Replace float with Decimal for price calculations

Fix Decimal precision issue

Fix Decimal precision issue

Fix Decimal precision issue

Fix old prices for tickets

Fix Decimal precision issue

testing/unittests/AccountingServiceTests.py

@@ -1,6 +1,7 @@
 import unittest
 from datetime import datetime
 from unittest.mock import MagicMock, AsyncMock
+from decimal import Decimal
 
 from src.ez_lan_manager.services.AccountingService import AccountingService, InsufficientFundsError
 from src.ez_lan_manager.types.Transaction import Transaction
@@ -12,7 +13,6 @@ class AccountingServiceTests(unittest.IsolatedAsyncioTestCase):
         self.mock_database_service.add_transaction = AsyncMock()
         self.accounting_service = AccountingService(self.mock_database_service)
 
-
     def test_importing_unit_under_test_works(self) -> None:
         """
         This test asserts that the object produced in setUp is AccountingService object,
@@ -21,59 +21,59 @@ class AccountingServiceTests(unittest.IsolatedAsyncioTestCase):
         self.assertIsInstance(self.accounting_service, AccountingService)
 
     def test_making_string_from_euro_value_works_correctly(self) -> None:
-        test_value = 13466
+        test_value = Decimal("134.66")
         expected_result = "134.66 €"
-        self.assertEqual(expected_result, AccountingService.make_euro_string_from_int(test_value))
+        self.assertEqual(expected_result, AccountingService.make_euro_string_from_decimal(test_value))
 
     def test_making_euro_string_from_negative_value_works_correctly(self) -> None:
-        test_value = -99741
+        test_value = Decimal("-997.41")
         expected_result = "-997.41 €"
-        self.assertEqual(expected_result, AccountingService.make_euro_string_from_int(test_value))
+        self.assertEqual(expected_result, AccountingService.make_euro_string_from_decimal(test_value))
 
     def test_making_euro_string_from_less_than_ten_cents_works_correctly(self) -> None:
-        test_value = 4
+        test_value = Decimal("0.04")
         expected_result = "0.04 €"
-        self.assertEqual(expected_result, AccountingService.make_euro_string_from_int(test_value))
+        self.assertEqual(expected_result, AccountingService.make_euro_string_from_decimal(test_value))
 
     async def test_get_balance_correctly_adds_up_transactions(self) -> None:
         self.mock_database_service.get_all_transactions_for_user = AsyncMock(return_value=[
             Transaction(
                 user_id=0,
-                value=5,
+                value=Decimal("0.05"),
                 is_debit=True,
                 reference="",
                 transaction_date=datetime.now()
             ),
             Transaction(
                 user_id=0,
-                value=99,
+                value=Decimal("0.99"),
                 is_debit=False,
                 reference="",
                 transaction_date=datetime.now()
             ),
             Transaction(
                 user_id=0,
-                value=101,
+                value=Decimal("1.01"),
                 is_debit=False,
                 reference="",
                 transaction_date=datetime.now()
             ),
             Transaction(
                 user_id=0,
-                value=77,
+                value=Decimal("0.77"),
                 is_debit=True,
                 reference="",
                 transaction_date=datetime.now()
             ),
         ])
-        expected_result = 118
+        expected_result = Decimal("1.18")
         actual_result = await self.accounting_service.get_balance(0)
 
         self.assertEqual(expected_result, actual_result)
 
     async def test_trying_to_remove_more_than_is_on_account_balance_raises_exception(self) -> None:
-        user_balance = 100
-        balance_to_remove = 101
+        user_balance = Decimal("1.00")
+        balance_to_remove = Decimal("1.01")
         self.mock_database_service.get_all_transactions_for_user = AsyncMock(return_value=[
             Transaction(
                 user_id=0,
@@ -88,8 +88,8 @@ class AccountingServiceTests(unittest.IsolatedAsyncioTestCase):
             await self.accounting_service.remove_balance(0, balance_to_remove, "TestRef")
 
     async def test_trying_to_remove_less_than_is_on_account_balance_spawns_correct_transaction(self) -> None:
-        user_balance = 101
-        balance_to_remove = 100
+        user_balance = Decimal("1.01")
+        balance_to_remove = Decimal("1.00")
         reference = "Yey, a reference"
 
         self.mock_database_service.get_all_transactions_for_user = AsyncMock(return_value=[