package integration

import (
	"context"
	"encoding/json"
	"fmt"
)

// Enqueue inserts a pending core.outbox row — the transactional dispatch
// handoff ratified in design.md Decision 4 for the integration-extraction
// change: a domain write and its outbox row commit atomically inside the
// caller's Postgres transaction, and a separate poller (e.g. the Stripe
// outbox drainer, internal/integrations/stripe/workflows's
// PollIntegrationOutbox) executes the action against the external provider
// later.
//
// This is the only supported write path into core.outbox; core code must
// not INSERT into it directly (see Decision 4's "concession to
// coherence"). It replaces the raw `INSERT INTO core.outbox` statements
// formerly hand-written in internal/server/operator_billing.go and
// internal/integrations/stripe/store/ensure_customer.go.
//
// db accepts a *sql.DB or a *sql.Tx via this package's DBTX interface
// (generated by sqlc for the provider-registry querier but equally
// satisfied by both). Pass a *sql.Tx to keep the enqueue atomic with the
// caller's other writes in the same transaction — the pattern both
// converted call sites rely on. A single logical action (e.g. "create the
// product, then its price") that needs more than one outbox row is two
// separate Enqueue calls against the same *sql.Tx, not a batch API: this
// keeps the helper's shape simple and the atomicity guarantee is already
// provided by the shared transaction.
//
// payload is marshaled to JSON here — pass a struct or map, not
// pre-marshaled bytes. providerKey and actionType are the outbox's
// existing free-form vocabulary (e.g. "stripe" / "create_stripe_customer");
// this helper does not validate or constrain that vocabulary (the Stripe
// action-type vocabulary baked into core is the payments-seam follow-up
// noted in design.md Decision 4, out of scope here).
func Enqueue(ctx context.Context, db DBTX, providerKey, actionType string, payload any) error {
	payloadJSON, err := json.Marshal(payload)
	if err != nil {
		return fmt.Errorf("marshal outbox payload for %s/%s: %w", providerKey, actionType, err)
	}
	if _, err := db.ExecContext(ctx,
		`INSERT INTO core.outbox (provider, action_type, payload) VALUES ($1, $2, $3)`,
		providerKey, actionType, payloadJSON,
	); err != nil {
		return fmt.Errorf("enqueue %s/%s outbox entry: %w", providerKey, actionType, err)
	}
	return nil
}