"""File_utils - Read a csv file and return a grid of [letter, color].

Author: YOUR_NAME
Version: THE DATE
"""

import os
import sys

# Type aliases
Cell = list[str]
Grid = list[Cell]


def parse_cell(cell_str: str) -> Cell:
    """Parse a single CSV file item and return [letter, color].

    Take a single cell string (ex. "[A]"). Look for the surrounding characters
    bracket/paren/underscore; otherwise we classify as INVALID and make the letter *.
    Use the color coding rules from the specification. Treat any letters not surrounded
    by the correct characters as letter "*" and "INVALID" color i.e. space surrounded
    letters and plain letters, with no surrounding characters.

    Args:
        cell_str: A single cell string

    Returns:
        A two-element list of [letter, color].
    """
    pass
    return ["A", "GREEN"]


def read_file(filename: str) -> Grid:
    """Read the file and return a flat list of rows.

    Skip any empty lines. You may need to handle the newline character
    at the end of each line, then read individual items by splitting on commas.
    See sample starter.txt and solution.txt for examples of valid files to read.

    Args:
        filename: Filename of the CSV file to read.

    Returns:
        A flat list of [letter, color] pairs, in reading order
        (left-to-right, top-to-bottom, from the input file).
    """
    pass
    return []


def write_log(swap: tuple[str, str]) -> bool:
    """Append a swap tuple to `log.txt` in this module's directory.

    Each letter must be a single character in the range 'a' through 'y'. The pair
    is written as a single line in the form "a,w" followed by newline character.
    Sample partial log.txt file contents:
    d,b
    m,c
    o,m
    j,h
    j,r

    Args:
        swap: tuple made up of two letters, e.g., ('a', 'y')

    Returns:
        True if the write succeeded, False for invalid input or IO errors.
    """
    pass
    return True


def print_log() -> None:
    """Read and print the contents of log.txt showing all moves made.

    print a header: MOVE LOG (from log.txt)
    Then print each line for log.txt in this format:
    Move 1: d,b
    Move 2: m,c
    If there are no moves, print: No moves recorded with newlines before and after.
    If log.txt does not exist, print: No log.txt file found with newlines before and after.
    """
    pass


def valid_border(raw: str) -> bool:
    """Check if the raw string has valid border markers i.e. [ ],( ), or_ _.

    Args:
        raw: The raw string including borders.

    Returns:
        True if the string has valid borders, False otherwise.
    """
    pass
    return False


def check_grid(grid: Grid) -> str:
    """Check if a 5x5 grid is correct for the Waffle game.

    Return valid if the grid is correct and an error code describing the
    problem area otherwise(see Returns below for details).
    valid colors are "GREEN", "YELLOW", and "RED"

    Args:
        grid: A flat list of 25 cells, each cell being either
              [letter, color] or [letter, color, raw_string].

    Returns:
        "border" if any cell is not bordered by [], (), or __;
        "color" if any color is invalid;
        "letter" if any letter is not A-Z or _;
        "size" if the grid does not have exactly 25 cells;
        "valid" if all cells are correct.
    """
    pass
    return "valid"


if __name__ == "__main__":
    # Additional test code can go here.
    pass