import hashlib
import os
import pathlib
import re
import socket
from typing import Optional

from .constants import HTTPS_PORTS


def ensure_dir(path: pathlib.Path) -> None:
    path.mkdir(parents=True, exist_ok=True)


def sha256_file(path: pathlib.Path) -> str:
    h = hashlib.sha256()
    with path.open("rb") as f:
        for chunk in iter(lambda: f.read(1024 * 1024), b""):
            h.update(chunk)
    return h.hexdigest()


def normalize_path(path: Optional[str]) -> str:
    """Normalize optional service path. Empty -> ''. Ensure leading slash."""
    if not path:
        return ""
    p = str(path).strip()
    if not p:
        return ""
    if not p.startswith("/"):
        p = "/" + p
    return p


def default_host() -> str:
    """Return preferred hostname (append .local if bare)."""
    host = socket.gethostname()
    if "." not in host:
        host = f"{host}.local"
    return host


def detect_https(host: str, port: int) -> bool:
    """Heuristic: known HTTPS ports or .local certs."""
    return int(port) in HTTPS_PORTS or host.lower().endswith(".local") or host.lower() == "pikit"


def port_online(host: str, port: int) -> bool:
    try:
        with socket.create_connection((host, int(port)), timeout=1.5):
            return True
    except Exception:
        return False


def reboot_required() -> bool:
    return pathlib.Path("/run/reboot-required").exists()


def strip_comments(text: str) -> str:
    """Remove // and # line comments for safer parsing."""
    lines = []
    for ln in text.splitlines():
        l = ln.strip()
        if l.startswith("//") or l.startswith("#"):
            continue
        lines.append(ln)
    return "\n".join(lines)


def validate_time(val: str, default: str) -> str:
    if not val:
        return default
    m = re.match(r"^(\d{1,2}):(\d{2})$", val.strip())
    if not m:
        return default
    h, mi = int(m.group(1)), int(m.group(2))
    if 0 <= h < 24 and 0 <= mi < 60:
        return f"{h:02d}:{mi:02d}"
    return default