"""WireGuard tunnel management API blueprint.

Exposed at /api/wireguard/* and delegates to vacuum-walld.
"""

import logging

from flask import Blueprint, request

from daemon.client import BadRequest, NotFound, delete, get, patch, post
from daemon.iface import (
    DELETE_WIREGUARD_PEERS_REMOVE,
    GET_WIREGUARD_CONFIG,
    GET_WIREGUARD_PEER_STATUS,
    GET_WIREGUARD_PEERS,
    GET_WIREGUARD_STATUS,
    PATCH_WIREGUARD_CONFIG,
    POST_WIREGUARD_APPLY,
    POST_WIREGUARD_CONFIG,
    POST_WIREGUARD_DOWN,
    POST_WIREGUARD_GENERATE_CLIENT,
    POST_WIREGUARD_INITIALIZE,
    POST_WIREGUARD_PEERS_ADD,
)
from webui.api.common import _error, _ok

logger = logging.getLogger(__name__)
bp = Blueprint("wireguard", __name__)


@bp.route("/config", methods=["GET"])
def get_config_bp():
    """Get the current WireGuard configuration.

    Endpoint: GET /api/wireguard/config

    Returns:
        JSON response with the WireGuard config on success, or an error
        response on failure.
    """
    try:
        return _ok(get(GET_WIREGUARD_CONFIG))
    except RuntimeError as exc:
        logger.error("Failed to read WireGuard config: %s", exc)
        return _error(str(exc), 500)


@bp.route("/config", methods=["POST"])
def post_config():
    """Create or fully replace the WireGuard configuration.

    Endpoint: POST /api/wireguard/config

    Args:
        body: JSON body with the configuration. If an ``interface`` key
            is present, the private key will be stripped before forwarding.

    Returns:
        Success response on acceptance, 400 on validation failure, or 500
        on server error.
    """
    body = request.get_json(silent=True) or {}
    if not isinstance(body, dict):
        return _error("Request body must be a JSON object", 400)
    try:
        if "interface" in body:
            body = dict(body)
            body["interface"] = dict(body["interface"])
            body["interface"].pop("private_key", None)
        post(POST_WIREGUARD_CONFIG, body)
        return _ok(None)
    except BadRequest as exc:
        logger.info("WireGuard config save rejected: %s", exc)
        return _error(str(exc), 400)
    except RuntimeError as exc:
        logger.error("Failed to save WireGuard config: %s", exc)
        return _error(str(exc), 500)


@bp.route("/config", methods=["PATCH"])
def patch_config():
    """Partially update the WireGuard configuration.

    Endpoint: PATCH /api/wireguard/config

    Args:
        body: JSON body with the fields to update. If an ``interface``
            key is present, the private key will be stripped before forwarding.

    Returns:
        Success response on acceptance, 400 on validation failure, or 500
        on server error.
    """
    body = request.get_json(silent=True) or {}
    if not isinstance(body, dict):
        return _error("Request body must be a JSON object", 400)
    try:
        if "interface" in body:
            body = dict(body)
            body["interface"] = dict(body["interface"])
            body["interface"].pop("private_key", None)
        patch(PATCH_WIREGUARD_CONFIG, body)
        logger.info("WireGuard config patched: %s", sorted(body.keys()))
        return _ok(None)
    except BadRequest as exc:
        logger.info("WireGuard config patch rejected: %s", exc)
        return _error(str(exc), 400)
    except RuntimeError as exc:
        logger.error("Failed to patch WireGuard config: %s", exc)
        return _error(str(exc), 500)


@bp.route("/apply", methods=["POST"])
def apply_bp():
    """Apply the current WireGuard configuration to the live tunnel.

    Endpoint: POST /api/wireguard/apply

    Returns:
        Success response on acceptance, or 500 on server error.
    """
    try:
        post(POST_WIREGUARD_APPLY)
        logger.info("WireGuard tunnel applied via API")
        return _ok(None)
    except RuntimeError as exc:
        logger.error("Failed to apply WireGuard config: %s", exc)
        return _error(str(exc), 500)


@bp.route("/up", methods=["POST"])
def up_bp():
    """Bring the WireGuard tunnel interface up.

    Endpoint: POST /api/wireguard/up

    Returns:
        Success response on acceptance, or 500 on server error.
    """
    try:
        post(POST_WIREGUARD_APPLY)
        logger.info("WireGuard tunnel started via API")
        return _ok(None)
    except RuntimeError as exc:
        logger.error("Failed to start WireGuard tunnel: %s", exc)
        return _error(str(exc), 500)


@bp.route("/down", methods=["POST"])
def down_bp():
    """Bring the WireGuard tunnel interface down.

    Endpoint: POST /api/wireguard/down

    Returns:
        Success response on acceptance, or 500 on server error.
    """
    try:
        post(POST_WIREGUARD_DOWN)
        logger.info("WireGuard tunnel brought down via API")
        return _ok(None)
    except RuntimeError as exc:
        logger.error("Failed to bring down WireGuard tunnel: %s", exc)
        return _error(str(exc), 500)


@bp.route("/status", methods=["GET"])
def status_bp():
    """Get the current WireGuard tunnel status.

    Endpoint: GET /api/wireguard/status

    Returns:
        JSON response with the tunnel status on success, or an error
        response on failure.
    """
    try:
        return _ok(get(GET_WIREGUARD_STATUS))
    except RuntimeError as exc:
        logger.error("Failed to get WireGuard status: %s", exc)
        return _error(str(exc), 500)


@bp.route("/initialize", methods=["POST"])
def initialize_bp():
    """Initialize WireGuard for first-time use.

    Endpoint: POST /api/wireguard/initialize

    Returns:
        Success response on acceptance, or 500 on server error.
    """
    try:
        post(POST_WIREGUARD_INITIALIZE)
        logger.info("WireGuard initialized via API")
        return _ok(None)
    except RuntimeError as exc:
        logger.error("Failed to initialize WireGuard: %s", exc)
        return _error(str(exc), 500)


@bp.route("/peers", methods=["POST"])
def add_peer_bp():
    """Add a new peer to the WireGuard configuration.

    Endpoint: POST /api/wireguard/peers

    Args:
        name: Peer display name (required).
        endpoint: Optional peer endpoint address.
        allowed_ips: Optional list of allowed IP CIDRs.
        persistent_keepalive: Optional keepalive interval in seconds.
        preshared_key: Optional pre-shared key in hex.

    Returns:
        JSON response with the created peer on success, 400 on validation
        failure, or 500 on server error.
    """
    body = request.get_json(silent=True) or {}
    name = body.get("name", "").strip()
    if not name:
        return _error("'name' is required", 400)
    try:
        peer = post(
            POST_WIREGUARD_PEERS_ADD,
            {
                "name": name,
                "endpoint": body.get("endpoint"),
                "allowed_ips": body.get("allowed_ips", []),
                "persistent_keepalive": body.get("persistent_keepalive"),
                "preshared_key": body.get("preshared_key"),
            },
        )
        logger.info("WireGuard peer '%s' added via API", name)
        return _ok(peer)
    except BadRequest as exc:
        logger.info("Add peer '%s' rejected: %s", name, exc)
        return _error(str(exc), 400)
    except RuntimeError as exc:
        logger.error("Failed to add peer '%s': %s", name, exc)
        return _error(str(exc), 500)


@bp.route("/peers/<name>", methods=["DELETE"])
def remove_peer_bp(name):
    """Remove a peer from the WireGuard configuration.

    Endpoint: DELETE /api/wireguard/peers/<name>

    Args:
        name: Peer name to remove (from URL path).

    Returns:
        Success response with peer name on removal, 404 if peer not found,
        or 500 on server error.
    """
    try:
        delete(DELETE_WIREGUARD_PEERS_REMOVE, {"name": name})
        logger.info("WireGuard peer '%s' removed via API", name)
        return _ok({"name": name})
    except NotFound as exc:
        logger.info("WireGuard peer '%s' not found: %s", name, exc)
        return _error(str(exc), 404)
    except RuntimeError as exc:
        logger.error("Failed to remove peer '%s': %s", name, exc)
        return _error(str(exc), 500)


@bp.route("/peers", methods=["GET"])
def peers_bp():
    """List all configured WireGuard peers.

    Endpoint: GET /api/wireguard/peers

    Returns:
        JSON response with the peers list on success, or an error response
        on failure.
    """
    try:
        return _ok(get(GET_WIREGUARD_PEERS))
    except RuntimeError as exc:
        logger.error("Failed to list WireGuard peers: %s", exc)
        return _error(str(exc), 500)


@bp.route("/peer-status", methods=["GET"])
def peer_status_bp():
    """Get real-time status information for all WireGuard peers.

    Endpoint: GET /api/wireguard/peer-status

    Returns:
        JSON response with peer status on success, or an error response
        on failure.
    """
    try:
        return _ok(get(GET_WIREGUARD_PEER_STATUS))
    except RuntimeError as exc:
        logger.error("Failed to get WireGuard peer status: %s", exc)
        return _error(str(exc), 500)


@bp.route("/generate-client", methods=["POST"])
def generate_client_bp():
    """Generate a WireGuard client configuration file for a peer.

    Endpoint: POST /api/wireguard/generate-client

    Args:
        name: Peer name (required).
        server_endpoint: Server endpoint address for the client config (required).

    Returns:
        JSON response with the generated config string on success, 404 if
        peer not found, 400 on validation failure, or 500 on server error.
    """
    body = request.get_json(silent=True) or {}
    name = body.get("name", "").strip()
    if not name:
        return _error("Field 'name' is required", 400)
    server_endpoint = body.get("server_endpoint", "")
    if not server_endpoint:
        return _error("Field 'server_endpoint' is required", 400)
    try:
        result = post(
            POST_WIREGUARD_GENERATE_CLIENT,
            {
                "name": name,
                "server_endpoint": server_endpoint,
            },
        )
        logger.info("Client config generated for peer '%s' via API", name)
        return _ok({"config": result.get("config", "")})
    except NotFound as exc:
        logger.info("Peer '%s' not found for client config: %s", name, exc)
        return _error(str(exc), 404)
    except RuntimeError as exc:
        logger.error("Failed to generate client config for '%s': %s", name, exc)
        return _error(str(exc), 500)