Payment Generator

Purpose & User Intent: The tool generates structured bank transfer instructions and payment references to support invoicing workflows. Primary users are accountants, finance teams, freelancers, and small businesses that issue invoices and need consistent, auditable payment data. It is used when preparing payments or sharing payer/beneficiary details with clients, vendors, or payroll systems. Core Logic & Features: It normalizes inputs, validates IBAN/BBAN formats and currency codes, applies country-specific rules, and constructs a canonical payment instruction block. Required features include input normalization, IBAN validation, and deterministic reference generation based on invoice_id, due_date, and amount. Optional/advanced features include multi-currency presets, API-ready JSON output, and ERP-friendly export formats. Inputs & Outputs: Inputs include payer_name, payer_iban, payer_country, beneficiary_name, beneficiary_iban, amount, currency, due_date, invoice_id, and optional reference. Outputs include a human-readable payment text block and a machine-readable JSON/CSV payload or full transfer record. Validation covers presence of required fields, correct formats, and supported currencies. Algorithms & Calculations: Reference generation uses a deterministic hash of invoice_id, due_date, amount, and involved IBANs; the first 12 alphanumeric characters form the payment reference. IBAN validity uses the standard checksum algorithm; outputs follow ISO standards. Error & Edge Cases: Missing required inputs or invalid IBANs trigger domain errors; unsupported currencies or country codes raise validation warnings; external data unavailability (e.g., IBAN registry) triggers safe fallback. Industry/Region & Localization: Aligns with IBAN/ISO 4217 standards, SWIFT/BIC considerations, and regional date and currency formats; supports localization of currency formatting. Assumptions & Exclusions: Assumes inputs are provided by the user or trusted feeds; does not execute payments, verify bank permissions, or provide UI components; excludes UI styling and front-end behavior.