# SPDX-License-Identifier: Apache-2.0
# SPDX-FileCopyrightText: Copyright contributors to the vLLM project

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

from vllm.engine.protocol import EngineClient
from vllm.entrypoints.serve.tokenize.serving import ServingTokenization
from vllm.logger import init_logger
from vllm.version import __version__ as VLLM_VERSION

router = APIRouter()

logger = init_logger(__name__)


def base(request: Request) -> ServingTokenization:
    # Reuse the existing instance
    return tokenization(request)


def tokenization(request: Request) -> ServingTokenization:
    return request.app.state.serving_tokenization


def engine_client(request: Request) -> EngineClient:
    return request.app.state.engine_client


@router.get("/load")
async def get_server_load_metrics(request: Request):
    # This endpoint returns the current server load metrics.
    # It tracks requests utilizing the GPU from the following routes:
    # - /v1/responses
    # - /v1/responses/{response_id}
    # - /v1/responses/{response_id}/cancel
    # - /v1/messages
    # - /v1/chat/completions
    # - /v1/completions
    # - /v1/audio/transcriptions
    # - /v1/audio/translations
    # - /v1/embeddings
    # - /pooling
    # - /classify
    # - /score
    # - /v1/score
    # - /rerank
    # - /v1/rerank
    # - /v2/rerank
    return JSONResponse(content={"server_load": request.app.state.server_load_metrics})


@router.get("/version")
async def show_version():
    ver = {"version": VLLM_VERSION}
    return JSONResponse(content=ver)


@router.get("/kv_event_sources")
async def kv_event_sources(raw_request: Request):
    """KV-event publisher config per DP rank; empty on render-only servers."""
    client: EngineClient | None = raw_request.app.state.engine_client
    return client.get_kv_event_sources() if client is not None else {}