from fastapi import APIRouter, Depends, HTTPException
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy.future import select
from sqlalchemy import update
from pydantic import BaseModel
from typing import List

from packages.core.database import get_db
from packages.core.models import EntityReviewPool, EntityMapping

router = APIRouter(prefix="/entities", tags=["Entities"])

class ReviewTaskResponse(BaseModel):
    id: str
    source_name: str
    target_name: str
    target_entity_id: str
    similarity_score: float
    status: str

class ReviewDecisionRequest(BaseModel):
    task_id: str
    decision: str  # "APPROVED" or "REJECTED"

@router.get("/review-pool", response_model=List[ReviewTaskResponse])
async def get_review_pool(status: str = "PENDING", db: AsyncSession = Depends(get_db)):
    """
    获取待人工确认的企业实体合并任务。
    """
    stmt = select(EntityReviewPool).where(EntityReviewPool.status == status).limit(50)
    result = await db.execute(stmt)
    tasks = result.scalars().all()
    
    return [
        ReviewTaskResponse(
            id=t.id,
            source_name=t.source_name,
            target_name=t.target_name,
            target_entity_id=t.target_entity_id,
            similarity_score=t.similarity_score,
            status=t.status
        ) for t in tasks
    ]

@router.post("/review-decision")
async def make_review_decision(req: ReviewDecisionRequest, db: AsyncSession = Depends(get_db)):
    """
    提交运营审核决定。
    如果 APPROVED，则将 source_name 映射到 target_entity_id，并更新 review_pool 状态。
    如果 REJECTED，仅更新 review_pool 状态。
    """
    stmt = select(EntityReviewPool).where(EntityReviewPool.id == req.task_id)
    result = await db.execute(stmt)
    task = result.scalar_one_or_none()
    
    if not task:
        raise HTTPException(status_code=404, detail="Review task not found")
        
    if req.decision not in ["APPROVED", "REJECTED"]:
        raise HTTPException(status_code=400, detail="Invalid decision")
        
    task.status = req.decision
    
    if req.decision == "APPROVED":
        # 更新 mapping 表，将 source_name 的 standard_entity_id 指向 target_entity_id
        # 并将 is_manual 设为 1
        upd_stmt = update(EntityMapping).where(
            EntityMapping.original_name == task.source_name
        ).values(
            standard_entity_id=task.target_entity_id,
            standard_name=task.target_name,
            is_manual=1
        )
        await db.execute(upd_stmt)
        
    await db.commit()
    return {"status": "success", "task_id": req.task_id, "decision": req.decision}