'''AoC 2025 Day 1'''
import math

def turn_dial(curr_pos: int, instruction: str) -> int:
    '''Turn dial from current position to the new one'''
    direction, amount = process_instruction(instruction)

    new_pos = (curr_pos + (direction * amount)) % 100

    return new_pos


def check_cross_zero(curr_pos: int, instruction: str) -> int:
    '''Check for if the instruction crosses 0 and lands on it'''
    direction, amount = process_instruction(instruction)

    total_zeros = 0

    if direction == 1 and curr_pos + amount >= 100:
        total_zeros += math.floor((curr_pos + amount) / 100)
    if direction == -1 and curr_pos - amount <= 0:
        total_zeros += math.floor(abs((curr_pos - amount) / 100))
        if curr_pos != 0:
            total_zeros += 1

    return total_zeros


def process_instruction(instruction: str) -> (int, int):
    '''Returns the direction and amount of the turn'''
    direction = -1 if instruction[0] == 'L' else 1
    amount = int(instruction[1:])

    return direction, amount


def main():
    '''Entrypoint'''
    curr_pos = 50

    num_zero = 0
    crossing_zero = 0

    with open('input.txt', encoding='utf-8') as fh:
        for line in fh:
            crossing_zero += check_cross_zero(curr_pos, line.strip())

            curr_pos = turn_dial(curr_pos, line.strip())

            if curr_pos == 0:
                num_zero += 1

    print(f'Part1: {num_zero}')

    print(f'Part2: {crossing_zero}')


if __name__ == "__main__":
    main()