from collections import deque
from typing_extensions import Self


class BasicRegister:
    """
    The BasicRegister represents a hardware register capable of manipulating multiple bits at a time.

    :param deque[bool] memory: The bits stored inside the register.
    """

    def __init__(self, memory: list[bool]):
        self.memory: deque[bool] = deque(memory)

    def __repr__(self) -> str:
        return f"Memory: {[int(value) for value in  self.memory]}"

    def __str__(self) -> str:
        return f"Memory: {[int(value) for value in  self.memory]}"

    def __len__(self) -> int:
        return len(self.memory)

    def adjusted_by_size(self, resulting_size: int) -> Self:
        """
        Adjusts a register to a given size.

        :param int resulting_size: The size of the resulting register.

        :return: A register of a specified size.
        :rtype: BasicRegister
        """
        current_memory_size: int = len(self.memory)
        return BasicRegister(
            [False] * max(resulting_size - current_memory_size, 0) + list(self.memory)[-resulting_size:]
        )

    def reverse(self):
        """
        Performs a logical negation on the register.
        """
        self.memory = deque([not value for value in self.memory])

    def left_shift(self, shift_in_value: bool = False, bits_shifted: int = 1) -> deque[bool]:
        """
        Shifts the register to the left by a specified number of steps

        :param bool shift_in_value: The value that shifts inside the freed space.
        :param int bits_shifted: The number of bits by which the register is shifted.

        :return: The bits shifted outside the register.
        :rtype: deque[bool]
        """
        self.memory.extend([shift_in_value] * bits_shifted)
        shifted_bits: deque[bool] = deque([self.memory.popleft() for _i in range(bits_shifted)])
        return shifted_bits

    def right_shift(self, shift_in_value: bool = False, bits_shifted: int = 1) -> deque[bool]:
        """
        Shifts the register to the right by a specified number of steps

        :param bool shift_in_value: The value that shifts inside the freed space.
        :param int bits_shifted: The number of bits by which the register is shifted.

        :return: The bits shifted outside the register.
        :rtype: deque[bool]
        """
        self.memory.extendleft([shift_in_value] * bits_shifted)
        shifted_bits: deque[bool] = deque([self.memory.pop() for _i in range(bits_shifted)])
        return shifted_bits


def get_memory(variable_name: str) -> list[bool]:
    """
    Reads user input to be used as a memory array.

    :param str variable_name: The name to be displayed in the input line.

    :return: A list of boolean values read from user.
    :rtype: list[bool]
    """
    while True:
        input_chars: list[str] = list(input(f"Enter {variable_name}: "))

        if all(character in ["0", "1"] for character in input_chars):
            return [True if character == "1" else False for character in input_chars]
        else:
            print(f"[ERROR] The {variable_name} may contain only 1-s and 0-s!")


def binary_sum_with_carry(first_term: BasicRegister, second_term: BasicRegister) -> tuple[BasicRegister, int]:
    """
    Sums two registers' values and keeps the carry-out.

    :param BasicRegister first_term: First register.
    :param BasicRegister second_term: Second register.

    :return: Register containing the sum and the carry-out bit.
    :rtype: tuple[BasicRegister, int]
    """
    result_term = BasicRegister([False] * len(first_term))

    carry = False
    for i in range(len(first_term) - 1, 0, -1):
        current_bit_sum = first_term.memory[i] + second_term.memory[i] + carry
        carry = bool(current_bit_sum & 2)
        result_term.memory[i] = bool(current_bit_sum & 1)

    final_bit_sum = first_term.memory[0] + second_term.memory[0] + carry
    final_carry = bool(final_bit_sum & 2)
    result_term.memory[0] = bool(final_bit_sum & 1)

    return result_term, final_carry


def binary_sum(first_term: BasicRegister, second_term: BasicRegister) -> BasicRegister:
    """
    Sums two terms containing binary numbers.

    :param BasicRegister first_term: First register to add.
    :param BasicRegister second_term: Second register to add.

    :return: Register containing the sum.
    :rtype: BasicRegister
    """
    return binary_sum_with_carry(first_term, second_term)[0]


def binary_subtraction(minuend: BasicRegister, subtrahend: BasicRegister) -> BasicRegister:
    """
    Subtracts the second term from the first in binary using ones' complement.

    :param BasicRegister minuend: Register to subtract from.
    :param BasicRegister subtrahend: Register to subtract by.

    :return: Register containing the difference.
    :rtype: BasicRegister
    """
    subtrahend.reverse()

    difference: BasicRegister
    final_carry: bool
    difference, final_carry = binary_sum_with_carry(minuend, subtrahend)

    if final_carry:
        return binary_sum(difference, BasicRegister([False] * (len(difference) - 1) + [True]))
    else:
        difference.reverse()
        return difference


# def align_registers(first_register: BasicRegister, second_register: BasicRegister) \
#         -> tuple[BasicRegister, BasicRegister]:
#     """
#     Aligns two registers by the length of the bigger one.
#
#     :param BasicRegister first_register:
#     :param BasicRegister second_register:
#
#     :return:
#     :rtype: tuple[BasicRegister, BasicRegister]
#     """
#     first_size = len(first_register)
#     second_size = len(second_register)
#
#     required_size = max(first_size, second_size)
#
#     if first_size != second_size:
#         return first_register.adjusted_by_size(required_size), second_register.adjusted_by_size(required_size)
#     else:
#         return first_register, second_register


def align_registers(*registers: BasicRegister) -> tuple[BasicRegister, ...]:
    """
    Aligns registers by the length of the bigger one.

    :param BasicRegister registers: Registers to align.

    :return: Aligned registers.
    :rtype: tuple[BasicRegister, ...]
    """
    required_size: int = max(map(len, registers))
    return tuple(reg.adjusted_by_size(required_size) for reg in registers)