import re
import typing as t

from snsql.sql.reader.base import NameCompare

# all known identifiers quotes
KNOWN_IDENTIFIERS_QUOTE = ['"', "`", "["]


def escape_quotes(name: str) -> str:
    name_parts = split_quote(name)
    name_compare = NameCompare()
    if len(name_parts) == 1:
        return str(
            name_compare.strip_escapes(name)
            if name_compare.is_escaped(name)
            else name.lower()
        )
    return escape_quotes(name_parts[-1])


def is_quoted(name: str) -> bool:
    return any([name.startswith(quote) for quote in KNOWN_IDENTIFIERS_QUOTE])


def split_quote(
    name: str, ident_quote: t.Optional[str] = None
) -> t.Tuple[str, ...]:
    """Extract qualified column or table names.
    It supports names containing dots or special characters.
    If ident_quote is provided it will quote all the name parts accordinly
    otherwise it will leave names as they are.
    If an empty string is provided it will unquote

    Args:
        name (str):
        ident_quote (str): the quote identifier

    Returns:
        Tuple[str, ...]:
    """

    regex = re.compile(r"""((?:[^."\[\]]|"[^"]*"|\[[^\[]*\])+)""")
    parts = [
        sub_name for sub_name in regex.split(name) if sub_name not in [".", ""]
    ]

    if ident_quote is not None:
        parts = [
            f"{ident_quote}{part[1:-1]}{ident_quote}"
            if is_quoted(part)
            else f"{ident_quote}{part}{ident_quote}"
            for part in parts
        ]
    return tuple(parts)


def expand_fully_qualified_name(
    fully_qualified_name: t.Tuple[str, ...],
) -> t.List[t.Tuple[str, ...]]:
    """Expands fully qualified table names in all possible suffixes.
    e.g: (a, b, c, d,) ->  [(a, b, c, d,), (b, c, d,), (c, d,), (d,)]
    """
    all_qualified_names = []
    for idx in range(len(fully_qualified_name)):
        all_qualified_names.append(fully_qualified_name[idx:])
    return all_qualified_names