package verification

import (
	"context"
	"strings"
	"time"

	"git.sendico.io/tech/sxchnge/bff/pkg/merrors"
)

func (db *verificationDB) reserveIssuance(ctx context.Context, request *Request, now time.Time) error {
	if len(request.IssuanceLimits) == 0 {
		return nil
	}
	if db.limits == nil {
		return merrors.ServiceUnavailable("verification rate-limit storage is unavailable")
	}
	for _, limit := range request.IssuanceLimits {
		scopeKind := strings.TrimSpace(limit.ScopeKind)
		if scopeKind == "" || strings.TrimSpace(limit.ScopeHash) == "" || limit.Limit < 1 ||
			limit.WindowStart.IsZero() || !limit.ExpiresAt.After(limit.WindowStart) {
			return merrors.InvalidArgument("invalid verification issuance limit", "issuanceLimits")
		}
		count, err := db.limits.Increment(
			ctx,
			scopeKind,
			limit.ScopeHash,
			limit.WindowStart,
			limit.ExpiresAt,
		)
		if err != nil {
			return merrors.OpaqueWrap(
				merrors.ErrServiceUnavailable,
				err,
				"failed to reserve verification issuance capacity",
			)
		}
		if count > limit.Limit {
			retryAfter := limit.ExpiresAt.Sub(now)
			if retryAfter < time.Second {
				retryAfter = time.Second
			}
			return ErrorIssuanceRateLimited(scopeKind, retryAfter)
		}
	}
	return nil
}