#!/usr/bin/env python3 """ Invoice Generator — Python Freelancer Toolkit Generates professional PDF invoices from client data. Usage: python3 09_invoice_generator.py --config invoice_config.json """ import json import argparse import os from datetime import datetime, timedelta from pathlib import Path # Optional: pip install reportlab (falls back to HTML if not installed) try: from reportlab.lib.pagesizes import A4 from reportlab.lib import colors from reportlab.lib.units import mm from reportlab.platypus import SimpleDocTemplate, Table, TableStyle, Paragraph, Spacer from reportlab.lib.styles import getSampleStyleSheet, ParagraphStyle from reportlab.lib.enums import TA_RIGHT, TA_CENTER PDF_AVAILABLE = True except ImportError: PDF_AVAILABLE = False SAMPLE_CONFIG = { "invoice_number": "INV-2024-001", "issue_date": datetime.now().strftime("%Y-%m-%d"), "due_date": (datetime.now() + timedelta(days=14)).strftime("%Y-%m-%d"), "currency": "EUR", "vat_rate": 0.20, "freelancer": { "name": "Your Name", "email": "you@email.com", "address": "Your Address, City, Country", "phone": "+1 234 567 8900", "bank": "IBAN: XX00 0000 0000 0000 0000 0000", "tax_id": "TAX-12345" }, "client": { "name": "Client Company Name", "contact": "Client Contact Person", "email": "client@company.com", "address": "Client Address, City, Country", "vat_number": "VAT-67890" }, "items": [ { "description": "Web Development - Homepage Redesign", "quantity": 1, "unit": "project", "unit_price": 1500.00 }, { "description": "Consulting Sessions", "quantity": 4, "unit": "hours", "unit_price": 150.00 } ], "notes": "Payment due within 14 days. Late payments subject to 2% monthly interest.", "payment_terms": "Bank transfer only. Reference invoice number in payment." } def calculate_totals(items, vat_rate, currency="EUR"): """Calculate invoice totals.""" subtotal = sum(item["quantity"] * item["unit_price"] for item in items) vat_amount = subtotal * vat_rate total = subtotal + vat_amount return { "subtotal": subtotal, "vat_amount": vat_amount, "total": total, "currency": currency } def format_currency(amount, currency="EUR"): """Format amount as currency string.""" symbols = {"EUR": "€", "USD": "$", "GBP": "£", "CHF": "CHF "} symbol = symbols.get(currency, currency + " ") return f"{symbol}{amount:,.2f}" def generate_html_invoice(config): """Generate a professional HTML invoice.""" items = config["items"] totals = calculate_totals(items, config.get("vat_rate", 0), config.get("currency", "EUR")) currency = config.get("currency", "EUR") items_html = "" for item in items: line_total = item["quantity"] * item["unit_price"] items_html += f""" {item['description']} {item['quantity']} {item.get('unit', '')} {format_currency(item['unit_price'], currency)} {format_currency(line_total, currency)} """ vat_rate_pct = config.get("vat_rate", 0) * 100 freelancer = config["freelancer"] client = config["client"] html = f""" Invoice {config['invoice_number']}
{freelancer['name']}
{freelancer['email']}
{freelancer.get('phone', '')}
INVOICE
#{config['invoice_number']}
From
{freelancer['name']}
{freelancer.get('address', '')}
{freelancer.get('tax_id', '')}
{freelancer.get('bank', '')}
Bill To
{client['name']}
{client.get('contact', '')}
{client.get('address', '')}
{client.get('vat_number', '')}
{config['issue_date']}
{config['due_date']}
{config['invoice_number']}
{items_html}
Description Qty Unit Price Amount
Subtotal {format_currency(totals['subtotal'], currency)}
VAT ({vat_rate_pct:.0f}%) {format_currency(totals['vat_amount'], currency)}
TOTAL DUE {format_currency(totals['total'], currency)}

{config.get('notes', '')}

{config.get('payment_terms', '')}

Thank you for your business! • {freelancer['email']}
""" return html def generate_invoice(config_path=None, output_dir="."): """Main function to generate invoice.""" if config_path and os.path.exists(config_path): with open(config_path) as f: config = json.load(f) else: config = SAMPLE_CONFIG print("No config provided. Using sample data.") # Save sample config for reference with open("invoice_sample_config.json", "w") as f: json.dump(SAMPLE_CONFIG, f, indent=2) print("Sample config saved to: invoice_sample_config.json") # Generate HTML html_content = generate_html_invoice(config) invoice_num = config.get("invoice_number", "invoice").replace("/", "-") html_path = os.path.join(output_dir, f"{invoice_num}.html") with open(html_path, "w") as f: f.write(html_content) print(f"✓ HTML invoice saved: {html_path}") # Summary items = config["items"] totals = calculate_totals(items, config.get("vat_rate", 0), config.get("currency", "EUR")) currency = config.get("currency", "EUR") print(f"\n--- Invoice Summary ---") print(f"Invoice #: {config['invoice_number']}") print(f"Client: {config['client']['name']}") print(f"Due: {config['due_date']}") print(f"Subtotal: {format_currency(totals['subtotal'], currency)}") print(f"VAT: {format_currency(totals['vat_amount'], currency)}") print(f"TOTAL: {format_currency(totals['total'], currency)}") return html_path if __name__ == "__main__": parser = argparse.ArgumentParser(description="Generate professional invoices") parser.add_argument("--config", help="Path to JSON config file") parser.add_argument("--output", default=".", help="Output directory") args = parser.parse_args() generate_invoice(args.config, args.output)