import httpx
from fastapi import FastAPI, HTTPException
from pydantic import BaseModel

from circuit_breaker import CircuitBreaker

app = FastAPI()

USER_SERVICE_URL = "http://user-service:8000"
CATALOG_SERVICE_URL = "http://catalog-service:8000"

orders_db = {}
next_id = 1

catalog_cb = CircuitBreaker(failure_threshold=3, recovery_timeout=10)

class CreateOrderDTO(BaseModel):
    user_id: int
    product_id: int
    quantity: int

TIMEOUT = 5.0

def get_product(product_id: int):
    return catalog_cb.call(
        httpx.get,
        f"{CATALOG_SERVICE_URL}/products/{product_id}",
        timeout=TIMEOUT
        )

@app.post("/orders", status_code=201)
async def create_order(payload: CreateOrderDTO):
    global next_id

    user_response = httpx.get(f"{USER_SERVICE_URL}/users/{payload.user_id}")
    try:
        user_response = httpx.get(f"{USER_SERVICE_URL}/users/{payload.user_id}", timeout=TIMEOUT)
    except httpx.TimeoutException:
        raise HTTPException(status_code=503, detail="User service unavailable")
    if user_response.status_code == 404:
        raise HTTPException(status_code=404, detail="User not found")
    
    user = user_response.json()

    try:
        product_response = get_product(payload.product_id)
    except httpx.TimeoutException:
        raise HTTPException(status_code=503, detail="Catalog service unavailable")
    if product_response.status_code == 404:
        raise HTTPException(status_code=404, detail="Product not found")
    
    product = product_response.json()

    try:
        update_response = httpx.put(f"{CATALOG_SERVICE_URL}/products/{payload.product_id}/stock", json= {"quantity": payload.quantity}, timeout=TIMEOUT)
    except httpx.TimeoutException:
        raise HTTPException(status_code=503, detail="Catalog service unavailable")
    if update_response.status_code == 400:
        raise HTTPException(status_code= 400, detail= "Stock Insuffisant")
    if update_response.status_code != 200:
        raise HTTPException(status_code= 502, detail= "Erreur catalog-service")
    
    order_id = next_id
    next_id += 1

    new_order = {
        "id": order_id,
        "user_id": user["id"],
        "user_name": user["name"],
        "product_id": product["id"],
        "product_name": product["name"],
        "unit_price": product["price"],
        "quantity": payload.quantity,
        "total_price": product["price"] * payload.quantity
    }

    orders_db[order_id] = new_order
    return new_order

@app.get("/orders/{order_id}")
async def get_order(order_id: int):
    order = orders_db.get(order_id)
    if not order:
        raise HTTPException(status_code=404, detail="Order not found")
    return order

@app.get("/health")
def health():
    return {"status": "ok", "service": "order-service"}