package account

import (
	"context"
	"database/sql"
	"fmt"
	"time"

	"github.com/google/uuid"

	"scrabble/backend/internal/postgres/jet/backend/table"
)

// Reasons recorded on a retained_identities row: what detached the credential from its
// account. The row is written just before the live identities row is removed, preserving
// the legal dossier (which email/vk/tg was linked, and when) even as the identity frees
// for reuse. See docs/ARCHITECTURE.md §9.1.
const (
	retainUnlink = "unlink"
	retainChange = "change"
	retainDelete = "delete"
)

// retainIdentityTx appends a retention-journal row for one identity being detached, inside
// tx. linkedAt is the identity's original creation time; detached_at defaults to now(). It
// must run in the same transaction as the identity removal, so the dossier and the live
// state can never diverge.
func retainIdentityTx(ctx context.Context, tx *sql.Tx, accountID uuid.UUID, kind, externalID string, confirmed bool, linkedAt time.Time, reason string) error {
	id, err := uuid.NewV7()
	if err != nil {
		return fmt.Errorf("account: new retained id: %w", err)
	}
	ins := table.RetainedIdentities.INSERT(
		table.RetainedIdentities.RetainedID, table.RetainedIdentities.AccountID,
		table.RetainedIdentities.Kind, table.RetainedIdentities.ExternalID,
		table.RetainedIdentities.Confirmed, table.RetainedIdentities.LinkedAt,
		table.RetainedIdentities.Reason,
	).VALUES(id, accountID, kind, externalID, confirmed, linkedAt, reason)
	if _, err := ins.ExecContext(ctx, tx); err != nil {
		return fmt.Errorf("account: retain identity (%s, %s): %w", kind, externalID, err)
	}
	return nil
}