"""Contact masking.

Phone numbers and email addresses in listing bodies / messages are masked
for low-trust senders to push communication through the in-site channel.
Unmasked only once sender reaches TrustTier.trusted or verified_email=True.

Masking is a display-layer concern: raw body stored as-is; masked on render.
For the *sending* side we heuristic-flag high-contact-density messages so
moderators can spot scraping attempts.
"""
import re
from datetime import datetime
from app.models.enums import TrustTier
from app.services.settings import get_setting

# patterns
_PHONE_RE = re.compile(
    r"(\+?1[\s\-.]?)?"
    r"(\(?\d{3}\)?[\s\-.])"
    r"\d{3}[\s\-.]\d{4}"
)
_EMAIL_RE = re.compile(r"[A-Za-z0-9._%+\-]+@[A-Za-z0-9.\-]+\.[A-Za-z]{2,}")
_URL_RE   = re.compile(r"https?://\S+|www\.\S+", re.I)


def contact_revealed(user) -> bool:
    """True when this user's contact info may be shown unmasked."""
    if user is None:
        return False
    if not (user.email_verified and
            user.trust_tier in (TrustTier.trusted, TrustTier.verified)):
        return False
    gate_days = get_setting("new_user_trust_gate_days", 0)
    if gate_days and user.created_at:
        if (datetime.utcnow() - user.created_at).days < gate_days:
            return False
    return True


def mask_body(text: str, reveal: bool = False) -> str:
    """Optionally mask phones, emails, and URLs in a block of text."""
    if reveal or not text:
        return text
    text = _PHONE_RE.sub("[phone hidden]", text)
    text = _EMAIL_RE.sub("[email hidden]", text)
    text = _URL_RE.sub("[link hidden]", text)
    return text


def contact_density(text: str) -> int:
    """Count how many contact signals appear in text (for heuristic flagging)."""
    if not text:
        return 0
    return (len(_PHONE_RE.findall(text))
            + len(_EMAIL_RE.findall(text))
            + len(_URL_RE.findall(text)))