--- Day 4: Ceres Search ---

"Looks like the Chief's not here. Next!" One of The Historians pulls out a device and pushes the only button on it. After a brief flash, you recognize the interior of the Ceres monitoring station!

As the search for the Chief continues, a small Elf who lives on the station tugs on your shirt; she'd like to know if you could help her with her word search (your puzzle input). She only has to find one word: XMAS.

This word search allows words to be horizontal, vertical, diagonal, written backwards, or even overlapping other words. It's a little unusual, though, as you don't merely need to find one instance of XMAS - you need to find all of them. Here are a few ways XMAS might appear, where irrelevant characters have been replaced with .:

..X...
.SAMX.
.A..A.
XMAS.S
.X....
The actual word search will be full of letters instead. For example:

MMMSXXMASM
MSAMXMSMSA
AMXSXMAAMM
MSAMASMSMX
XMASAMXAMM
XXAMMXXAMA
SMSMSASXSS
SAXAMASAAA
MAMMMXMMMM
MXMXAXMASX
In this word search, XMAS occurs a total of 18 times; here's the same word search again, but where letters not involved in any XMAS have been replaced with .:

....XXMAS.
.SAMXMS...
...S..A...
..A.A.MS.X
XMASAMX.MM
X.....XA.A
S.S.S.S.SS
.A.A.A.A.A
..M.M.M.MM
.X.X.XMASX
Take a look at the little Elf's word search. How many times does XMAS appear?

Your puzzle answer was 2434.

--- Part Two ---

The Elf looks quizzically at you. Did you misunderstand the assignment?

Looking for the instructions, you flip over the word search to find that this isn't actually an XMAS puzzle; it's an X-MAS puzzle in which you're supposed to find two MAS in the shape of an X. One way to achieve that is like this:

M.S
.A.
M.S
Irrelevant characters have again been replaced with . in the above diagram. Within the X, each MAS can be written forwards or backwards.

Here's the same example from before, but this time all of the X-MASes have been kept instead:

.M.S......
..A..MSMS.
.M.S.MAA..
..A.ASMSM.
.M.S.M....
..........
S.S.S.S.S.
.A.A.A.A..
M.M.M.M.M.
..........
In this example, an X-MAS appears 9 times.

Flip the word search from the instructions back over to the word search side and try again. How many times does an X-MAS appear?
FNAME = "data.txt"
WORD = "MMASS"


def main():
    matrix = file_to_matrix(FNAME)
    print(count_word(matrix, WORD))

def file_to_matrix(fname: str) -> list[list]:
    out = []
    fopen = open(fname, "r")
    for line in fopen:
        out.append([c for c in line if c != "\n"])
    return out

def count_word(matrix: list[list], word) -> int:
    count = 0
    len_matrix = len(matrix)
    for i in range(len_matrix):
        for j in range(len_matrix):
            count += count_word_for_pos(matrix, (i,j), word)

    return count

def count_word_for_pos(matrix: list[list], pos: tuple[int, int], word: str) -> int:
    count = 0
    if pos[0] < 1 or pos[0] > len(matrix)-2 or pos[1] < 1 or pos[1] > len(matrix)-2:
        return 0
    patterns = [[(-1,-1),(1,-1),(0,0),(-1,1),(1,1)],
                [(1,1),(-1,1),(0,0),(1,-1),(-1,-1)],
                [(-1,-1),(-1,1),(0,0),(1,-1),(1,1)],
                [(1,1),(1,-1),(0,0),(-1,1),(-1,-1)],]
    for pattern in patterns:
        s = "".join([matrix[pos[0]+p[0]][pos[1]+p[1]] for p in pattern])
        if s == word:
            return 1

    return count

if __name__ == "__main__":
    main()