from fastapi import APIRouter, Depends, HTTPException, BackgroundTasks
from pydantic import BaseModel
from typing import Optional

from apps.api.dependencies.auth import get_api_key, get_current_user_tier
from apps.worker.export_tasks import export_data_task

router = APIRouter(prefix="/export", tags=["Export"])

class ExportRequest(BaseModel):
    hs_code: Optional[str] = None
    country: Optional[str] = None
    start_date: str
    end_date: str
    email: str

@router.post("/")
async def request_async_export(
    req: ExportRequest, 
    api_key: str = Depends(get_api_key),
    tier: str = Depends(get_current_user_tier)
):
    """
    提交异步导出任务。
    根据用户的层级 (tier)，可以限制导出的数据量或范围。
    """
    if tier == "trial":
        raise HTTPException(status_code=403, detail="Trial users cannot export data. Please upgrade your plan.")
        
    # 将任务推入 Celery 队列
    task = export_data_task.delay(
        query_params={
            "hs_code": req.hs_code,
            "country": req.country,
            "start_date": req.start_date,
            "end_date": req.end_date
        },
        user_email=req.email
    )
    
    return {
        "message": "Export task submitted successfully.",
        "task_id": task.id,
        "tier": tier
    }

@router.get("/status/{task_id}")
async def get_export_status(task_id: str, api_key: str = Depends(get_api_key)):
    """
    查询异步导出任务状态。
    """
    from packages.core.celery_app import celery_app
    task = celery_app.AsyncResult(task_id)
    
    if task.state == 'PENDING':
        return {"task_id": task_id, "status": "Pending"}
    elif task.state == 'SUCCESS':
        return {"task_id": task_id, "status": "Completed", "result": task.result}
    elif task.state == 'FAILURE':
        return {"task_id": task_id, "status": "Failed", "error": str(task.info)}
    else:
        return {"task_id": task_id, "status": task.state}