from typing import List

from fastapi import APIRouter, Depends, HTTPException, status
from sqlalchemy.orm import Session

from backend.app.db import get_db
from backend.app import models
from backend.app.schemas import (
    CustomerCreate,
    CustomerRead,
    CustomerUpdate,
)


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


@router.get("/", response_model=List[CustomerRead])
async def list_customers(
    q: str | None = None,
    db: Session = Depends(get_db),
):
    """列表客户，支持 q 按名称、联系方式模糊搜索。"""
    query = db.query(models.Customer).order_by(models.Customer.created_at.desc())
    if q and q.strip():
        term = f"%{q.strip()}%"
        query = query.filter(
            (models.Customer.name.ilike(term)) | (models.Customer.contact_info.ilike(term))
        )
    return query.all()


@router.post("/", response_model=CustomerRead, status_code=status.HTTP_201_CREATED)
async def create_customer(payload: CustomerCreate, db: Session = Depends(get_db)):
    customer = models.Customer(
        name=payload.name,
        contact_info=payload.contact_info,
        tags=payload.tags,
    )
    db.add(customer)
    db.commit()
    db.refresh(customer)
    return customer


@router.get("/{customer_id}", response_model=CustomerRead)
async def get_customer(customer_id: int, db: Session = Depends(get_db)):
    customer = db.query(models.Customer).get(customer_id)
    if not customer:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Customer not found")
    return customer


@router.put("/{customer_id}", response_model=CustomerRead)
async def update_customer(
    customer_id: int, payload: CustomerUpdate, db: Session = Depends(get_db)
):
    customer = db.query(models.Customer).get(customer_id)
    if not customer:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Customer not found")

    if payload.name is not None:
        customer.name = payload.name
    if payload.contact_info is not None:
        customer.contact_info = payload.contact_info
    if payload.tags is not None:
        customer.tags = payload.tags

    db.commit()
    db.refresh(customer)
    return customer


@router.delete("/{customer_id}", status_code=status.HTTP_204_NO_CONTENT)
async def delete_customer(customer_id: int, db: Session = Depends(get_db)):
    customer = db.query(models.Customer).get(customer_id)
    if not customer:
        raise HTTPException(status_code=status.HTTP_404_NOT_FOUND, detail="Customer not found")

    db.delete(customer)
    db.commit()
    return None