import string

from aocd.models import Puzzle
from aocd import submit

def eval_item_priority(rucksack: str) -> int:
    '''
        evaluates the priority of a common item
    '''

    # create a map of priority values
    priorities = dict(zip(string.ascii_letters, range(1,53)))

    # slize rucksack into compartments
    size = len(rucksack)
    a,b = rucksack[:size//2], rucksack[size//2:]

    # find the common item
    common = ''.join(
        set(a).intersection(b)
    )

    # return the priority
    return priorities[common]

def eval_badge_priority(rucksacks: list) -> int:
    '''
        evaluate the priority of duplicate items over groups of three rucksacks
    '''

    # create a map of priority values
    priorities = dict(zip(string.ascii_letters, range(1,53)))

    # find common item among three sets
    common = ''.join(
        set(rucksacks[0]) & set(rucksacks[1]) & set(rucksacks[2])
    )

    return priorities[common]

def parse_input(data: list) -> list:
    '''
        parses the input data and generates a list
    '''
    # split move set into a list of rounds
    return [ move for move in data.split('\n')]

if __name__ == "__main__":
    # get puzzle and parse data
    puzzle = Puzzle(year=2022, day=3)
    supplies = parse_input(puzzle.input_data)

    # part a: determine the priority of dupplicate items in compartments
    answer_a = sum([eval_item_priority(rucksack) for rucksack in supplies])
    print(f'sum of priorities of all common items amongst compartments: {answer_a}')
    submit(answer_a, part='a', day=3, year=2022)

    # part b: determine the priority of common items in groups of three
    # split the supply list into groups of three
    rucksacks = [ supplies[i:i+3] for i in range(0,len(supplies),3) ]
    answer_b = sum([ eval_badge_priority(rucksack) for rucksack in rucksacks ])
    print(f'sum of priorities of all common items amongst groups of three: {answer_b}')
    submit(answer_b, part='b', day=3, year=2022)