solar-invoice

byManish Salav

Build a production-grade, full-stack Progressive Web App (PWA) for managing small business billing and professional invoicing. The architecture must be scalable, secure, and follow standard commerce accounting rules. 1. Roles & Permissions: Owner: Can manage company profiles, tax settings (GST), all clients, and all invoices. Manager: Can create and edit invoices and clients, but cannot delete records or change company tax settings. 2. Data Objects & Relationships: CompanyProfile: name, GSTIN (string), address, logo_url, bank_details. Client: name, email, phone, address, tax_id. Invoice: invoice_number (auto-increment), date, due_date, status (Draft/Unpaid/Paid), client_id, subtotal, discount, tax_amount (GST), total. LineItem: description, quantity (integer), unit_price (decimal), tax_rate, total_price. 3. Required Screens & Workflows: Dashboard: Summary cards for "Total Revenue," "Pending Payments," and a bar chart showing monthly billing trends. Invoice Generator: A multi-step form to select a Client, add LineItems (with auto-calculating totals), and set tax rates. Client Management: A searchable table of all clients with a "Quick Add" button. PDF Export: A dedicated workflow to generate a professional, print-ready PDF invoice from an Invoice ID. 4. Business Logic & Guardrails: Calculation Engine: Implement logic where ItemTotal = (Qty * Price). Subtotal = sum(ItemTotals). Tax = Subtotal * TaxRate. Validation: An invoice cannot be marked "Paid" without a recorded payment date. Invoice numbers must be unique and non-editable once finalized. 5. Technical Stack Preferences: Frontend: Next.js with Tailwind CSS (Modern Corporate Aesthetic: White bg, Deep Blue accents). Backend: Node.js with a PostgreSQL database. Deployment: Kubernetes-ready with CI/CD scaffolding.