"""
Correlation analysis API endpoints.
"""
from fastapi import APIRouter, Depends, HTTPException
from sqlalchemy.orm import Session

from app.core.database import get_db
from app.api.deps import CurrentUser
from app.schemas.correlation import (
    CorrelationMatrixRequest,
    CorrelationMatrixResponse,
    DiversificationResponse,
    HighCorrelationPair,
)
from app.services.correlation import CorrelationService

router = APIRouter(prefix="/api/correlation", tags=["correlation"])


@router.post("/matrix", response_model=CorrelationMatrixResponse)
async def calculate_correlation_matrix(
    request: CorrelationMatrixRequest,
    current_user: CurrentUser,
    db: Session = Depends(get_db),
):
    """종목 간 수익률 상관 행렬 계산."""
    service = CorrelationService(db)
    result = service.get_correlation_data(request.stock_codes, request.period_days)

    return CorrelationMatrixResponse(
        stock_codes=result["stock_codes"],
        matrix=result["matrix"],
        high_correlation_pairs=[
            HighCorrelationPair(**p) for p in result["high_correlation_pairs"]
        ],
    )


@router.get("/portfolio/{portfolio_id}", response_model=DiversificationResponse)
async def get_portfolio_diversification(
    portfolio_id: int,
    current_user: CurrentUser,
    db: Session = Depends(get_db),
):
    """포트폴리오 분산 효과 점수 조회."""
    service = CorrelationService(db)

    try:
        score = service.calculate_portfolio_diversification(portfolio_id)
    except ValueError as e:
        raise HTTPException(status_code=404, detail=str(e))

    # Get holdings for correlation data
    from app.models.portfolio import Portfolio, PortfolioSnapshot

    portfolio = db.query(Portfolio).filter(
        Portfolio.id == portfolio_id,
        Portfolio.user_id == current_user.id,
    ).first()
    if not portfolio:
        raise HTTPException(status_code=404, detail="Portfolio not found")

    snapshot = (
        db.query(PortfolioSnapshot)
        .filter(PortfolioSnapshot.portfolio_id == portfolio_id)
        .order_by(PortfolioSnapshot.snapshot_date.desc())
        .first()
    )

    high_pairs = []
    stock_count = 0
    if snapshot and snapshot.holdings:
        tickers = [h.ticker for h in snapshot.holdings]
        stock_count = len(tickers)
        if len(tickers) >= 2:
            corr_data = service.get_correlation_data(tickers, period_days=60)
            high_pairs = [
                HighCorrelationPair(**p) for p in corr_data["high_correlation_pairs"]
            ]

    return DiversificationResponse(
        portfolio_id=portfolio_id,
        diversification_score=score,
        stock_count=stock_count,
        high_correlation_pairs=high_pairs,
    )