# /opt/docker/dev/service_finder/backend/app/api/v1/endpoints/reports.py
"""
Reports endpoints — Zombie API Cleanup.
Replaced raw SQL (FROM vehicle.vehicle_expenses) with SQLAlchemy ORM queries
using fleet_finance.asset_costs (AssetCost) + CostCategory.
"""
from fastapi import APIRouter, Depends, HTTPException
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy import select, func, desc
from sqlalchemy.orm import selectinload
from app.api.deps import get_db, get_current_user
from app.models.fleet_finance import AssetCost, CostCategory
from app.models.identity import User

router = APIRouter()


@router.get("/summary/{vehicle_id}")
async def get_vehicle_summary(
    vehicle_id: str,
    db: AsyncSession = Depends(get_db),
    current_user: User = Depends(get_current_user)
):
    """
    Összesített jelentés egy járműhöz: kategóriánkénti költségek.
    Uses fleet_finance.asset_costs (AssetCost) joined with CostCategory.
    """
    # Aggregate costs by category using ORM
    stmt = (
        select(
            CostCategory.name.label("category"),
            func.sum(AssetCost.amount_gross).label("total_amount"),
            func.count(AssetCost.id).label("transaction_count"),
        )
        .join(CostCategory, AssetCost.category_id == CostCategory.id)
        .where(AssetCost.asset_id == vehicle_id)
        .group_by(CostCategory.name)
    )
    result = await db.execute(stmt)
    rows = result.all()

    total_cost = sum(float(row.total_amount) for row in rows) if rows else 0.0

    return {
        "vehicle_id": vehicle_id,
        "total_cost": total_cost,
        "breakdown": [
            {
                "category": row.category,
                "total_amount": float(row.total_amount),
                "transaction_count": row.transaction_count,
            }
            for row in rows
        ],
    }


@router.get("/trends/{vehicle_id}")
async def get_monthly_trends(
    vehicle_id: str,
    db: AsyncSession = Depends(get_db),
    current_user: User = Depends(get_current_user)
):
    """
    Visszaadja az utolsó 6 hónap költéseit havi bontásban.
    Uses fleet_finance.asset_costs (AssetCost) with date truncation.
    """
    # Monthly aggregation using ORM-compatible date truncation
    from sqlalchemy import text as sql_text

    stmt = (
        select(
            func.to_char(AssetCost.date, "YYYY-MM").label("month"),
            func.sum(AssetCost.amount_gross).label("monthly_total"),
        )
        .where(AssetCost.asset_id == vehicle_id)
        .group_by(sql_text("month"))
        .order_by(desc(sql_text("month")))
        .limit(6)
    )
    result = await db.execute(stmt)
    rows = result.all()

    return [
        {"month": row.month, "monthly_total": float(row.monthly_total)}
        for row in rows
    ]


@router.get("/summary/latest")
async def get_latest_summary(
    db: AsyncSession = Depends(get_db),
    current_user: User = Depends(get_current_user)
):
    """
    Returns a simple summary for the dashboard (mock data for now).
    This endpoint is called by the frontend dashboard.
    """
    # For now, return mock data to satisfy the frontend
    return {
        "total_vehicles": 4,
        "total_cost_this_month": 1250.50,
        "most_expensive_category": "Fuel",
        "trend": "down",
        "trend_percentage": -5.2,
    }