import uuid
from datetime import date
from typing import Optional
from fastapi import APIRouter, Depends, HTTPException, Query
from sqlalchemy.ext.asyncio import AsyncSession
from sqlalchemy import select
from app.database import get_db
from app.middleware.auth import get_current_user, require_any_role
from app.utils.timezone import parse_date
from app.utils.edit_log import compute_diff, append_entry, init_entry
from app.models.work_plan import WorkPlan
from app.models.customer import Customer
from app.models.user import User
from app.schemas.work_plan import WorkPlanCreate, WorkPlanUpdate, WorkPlanOut

router = APIRouter(prefix="/work-plans", tags=["WorkPlans"])


async def _enrich(wp: WorkPlan, db: AsyncSession) -> dict:
    cust = await db.execute(select(Customer.name).where(Customer.id == wp.customer_id))
    mgr = await db.execute(select(User.name).where(User.id == wp.manager_id))
    return {
        "id": str(wp.id),
        "customer_id": str(wp.customer_id),
        "customer_name": cust.scalar_one_or_none(),
        "plan_content": wp.plan_content,
        "plan_date": wp.plan_date,
        "manager_id": str(wp.manager_id),
        "manager_name": mgr.scalar_one_or_none(),
        "status": wp.status,
        "edit_log": wp.edit_log or [],
    }


@router.get("/")
async def list_work_plans(
    customer_id: Optional[str] = Query(None),
    current_user: dict = Depends(get_current_user),
    db: AsyncSession = Depends(get_db),
):
    query = select(WorkPlan)
    if current_user["role"] == "manager":
        query = query.where(WorkPlan.manager_id == uuid.UUID(current_user["user_id"]))
    if customer_id:
        query = query.where(WorkPlan.customer_id == uuid.UUID(customer_id))
    query = query.order_by(WorkPlan.plan_date.desc()).limit(200)
    result = await db.execute(query)
    return [await _enrich(w, db) for w in result.scalars().all()]


@router.post("/")
async def create_work_plan(
    data: WorkPlanCreate,
    current_user: dict = Depends(require_any_role),
    db: AsyncSession = Depends(get_db),
):
    wp = WorkPlan(
        customer_id=data.customer_id,
        plan_content=data.plan_content,
        plan_date=parse_date(data.plan_date),
        manager_id=data.manager_id if (current_user["role"] in ("director", "leader") and data.manager_id) else uuid.UUID(current_user["user_id"]),
        status=data.status,
    )
    init_entry(wp, current_user["name"])
    db.add(wp)
    await db.commit()
    await db.refresh(wp)
    return await _enrich(wp, db)


@router.put("/{plan_id}")
async def update_work_plan(
    plan_id: str, data: WorkPlanUpdate,
    current_user: dict = Depends(require_any_role),
    db: AsyncSession = Depends(get_db),
):
    result = await db.execute(select(WorkPlan).where(WorkPlan.id == plan_id))
    wp = result.scalar_one_or_none()
    if not wp:
        raise HTTPException(status_code=404, detail="Not found")
    if current_user["role"] == "manager" and str(wp.manager_id) != current_user["user_id"]:
        raise HTTPException(status_code=403, detail="Access denied")

    old_snapshot = {"customer_id": str(wp.customer_id), "plan_content": wp.plan_content, "plan_date": str(wp.plan_date), "status": wp.status}
    update_data = data.model_dump(exclude_unset=True)
    if current_user["role"] not in ("director", "leader"):
        update_data.pop("manager_id", None)
    if "plan_date" in update_data and update_data["plan_date"]:
        update_data["plan_date"] = parse_date(update_data["plan_date"])
    for k, v in update_data.items():
        setattr(wp, k, v)
    new_snapshot = {"customer_id": str(wp.customer_id), "plan_content": wp.plan_content, "plan_date": str(wp.plan_date), "status": wp.status}
    changes = compute_diff(old_snapshot, new_snapshot)
    if changes:
        append_entry(wp, current_user["name"], changes, getattr(data, "edit_reason", None))
    await db.commit()
    await db.refresh(wp)
    return await _enrich(wp, db)


@router.delete("/{plan_id}")
async def delete_work_plan(
    plan_id: str,
    current_user: dict = Depends(require_any_role),
    db: AsyncSession = Depends(get_db),
):
    result = await db.execute(select(WorkPlan).where(WorkPlan.id == plan_id))
    wp = result.scalar_one_or_none()
    if not wp:
        raise HTTPException(status_code=404, detail="Not found")
    if current_user["role"] == "manager" and str(wp.manager_id) != current_user["user_id"]:
        raise HTTPException(status_code=403, detail="Access denied")
    await db.delete(wp)
    await db.commit()
    return {"detail": "deleted"}