import logging
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy import select, delete
from datetime import datetime

from app.db.database import SessionLocal
from app.db.models import AccountStatus, Holding
from app.services.kis_client import kis_client

logger = logging.getLogger(__name__)

class SyncService:
    async def sync_account(self, db: AsyncSession):
        """
        Fetches balance from KIS and updates DB (AccountStatus & Holdings).
        Currently supports Domestic only.
        """
        logger.info("SyncService: Starting Account Sync...")
        try:
            # 1. Fetch Domestic Balance
            # kis_client.get_balance returns dict with 'output1', 'output2' or None
            res = await kis_client.get_balance("Domestic")
            if not res:
                logger.error("SyncService: Failed to fetch balance (API Error or No Data).")
                return

            # output1: Holdings List
            # output2: Account Summary
            output1 = res.get('output1', [])
            output2 = res.get('output2', [])
            
            # KIS API returns output2 as a LIST of 1 dict usually
            summary_data = output2[0] if output2 else {}
            
            # --- Update AccountStatus ---
            # Map KIS fields to AccountStatus model
            # tot_evlu_amt: 총평가금액 (Total Assets)
            # dnca_tot_amt: 예수금총액 (Buying Power)
            # evlu_pfls_smt_tl: 평가손익합계 (Daily Profit - approximation)
            # evlu_pfls_rt: 수익률
            
            total_assets = float(summary_data.get('tot_evlu_amt', 0) or 0)
            buying_power = float(summary_data.get('dnca_tot_amt', 0) or 0)
            daily_profit = float(summary_data.get('evlu_pfls_smt_tl', 0) or 0)
            
            # Calculate daily profit rate if not provided directly
            # profit_rate = float(summary_data.get('evlu_pfls_rt', 0)) # Sometimes available
            daily_profit_rate = 0.0
            if total_assets > 0:
                daily_profit_rate = (daily_profit / total_assets) * 100

            # Upsert AccountStatus (ID=1)
            stmt = select(AccountStatus).where(AccountStatus.id == 1)
            result = await db.execute(stmt)
            status = result.scalar_one_or_none()
            
            if not status:
                status = AccountStatus(id=1)
                db.add(status)
            
            status.totalAssets = total_assets
            status.buyingPower = buying_power
            status.dailyProfit = daily_profit
            status.dailyProfitRate = daily_profit_rate
            
            # --- Update Holdings ---
            # Strategy: Delete all existing holdings (refresh) or Upsert?
            # Refresh is safer to remove sold items.
            await db.execute(delete(Holding))
            
            for item in output1:
                # Map fields
                # pdno: 종목번호
                # prdt_name: 종목명
                # hldg_qty: 보유수량
                # pchs_avg_pric: 매입평균가격
                # prpr: 현재가
                # evlu_pfls_amt: 평가손익금액
                # evlu_pfls_rt: 평가손익율
                # evlu_amt: 평가금액
                
                code = item.get('pdno')
                if not code: continue
                
                h = Holding(
                    stockCode=code,
                    stockName=item.get('prdt_name', 'Unknown'),
                    quantity=int(item.get('hldg_qty', 0) or 0),
                    avgPrice=float(item.get('pchs_avg_pric', 0) or 0),
                    currentPrice=float(item.get('prpr', 0) or 0),
                    profit=float(item.get('evlu_pfls_amt', 0) or 0),
                    profitRate=float(item.get('evlu_pfls_rt', 0) or 0),
                    marketValue=float(item.get('evlu_amt', 0) or 0)
                )
                db.add(h)
                
            await db.commit()
            logger.info(f"SyncService: Account Sync Complete. Assets: {total_assets}, Holdings: {len(output1)}")
            
        except Exception as e:
            await db.rollback()
            logger.error(f"SyncService: Error during sync: {e}")

sync_service = SyncService()