Initial commit

app/transaction.py

@@ -0,0 +1,34 @@
+class Transaction:
+    def __init__(self, database):
+        self.database = database
+
+    def deposit(self, account_id, amount):
+        if amount <= 0:
+            raise ValueError("Amount must be positive.")
+        account = self.database.get_account(account_id)
+        if not account:
+            raise ValueError("Account does not exist.")
+        new_balance = account[3] + amount
+        self.database.update_account_balance(account_id, new_balance)
+        self.database.add_transaction(None, account_id, amount, "deposit")
+
+    def withdraw(self, account_id, amount):
+        if amount <= 0:
+            raise ValueError("Amount must be positive.")
+        account = self.database.get_account(account_id)
+        if account[3] < amount:
+            raise ValueError("Insufficient funds.")
+        new_balance = account[3] - amount
+        self.database.update_account_balance(account_id, new_balance)
+        self.database.add_transaction(account_id, None, amount, "withdrawal")
+
+    def transfer(self, from_account_id, to_account_id, amount):
+        if amount <= 0:
+            raise ValueError("Amount must be positive.")
+        from_account = self.database.get_account(from_account_id)
+        to_account = self.database.get_account(to_account_id)
+        if from_account[3] < amount:
+            raise ValueError("Insufficient funds in the source account.")
+        self.database.update_account_balance(from_account_id, from_account[3] - amount)
+        self.database.update_account_balance(to_account_id, to_account[3] + amount)
+        self.database.add_transaction(from_account_id, to_account_id, amount, "transfer")