feat: add invoice creation logic with SQLAlchemy

api/invoices.py

@@ -0,0 +1,55 @@
+from fastapi import APIRouter, Depends, HTTPException
+from sqlalchemy.orm import Session
+from core.database import get_db
+from models.invoice import Invoice, InvoiceItem
+from pydantic import BaseModel
+from typing import List
+
+router = APIRouter(prefix="/invoices", tags=["Invoices"])
+
+# Pydantic Schemas for validation
+class ItemCreate(BaseModel):
+    description: str
+    quantity: int
+    price_per_unit: float
+
+class InvoiceCreate(BaseModel):
+    invoice_no: str
+    doctor_name: str
+    clinic_name: str
+    patient_name: str
+    shade: str
+    received_amount: float
+    items: List[ItemCreate]
+
+@router.post("/")
+def create_invoice(data: InvoiceCreate, db: Session = Depends(get_db)):
+    # Calculate totals
+    total = sum(item.quantity * item.price_per_unit for item in data.items)
+    
+    new_invoice = Invoice(
+        invoice_no=data.invoice_no,
+        doctor_name=data.doctor_name,
+        clinic_name=data.clinic_name,
+        patient_name=data.patient_name,
+        shade=data.shade,
+        total_amount=total,
+        received_amount=data.received_amount,
+        remaining_balance=total - data.received_amount
+    )
+    
+    db.add(new_invoice)
+    db.flush() # Gets the ID without committing yet
+
+    for item in data.items:
+        db_item = InvoiceItem(
+            invoice_id=new_invoice.id,
+            description=item.description,
+            quantity=item.quantity,
+            price_per_unit=item.price_per_unit,
+            total_price=item.quantity * item.price_per_unit
+        )
+        db.add(db_item)
+    
+    db.commit()
+    return {"status": "success", "invoice_id": new_invoice.id}

core/database.py

@@ -0,0 +1,21 @@
+import os
+from sqlalchemy import create_engine
+from sqlalchemy.ext.declarative import declarative_base
+from sqlalchemy.orm import sessionmaker
+from dotenv import load_dotenv
+
+load_dotenv()
+
+DATABASE_URL = os.getenv("DATABASE_URL")
+
+engine = create_engine(DATABASE_URL)
+SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
+Base = declarative_base()
+
+# Dependency to get DB session
+def get_db():
+    db = SessionLocal()
+    try:
+        yield db
+    finally:
+        db.close()

main.py

@@ -1,29 +1,23 @@
-import os
 from fastapi import FastAPI
-from sqlalchemy import create_engine
-from sqlalchemy.orm import sessionmaker
-from dotenv import load_dotenv
-from fastapi.responses import RedirectResponse
+from fastapi.middleware.cors import CORSMiddleware
+from core.database import engine, Base
+from api.invoices import router as invoice_router
 
-# This will pick up the secret you saved in Hugging Face
-load_dotenv()
+# Create tables in Neon
+Base.metadata.create_all(bind=engine)
 
-DATABASE_URL = os.getenv("DATABASE_URL")
+app = FastAPI(title="SmiloCAD Invoice API")
 
-# Create the SQLAlchemy engine using the modern psycopg driver
-engine = create_engine(DATABASE_URL)
-SessionLocal = sessionmaker(autocommit=False, autoflush=False, bind=engine)
+app.add_middleware(
+    CORSMiddleware,
+    allow_origins=["*"],
+    allow_methods=["*"],
+    allow_headers=["*"],
+)
 
-app = FastAPI()
+# Include the routes from the api folder
+app.include_router(invoice_router)
 
-@app.get("/", include_in_schema=False)
-def root():
-    # This automatically moves the user from / to /docs
-    return RedirectResponse(url="/docs")
-
-@app.get("/health")
-def health_check():
-    # This checks if the URL was loaded correctly from the secrets
-    if DATABASE_URL:
-        return {"status": "Database URL is loaded"}
-    return {"status": "Error: DATABASE_URL not found"}
+@app.get("/")
+def home():
+    return {"message": "Welcome to SmiloCAD API"}

models/invoice.py

@@ -0,0 +1,29 @@
+from sqlalchemy import Column, Integer, String, Float, DateTime, ForeignKey
+from sqlalchemy.orm import relationship
+from datetime import datetime
+from core.database import Base # We will create this next
+
+class Invoice(Base):
+    __tablename__ = "invoices"
+    id = Column(Integer, primary_key=True, index=True)
+    invoice_no = Column(String, unique=True, index=True)
+    doctor_name = Column(String)
+    clinic_name = Column(String)
+    patient_name = Column(String)
+    shade = Column(String)
+    total_amount = Column(Float)
+    received_amount = Column(Float)
+    remaining_balance = Column(Float)
+    
+    items = relationship("InvoiceItem", back_populates="invoice", cascade="all, delete-orphan")
+
+class InvoiceItem(Base):
+    __tablename__ = "invoice_items"
+    id = Column(Integer, primary_key=True, index=True)
+    invoice_id = Column(Integer, ForeignKey("invoices.id"))
+    description = Column(String)
+    quantity = Column(Integer)
+    price_per_unit = Column(Float)
+    total_price = Column(Float)
+
+    invoice = relationship("Invoice", back_populates="items")