from fastapi import FastAPI, HTTPException
from fastapi.middleware.cors import CORSMiddleware
from pydantic import BaseModel
from typing import List, Optional

app = FastAPI(title="FastAPI Server", version="1.0.0")

# CORS middleware to allow client requests
app.add_middleware(
    CORSMiddleware,
    allow_origins=["http://localhost:3000", "http://client:3000"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

class Item(BaseModel):
    id: int
    name: str
    description: Optional[str] = None
    price: float

# In-memory database
items_db = [
    Item(id=1, name="Laptop", description="High-performance laptop", price=999.99),
    Item(id=2, name="Mouse", description="Wireless mouse", price=29.99),
    Item(id=3, name="Keyboard", description="Mechanical keyboard", price=79.99),
]

@app.get("/")
async def root():
    return {"message": "FastAPI Server is running!"}

@app.get("/items", response_model=List[Item])
async def get_items():
    return items_db

@app.get("/items/{item_id}", response_model=Item)
async def get_item(item_id: int):
    item = next((item for item in items_db if item.id == item_id), None)
    if item is None:
        raise HTTPException(status_code=404, detail="Item not found")
    return item

@app.post("/items", response_model=Item)
async def create_item(item: Item):
    if any(existing_item.id == item.id for existing_item in items_db):
        raise HTTPException(status_code=400, detail="Item ID already exists")
    items_db.append(item)
    return item

@app.put("/items/{item_id}", response_model=Item)
async def update_item(item_id: int, item: Item):
    if item.id != item_id:
        raise HTTPException(status_code=400, detail="Item ID mismatch")
    
    for idx, existing_item in enumerate(items_db):
        if existing_item.id == item_id:
            items_db[idx] = item
            return item
    
    raise HTTPException(status_code=404, detail="Item not found")

@app.delete("/items/{item_id}")
async def delete_item(item_id: int):
    for idx, item in enumerate(items_db):
        if item.id == item_id:
            deleted_item = items_db.pop(idx)
            return {"message": f"Item {deleted_item.name} deleted successfully"}
    
    raise HTTPException(status_code=404, detail="Item not found")

if __name__ == "__main__":
    import uvicorn
    uvicorn.run(app, host="0.0.0.0", port=8000)