# Copyright 2022 (c) Anna Schumaker
"""Helper functions for formatting strings."""
import re

IGNORE_WORDS = set(["a", "an", "the", ""])


def search(input: str) -> str | None:
    """Translate the input string into a sqlite3 GLOB statement."""
    input = input.strip().casefold()
    if len(input) == 0:
        return None

    if input[0] == "^":
        input = input[1:] if len(input) > 1 else "*"
    elif input[0] != "*":
        input = "*" + input

    if input[-1] == "$":
        input = input[:-1]
    elif input[-1] != "*":
        input += "*"

    return input


def sort_key(input: str) -> tuple:
    """Translate the input string into a sort key."""
    if len(input) == 0:
        return ()
    input = re.sub(r"[\"\'’“”]", "", input.casefold())
    res = re.split(r"[ /_-]", input)
    if len(res) > 1 and res[0] in IGNORE_WORDS:
        res = res[1:]
    return tuple(res)