week12.py

import sys

class Record:
    """Represents a financial record with a category, description, and amount."""
    def __init__(self, category, description, amount):
        self._category = category
        self._description = description
        self._amount = float(amount)
    
    @property
    def category(self):
        return self._category
    
    @property
    def description(self):
        return self._description
    
    @property
    def amount(self):
        return self._amount

class Records:
    """Manages a collection of Record instances and overall financial balance."""
    def __init__(self):
        try:
            with open('records.txt', 'r') as file:
                self._initial_money = float(file.readline().strip())
                self._records = [Record(*line.strip().split(', ')) for line in file.readlines()]
        except FileNotFoundError:
            self._initial_money = float(input("How much money do you have? "))
            self._records = []

    def add(self, entry, categories):
        cat, desc, amt = entry.split(" ")
        if categories.is_category_valid(cat):
            self._records.append(Record(cat, desc, float(amt)))
            self._initial_money += float(amt)
        else:
            print(f"The specified category '{cat}' is not in the category list.")

    def view(self):
        print("Here's your expense and income records:")
        print("Category        Description          Amount")
        print("=============== ==================== ======")
        for record in self._records:
            print(f"{record.category:15} {record.description:20} {record.amount:5.2f}")
        print("===========================================")
        print(f"Now you have {self._initial_money:.2f} dollars.")

    def delete(self, index):
        try:
            index = int(index) - 1
            if 0 <= index < len(self._records):
                self._initial_money -= self._records[index].amount
                del self._records[index]
            else:
                print("Invalid record number.")
        except ValueError:
            print("Please enter a valid number.")

    def find(self, subcategories):
        print("Category        Description          Amount")
        print("=============== ==================== ======")
        total = 0
        for record in self._records:
            if record.category in subcategories:
                print(f"{record.category:15} {record.description:20} {record.amount:5.2f}")
                total += record.amount
        print("===========================================")
        print(f"The total amount above is {total:.2f}.")

    def save(self):
        with open('records.txt', 'w') as file:
            file.write(f"{self._initial_money}\n")
            for record in self._records:
                file.write(f"{record.category}, {record.description}, {record.amount}\n")

class Categories:
    """Manages categories and validates them against a predefined list."""
    def __init__(self):
        self._categories = [
            'expense', [
                'food', [
                    'meal', 
                    'snack', 
                    'drink'
                ],
                'transportation', [
                    'bus', 
                    'railway'
                ]
            ],
            'income', [
                'salary', 
                'bonus'
            ]
        ]

    def view(self, categories=None, level=0):
        if categories is None:
            categories = self._categories
        if isinstance(categories, list):
            for category in categories:
                self.view(category, level + 1)
        else:
            print('  ' * level + '- ' + categories)

    def is_category_valid(self, category, categories=None):
        if categories is None:
            categories = self._categories
        if isinstance(categories, list):
            for subcat in categories:
                if self.is_category_valid(category, subcat):
                    return True
        return category == categories

    def find_subcategories(self, category, categories=None):
        if categories is None:
            categories = self._categories
        if isinstance(categories, list):
            for i in range(0, len(categories), 2):
                print(categories[i], category == categories[i])
                if categories[i] == category:
                    return [category] + self._flatten(categories[i + 1])
                result = self.find_subcategories(category, categories[i + 1])
                if result:
                    return result
        return [category] if category == categories else []

    def _flatten(self, categories):
        if isinstance(categories, list):
            flat_list = []
            for element in categories:
                flat_list.extend(self._flatten(element))
            return flat_list
        else:
            return [categories]


categories = Categories()
records = Records()

while True:
    command = input('\nWhat do you want to do (add / view / delete / view categories / find / exit)? ')
    if command == 'add':
        entry = input('Add some expense or income records with category, description, and amount (separate by spaces):\n')
        records.add(entry, categories)
    elif command == 'view':
        records.view()
    elif command == 'delete':
        delete_record = input("Which record number do you want to delete? ")
        records.delete(delete_record)
    elif command == 'view categories':
        categories.view()
    elif command == 'find':
        category = input('Which category do you want to find? ')
        target_categories = categories.find_subcategories(category)
        records.find(target_categories)
    elif command == 'exit':
        records.save()
        print("Changes saved. Exiting.")
        break
    else:
        sys.stderr.write('Invalid command. Try again.\n')