add methods check_statement, __load_transactions and withdraw

Author: EmanuelQuintino

project/cash_machine.py

@@ -0,0 +1,101 @@
+class Bank_account:
+  def __init__(self, balance = 0):
+    self.__balance = balance
+    self.__file = "project/files/transactions.txt"
+    self.__transactions = []
+    self.__load_transactions()
+
+  def check_statement(self):
+    print("===== Extrato =====")
+
+    for transaction in self.__transactions:
+      print(f"{transaction[0]}: {transaction[1]}")
+
+    print("===================")
+    print(f"Saldo (=): {self.__balance}")
+    print("===================")
+
+  def __load_transactions(self):
+    try:
+      with open(self.__file, "r") as file:
+        for line in file:
+          transaction, amount = line.strip().split(", ")
+          amount = float(amount)
+
+          self.__transactions.append((transaction, amount))
+
+          if transaction == "deposito (+)":
+            self.__balance += amount
+          elif transaction == "saque (-)":
+            self.__balance -= amount
+    except:
+      print("Algo deu errado em abrir o arquivo!")
+      pass
+
+  def deposit(self, amount):
+    self.__balance += amount
+
+    try:
+      with open(self.__file, "a") as file:
+        file.write(f"deposito (+), {amount}\n")
+        self.__transactions.append(("deposito (+)", amount))
+    except:
+      print("Algo deu errado em abrir o arquivo!")
+      pass
+
+    print(f"Depósito de R${amount} realizado!")
+
+  def withdraw(self, amount):
+    if amount == 0:
+      return print("Saque deve ser maior que zero!")
+    
+    if amount <= self.__balance:
+      self.__balance -= amount
+
+      try:
+        with open(self.__file, "a") as file:
+          file.write(f"saque (-), {amount}\n")
+          self.__transactions.append(("saque (-)", amount))
+      except:
+        print("Algo deu errado em abrir o arquivo!")
+        pass
+
+      print(f"Saque de R${amount} realizado!")
+    else:
+      print("Saldo insuficiente!")
+
+account = Bank_account()
+waiting_menu = False # flag
+while True:
+  if waiting_menu == True:
+    input("\nPressine Enter para seguir...")
+
+  # print("\033[H\033[J") # terminal clear
+  # print("\033c", end="") # terminal clear
+  waiting_menu = True
+  
+  print('''
+=== Automated Teller Machine ===
+    [1] Ver extrato
+    [2] Fazer o depósito
+    [3] Fazer saque
+    [4] Sair
+================================
+''')
+
+  option = input("\bEscolha uma opção: ")
+  print("")
+
+  if option == "1":
+    account.check_statement()
+  elif option == "2":
+    amount = float(input("Digite o valor para depositar: "))
+    account.deposit(amount)
+  elif option == "3":
+    amount = float(input("Digite o valor para saque: "))
+    account.withdraw(amount)
+  elif option == "4":
+    print("Programa encerrado!\n")
+    break
+  else:
+    print("Opção inválida!")

project/files/transactions.txt

@@ -0,0 +1,4 @@
+deposito (+), 200.0
+deposito (+), 300.0
+saque (-), 400.0
+saque (-), 100.0