"""Alerting API endpoints."""

from __future__ import annotations

from flask import Blueprint, Response, request

from utils.alerts import get_alert_manager
from utils.responses import api_error, api_success
from utils.sse import sse_stream_fanout

alerts_bp = Blueprint("alerts", __name__, url_prefix="/alerts")


@alerts_bp.route("/rules", methods=["GET"])
def list_rules():
    manager = get_alert_manager()
    include_disabled = request.args.get("all") in ("1", "true", "yes")
    return api_success(data={"rules": manager.list_rules(include_disabled=include_disabled)})


@alerts_bp.route("/rules", methods=["POST"])
def create_rule():
    data = request.get_json() or {}
    if not isinstance(data.get("match", {}), dict):
        return api_error("match must be a JSON object", 400)

    manager = get_alert_manager()
    rule_id = manager.add_rule(data)
    return api_success(data={"rule_id": rule_id})


@alerts_bp.route("/rules/<int:rule_id>", methods=["PUT", "PATCH"])
def update_rule(rule_id: int):
    data = request.get_json() or {}
    manager = get_alert_manager()
    ok = manager.update_rule(rule_id, data)
    if not ok:
        return api_error("Rule not found or no changes", 404)
    return api_success()


@alerts_bp.route("/rules/<int:rule_id>", methods=["DELETE"])
def delete_rule(rule_id: int):
    manager = get_alert_manager()
    ok = manager.delete_rule(rule_id)
    if not ok:
        return api_error("Rule not found", 404)
    return api_success()


@alerts_bp.route("/events", methods=["GET"])
def list_events():
    manager = get_alert_manager()
    limit = request.args.get("limit", default=100, type=int)
    mode = request.args.get("mode")
    severity = request.args.get("severity")
    events = manager.list_events(limit=limit, mode=mode, severity=severity)
    return api_success(data={"events": events})


@alerts_bp.route("/stream", methods=["GET"])
def stream_alerts() -> Response:
    manager = get_alert_manager()
    response = Response(
        sse_stream_fanout(
            source_queue=manager._queue,
            channel_key="alerts",
            timeout=1.0,
            keepalive_interval=30.0,
        ),
        mimetype="text/event-stream",
    )
    response.headers["Cache-Control"] = "no-cache"
    response.headers["X-Accel-Buffering"] = "no"
    response.headers["Connection"] = "keep-alive"
    return response