from __future__ import annotations

import re
import secrets
import string
import time
from typing import Any

from flask import jsonify, request

from ..keycloak import admin_client
from ..rate_limit import rate_limit_allow
from .. import settings


def _extract_request_payload() -> tuple[str, str, str]:
    payload = request.get_json(silent=True) or {}
    username = (payload.get("username") or "").strip()
    email = (payload.get("email") or "").strip()
    note = (payload.get("note") or "").strip()
    return username, email, note


def _random_request_code(username: str) -> str:
    suffix = "".join(secrets.choice(string.ascii_uppercase + string.digits) for _ in range(10))
    return f"{username}~{suffix}"


def register(app) -> None:
    @app.route("/api/access/request", methods=["POST"])
    def request_access() -> Any:
        if not settings.ACCESS_REQUEST_ENABLED:
            return jsonify({"error": "request access disabled"}), 503
        if not admin_client().ready():
            return jsonify({"error": "server not configured"}), 503

        ip = request.remote_addr or "unknown"
        if not rate_limit_allow(ip):
            return jsonify({"error": "rate limited"}), 429

        username, email, note = _extract_request_payload()
        if not username:
            return jsonify({"error": "username is required"}), 400

        if len(username) < 3 or len(username) > 32:
            return jsonify({"error": "username must be 3-32 characters"}), 400
        if not re.fullmatch(r"[a-zA-Z0-9._-]+", username):
            return jsonify({"error": "username contains invalid characters"}), 400
        if email and "@" not in email:
            return jsonify({"error": "invalid email"}), 400

        if admin_client().find_user(username):
            return jsonify({"error": "username already exists"}), 409

        request_code = _random_request_code(username)
        attrs: dict[str, Any] = {
            "access_request_code": [request_code],
            "access_request_status": ["pending"],
            "access_request_note": [note] if note else [""],
            "access_request_created_at": [str(int(time.time()))],
            "access_request_contact_email": [email] if email else [""],
        }

        user_payload: dict[str, Any] = {"username": username, "enabled": False, "attributes": attrs}
        if email:
            user_payload["email"] = email
            user_payload["emailVerified"] = False

        try:
            user_id = admin_client().create_user(user_payload)
        except Exception:
            return jsonify({"error": "failed to submit request"}), 502

        return jsonify({"ok": True, "id": user_id, "request_code": request_code})

    @app.route("/api/access/request/status", methods=["POST"])
    def request_access_status() -> Any:
        if not settings.ACCESS_REQUEST_ENABLED:
            return jsonify({"error": "request access disabled"}), 503
        if not admin_client().ready():
            return jsonify({"error": "server not configured"}), 503

        ip = request.remote_addr or "unknown"
        if not rate_limit_allow(ip):
            return jsonify({"error": "rate limited"}), 429

        payload = request.get_json(silent=True) or {}
        code = (payload.get("request_code") or payload.get("code") or "").strip()
        if not code:
            return jsonify({"error": "request_code is required"}), 400

        username = (payload.get("username") or "").strip()
        if not username:
            if "~" not in code:
                return jsonify({"error": "invalid request code"}), 400
            username = code.split("~", 1)[0].strip()
        if not username:
            return jsonify({"error": "invalid request code"}), 400

        user = admin_client().find_user(username)
        if not user:
            return jsonify({"error": "not found"}), 404

        attrs = user.get("attributes") or {}
        if not isinstance(attrs, dict):
            return jsonify({"error": "not found"}), 404

        stored = attrs.get("access_request_code") or [""]
        stored_code = stored[0] if isinstance(stored, list) and stored else (stored if isinstance(stored, str) else "")
        if stored_code != code:
            return jsonify({"error": "not found"}), 404

        status = attrs.get("access_request_status") or [""]
        status_value = (
            status[0] if isinstance(status, list) and status else (status if isinstance(status, str) else "")
        )

        return jsonify({"ok": True, "status": status_value or "unknown"})