Skill Cobranca Automatizada Saas Abacatepay

skill-cobranca-automatizada-saas-abacatepay

When To Use

This skill covers the complete automated billing system ("cobranca automatizada") for Brazilian SaaS products using AbacatePay. Use when implementing or maintaining:

=== Provisioning ===

• Billing configuration tables (cobrancas, cobranca_reguas, billing_config, etc.)
• Dunning rule sequencing (cobranca_regua_eventos)
• Encrypted integration configs (Resend, Evolution API, AbacatePay)

=== Billing Engine ===

• Automated invoice generation and dunning execution via cron
• AbacatePay billing creation (PIX + CARD)
• Webhook processing with HMAC-SHA256 verification
• Invoice state machine (pending, paid, overdue, cancelled, refunded)
• Subscription/plan integration via cobranca_tracking

=== Trial Management ===

• Configurable trial duration
• Pre-expiration notifications (7/3/1 days before)
• Automatic trial expiration and account blocking

=== Interfaces ===

• Public invoice page (FaturaPage) with PIX QR Code, payment link, polling
• Pricing/Plans page with AbacatePay checkout
• User-side invoice listing (MinhasCobrancasSection)
• Admin billing management (cobranças CRUD, planos CRUD, global settings)
• Plan Manager (PlanManager) for user plan changes

=== Notifications ===

• Email via Resend with HTML templates (logo, badge, invoice details)
• WhatsApp via Evolution API with template variables
• Variables: {{nome}}, {{plano}}, {{valor}}, {{vencimento}}, {{link_pagamento}}, {{empresa_nome}}
• Dunning sequence: configurable events with days_apos_vencimento, channel (email/whatsapp/ambos)

Architecture

                     +-------------------+
                     |   Cron (8/12/16h  |
                     |   BRT + 5min)     |
                     +--------+----------+
                              |
         +--------------------+--------------------+
         |                    |                    |
   Processar            Trial               Metrics
   Cobranças          Notificações          (meia-noite)
         |                    |
   +-----v------+      +-----v------+
   | Ver regua   |      | Trial exp. |
   | Send notif  |      | Notif pre  |
   | Create bill |      +------------+
   +-----+------+
         |
   +-----v------------------------------------------+
   |           Controller Layer                      |
   |  cobrancas.ts | abacatepay-webhook.ts           |
   |  fatura.ts    | trial.ts                        |
   +-----+----------------------------+--------------+
         |                            |
   +-----v----------+        +--------v---------+
   |  AbacatePay    |        |  Notifications    |
   |  API v2        |        |  Resend + Evol.  |
   +----------------+        +------------------+
         |
   +-----v----------+
   |  Supabase/     |
   |  PostgreSQL    |
   +----------------+

Billing State Machine

pending ──► paid ──► refunded
  │
  ├──► overdue ──► paid
  │             └──► cancelled
  │
  └──► cancelled

States managed by invoice-state-machine.ts:

• pending: cobrança criada, aguardando pagamento
• paid: paga, released_at setado, conteúdo liberado
• overdue: vencida, entra na régua de cobrança
• cancelled: cancelada manualmente ou por expiração
• refunded: estornada (transição exclusiva de paid)

Key Tables

Full details in billing-tables.md.

Core Flows

Dunning Flow (Régua de Cobrança)

1. Cron runs billing-cron.ts at 8h/12h/16h BRT
2. Queries cobrancas WHERE status = 'overdue' AND NOT paga
3. For each cobranca, resolves billing_config + cobranca_regua + cobranca_regua_eventos
4. Checks if next evento should fire (based on dias_apos_vencimento)
5. Sends notification via billing-sender.ts (email + WhatsApp)
6. If all eventos fired and still overdue, marks as cancelled

Webhook Flow

1. POST /api/abacatepay-webhook receives an AbacatePay v2 event
2. HMAC-SHA256 signature verification (replay + timing-safe compare)
3. Rate limited: 100 req/min per IP
4. On checkout.completed or subscription.renewed: processPaymentWithTransaction updates cobranca + cobranca_tracking
5. On failure: processRollback reverts state
6. Raw event stored in abacatepay_events

Trial Flow

1. trial-cron.ts runs every 5 minutes
2. Queries users where trial ends within notification window
3. Sends pre-expiration notifications (7/3/1 day before)
4. On expiration: blocks account (status = blocked)
5. billing-cron.ts also handles trial notifications at 8/12/16h

Invoice Portal Flow

1. FaturaPage loads by shortlink (8 chars, unique)
2. Materializes billing from AbacatePay API on demand
3. Shows: PIX QR Code, payment link, due date, amount, status badge
4. Polls status every 5 seconds
5. "Share via WhatsApp" button with pre-formatted message

Configuration

billing_config stores encrypted credentials per owner (AES-256-GCM):

• resend_config: Resend API key + from email
• evolution_config: Evolution API URL + API key + instance
• abacatepay_config: AbacatePay API key
• trial_duration_days: Trial length (default)
• Encryption key: BILLING_CONFIG_ENCRYPTION_KEY env var

See billing-config.md for full schema and setup.

Provider API Boundary

• AbacatePay: new code uses API v2 and the webhook events checkout.completed, checkout.refunded, checkout.disputed, subscription.completed, subscription.renewed, and subscription.cancelled. The legacy v1 billing.* events belong behind a migration adapter.
• Resend: keep the key server-side and send through the official SDK or POST https://api.resend.com/emails with Authorization: Bearer <key> and a User-Agent; use Idempotency-Key for retryable sends, record provider request IDs, and redact message content from logs.
• Evolution API: use the deployed v2 documentation and apikey header; keep instance credentials server-side and account for v2.4.0 activation/licensing before diagnosing business-endpoint failures.

Guardrails

1. Keep ALL payment provider secrets server-side. Never expose AbacatePay API keys in browser bundles.
2. Process webhooks idempotently: check cobranca current state before mutating.
3. Treat checkout redirect as advisory. Grant access only after webhook confirmation.
4. Do not log API keys, webhook secrets, full CPF/CNPJ, full phone numbers.
5. Cron must not overlap. billing-cron uses lock checks to prevent concurrent runs.
6. Dunning notifications must respect channel preference (email, whatsapp, or ambos).
7. Trial expiration is irreversible: set status = blocked, do not auto-unblock without payment.
8. Metrics queries (MRR, faturamento) should use aggregateBillingMetrics(), not ad-hoc SQL.
9. New integrations must use https://api.abacatepay.com/v2, /checkouts/create, /subscriptions/create, and /transparents/create as appropriate. Keep /v1/billing/* and billing.* only inside an explicit legacy adapter.

Local Reference (example-saas)

This skill is extracted from the example-saas SaaS billing system. The production codebase is at:

• {{USER_HOME}}/Documents/Code/example-saas/server/controllers/cobrancas.ts — billing CRUD + processing + dunning
• {{USER_HOME}}/Documents/Code/example-saas/server/controllers/abacatepay-webhook.ts — webhook handler
• {{USER_HOME}}/Documents/Code/example-saas/server/controllers/fatura.ts — invoice lookup by shortlink
• {{USER_HOME}}/Documents/Code/example-saas/server/controllers/trial.ts — trial expiration processing
• {{USER_HOME}}/Documents/Code/example-saas/server/services/abacatepay-create-billing-v2.ts — AbacatePay billing creation
• {{USER_HOME}}/Documents/Code/example-saas/server/services/billing-sender.ts — notification dispatch (email + WhatsApp)
• {{USER_HOME}}/Documents/Code/example-saas/server/services/billing-email-template.ts — HTML invoice email template
• {{USER_HOME}}/Documents/Code/example-saas/server/services/billing-integrations-config.ts — encrypted config management
• {{USER_HOME}}/Documents/Code/example-saas/server/services/billing-metrics.ts — MRR and billing metrics
• {{USER_HOME}}/Documents/Code/example-saas/server/utils/invoice-state-machine.ts — state machine logic
• {{USER_HOME}}/Documents/Code/example-saas/server/cron/billing-cron.ts — main billing scheduler
• {{USER_HOME}}/Documents/Code/example-saas/server/cron/trial-cron.ts — trial scheduler
• {{USER_HOME}}/Documents/Code/example-saas/src/pages/FaturaPage.tsx — public invoice page
• {{USER_HOME}}/Documents/Code/example-saas/src/components/PlansPage.tsx — pricing/plans page
• {{USER_HOME}}/Documents/Code/example-saas/src/components/PlanManager.tsx — user plan manager
• {{USER_HOME}}/Documents/Code/example-saas/src/components/AdminCobrancas.tsx — admin billing CRUD
• {{USER_HOME}}/Documents/Code/example-saas/src/components/AdminPlanos.tsx — admin plan CRUD
• {{USER_HOME}}/Documents/Code/example-saas/src/components/AdminGlobalSettings.tsx — global settings
• {{USER_HOME}}/Documents/Code/example-saas/src/components/MinhasCobrancasSection.tsx — user invoice list
• {{USER_HOME}}/Documents/Code/example-saas/supabase/migrations/20260617_cobrancas_foundation.sql — core tables
• {{USER_HOME}}/Documents/Code/example-saas/supabase/migrations/20260617_cobrancas_website_final.sql — shortlink trigger
• {{USER_HOME}}/Documents/Code/example-saas/supabase/migrations/20240101_billing_config.sql — billing_config table
• {{USER_HOME}}/Documents/Code/example-saas/supabase/migrations/20240117_partner_billing.sql — partner billing

Reference Files

• billing-tables.md — complete table schemas, indexes, enums, RLS policies
• billing-flows.md — detailed flow diagrams and pseudocode for each core flow
• billing-config.md — encryption, config resolution, and setup steps
• billing-admin.md — admin interfaces and CRUD operations
• billing-notifications.md — email/WhatsApp templates, dunning sequence, template variables

Validation

• After changes, run build and typecheck (npm run build, npm run typecheck or equivalent)
• Simulate webhook: POST checkout.completed and subscription.renewed events and verify idempotent processing
• Test dunning: create overdue cobranca with regua de 0/3/7 dias and confirm notification dispatch
• Test trial: set trial_duration_days=1, create user, wait for pre-expiration and expiration
• Verify no AbacatePay/Resend/Evolution keys leak to browser bundles
• Run project lint when available

Related Skills

• skill-abacatepay-integration — AbacatePay v2 API specifics and legacy v1 migration boundary
• skill-saas-core-limits — plan limits, entitlements, feature flags after payment
• skill-evolution-api — WhatsApp notification channel
• skill-supabase-rls — RLS policies for billing tables
• skill-saas-factory — top-level SaaS construction entry