"""ANSI color helpers and shared logger."""
from __future__ import annotations

import logging
import re as _re
import sys

_USE_COLOR = sys.stderr.isatty()


def _c(code: str, text: str) -> str:
    return f"\033[{code}m{text}\033[0m" if _USE_COLOR else text

def _dim(t: str)         -> str: return _c("2",    t)
def _bold(t: str)        -> str: return _c("1",    t)
def _red(t: str)         -> str: return _c("31",   t)
def _green(t: str)       -> str: return _c("32",   t)
def _yellow(t: str)      -> str: return _c("33",   t)
def _cyan(t: str)        -> str: return _c("36",   t)
def _bold_red(t: str)    -> str: return _c("1;31", t)
def _bold_green(t: str)  -> str: return _c("1;32", t)
def _bold_yellow(t: str) -> str: return _c("1;33", t)
def _bold_cyan(t: str)   -> str: return _c("1;36", t)


def _vis_len(s: str) -> int:
    """Visible character width of a string, ignoring ANSI escape sequences."""
    return len(_re.sub(r'\033\[[0-9;]*m', '', s))


class _ColorFormatter(logging.Formatter):
    _STYLES = {
        logging.DEBUG:    "2",
        logging.INFO:     "36",
        logging.WARNING:  "1;33",
        logging.ERROR:    "1;31",
        logging.CRITICAL: "1;31",
    }

    def format(self, record: logging.LogRecord) -> str:
        ts  = self.formatTime(record, self.datefmt)
        msg = record.getMessage()
        if _USE_COLOR:
            code  = self._STYLES.get(record.levelno, "0")
            level = f"\033[{code}m{record.levelname:<8}\033[0m"
            ts    = f"\033[2m{ts}\033[0m"
        else:
            level = f"{record.levelname:<8}"
        return f"{ts}  {level}  {msg}"


_handler = logging.StreamHandler()
_handler.setFormatter(_ColorFormatter(datefmt="%H:%M:%S"))
logging.basicConfig(level=logging.INFO, handlers=[_handler])
log = logging.getLogger("truenas_migrate")