from fastapi import APIRouter, HTTPException
from typing import Optional

from database import get_session
from models import Vehicle, FuelRecord
from schemas import DashboardData, FuelRecordItem


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


@router.get("/data", response_model=DashboardData)
def get_dashboard(vehicle_id: int):
    """获取仪表盘数据"""
    with get_session() as session:
        vehicle = (
            session.query(Vehicle)
            .filter(Vehicle.id == vehicle_id, Vehicle.is_deleted == False)
            .first()
        )
        if not vehicle:
            raise HTTPException(status_code=404, detail="Vehicle not found")

        # 获取所有未删除的加油记录
        fuel_records = (
            session.query(FuelRecord)
            .filter(FuelRecord.vehicle_id == vehicle_id, FuelRecord.is_deleted == False)
            .order_by(FuelRecord.date.asc())
            .all()
        )

        # 计算总里程
        if fuel_records:
            latest_mileage = max(r.mileage for r in fuel_records)
            total_mileage = latest_mileage - vehicle.initial_mileage
        else:
            total_mileage = 0

        # 计算总油费
        total_fuel_cost = sum(float(r.total_cost) for r in fuel_records)

        # 计算平均油耗（只算加满的记录）
        total_fuel_amount = sum(
            float(r.fuel_amount) for r in fuel_records if r.is_full_tank
        )
        avg_fuel_consumption = None
        if total_mileage > 0 and total_fuel_amount > 0:
            avg_fuel_consumption = round((total_fuel_amount / total_mileage) * 100, 2)

        # 获取最近5条加油记录（带油耗计算，排除已删除）
        recent_records = (
            session.query(FuelRecord)
            .filter(FuelRecord.vehicle_id == vehicle_id, FuelRecord.is_deleted == False)
            .order_by(FuelRecord.date.desc(), FuelRecord.mileage.desc())
            .limit(5)
            .all()
        )

        recent_fuel_records = []
        for record in recent_records:
            # 计算单次油耗
            fuel_consumption = None
            if record.is_full_tank:
                # 先找更早日期的记录
                prev_record = (
                    session.query(FuelRecord)
                    .filter(
                        FuelRecord.vehicle_id == vehicle_id,
                        FuelRecord.date < record.date,
                        FuelRecord.is_full_tank == True,
                        FuelRecord.is_deleted == False,
                    )
                    .order_by(FuelRecord.date.desc(), FuelRecord.mileage.desc())
                    .first()
                )

                # 如果没找到，找同一天更早的记录
                if not prev_record:
                    prev_record = (
                        session.query(FuelRecord)
                        .filter(
                            FuelRecord.vehicle_id == vehicle_id,
                            FuelRecord.date == record.date,
                            FuelRecord.mileage < record.mileage,
                            FuelRecord.is_full_tank == True,
                            FuelRecord.is_deleted == False,
                        )
                        .order_by(FuelRecord.mileage.desc())
                        .first()
                    )

                if prev_record:
                    mileage_diff = record.mileage - prev_record.mileage
                    if mileage_diff > 0:
                        fuel_consumption = round(
                            (float(record.fuel_amount) / mileage_diff) * 100, 2
                        )

            recent_fuel_records.append(
                FuelRecordItem(
                    id=record.id,
                    date=record.date,
                    mileage=record.mileage,
                    fuel_amount=float(record.fuel_amount),
                    total_cost=float(record.total_cost),
                    fuel_consumption=fuel_consumption,
                )
            )

        # 计算日均行程
        avg_daily_km = None
        if total_mileage > 0 and fuel_records:
            first_date = fuel_records[0].date  # 第一次加油日期（已按日期升序排序）
            last_date = fuel_records[-1].date  # 最后一次加油日期
            days = (last_date - first_date).days
            if days > 0:
                avg_daily_km = round(total_mileage / days, 1)

        return DashboardData(
            vehicle_id=vehicle_id,
            vehicle_name=vehicle.name,
            purchase_date=vehicle.purchase_date,
            total_mileage=total_mileage,
            total_fuel_cost=round(total_fuel_cost, 2),
            avg_fuel_consumption=avg_fuel_consumption,
            avg_daily_km=avg_daily_km,
            recent_fuel_records=recent_fuel_records,
        )