from datetime import datetime
from pathlib import Path
from typing import List
from weasyprint import HTML
from app.core.config import settings
from app.core.logging import app_logger
from app.models.invoice import Invoice, InvoiceItem
from app.models.client import Client
from app.models.user import User
def generate_invoice_pdf(
invoice: Invoice,
items: List[InvoiceItem],
client: Client,
user: User,
) -> Path:
"""
Generate a PDF for an invoice and save it to the storage directory
"""
try:
# Create a unique filename
timestamp = datetime.now().strftime("%Y%m%d_%H%M%S")
filename = f"invoice_{invoice.id}_{timestamp}.pdf"
file_path = settings.INVOICE_STORAGE_DIR / filename
# Make sure the directory exists
settings.INVOICE_STORAGE_DIR.mkdir(parents=True, exist_ok=True)
# Generate HTML content for the invoice
html_content = _generate_invoice_html(invoice, items, client, user)
# Convert HTML to PDF
HTML(string=html_content).write_pdf(file_path)
app_logger.info(f"Generated PDF invoice: {file_path}")
return file_path
except Exception as e:
app_logger.error(f"Error generating PDF invoice: {str(e)}")
raise
def _generate_invoice_html(
invoice: Invoice,
items: List[InvoiceItem],
client: Client,
user: User,
) -> str:
"""
Generate HTML content for an invoice
"""
# Calculate totals
subtotal = sum(item.unit_price * item.quantity for item in items)
total = subtotal # Add tax calculations if needed
# Format dates
issued_date = invoice.issued_date.strftime("%Y-%m-%d") if invoice.issued_date else ""
due_date = invoice.due_date.strftime("%Y-%m-%d") if invoice.due_date else ""
# Basic HTML template for the invoice
return f"""
Invoice #{invoice.invoice_number}
From:
{user.full_name}
{user.email}
To:
{client.name}
{client.company_name or ""}
{client.email}
{client.address or ""}
| Description |
Quantity |
Unit Price |
Amount |
{"".join(f"| {item.description} | {item.quantity} | ${item.unit_price:.2f} | ${item.quantity * item.unit_price:.2f} |
" for item in items)}
Subtotal: ${subtotal:.2f}
Total: ${total:.2f}
Thank you for your business!
"""