"""系统监控接口。"""

from __future__ import annotations

from fastapi import APIRouter, Request
from fastapi.responses import HTMLResponse, JSONResponse, Response

from ..schemas.system import SystemStatus
from ..services.system_service import SystemService
from ..views.system_status_html import render as render_status_html

router = APIRouter(prefix="/api/system", tags=["system"])


def _wants_html(request: Request, fmt: str | None) -> bool:
    if fmt == "json":
        return False
    if fmt == "html":
        return True
    accept = request.headers.get("accept", "").lower()
    return "text/html" in accept and "application/json" not in accept


@router.get(
    "/status",
    summary="主机资源状态（HTML 或 JSON）",
    description=(
        "返回 CPU、内存、磁盘的实时使用情况（数据来源 psutil）。\n\n"
        "**内容协商**：浏览器（`Accept: text/html`）返回 HTML 页面，API 客户端返回 JSON。"
        "可用 `?format=html` / `?format=json` 强制指定。"
    ),
    response_model=SystemStatus,
    responses={200: {"content": {"application/json": {}, "text/html": {"schema": {"type": "string"}}}}},
)
def get_status(request: Request, format: str | None = None) -> Response:
    status = SystemService().get_status()
    if _wants_html(request, format):
        return HTMLResponse(render_status_html(status))
    return JSONResponse(status.model_dump(mode="json"))