from fastapi import APIRouter, UploadFile, File, Query

from app.schemas.dataset import (
    DatasetPreviewResponse,
    DatasetUploadResponse,
    DatasetValidationResult,
)

router = APIRouter()


@router.post("/upload", response_model=DatasetUploadResponse)
async def upload_dataset(file: UploadFile = File(...)):
    """上传数据集文件（JSONL / CSV / Parquet / JSON）。"""
    return DatasetUploadResponse(
        id="placeholder",
        name=file.filename or "unknown",
        format="jsonl",
        record_count=0,
        file_path="",
        created_at="",
    )


@router.get("/{dataset_id}/preview", response_model=DatasetPreviewResponse)
async def preview_dataset(dataset_id: str, rows: int = Query(default=10, le=100)):
    """预览数据集前 N 行。"""
    return DatasetPreviewResponse(total_records=0, preview_rows=[], columns=[])


@router.post("/{dataset_id}/validate", response_model=DatasetValidationResult)
async def validate_dataset(dataset_id: str):
    """校验数据集格式和 Schema。"""
    return DatasetValidationResult(is_valid=True)


@router.get("/", response_model=list[DatasetUploadResponse])
async def list_datasets():
    """列出所有已上传数据集。"""
    return []


@router.delete("/{dataset_id}")
async def delete_dataset(dataset_id: str):
    """删除数据集。"""
    return {"status": "deleted"}