"""Keycloak admin API client.

Provides a KeycloakAdmin class for managing realms, OIDC clients, and users
via the Keycloak REST API. Used by setup_keycloak_integration.py scripts.
"""

import json
import urllib.error
import urllib.parse
import urllib.request


class KeycloakAdmin:
    """Client for the Keycloak Admin REST API."""

    def __init__(self, base_url: str, admin_user: str, admin_password: str):
        self.base_url = base_url.rstrip("/")
        self.admin_user = admin_user
        self.admin_password = admin_password

    def _request(self, method: str, path: str, *,
                 data: dict | None = None,
                 headers: dict | None = None,
                 timeout: int = 30) -> tuple[int, dict | list | None]:
        """Make an HTTP request, return (status_code, parsed_json)."""
        url = f"{self.base_url}{path}"
        body = json.dumps(data).encode() if data is not None else None
        req = urllib.request.Request(url, data=body, method=method)
        req.add_header("Content-Type", "application/json")
        for k, v in (headers or {}).items():
            req.add_header(k, v)
        try:
            with urllib.request.urlopen(req, timeout=timeout) as resp:
                raw = resp.read()
                if not raw:
                    return resp.getcode(), None
                return resp.getcode(), json.loads(raw)
        except urllib.error.HTTPError as e:
            try:
                raw = e.read().decode(errors="replace")
                return e.code, json.loads(raw) if raw.strip() else None
            except Exception:
                return e.code, None

    def get_admin_token(self) -> str:
        """Get an admin access token from the master realm."""
        url = f"{self.base_url}/realms/master/protocol/openid-connect/token"
        body = urllib.parse.urlencode({
            "username": self.admin_user,
            "password": self.admin_password,
            "grant_type": "password",
            "client_id": "admin-cli",
        }).encode()
        req = urllib.request.Request(url, data=body, method="POST")
        req.add_header("Content-Type", "application/x-www-form-urlencoded")
        with urllib.request.urlopen(req, timeout=30) as resp:
            data = json.loads(resp.read())
        return data["access_token"]

    def _auth_headers(self) -> dict:
        token = self.get_admin_token()
        return {"Authorization": f"Bearer {token}"}

    def ensure_realm(self, realm: str) -> None:
        """Create a realm if it doesn't exist."""
        print(f"=== Ensure Keycloak realm '{realm}' ===", flush=True)
        headers = self._auth_headers()
        status, _ = self._request(
            "GET", f"/admin/realms/{realm}", headers=headers)
        if status == 404:
            status, _ = self._request("POST", "/admin/realms", data={
                "realm": realm,
                "enabled": True,
                "registrationAllowed": False,
            }, headers=headers)
            print(f"  Created realm '{realm}'", flush=True)
        else:
            print(f"  Realm '{realm}' already exists, skipping", flush=True)

    def ensure_client(self, realm: str, client_id: str,
                      redirect_uris: list[str],
                      web_origins: list[str]) -> tuple[str, str]:
        """Create an OIDC client if needed, return (client_uuid, client_secret)."""
        print(f"=== Ensure OIDC client '{client_id}' ===", flush=True)
        headers = self._auth_headers()

        # Check if client exists
        status, data = self._request(
            "GET",
            f"/admin/realms/{realm}/clients?clientId={client_id}",
            headers=headers,
        )
        if data and len(data) > 0:
            client_uuid = data[0]["id"]
            print(f"  Client '{client_id}' already exists, skipping", flush=True)
        else:
            status, _ = self._request(
                "POST", f"/admin/realms/{realm}/clients",
                data={
                    "clientId": client_id,
                    "enabled": True,
                    "protocol": "openid-connect",
                    "publicClient": False,
                    "standardFlowEnabled": True,
                    "directAccessGrantsEnabled": True,
                    "serviceAccountsEnabled": True,
                    "authorizationServicesEnabled": True,
                    "redirectUris": redirect_uris,
                    "webOrigins": web_origins,
                    "attributes": {"pkce.code.challenge.method": ""},
                },
                headers=headers,
            )
            print(f"  Created client '{client_id}'", flush=True)

            # Re-fetch to get UUID
            headers = self._auth_headers()
            _, data = self._request(
                "GET",
                f"/admin/realms/{realm}/clients?clientId={client_id}",
                headers=headers,
            )
            client_uuid = data[0]["id"]

        # Get client secret
        headers = self._auth_headers()
        _, secret_data = self._request(
            "GET",
            f"/admin/realms/{realm}/clients/{client_uuid}/client-secret",
            headers=headers,
        )
        client_secret = secret_data["value"]
        print(f"  Client UUID: {client_uuid}", flush=True)
        print(f"  Client secret: {client_secret}", flush=True)
        return client_uuid, client_secret

    def ensure_user(self, realm: str, username: str, email: str,
                    password: str, *,
                    first_name: str = "Test",
                    last_name: str = "User") -> str:
        """Create a user if needed, set password. Returns user ID."""
        print(f"=== Ensure user '{username}' ===", flush=True)
        headers = self._auth_headers()

        _, data = self._request(
            "GET",
            f"/admin/realms/{realm}/users?username={username}",
            headers=headers,
        )
        if data and len(data) > 0:
            user_id = data[0]["id"]
            print(f"  User '{username}' exists ({user_id}), resetting password",
                  flush=True)
            headers = self._auth_headers()
            self._request(
                "PUT",
                f"/admin/realms/{realm}/users/{user_id}/reset-password",
                data={
                    "type": "password",
                    "value": password,
                    "temporary": False,
                },
                headers=headers,
            )
        else:
            headers = self._auth_headers()
            self._request(
                "POST", f"/admin/realms/{realm}/users",
                data={
                    "username": username,
                    "email": email,
                    "firstName": first_name,
                    "lastName": last_name,
                    "emailVerified": True,
                    "enabled": True,
                    "credentials": [{
                        "type": "password",
                        "value": password,
                        "temporary": False,
                    }],
                },
                headers=headers,
            )
            print(f"  Created user '{username}'", flush=True)

            # Re-fetch to get ID
            headers = self._auth_headers()
            _, data = self._request(
                "GET",
                f"/admin/realms/{realm}/users?username={username}",
                headers=headers,
            )
            user_id = data[0]["id"]

        return user_id