package store

import (
	"context"
	"time"

	"github.com/loyaly/behavision-server/internal/api"
	"github.com/loyaly/behavision-server/internal/auth"
)

// IssueEnrolmentCode mints the code a shop PC redeems, for one site of one
// client.
//
// The same row the provisioning command writes, hashed by the same function.
// It exists as an API as well because a code is not a one-off: a PC is
// replaced, reinstalled, or moved between shops, and until now every one of
// those was a support ticket and an SSH session. The provisioning command
// remains the bootstrap - a brand new customer has nobody to sign in as yet.
//
// The site id is checked against the CALLER'S client in the same statement
// that inserts, so a code for another tenant's shop cannot be minted by
// guessing a uuid.
func (s *Store) IssueEnrolmentCode(ctx context.Context, clientID, siteID,
	actorID, label string, ttl time.Duration) (api.EnrolmentCode, error) {

	if ttl <= 0 {
		ttl = 7 * 24 * time.Hour
	}
	code, err := auth.NewEnrolmentCode()
	if err != nil {
		return api.EnrolmentCode{}, err
	}
	out := api.EnrolmentCode{Code: code, Label: label, SiteID: siteID}
	expires := time.Now().Add(ttl).UTC()

	err = s.pool.QueryRow(ctx, `
		INSERT INTO site_enrolment_tokens (client_id, site_id, token_hash,
		                                   label, expires_at, created_by)
		SELECT $1::uuid, si.id, $3, $4, $5, $6::uuid
		  FROM sites si
		 WHERE si.id = $2::uuid AND si.client_id = $1::uuid
		RETURNING expires_at, (SELECT name FROM sites WHERE id = $2::uuid)`,
		clientID, siteID, auth.HashToken(auth.NormalizeCode(code)),
		label, expires, nullableUUID(actorID)).
		Scan(&out.ExpiresAt, &out.SiteName)
	// pgx.ErrNoRows travels up as-is, the way RequestCheck already signals a
	// missing row. It means no such site FOR THIS CLIENT, and the handler turns
	// it into a 404: a tenant has no business learning that another tenant's
	// shop exists.
	if err != nil {
		return api.EnrolmentCode{}, err
	}
	return out, nil
}

func nullableUUID(s string) any {
	if s == "" {
		return nil
	}
	return s
}