--- 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?
template = [
    "S..S..S",
    ".A.A.A.",
    "..MMM.."
    "SAMXMAS",
    "..MMM.."
    ".A.A.A.",
    "S..S..S",
]

def find_xmas(lines: str) -> int:
    total = 0
    for row in range(len(lines)):
        for col in range(len(lines[row])):
            if lines[row][col] == "X":
                # Horizontal
                if col + 1 < len(lines[row]) and col + 2 < len(lines[row]) and col + 3 < len(lines[row]):
                    total += lines[row][col+1] == "M" and lines[row][col+2] == "A" and lines[row][col+3] == "S"
                
                # Horizontal reverse
                if col - 1 >= 0 and col - 2 >= 0 and col - 3 >= 0:
                    total += lines[row][col-1] == "M" and lines[row][col-2] == "A" and lines[row][col-3] == "S"

                # Vertical
                if row + 1 < len(lines) and row + 2 < len(lines) and row + 3 < len(lines):
                    total += lines[row+1][col] == "M" and lines[row+2][col] == "A" and lines[row+3][col] == "S"

                # Vertical reverse
                if row - 1 >= 0 and row - 2 >= 0 and row - 3 >= 0:
                    total += lines[row-1][col] == "M" and lines[row-2][col] == "A" and lines[row-3][col] == "S"

                # Diagonal
                if row + 1 < len(lines) and row + 2 < len(lines) and row + 3 < len(lines) and col + 1 < len(lines[row]) and col + 2 < len(lines[row]) and col + 3 < len(lines[row]):
                    total += lines[row+1][col+1] == "M" and lines[row+2][col+2] == "A" and lines[row+3][col+3] == "S"

                # Diagonal reverse
                if row - 1 >= 0 and row - 2 >= 0 and row - 3 >= 0 and col - 1 >= 0 and col - 2 >= 0 and col - 3 >= 0:
                    total += lines[row-1][col-1] == "M" and lines[row-2][col-2] == "A" and lines[row-3][col-3] == "S"

                # Diagonal reverse
                if row - 1 >= 0 and row - 2 >= 0 and row - 3 >= 0 and col + 1 < len(lines[row]) and col + 2 < len(lines[row]) and col + 3 < len(lines[row]):
                    total += lines[row-1][col+1] == "M" and lines[row-2][col+2] == "A" and lines[row-3][col+3] == "S"

                # Diagonal reverse
                if row + 1 < len(lines) and row + 2 < len(lines) and row + 3 < len(lines) and col - 1 >= 0 and col - 2 >= 0 and col - 3 >= 0:
                    total += lines[row+1][col-1] == "M" and lines[row+2][col-2] == "A" and lines[row+3][col-3] == "S"

    return total

def find_x_mas(lines: str) -> int:
    total = 0
    for row in range(len(lines)):
        for col in range(len(lines[row])):
            if lines[row][col] == "A":
                # Diagonal
                if row + 1 < len(lines) and row - 1 >= 0 and col + 1 < len(lines[row]) and col - 1 >= 0:
                    total += (((lines[row+1][col+1] == "M" and lines[row-1][col-1] == "S") or (lines[row+1][col+1] == "S" and lines[row-1][col-1] == "M"))
                    and ((lines[row+1][col-1] == "M" and lines[row-1][col+1] == "S") or (lines[row+1][col-1] == "S" and lines[row-1][col+1] == "M")))

    return total

def part1():
    input = ""
    with open("input.txt") as f:
        input = f.readlines()

    total = find_xmas(input)
    print(total)

def part2():
    input = ""
    with open("input.txt") as f:
        input = f.readlines()

    total = find_x_mas(input)
    print(total)

part2()