from fastapi import APIRouter, Depends, Query, UploadFile, File, HTTPException
from fastapi.responses import FileResponse
from typing import Optional
import os
import shutil

from auth.models import TokenPayload
from auth.dependencies import require_permission
from crm.models import ProductCreate, ProductUpdate, ProductInDB, ProductListResponse
from crm import service

router = APIRouter(prefix="/api/crm/products", tags=["crm-products"])

PHOTO_DIR = os.path.join(os.path.dirname(__file__), "..", "storage", "product_images")
os.makedirs(PHOTO_DIR, exist_ok=True)


@router.get("", response_model=ProductListResponse)
def list_products(
    search: Optional[str] = Query(None),
    category: Optional[str] = Query(None),
    active_only: bool = Query(False),
    _user: TokenPayload = Depends(require_permission("crm", "view")),
):
    products = service.list_products(search=search, category=category, active_only=active_only)
    return ProductListResponse(products=products, total=len(products))


@router.get("/{product_id}", response_model=ProductInDB)
def get_product(
    product_id: str,
    _user: TokenPayload = Depends(require_permission("crm", "view")),
):
    return service.get_product(product_id)


@router.post("", response_model=ProductInDB, status_code=201)
def create_product(
    body: ProductCreate,
    _user: TokenPayload = Depends(require_permission("crm", "edit")),
):
    return service.create_product(body)


@router.put("/{product_id}", response_model=ProductInDB)
def update_product(
    product_id: str,
    body: ProductUpdate,
    _user: TokenPayload = Depends(require_permission("crm", "edit")),
):
    return service.update_product(product_id, body)


@router.delete("/{product_id}", status_code=204)
def delete_product(
    product_id: str,
    _user: TokenPayload = Depends(require_permission("crm", "edit")),
):
    service.delete_product(product_id)


@router.post("/{product_id}/photo", response_model=ProductInDB)
async def upload_product_photo(
    product_id: str,
    file: UploadFile = File(...),
    _user: TokenPayload = Depends(require_permission("crm", "edit")),
):
    """Upload a product photo. Accepts JPG or PNG, stored on disk."""
    if file.content_type not in ("image/jpeg", "image/png", "image/webp"):
        raise HTTPException(status_code=400, detail="Only JPG, PNG, or WebP images are accepted.")
    ext = {"image/jpeg": "jpg", "image/png": "png", "image/webp": "webp"}.get(file.content_type, "jpg")
    photo_path = os.path.join(PHOTO_DIR, f"{product_id}.{ext}")
    # Remove any old photo files for this product
    for old_ext in ("jpg", "png", "webp"):
        old_path = os.path.join(PHOTO_DIR, f"{product_id}.{old_ext}")
        if os.path.exists(old_path) and old_path != photo_path:
            os.remove(old_path)
    with open(photo_path, "wb") as f:
        shutil.copyfileobj(file.file, f)
    photo_url = f"/crm/products/{product_id}/photo"
    return service.update_product(product_id, ProductUpdate(photo_url=photo_url))


@router.get("/{product_id}/photo")
def get_product_photo(
    product_id: str,
):
    """Serve a product photo from disk."""
    for ext in ("jpg", "png", "webp"):
        photo_path = os.path.join(PHOTO_DIR, f"{product_id}.{ext}")
        if os.path.exists(photo_path):
            return FileResponse(photo_path)
    raise HTTPException(status_code=404, detail="No photo found for this product.")