"""Detect primary nginx site domain on remote Baota/generic hosts."""

from __future__ import annotations

import shlex


def build_nginx_domain_detect_command(*, target_hint: str = "") -> str:
    """Build remote shell snippet that prints one site hostname to stdout.

    Lookup order:
    1. Baota vhost basename ``/www/server/panel/vhost/nginx/{domain}.conf``
    2. ``server_name`` in Baota vhosts and generic nginx dirs
    Prefer *target_hint* when it matches a candidate.
    """
    hint = (target_hint or "").strip().lower()
    qhint = shlex.quote(hint) if hint else "''"
    return (
        f"TARGET_HINT={qhint}; "
        "_is_domain() { "
        'local h="${1,,}"; '
        '[[ "$h" == *.* ]] || return 1; '
        '[[ "$h" =~ ^[0-9]+(\\.[0-9]+){3}$ ]] && return 1; '
        'case "$h" in default|0.default|0.site_total|phpmyadmin|localhost|127.0.0.1|_*|*.local) return 1 ;; esac; '
        "return 0; "
        "}; "
        "_pick() { "
        'local best=""; '
        "for h in \"$@\"; do "
        '[ -n "$h" ] || continue; '
        "_is_domain \"$h\" || continue; "
        'if [ -n "$TARGET_HINT" ] && [ "$h" = "$TARGET_HINT" ]; then echo "$h"; return 0; fi; '
        'if [ -z "$best" ] || [[ "$h" < "$best" ]]; then best="$h"; fi; '
        "done; "
        '[ -n "$best" ] && echo "$best"; '
        "}; "
        "cands=(); "
        'BT="/www/server/panel/vhost/nginx"; '
        'if [ -d "$BT" ]; then '
        'for f in "$BT"/*.conf; do '
        '[ -f "$f" ] || continue; '
        'base=$(basename "$f" .conf); '
        "_is_domain \"$base\" && cands+=(\"$base\"); "
        "done; "
        "fi; "
        'if [ ${#cands[@]} -gt 0 ]; then _pick "${cands[@]}"; exit 0; fi; '
        "_names_from() { "
        'grep -E "^[[:space:]]*server_name[[:space:]]" "$1" 2>/dev/null '
        "| head -1 | sed 's/.*server_name[[:space:]]\\+//;s/;//;s/\\$//g'; "
        "}; "
        'for dir in "$BT" /etc/nginx/sites-enabled /etc/nginx/conf.d; do '
        '[ -d "$dir" ] || continue; '
        'for f in "$dir"/*; do '
        '[ -f "$f" ] || continue; '
        'raw=$(_names_from "$f"); '
        'for token in $raw; do '
        'token="${token,,}"; '
        "_is_domain \"$token\" && cands+=(\"$token\"); "
        "done; "
        "done; "
        "done; "
        '_pick "${cands[@]}"'
    )