margin=2,

src/ezgg_lan_manager/services/AccountingService.py

@@ -1,4 +1,6 @@
+import io
 import logging
+import qrcode
 from collections.abc import Callable
 from datetime import datetime
 from decimal import Decimal, ROUND_DOWN
@@ -74,3 +76,29 @@ class AccountingService:
             return "0.00 €"
         rounded_decimal = str(euros.quantize(Decimal(".01"), rounding=ROUND_DOWN))
         return f"{rounded_decimal} €"
+
+    @staticmethod
+    def make_payment_qr_image(beneficiary_name, beneficiary_bic, beneficiary_iban, text, amount_euros=None) -> bytes:
+        text = text.replace("\n",";")
+        amount_formatted = "EUR{:.2f}".format(amount_euros) if amount_euros else ""
+        epc_text = f"""BCD
+002
+1
+SCT
+{beneficiary_bic}
+{beneficiary_name}
+{beneficiary_iban}
+{amount_formatted}
+
+
+{text}
+"""
+        qr = qrcode.QRCode(
+            version=6,
+            error_correction=qrcode.constants.ERROR_CORRECT_M,
+        )
+        qr.add_data(epc_text)
+        img = qr.make_image()
+        img_bytes = io.BytesIO()
+        img.save(img_bytes)
+        return img_bytes.getvalue()