from fastapi import APIRouter, Depends, Request
from fastapi.responses import HTMLResponse
from sqlalchemy.orm import Session
from app.database import get_db
from app.models import PositionSnapshot
from app.engine.game_theory import net_position, net_pnl, format_pnl

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

INSTITUTIONS = ["中信期货", "高盛期货", "国泰君安期货", "华泰期货", "东证期货", "银河期货"]


@router.get("/", response_class=HTMLResponse)
def analysis_page(request: Request, db: Session = Depends(get_db)):
    latest_snap = (
        db.query(PositionSnapshot.date)
        .order_by(PositionSnapshot.date.desc())
        .first()
    )

    if not latest_snap:
        template = request.app.state.templates.get_template("analysis.html")
        return HTMLResponse(
            template.render(request=request, active_nav="analysis", rows=[], latest_date=None)
        )

    latest_date = latest_snap[0]
    current_price = 913  # TODO: fetch from daily_bars or akshare

    rows = []
    totals = {"long_pos": 0, "short_pos": 0, "net_pos": 0, "pnl": 0.0}
    total_net_short = 0
    pnl_sum = 0.0

    for inst in INSTITUTIONS:
        long = (
            db.query(PositionSnapshot)
            .filter(
                PositionSnapshot.institution == inst,
                PositionSnapshot.direction == "long",
                PositionSnapshot.date == latest_date,
            )
            .first()
        )
        short = (
            db.query(PositionSnapshot)
            .filter(
                PositionSnapshot.institution == inst,
                PositionSnapshot.direction == "short",
                PositionSnapshot.date == latest_date,
            )
            .first()
        )

        long_pos = long.position if long else 0
        short_pos = short.position if short else 0
        long_cost = long.avg_cost if long else 0
        short_cost = short.avg_cost if short else 0

        np = net_position(long_pos, short_pos)
        pnl = 0.0
        if np < 0:
            pnl = net_pnl(np, short_cost, current_price)
        elif np > 0:
            pnl = net_pnl(np, long_cost, current_price)

        totals["long_pos"] += long_pos
        totals["short_pos"] += short_pos
        totals["net_pos"] += np
        pnl_sum += pnl
        if np < 0:
            total_net_short += abs(np)

        rows.append({
            "institution": inst,
            "long_pos": f"{long_pos / 10000:.1f}万" if long_pos else "—",
            "short_pos": f"{short_pos / 10000:.1f}万" if short_pos else "—",
            "long_cost": f"{long_cost:.2f}" if long_cost else "—",
            "short_cost": f"{short_cost:.2f}" if short_cost else "—",
            "net_pos": f"净{'多' if np > 0 else '空'} {abs(np) / 10000:.1f}万",
            "pnl": format_pnl(pnl),
            "pnl_raw": pnl,
        })

    template = request.app.state.templates.get_template("analysis.html")
    return HTMLResponse(
        template.render(
            request=request,
            active_nav="analysis",
            rows=rows,
            totals={
                "long_pos": f"{totals['long_pos'] / 10000:.1f}万",
                "short_pos": f"{totals['short_pos'] / 10000:.1f}万",
                "net_pos": f"净{'多' if totals['net_pos'] > 0 else '空'} {abs(totals['net_pos']) / 10000:.1f}万",
                "pnl": format_pnl(pnl_sum),
            },
            latest_date=latest_date.strftime("%Y-%m-%d"),
            current_price=current_price,
            total_net_short=f"{total_net_short / 10000:.1f}万",
            total_pnl=format_pnl(pnl_sum),
        )
    )