from config import ADMIN_PASSWORD


class CLI:
    def __init__(self, tracker) -> None:
        self.tracker = tracker
        self.current_user = None

    def run(self):
        while True:
            self._clear_screen()
            self._show_main_menu()

    def _clear_screen(self):
        import subprocess
        import os

        subprocess.run("cls" if os.name == "nt" else "clear")

    def _show_main_menu(self):
        print("=" * 50)
        print("DEBT TRACKER")
        print("=" * 50)

        if self.current_user:
            user = self.tracker.get_user_by_id(self.current_user)
            debt = self.tracker.get_user_debt(self.current_user)
            print(f"\nLogged in as: {user.name}")
            print(f"Current Debt: ${debt:.2f}\n")

        print("1. Select user")
        print("2. View all debts")
        print("3. Admin panel")
        print("4. Exit")
        print()

        choice = input("Choose Option: ").strip()

        if choice == "1":
            self._select_user()
        elif choice == "2":
            self._view_all_debts()
        elif choice == "3":
            self._admin_panel()
        elif choice == "4":
            print("\nGoodbye!")
            exit()
        else:
            self._invalid_choice()

    def _select_user(self):
        self._clear_screen()
        print("=" * 50)
        print("SELECT USER")
        print("=" * 50)
        print()

        users = self.tracker.get_all_users()
        user_list = list(users.items())

        for i, (user_id, user) in enumerate(user_list, 1):
            debt = self.tracker.get_user_debt(user_id)
            print(f"{i}. {user.name} (Debt: ${debt:.2f})")

        print(f"{len(user_list) + 1}. Back to main menu")
        print()

        try:
            choice = int(input("Choose user: ").strip())

            if choice == len(user_list) + 1:
                return

            if 1 <= choice <= len(user_list):
                self.current_user = user_list[choice - 1][0]
                self._user_menu()
            else:
                self._invalid_choice()
        except ValueError:
            self._invalid_choice()

    def _user_menu(self):
        while True:
            self._clear_screen()
            user = self.tracker.get_user_by_id(self.current_user)
            debt = self.tracker.get_user_debt(self.current_user)

            print("=" * 50)
            print(f"USER MENU - {user.name}")
            print("=" * 50)
            print(f"Current debt: ${debt:.2f}\n")

            print("1. Add purchase")
            print("2. View my debt")
            print("3. Logout")
            print()

            choice = input("Choose option: ").strip()

            if choice == "1":
                self._add_purchase()
            elif choice == "2":
                self._view_user_debt()
            elif choice == "3":
                self.current_user = None
                break
            else:
                self._invalid_choice()

    def _add_purchase(self):
        self._clear_screen()
        print("=" * 50)
        print("ADD PURCHASE")
        print("=" * 50)
        print()

        menu_items = self.tracker.get_items()
        item_list = list(menu_items.items())

        for i, (_item_id, item) in enumerate(item_list, 1):
            print(f"{i}. {item.name} - ${item.price:.2f}")

        print(f"{len(item_list) + 1}. Cancel")
        print()

        try:
            choice = int(input("Choose item: ").strip())

            if choice == len(item_list) + 1:
                return

            if 1 <= choice <= len(item_list):
                selected_item_id = item_list[choice - 1][0]
                self._confirm_purchase(selected_item_id)
            else:
                self._invalid_choice()
        except ValueError:
            self._invalid_choice()

    def _confirm_purchase(self, item_id):
        self._clear_screen()

        user = self.tracker.get_user_by_id(self.current_user)
        item = self.tracker.get_items()[item_id]

        print("=" * 50)
        print("CONFIRM PURCHASE")
        print("=" * 50)
        print()
        print(f"User: {user.name}")
        print(f"Item: {item.name}")
        print(f"Price: ${item.price:.2f}")
        print()

        confirm = input("Add to debt? (y/n): ").strip().lower()

        if confirm == "y":
            result = self.tracker.add_purchase(self.current_user, item_id)

            self._clear_screen()
            print("=" * 50)
            print("PURCHASE ADDED")
            print("=" * 50)
            print()
            print(f"✓ {result['message']}")
            print(f"New debt: ${result['new_debt']:.2f}")
            print()

            input("Press Enter to continue...")
        else:
            print("Purchase cancelled.")
            input("Press Enter to continue...")

    def _view_user_debt(self):
        self._clear_screen()

        user = self.tracker.get_user_by_id(self.current_user)
        debt = self.tracker.get_user_debt(self.current_user)

        print("=" * 50)
        print(f"DEBT - {user.name}")
        print("=" * 50)
        print()
        print(f"Amount owed: ${debt:.2f}")
        print()

        input("Press Enter to continue...")

    def _view_all_debts(self):
        self._clear_screen()
        print("=" * 50)
        print("ALL DEBTS")
        print("=" * 50)
        print()

        all_debts = self.tracker.get_all_debts()

        if not all_debts:
            print("No users with debt.")
        else:
            total = 0
            for _user_id, debt_info in all_debts.items():
                amount = debt_info["debt"]
                print(f"{debt_info['name']:.<30} ${amount:>7.2f}")
                total += amount

            print("-" * 50)
            print(f"{'TOTAL':.<30} ${total:>7.2f}")

        print()
        input("Press Enter to continue...")

    def _admin_panel(self):
        self._clear_screen()
        print("=" * 50)
        print("ADMIN PANEL")
        print("=" * 50)
        print()

        password = input("Enter admin password: ").strip()

        if password != ADMIN_PASSWORD:
            print("Invalid password!")
            input("Press Enter to continue...")
            return

        while True:
            self._clear_screen()
            print("=" * 50)
            print("ADMIN PANEL")
            print("=" * 50)
            print()

            print("1. View all debts")
            print("2. Adjust user debt")
            print("3. Clear user debt")
            print("4. View transaction history")
            print("5. Manage users")
            print("6. Manage items")
            print("7. Logout")
            print()

            choice = input("Choose option: ").strip()

            if choice == "1":
                self._view_all_debts()
            elif choice == "2":
                self._adjust_debt()
            elif choice == "3":
                self._clear_user_debt()
            elif choice == "4":
                self._view_transaction_history()
            elif choice == "5":
                self._manage_users()
            elif choice == "6":
                self._manage_items()
            elif choice == "7":
                break
            else:
                self._invalid_choice()

    def _adjust_debt(self):
        self._clear_screen()
        print("=" * 50)
        print("ADJUST DEBT")
        print("=" * 50)
        print()

        users = self.tracker.get_all_users()
        user_list = list(users.items())

        for i, (user_id, user) in enumerate(user_list, 1):
            debt = self.tracker.get_user_debt(user_id)
            print(f"{i}. {user.name} - ${debt:.2f}")

        print()

        try:
            choice = int(input("Choose user: ").strip())

            if 1 <= choice <= len(user_list):
                user_id = user_list[choice - 1][0]

                amount_str = input("Amount paid: $").strip()
                amount = float(amount_str)

                result = self.tracker.adjust_debt(user_id, amount, ADMIN_PASSWORD)

                self._clear_screen()
                print("=" * 50)
                print("DEBT ADJUSTED")
                print("=" * 50)
                print()
                print(f"{result['message']}")
                print(f"New debt: ${result['new_debt']:.2f}")
                print()

                input("Press Enter to continue...")
            else:
                self._invalid_choice()
        except ValueError:
            print("Invalid input!")
            input("Press Enter to continue...")

    def _clear_user_debt(self):
        self._clear_screen()
        print("=" * 50)
        print("CLEAR USER DEBT")
        print("=" * 50)
        print()

        users = self.tracker.get_all_users()
        user_list = list(users.items())

        for i, (user_id, user) in enumerate(user_list, 1):
            debt = self.tracker.get_user_debt(user_id)
            print(f"{i}. {user.name} - ${debt:.2f}")

        print()

        try:
            choice = int(input("Choose user: ").strip())

            if 1 <= choice <= len(user_list):
                user_id = user_list[choice - 1][0]
                debt_amount = self.tracker.get_user_debt(user_id)

                confirm = input(f"Clear ${debt_amount:.2f}? (y/n): ").strip().lower()

                if confirm == "y":
                    _result = self.tracker.adjust_debt(
                        user_id, debt_amount, ADMIN_PASSWORD
                    )

                    self._clear_screen()
                    print("=" * 50)
                    print("DEBT CLEARED")
                    print("=" * 50)
                    print()
                    print(
                        f"Debt cleared for {self.tracker.get_user_by_id(user_id).name}"
                    )
                    print()

                    input("Press Enter to continue...")
            else:
                self._invalid_choice()
        except ValueError:
            print("Invalid input!")
            input("Press Enter to continue...")

    def _view_transaction_history(self):
        self._clear_screen()
        print("=" * 50)
        print("TRANSACTION HISTORY")
        print("=" * 50)
        print()

        transactions = self.tracker.transactions

        if not transactions:
            print("No transactions yet.")
        else:
            for t in sorted(transactions, key=lambda x: x.timestamp, reverse=True):
                user = self.tracker.get_user_by_id(t.user_id)
                item = self.tracker.get_items().get(t.item_id)
                item_name = item.name if item else ("Adjustment" if t.item_id == "adjustment" else "Deleted Item")
                print(
                    f"{t.timestamp[:10]} | {user.name:.<20} {item_name:.<15} ${t.amount:.2f}"
                )

        print()
        input("Press Enter to continue...")

    def _invalid_choice(self):
        print("Invalid choice. Please try again.")
        input("Press Enter to continue...")

    def _manage_users(self):
        while True:
            self._clear_screen()
            print("=" * 50)
            print("MANAGE USERS")
            print("=" * 50)
            print()
            print("1. Add user")
            print("2. Edit user")
            print("3. Remove user")
            print("4. Back to admin panel")
            print()
            choice = input("Choose option: ").strip()
            if choice == "1":
                self._cli_add_user()
            elif choice == "2":
                self._cli_edit_user()
            elif choice == "3":
                self._cli_remove_user()
            elif choice == "4":
                break
            else:
                self._invalid_choice()

    def _cli_add_user(self):
        self._clear_screen()
        print("=" * 50)
        print("ADD USER")
        print("=" * 50)
        print()
        name = input("Enter new user's name: ").strip()
        if not name:
            print("Name cannot be empty!")
            input("Press Enter to continue...")
            return
        import uuid
        user_id = f"user_{uuid.uuid4().hex[:8]}"
        res = self.tracker.add_user(user_id, name)
        print(res["message"])
        input("Press Enter to continue...")

    def _cli_edit_user(self):
        self._clear_screen()
        print("=" * 50)
        print("EDIT USER")
        print("=" * 50)
        print()
        users = self.tracker.get_all_users()
        user_list = list(users.items())
        for i, (user_id, user) in enumerate(user_list, 1):
            print(f"{i}. {user.name} (PIN: {user.pin})")
        print(f"{len(user_list) + 1}. Cancel")
        print()
        try:
            choice = int(input("Choose user to edit: ").strip())
            if choice == len(user_list) + 1:
                return
            if 1 <= choice <= len(user_list):
                user_id = user_list[choice - 1][0]
                user = users[user_id]
                new_name = input(f"Enter new name (leave empty to keep '{user.name}'): ").strip()
                new_pin = input(f"Enter new PIN (leave empty to keep '{user.pin}'): ").strip()
                name = new_name if new_name else user.name
                pin = new_pin if new_pin else user.pin
                if len(pin) < 4:
                    print("PIN must be at least 4 digits!")
                    input("Press Enter to continue...")
                    return
                res = self.tracker.edit_user(user_id, name, pin)
                print(res["message"])
                input("Press Enter to continue...")
            else:
                self._invalid_choice()
        except ValueError:
            self._invalid_choice()

    def _cli_remove_user(self):
        self._clear_screen()
        print("=" * 50)
        print("REMOVE USER")
        print("=" * 50)
        print()
        users = self.tracker.get_all_users()
        user_list = list(users.items())
        for i, (user_id, user) in enumerate(user_list, 1):
            print(f"{i}. {user.name}")
        print(f"{len(user_list) + 1}. Cancel")
        print()
        try:
            choice = int(input("Choose user to remove: ").strip())
            if choice == len(user_list) + 1:
                return
            if 1 <= choice <= len(user_list):
                user_id = user_list[choice - 1][0]
                confirm = input(f"Are you sure you want to delete {users[user_id].name}? (y/n): ").strip().lower()
                if confirm == "y":
                    res = self.tracker.remove_user(user_id)
                    print(res["message"])
                    input("Press Enter to continue...")
            else:
                self._invalid_choice()
        except ValueError:
            self._invalid_choice()

    def _manage_items(self):
        while True:
            self._clear_screen()
            print("=" * 50)
            print("MANAGE ITEMS")
            print("=" * 50)
            print()
            print("1. Add item")
            print("2. Edit item")
            print("3. Remove item")
            print("4. Back to admin panel")
            print()
            choice = input("Choose option: ").strip()
            if choice == "1":
                self._cli_add_item()
            elif choice == "2":
                self._cli_edit_item()
            elif choice == "3":
                self._cli_remove_item()
            elif choice == "4":
                break
            else:
                self._invalid_choice()

    def _cli_add_item(self):
        self._clear_screen()
        print("=" * 50)
        print("ADD ITEM")
        print("=" * 50)
        print()
        name = input("Enter item name: ").strip()
        if not name:
            print("Name cannot be empty!")
            input("Press Enter to continue...")
            return
        price_str = input("Enter price ($): ").strip()
        try:
            price = float(price_str)
            if price < 0:
                raise ValueError
        except ValueError:
            print("Invalid price!")
            input("Press Enter to continue...")
            return
        import uuid
        item_id = f"item_{uuid.uuid4().hex[:8]}"
        res = self.tracker.add_item(item_id, name, price)
        print(res["message"])
        input("Press Enter to continue...")

    def _cli_edit_item(self):
        self._clear_screen()
        print("=" * 50)
        print("EDIT ITEM")
        print("=" * 50)
        print()
        items = self.tracker.get_items()
        item_list = list(items.items())
        for i, (item_id, item) in enumerate(item_list, 1):
            print(f"{i}. {item.name} (${item.price:.2f})")
        print(f"{len(item_list) + 1}. Cancel")
        print()
        try:
            choice = int(input("Choose item to edit: ").strip())
            if choice == len(item_list) + 1:
                return
            if 1 <= choice <= len(item_list):
                item_id = item_list[choice - 1][0]
                item = items[item_id]
                new_name = input(f"Enter new name (leave empty to keep '{item.name}'): ").strip()
                new_price_str = input(f"Enter new price (leave empty to keep '${item.price:.2f}'): ").strip()
                name = new_name if new_name else item.name
                price = item.price
                if new_price_str:
                    try:
                        price = float(new_price_str)
                        if price < 0:
                            raise ValueError
                    except ValueError:
                        print("Invalid price!")
                        input("Press Enter to continue...")
                        return
                res = self.tracker.edit_item(item_id, name, price)
                print(res["message"])
                input("Press Enter to continue...")
            else:
                self._invalid_choice()
        except ValueError:
            self._invalid_choice()

    def _cli_remove_item(self):
        self._clear_screen()
        print("=" * 50)
        print("REMOVE ITEM")
        print("=" * 50)
        print()
        items = self.tracker.get_items()
        item_list = list(items.items())
        for i, (item_id, item) in enumerate(item_list, 1):
            print(f"{i}. {item.name} (${item.price:.2f})")
        print(f"{len(item_list) + 1}. Cancel")
        print()
        try:
            choice = int(input("Choose item to remove: ").strip())
            if choice == len(item_list) + 1:
                return
            if 1 <= choice <= len(item_list):
                item_id = item_list[choice - 1][0]
                confirm = input(f"Are you sure you want to delete {items[item_id].name}? (y/n): ").strip().lower()
                if confirm == "y":
                    res = self.tracker.remove_item(item_id)
                    print(res["message"])
                    input("Press Enter to continue...")
            else:
                self._invalid_choice()
        except ValueError:
            self._invalid_choice()