Validation rule

Rules\Redeemable validates a coupon-code form field and reports a precise, translatable message for the first failing reason — no need to catch six exceptions:

use RoundlyConsulting\Coupons\Rules\Redeemable;

$request->validate([
    'code' => ['required', 'string', new Redeemable(cartTotal: $cartTotal, redeemer: $request->user())],
]);

• Both arguments are optional: omit cartTotal to skip the currency and minimum-spend checks, omit redeemer to skip the per-redeemer cap.
• Empty, blank or non-string input and unknown codes fail with the not_found message. Codes match case-insensitively, so summer passes for SUMMER.
• The rule never mutates anything — usage is only incremented by a redemption.
• It asks Coupons::check() — the same checks, in the same order, as redemption and isRedeemableBy() — so they never disagree.

Messages

Messages live under the coupons::messages namespace; :code is replaced with the coupon code. The package ships English:

Translating

Publish the strings with the coupons-translations tag to reword them, or add a file for another locale under lang/vendor/coupons. For example, Slovak:

// lang/vendor/coupons/sk/messages.php
return [
    'not_found' => 'Kupón „:code“ neexistuje.',
    'currency_mismatch' => 'Tento kupón nie je možné použiť vo zvolenej mene.',
    'minimum_spend_not_met' => 'Hodnota objednávky nedosahuje minimálnu sumu pre tento kupón.',
    'expired' => 'Tento kupón už nie je platný.',
    'at_max_usage' => 'Tento kupón dosiahol limit použití.',
    'already_redeemed' => 'Tento kupón ste už použili.',
];

The rule follows the application locale, so the same form shows the Slovak message once the locale is sk.