feat: Enhance traits with strict types and improve method signatures

- Added strict types declaration to multiple traits for better type safety.
- Updated method signatures in traits to use nullable types where applicable.
- Improved documentation for traits, including host-model contracts and method descriptions.
- Added new tests to ensure correct behavior of loan checkout and stock management.
- Fixed regression in order number generation to ensure proper string formatting.
- Ensured that currency codes sent to Stripe are consistently lowercased.

composer.json

@@ -18,7 +18,7 @@
         }
     },
     "require": {
-        "php": "^8.2|^8.3",
+        "php": "^8.2|^8.3|^8.4",
         "illuminate/support": "^9.0|^10.0|^11.0|^12.0|^13.0",
         "illuminate/database": "^9.0|^10.0|^11.0|^12.0|^13.0",
         "blax-software/laravel-workkit": "dev-master|*",

src/Console/Commands/ReleaseExpiredStocks.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Console\Commands;
 
 use Blax\Shop\Models\ProductStock;

src/Console/Commands/ShopAddExampleProducts.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Console\Commands;
 
 use Blax\Shop\Enums\ProductStatus;
@@ -673,7 +675,7 @@ class ShopAddExampleProducts extends Command
             $parking = Product::create([
                 'slug' => $pool->slug . '-' . \Illuminate\Support\Str::slug($itemName),
                 'name' => $itemName,
-                'sku' => $pool->sku . '-' . str_pad($i + 1, 2, '0', STR_PAD_LEFT),
+                'sku' => $pool->sku . '-' . str_pad((string) ($i + 1), 2, '0', STR_PAD_LEFT),
                 'type' => ProductType::BOOKING,
                 'status' => ProductStatus::PUBLISHED,
                 'is_visible' => false,

src/Console/Commands/ShopCleanupCartsCommand.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Console\Commands;
 
 use Blax\Shop\Facades\Shop;

src/Console/Commands/ShopListProductsCommand.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Console\Commands;
 
 use Illuminate\Console\Command;

src/Console/Commands/ShopListPurchasesCommand.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Console\Commands;
 
 use Illuminate\Console\Command;

src/Console/Commands/ShopReinstallCommand.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Console\Commands;
 
 use Illuminate\Console\Command;

src/Console/Commands/ShopSetupStripeWebhooksCommand.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Console\Commands;
 
 use Illuminate\Console\Command;

src/Console/Commands/ShopStatsCommand.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Console\Commands;
 
 use Blax\Shop\Models\ProductAction;

src/Console/Commands/ShopTestActionCommand.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Console\Commands;
 
 use Blax\Shop\Models\ProductAction;

src/Console/Commands/ShopToggleActionCommand.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Console\Commands;
 
 use Blax\Shop\Models\ProductAction;

src/Contracts/Cartable.php

@@ -1,7 +1,30 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Contracts;
 
+/**
+ * Marker contract for anything that can be added to a {@see \Blax\Shop\Models\Cart}.
+ *
+ * The contract is intentionally empty — implementing `Cartable` declares
+ * intent. {@see \Blax\Shop\Models\Cart::addToCart()} checks
+ * `$item instanceof Cartable` and rejects models that haven't opted in,
+ * to prevent accidentally cart-ing rows that have no domain meaning as a
+ * purchase line (a `User` or `Address`, say).
+ *
+ * Implementors typically also implement {@see Purchasable} so the cart
+ * can resolve a price, but the two are independent — a `ProductPrice`
+ * row is `Cartable` only (the {@see Purchasable} half lives on the
+ * parent `Product`).
+ *
+ * Pair this with {@see \Blax\Shop\Traits\IsSimplePurchasable} on a plain
+ * Eloquent model for a no-subclass integration, or extend
+ * {@see \Blax\Shop\Models\Product} for the full e-commerce surface.
+ *
+ * @see \Blax\Shop\Models\Cart::addToCart()
+ * @see \Blax\Shop\Exceptions\CartableInterfaceException Thrown when a non-Cartable model is passed to the cart.
+ */
 interface Cartable
 {
 }

src/Contracts/Chargable.php

@@ -1,10 +1,48 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Contracts;
 
+/**
+ * Contract for billable parties (typically the customer / authenticated user)
+ * that own one or more stored payment methods on a payment provider.
+ *
+ * A `Chargable` actor is the *who* in "who pays for this {@see Purchasable}".
+ * Orders and recurring charges resolve the actor's preferred provider +
+ * method through this contract before handing off to the payment service.
+ *
+ * Reference implementation: pair {@see \Blax\Shop\Traits\HasPaymentMethods}
+ * onto a `User` model — the trait satisfies both contract methods (the
+ * Collection it returns degrades to an array via Eloquent's serialization,
+ * which is what the array return type on this interface captures).
+ *
+ * Note: this contract is deliberately small. Anything beyond "which method
+ * do I bill against" lives on {@see \Blax\Shop\Models\PaymentMethod} or
+ * the provider service ({@see \Blax\Shop\Services\PaymentProvider\PaymentProviderService}).
+ */
 interface Chargable
 {
+    /**
+     * Return the provider key of the actor's default payment method
+     * (e.g. `'stripe'`), or `null` when none is configured yet.
+     *
+     * The order pipeline uses this to pick the right provider service
+     * when no method is supplied explicitly at checkout.
+     */
     public function getDefaultPaymentMethod(): ?string;
 
+    /**
+     * Return the actor's payment methods.
+     *
+     * Implementations may return an indexed array of method
+     * descriptors or any iterable that array-casts cleanly — the
+     * canonical implementation on {@see \Blax\Shop\Traits\HasPaymentMethods}
+     * returns an {@see \Illuminate\Support\Collection} of
+     * {@see \Blax\Shop\Models\PaymentMethod}, which satisfies this
+     * contract via Collection-to-array coercion.
+     *
+     * @return array<int, mixed>|\Illuminate\Support\Collection
+     */
     public function paymentMethods(): array;
 }

src/Contracts/Purchasable.php

@@ -1,19 +1,96 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Contracts;
 
+/**
+ * Contract for models that can be priced, stocked, and recorded as a purchase.
+ *
+ * Where {@see Cartable} is a pure marker, `Purchasable` is the *behavioural*
+ * surface the cart, checkout, and order machinery rely on:
+ *
+ *  - **Pricing** — {@see self::getCurrentPrice()} and
+ *    {@see self::getPriceAttribute()} resolve the unit price the cart
+ *    will charge. Sale-aware implementations toggle on
+ *    {@see self::isOnSale()}.
+ *  - **Inventory** — {@see self::decreaseStock()} runs when a unit is
+ *    consumed (cart checkout, loan checkout); {@see self::increaseStock()}
+ *    when one is returned. Both return `bool` so the caller can detect
+ *    a sold-out condition without an exception.
+ *  - **Audit trail** — {@see self::purchases()} exposes the historic
+ *    record of consumption events as a polymorphic relation against
+ *    {@see \Blax\Shop\Models\ProductPurchase}.
+ *
+ * Two reference implementations ship in the package:
+ *
+ *  - {@see \Blax\Shop\Models\Product} — the full e-commerce model.
+ *  - {@see \Blax\Shop\Traits\IsSimplePurchasable} — drop-in trait for
+ *    host models that want the contract without subclassing `Product`.
+ *
+ * @see \Blax\Shop\Models\ProductPurchase
+ * @see \Blax\Shop\Traits\HasStocks Reference inventory implementation.
+ */
 interface Purchasable
 {
+    /**
+     * Resolve the unit price this item should currently be charged at,
+     * in the package's monetary unit (integer cents floated for math).
+     *
+     * Return `null` when no price is configured; callers (cart, order
+     * total) treat `null` as "free" or as an error depending on context.
+     */
     public function getCurrentPrice(): ?float;
 
+    /**
+     * Eloquent attribute accessor for `$model->price` — the same value
+     * {@see self::getCurrentPrice()} resolves, exposed for convenience
+     * in Blade / JSON serialization.
+     */
     public function getPriceAttribute(): ?float;
 
+    /**
+     * Whether the item is currently selling at a discounted price.
+     *
+     * Pricing logic uses this to pick between {@see self::getCurrentPrice()}
+     * and a sale price source. Implementations that don't support sales
+     * may always return `false`.
+     */
     public function isOnSale(): bool;
 
+    /**
+     * Consume `$quantity` units of inventory.
+     *
+     * Returns `true` when stock was successfully reduced (or when the
+     * implementation doesn't track stock and so always reports success).
+     * Returns `false` to signal "not enough"; implementations may
+     * alternatively throw {@see \Blax\Shop\Exceptions\NotEnoughStockException}.
+     *
+     * Race-safety: implementations should prefer an atomic conditional
+     * UPDATE over a `lockForUpdate` dance — see the laravel-shop
+     * principles doc for the canonical pattern.
+     */
     public function decreaseStock(int $quantity = 1): bool;
 
+    /**
+     * Restore `$quantity` units to inventory (e.g. on a return / refund).
+     *
+     * Symmetric to {@see self::decreaseStock()}. Returning `false` means
+     * the implementation declined to record the change (typically because
+     * stock management is disabled on this record).
+     */
     public function increaseStock(int $quantity = 1): bool;
 
+    /**
+     * Polymorphic relation to the purchase history.
+     *
+     * Implementations return a {@see \Illuminate\Database\Eloquent\Relations\MorphMany}
+     * pointing at {@see \Blax\Shop\Models\ProductPurchase} via the
+     * `purchasable_*` columns. The return type is intentionally
+     * unconstrained on the interface to preserve backward compatibility
+     * — see the canonical implementations on `Product` and `IsSimplePurchasable`.
+     *
+     * @return \Illuminate\Database\Eloquent\Relations\MorphMany<\Blax\Shop\Models\ProductPurchase, $this>
+     */
     public function purchases();
-
 }

src/Enums/BillingScheme.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Enums;
 
 enum BillingScheme: string

src/Enums/CartStatus.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Enums;
 
 enum CartStatus: string

src/Enums/OrderStatus.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Enums;
 
 /**

src/Enums/PriceType.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Enums;
 
 enum PriceType: string

src/Enums/PricingStrategy.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Enums;
 
 enum PricingStrategy: string

src/Enums/ProductAttributeType.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Enums;
 
 enum ProductAttributeType: string

src/Enums/ProductRelationType.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Enums;
 
 enum ProductRelationType: string

src/Enums/ProductStatus.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Enums;
 
 enum ProductStatus: string

src/Enums/ProductType.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Enums;
 
 enum ProductType: string

src/Enums/PurchaseStatus.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Enums;
 
 enum PurchaseStatus: string

src/Enums/RecurringInterval.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Enums;
 
 enum RecurringInterval: string

src/Enums/StockStatus.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Enums;
 
 /**

src/Enums/StockType.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Enums;
 
 /**

src/Events/LoanCreated.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Events;
 
 use Blax\Shop\Models\ProductPurchase;

src/Events/LoanExtended.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Events;
 
 use Blax\Shop\Models\ProductPurchase;

src/Events/LoanReturned.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Events;
 
 use Blax\Shop\Models\ProductPurchase;

src/Events/ProductCreated.php

@@ -1,11 +1,21 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Events;
 
 use Blax\Shop\Models\Product;
 use Illuminate\Foundation\Events\Dispatchable;
 use Illuminate\Queue\SerializesModels;
 
+/**
+ * Dispatched automatically by {@see Product} via the model's
+ * `$dispatchesEvents` map after a new product row is inserted.
+ *
+ * Listeners typically use this for downstream sync (push to Stripe, build a
+ * search index entry, warm a cache). The model is passed already persisted
+ * — listeners can read `$event->product->id`.
+ */
 class ProductCreated
 {
     use Dispatchable, SerializesModels;

src/Events/ProductUpdated.php

@@ -1,11 +1,22 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Events;
 
 use Blax\Shop\Models\Product;
 use Illuminate\Foundation\Events\Dispatchable;
 use Illuminate\Queue\SerializesModels;
 
+/**
+ * Dispatched automatically by {@see Product} via the model's
+ * `$dispatchesEvents` map whenever an existing product row is saved
+ * (after the `updated` model event fires).
+ *
+ * Pairs with {@see ProductCreated} for any sink that needs to react to
+ * the full product write surface — search reindex, cache invalidation,
+ * Stripe price sync, etc.
+ */
 class ProductUpdated
 {
     use Dispatchable, SerializesModels;

src/Exceptions/CartAlreadyConvertedException.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Exceptions;
 
 use Exception;

src/Exceptions/CartDatesRequiredException.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Exceptions;
 
 use Exception;

src/Exceptions/CartEmptyException.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Exceptions;
 
 use Exception;

src/Exceptions/CartItemMissingInformationException.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Exceptions;
 
 use Exception;

src/Exceptions/CartNotReadyException.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Exceptions;
 
 use Exception;

src/Exceptions/CartableInterfaceException.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Exceptions;
 
 use Exception;

src/Exceptions/HasNoDefaultPriceException.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Exceptions;
 
 class HasNoDefaultPriceException extends NotPurchasable

src/Exceptions/HasNoPriceException.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Exceptions;
 
 class HasNoPriceException extends NotPurchasable

src/Exceptions/InvalidBookingConfigurationException.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Exceptions;
 
 class InvalidBookingConfigurationException extends NotPurchasable

src/Exceptions/InvalidDateRangeException.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Exceptions;
 
 use Exception;

src/Exceptions/InvalidPoolConfigurationException.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Exceptions;
 
 class InvalidPoolConfigurationException extends NotPurchasable

src/Exceptions/InvalidPricingStrategyException.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Exceptions;
 
 use Exception;

src/Exceptions/MultiplePurchaseOptions.php

@@ -1,7 +1,28 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Exceptions;
 
 use Exception;
 
-class MultiplePurchaseOptions extends Exception {}
+/**
+ * Thrown when a single purchase path cannot be auto-selected because the
+ * product exposes multiple options (e.g. several variants, several
+ * default prices, several configurations) and the caller did not specify
+ * which one to use.
+ *
+ * Typical resolution at the call site: surface the available options to
+ * the user / API consumer and re-issue the request with an explicit
+ * choice, rather than letting the package guess.
+ */
+class MultiplePurchaseOptions extends Exception
+{
+    public function __construct(
+        string $message = 'Multiple purchase options are available — caller must pick one explicitly.',
+        int $code = 0,
+        ?\Throwable $previous = null
+    ) {
+        parent::__construct($message, $code, $previous);
+    }
+}

src/Exceptions/NotEnoughAvailableInTimespanException.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Exceptions;
 
 use Exception;

src/Exceptions/NotEnoughStockException.php

@@ -1,7 +1,31 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Exceptions;
 
 use Exception;
 
-class NotEnoughStockException extends Exception {}
+/**
+ * Thrown when a stock-consuming operation cannot proceed because the
+ * available quantity is below the requested amount.
+ *
+ * Raised from {@see \Blax\Shop\Traits\HasStocks::decreaseStock()},
+ * {@see \Blax\Shop\Traits\HasStocks::adjustStock()}, and
+ * {@see \Blax\Shop\Models\ProductStock::claim()}.
+ *
+ * The message defaults to a generic phrase so the exception can be raised
+ * with no arguments from helper paths; pass a richer message at the call
+ * site when the calling context can describe the product, requested
+ * quantity, or surrounding operation.
+ */
+class NotEnoughStockException extends Exception
+{
+    public function __construct(
+        string $message = 'Not enough stock available for the requested operation.',
+        int $code = 0,
+        ?\Throwable $previous = null
+    ) {
+        parent::__construct($message, $code, $previous);
+    }
+}

src/Exceptions/NotPoolProductException.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Exceptions;
 
 use Exception;

src/Exceptions/NotPurchasable.php

@@ -1,7 +1,34 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Exceptions;
 
 use Exception;
 
-class NotPurchasable extends Exception {}
+/**
+ * Base exception for any condition that prevents an item from being
+ * legally added to a cart or charged.
+ *
+ * Subclasses describe the specific failure mode while sharing a single
+ * catchable parent — callers that just want to translate any
+ * "not-purchasable" outcome to a 422 response can `catch (NotPurchasable
+ * $e)` without enumerating every concrete case.
+ *
+ * Concrete subclasses shipped by the package:
+ *
+ *  - {@see HasNoPriceException} — no price record exists.
+ *  - {@see HasNoDefaultPriceException} — prices exist but none is marked default.
+ *  - {@see InvalidBookingConfigurationException} — booking product is misconfigured.
+ *  - {@see InvalidPoolConfigurationException} — pool product is misconfigured.
+ */
+class NotPurchasable extends Exception
+{
+    public function __construct(
+        string $message = 'This item cannot be purchased in its current state.',
+        int $code = 0,
+        ?\Throwable $previous = null
+    ) {
+        parent::__construct($message, $code, $previous);
+    }
+}

src/Exceptions/PoolHasNoItemsException.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Exceptions;
 
 use Exception;

src/Exceptions/PriceCalculationException.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Exceptions;
 
 use Exception;

src/Exceptions/ProductHasNoPriceException.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Exceptions;
 
 use Exception;

src/Exceptions/ProductMissingAssociationException.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Exceptions;
 
 use Exception;

src/Exceptions/StripeNotEnabledException.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Exceptions;
 
 use Exception;

src/Exceptions/UnsupportedPaymentProviderException.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Exceptions;
 
 use Exception;

src/Facades/Cart.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Facades;
 
 use Illuminate\Support\Facades\Facade;

src/Facades/Shop.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Facades;
 
 use Illuminate\Support\Facades\Facade;

src/Http/Controllers/Api/CategoryController.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Http\Controllers\Api;
 
 use Blax\Shop\Models\ProductCategory;

src/Http/Controllers/Api/PaymentMethodController.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Http\Controllers\Api;
 
 use Blax\Shop\Models\PaymentMethod;

src/Http/Controllers/Api/ProductController.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Http\Controllers\Api;
 
 use Illuminate\Http\JsonResponse;

src/Http/Controllers/StripeCheckoutController.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Http\Controllers;
 
 use Blax\Shop\Models\Cart;

src/Http/Controllers/StripeWebhookController.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Http\Controllers;
 
 use Blax\Shop\Enums\CartStatus;

src/Http/Resources/LoanResource.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Http\Resources;
 
 /**

src/Http/Resources/PurchaseResource.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Http\Resources;
 
 use Blax\Shop\Models\ProductPurchase;

src/Models/Cart.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Models;
 
 use Blax\Shop\Contracts\Cartable;
@@ -946,7 +948,7 @@ class Cart extends Model
             ->where('customer_type', $userModel);
     }
 
-    public static function scopeUnpaid($query)
+    public function scopeUnpaid($query)
     {
         return $query->whereDoesntHave('purchases', function ($q) {
             $q->whereColumn('total_amount', '!=', 'amount_paid');
@@ -2034,10 +2036,20 @@ class Cart extends Model
             // Price is already stored in cents, Stripe expects smallest currency unit
             $unitAmountCents = (int) $item->price;
 
+            // Stripe wants lowercase ISO-4217 currency codes. Resolve from
+            // the cart item's price relation first (the source of truth for
+            // the line being charged), then the cart's own currency column,
+            // then the package default — never assume the cart row has one.
+            $lineCurrency = strtolower(
+                $item->price()->first()?->currency
+                    ?? $this->currency
+                    ?? config('shop.currency', 'usd')
+            );
+
             // Build line item using price_data for dynamic pricing
             $lineItem = [
                 'price_data' => [
-                    'currency' => $item->price->currency ?? strtoupper($this->currency),
+                    'currency' => $lineCurrency,
                     'product_data' => [
                         'name' => $productName,
                         ...($description ? ['description' => $description] : []),
@@ -2064,7 +2076,7 @@ class Cart extends Model
         // Prepare session parameters
         $sessionParams = [
             'payment_method_types' => ['card'],
-            'currency' => strtoupper($this->currency),
+            'currency' => strtolower($this->currency ?? config('shop.currency', 'usd')),
             'line_items' => $lineItems,
             'mode' => 'payment',
             'success_url' => $success_url,

src/Models/CartItem.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Models;
 
 use Blax\Shop\Exceptions\InvalidDateRangeException;

src/Models/Order.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Models;
 
 use Blax\Shop\Enums\OrderStatus;
@@ -179,7 +181,8 @@ class Order extends Model
         if ($lastOrder) {
             // Extract the sequence number and increment
             $lastNumber = (int) substr($lastOrder->order_number, strlen("{$prefix}{$date}"));
-            $sequence = str_pad($lastNumber + 1, 4, '0', STR_PAD_LEFT);
+            // str_pad requires a string under strict_types — cast the int explicitly.
+            $sequence = str_pad((string) ($lastNumber + 1), 4, '0', STR_PAD_LEFT);
         } else {
             $sequence = '0001';
         }

src/Models/OrderNote.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Models;
 
 use Illuminate\Database\Eloquent\Concerns\HasUuids;

src/Models/PaymentMethod.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Models;
 
 use Blax\Shop\Database\Factories\PaymentMethodFactory;

src/Models/PaymentProviderIdentity.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Models;
 
 use Blax\Shop\Database\Factories\PaymentProviderIdentityFactory;

src/Models/Product.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Models;
 
 use Blax\Shop\Contracts\Cartable;
@@ -24,13 +26,65 @@ use Blax\Shop\Traits\HasPricingStrategy;
 use Blax\Shop\Traits\HasProductRelations;
 use Blax\Shop\Traits\HasStocks;
 use Blax\Shop\Traits\MayBePoolProduct;
+use Illuminate\Database\Eloquent\Builder;
 use Illuminate\Database\Eloquent\Concerns\HasUuids;
 use Illuminate\Database\Eloquent\Factories\HasFactory;
 use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
 use Illuminate\Database\Eloquent\Relations\HasMany;
 use Illuminate\Database\Eloquent\Relations\MorphMany;
 use Illuminate\Support\Facades\Cache;
 
+/**
+ * Core product entity — sellable, stockable, priceable.
+ *
+ * Product is the polymorphic root for the whole package. Specialized
+ * behaviour comes from composed traits:
+ *
+ *  - {@see HasStocks} — inventory and reservations.
+ *  - {@see HasPrices} — price list and default-price resolution.
+ *  - {@see HasPricingStrategy} — average / lowest / highest tier strategy.
+ *  - {@see HasCategories} — category attachment.
+ *  - {@see HasProductRelations} — cross-sells, upsells, pool↔single links.
+ *  - {@see MayBePoolProduct} — pool aggregation when `type = POOL`.
+ *  - {@see ChecksIfBooking} — booking-product helpers when `type = BOOKING`.
+ *
+ * Host apps can extend this model (`Book extends Product` style) for free —
+ * every relation declares its FK explicitly so subclasses don't break.
+ *
+ * @property string $id
+ * @property string $slug
+ * @property string|null $sku
+ * @property \Blax\Shop\Enums\ProductType $type
+ * @property string|null $stripe_product_id
+ * @property \Illuminate\Support\Carbon|null $sale_start
+ * @property \Illuminate\Support\Carbon|null $sale_end
+ * @property bool $manage_stock
+ * @property int|null $low_stock_threshold
+ * @property float|null $weight
+ * @property float|null $length
+ * @property float|null $width
+ * @property float|null $height
+ * @property bool $virtual
+ * @property bool $downloadable
+ * @property string|null $parent_id
+ * @property bool $featured
+ * @property bool $is_visible
+ * @property \Blax\Shop\Enums\ProductStatus $status
+ * @property \Illuminate\Support\Carbon|null $published_at
+ * @property \stdClass $meta
+ * @property string|null $tax_class
+ * @property int $sort_order
+ * @property string $name
+ * @property string|null $description
+ * @property string|null $short_description
+ *
+ * @property-read Product|null $parent
+ * @property-read \Illuminate\Database\Eloquent\Collection<int, Product> $children
+ * @property-read \Illuminate\Database\Eloquent\Collection<int, ProductAttribute> $attributes
+ * @property-read \Illuminate\Database\Eloquent\Collection<int, ProductAction> $actions
+ * @property-read \Illuminate\Database\Eloquent\Collection<int, ProductPurchase> $purchases
+ */
 class Product extends Model implements Purchasable, Cartable
 {
     use HasFactory, HasUuids, HasMetaTranslation, HasStocks, HasPrices, HasPricingStrategy, HasCategories, HasProductRelations, MayBePoolProduct, ChecksIfBooking;
@@ -141,11 +195,23 @@ class Product extends Model implements Purchasable, Cartable
         });
     }
 
-    public function parent()
+    /**
+     * Parent product when this row is a variant / grouped child / pool single
+     * item. Top-level products have `parent_id = null`.
+     *
+     * @return BelongsTo<static, $this>
+     */
+    public function parent(): BelongsTo
     {
         return $this->belongsTo(static::class, 'parent_id');
     }
 
+    /**
+     * Variants, grouped children, or pool single items hanging off this
+     * product. Returns an empty collection for leaf rows.
+     *
+     * @return HasMany<static, $this>
+     */
     public function children(): HasMany
     {
         return $this->hasMany(static::class, 'parent_id');
@@ -156,7 +222,7 @@ class Product extends Model implements Purchasable, Cartable
         // Explicit FK so the relation still targets `product_id` when a host
         // app subclasses Product (e.g. `Book extends Product`).
         return $this->hasMany(
-            config('shop.models.product_attribute', 'Blax\Shop\Models\ProductAttribute'),
+            config('shop.models.product_attribute', ProductAttribute::class),
             'product_id'
         );
     }
@@ -177,12 +243,20 @@ class Product extends Model implements Purchasable, Cartable
         );
     }
 
-    public function scopePublished($query)
+    /**
+     * @param  Builder<static>  $query
+     * @return Builder<static>
+     */
+    public function scopePublished(Builder $query): Builder
     {
         return $query->where('status', ProductStatus::PUBLISHED->value);
     }
 
-    public function scopeFeatured($query)
+    /**
+     * @param  Builder<static>  $query
+     * @return Builder<static>
+     */
+    public function scopeFeatured(Builder $query): Builder
     {
         return $query->where('featured', true);
     }
@@ -364,7 +438,14 @@ class Product extends Model implements Purchasable, Cartable
         return ProductAction::getAvailableActions();
     }
 
-    public function callActions(string $event = 'purchased', ?ProductPurchase $productPurchase = null, array $additionalData = [])
+    /**
+     * Dispatch every {@see ProductAction} configured on this product for
+     * `$event`. Returns whatever {@see ProductAction::callForProduct()}
+     * returns (typically a collection of {@see ProductActionRun} rows).
+     *
+     * @param  array<string, mixed>  $additionalData Free-form payload merged into the action context.
+     */
+    public function callActions(string $event = 'purchased', ?ProductPurchase $productPurchase = null, array $additionalData = []): mixed
     {
         return ProductAction::callForProduct(
             $this,
@@ -374,7 +455,14 @@ class Product extends Model implements Purchasable, Cartable
         );
     }
 
-    public function scopeVisible($query)
+    /**
+     * Visible to customers right now: `is_visible = true`, status PUBLISHED,
+     * and `published_at` either null or in the past.
+     *
+     * @param  Builder<static>  $query
+     * @return Builder<static>
+     */
+    public function scopeVisible(Builder $query): Builder
     {
         return $query->where('is_visible', true)
             ->where('status', ProductStatus::PUBLISHED->value)
@@ -384,7 +472,15 @@ class Product extends Model implements Purchasable, Cartable
             });
     }
 
-    public function scopeSearch($query, string $search)
+    /**
+     * Substring match on slug / SKU / name. Cheap LIKE — not a full-text
+     * index; host apps that need stronger search should add Scout or
+     * MeiliSearch alongside this scope.
+     *
+     * @param  Builder<static>  $query
+     * @return Builder<static>
+     */
+    public function scopeSearch(Builder $query, string $search): Builder
     {
         return $query->where(function ($q) use ($search) {
             $q->where('slug', 'like', "%{$search}%")
@@ -544,8 +640,11 @@ class Product extends Model implements Purchasable, Cartable
 
     /**
      * Scope for booking products
+     *
+     * @param  Builder<static>  $query
+     * @return Builder<static>
      */
-    public function scopeBookings($query)
+    public function scopeBookings(Builder $query): Builder
     {
         return $query->where('type', ProductType::BOOKING->value);
     }

src/Models/ProductAction.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Models;
 
 use Illuminate\Database\Eloquent\Concerns\HasUuids;

src/Models/ProductActionRun.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Models;
 
 use Illuminate\Database\Eloquent\Model;

src/Models/ProductAttribute.php

@@ -1,7 +1,10 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Models;
 
+use Blax\Shop\Enums\ProductAttributeType;
 use Blax\Shop\Models\Product;
 use Illuminate\Database\Eloquent\Concerns\HasUuids;
 use Illuminate\Database\Eloquent\Model;
@@ -15,11 +18,15 @@ class ProductAttribute extends Model
         'product_id',
         'key',
         'value',
+        'type',
         'sort_order',
+        'meta',
     ];
 
     protected $casts = [
         'sort_order' => 'integer',
+        'type' => ProductAttributeType::class,
+        'meta' => 'array',
     ];
 
     protected $hidden = [

src/Models/ProductCategory.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Models;
 
 use Illuminate\Database\Eloquent\Concerns\HasUuids;

src/Models/ProductPrice.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Models;
 
 use Blax\Shop\Contracts\Cartable;
@@ -8,11 +10,42 @@ use Blax\Shop\Enums\BillingScheme;
 use Blax\Shop\Enums\PriceType;
 use Blax\Shop\Enums\RecurringInterval;
 use Blax\Workkit\Traits\HasMetaTranslation;
+use Illuminate\Database\Eloquent\Builder;
 use Illuminate\Database\Eloquent\Concerns\HasUuids;
 use Illuminate\Database\Eloquent\Factories\HasFactory;
 use Illuminate\Database\Eloquent\Model;
 use Illuminate\Database\Eloquent\Relations\HasMany;
+use Illuminate\Database\Eloquent\Relations\MorphTo;
 
+/**
+ * A price record attached to a {@see Purchasable} (usually a {@see Product},
+ * but anything can carry prices via the polymorphic `purchasable_*` columns).
+ *
+ * A single purchasable can carry several prices — one default, plus
+ * alternative tiers (bulk, region, customer-segment). Pricing follows the
+ * package-wide rule: amounts are integer cents, currency lives in a
+ * separate `currency` column, never inferred from the amount.
+ *
+ * @property string $id
+ * @property string $purchasable_type
+ * @property string $purchasable_id
+ * @property string|null $stripe_price_id
+ * @property string|null $name
+ * @property \Blax\Shop\Enums\PriceType $type
+ * @property string $currency  ISO 4217.
+ * @property float $unit_amount       Per-unit price in the smallest currency unit (cents). Cast to float for math.
+ * @property float|null $sale_unit_amount Sale price; defaults to `unit_amount` when unset.
+ * @property bool $is_default
+ * @property bool $active
+ * @property \Blax\Shop\Enums\BillingScheme $billing_scheme
+ * @property \Blax\Shop\Enums\RecurringInterval|null $interval
+ * @property int|null $interval_count
+ * @property int|null $trial_period_days
+ * @property \stdClass $meta
+ *
+ * @property-read Model $purchasable
+ * @property-read \Illuminate\Database\Eloquent\Collection<int, ProductPriceTier> $tiers
+ */
 class ProductPrice extends Model implements Cartable
 {
     use HasFactory, HasUuids, HasMetaTranslation;
@@ -48,17 +81,34 @@ class ProductPrice extends Model implements Cartable
         'trial_period_days' => 'integer',
     ];
 
-    public function purchasable()
+    /**
+     * The {@see Purchasable} this price belongs to (usually a {@see Product}).
+     *
+     * @return MorphTo<Model, $this>
+     */
+    public function purchasable(): MorphTo
     {
         return $this->morphTo();
     }
 
-    public function scopeIsActive($query)
+    /**
+     * Filter to only currently-active prices (default scope alternative).
+     *
+     * @param  Builder<self>  $query
+     * @return Builder<self>
+     */
+    public function scopeIsActive(Builder $query): Builder
     {
         return $query->where('active', true);
     }
 
-    public function getCurrentPrice(bool|null $sale_price = null): float
+    /**
+     * Resolve the unit price this record currently sells at.
+     *
+     * Returns the sale price when `$sale_price` is true *and* a
+     * `sale_unit_amount` is configured; otherwise the regular `unit_amount`.
+     */
+    public function getCurrentPrice(?bool $sale_price = null): float
     {
         if ($sale_price) {
             return $this->sale_unit_amount ?? $this->unit_amount;

src/Models/ProductPriceTier.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Models;
 
 use Blax\Shop\Database\Factories\ProductPriceTierFactory;

src/Models/ProductPurchase.php

@@ -1,13 +1,58 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Models;
 
 use Blax\Shop\Enums\PurchaseStatus;
 use Blax\Shop\Traits\HasBookingLifecycle;
 use Blax\Shop\Traits\HasLoanLifecycle;
+use Illuminate\Database\Eloquent\Builder;
 use Illuminate\Database\Eloquent\Concerns\HasUuids;
 use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\BelongsTo;
+use Illuminate\Database\Eloquent\Relations\HasManyThrough;
+use Illuminate\Database\Eloquent\Relations\MorphTo;
 
+/**
+ * Persisted record of "this purchasable was sold/loaned/booked to this purchaser".
+ *
+ * Single source of truth for any consumption event in the package:
+ *
+ *  - **E-commerce purchase**: status flows `CART → PENDING → COMPLETED`,
+ *    `from`/`until` left null.
+ *  - **Booking**: status `COMPLETED`, `from`/`until` carry the reserved window
+ *    (see {@see HasBookingLifecycle}).
+ *  - **Loan**: status `PENDING` until returned, then `COMPLETED`; `from`/`until`
+ *    are check-out and due dates (see {@see HasLoanLifecycle}).
+ *
+ * The polymorphic `purchasable_*` columns point at what was sold (typically a
+ * {@see Product} but can be any {@see \Blax\Shop\Contracts\Purchasable}). The
+ * polymorphic `purchaser_*` columns point at who bought it (typically a User,
+ * but any model).
+ *
+ * @property string $id
+ * @property \Blax\Shop\Enums\PurchaseStatus $status
+ * @property string|null $cart_id
+ * @property string|null $price_id
+ * @property string $purchasable_id
+ * @property string $purchasable_type
+ * @property string $purchaser_id
+ * @property string $purchaser_type
+ * @property int $quantity
+ * @property int $amount      Total amount charged, in cents.
+ * @property int $amount_paid Amount captured so far, in cents.
+ * @property string|null $charge_id
+ * @property \Illuminate\Support\Carbon|null $from   Booking start / loan check-out.
+ * @property \Illuminate\Support\Carbon|null $until  Booking end / loan due date.
+ * @property \stdClass $meta
+ *
+ * @property-read Model $purchasable
+ * @property-read Model $purchaser
+ * @property-read Product|null $product
+ * @property-read ProductPrice|null $price
+ * @property-read \Illuminate\Database\Eloquent\Collection<int, ProductActionRun> $actionRuns
+ */
 class ProductPurchase extends Model
 {
     use HasBookingLifecycle, HasLoanLifecycle, HasUuids;
@@ -45,25 +90,44 @@ class ProductPurchase extends Model
         $this->setTable(config('shop.tables.product_purchases', 'product_purchases'));
     }
 
-    public function purchasable()
+    /**
+     * What was sold/loaned/booked — usually a {@see Product} but anything
+     * implementing {@see \Blax\Shop\Contracts\Purchasable} qualifies.
+     *
+     * @return MorphTo<Model, $this>
+     */
+    public function purchasable(): MorphTo
     {
         return $this->morphTo('purchasable');
     }
 
-    public function purchaser()
+    /**
+     * Who made the purchase (typically a User), polymorphic.
+     *
+     * @return MorphTo<Model, $this>
+     */
+    public function purchaser(): MorphTo
     {
         return $this->morphTo('purchaser');
     }
 
-    public function product()
+    /**
+     * Convenience shortcut to a {@see Product} when the purchasable side IS
+     * a product; resolves through `purchasable_id` for the JOIN.
+     *
+     * @return BelongsTo<Product, $this>
+     */
+    public function product(): BelongsTo
     {
         return $this->belongsTo(config('shop.models.product', Product::class));
     }
 
     /**
      * The price this purchase bills against (see HasLoanLifecycle::calculateCost).
+     *
+     * @return BelongsTo<ProductPrice, $this>
      */
-    public function price()
+    public function price(): BelongsTo
     {
         return $this->belongsTo(
             config('shop.models.product_price', ProductPrice::class),
@@ -71,25 +135,45 @@ class ProductPurchase extends Model
         );
     }
 
-    public function user()
+    /**
+     * Resolve the purchaser as a User relation when the polymorphic type
+     * matches the configured auth model; returns null otherwise so callers
+     * can branch without an instanceof check on the resolved object.
+     *
+     * Note: returns a {@see MorphTo} (same instance as {@see self::purchaser()})
+     * so the caller can `->first()` / eager-load uniformly.
+     */
+    public function user(): ?MorphTo
     {
-        if ($this->purchasable_type === config('auth.providers.users.model', \Workbench\App\Models\User::class)) {
-            return $this->purchasable();
+        if ($this->purchaser_type === config('auth.providers.users.model', \Workbench\App\Models\User::class)) {
+            return $this->purchaser();
         }
         return null;
     }
 
-    public static function scopeFromCart($query, $cartId)
+    /**
+     * @param  Builder<self>  $query
+     * @return Builder<self>
+     */
+    public function scopeFromCart(Builder $query, string $cartId): Builder
     {
         return $query->where('cart_id', $cartId);
     }
 
-    public static function scopeInCart($query)
+    /**
+     * @param  Builder<self>  $query
+     * @return Builder<self>
+     */
+    public function scopeInCart(Builder $query): Builder
     {
         return $query->where('status', PurchaseStatus::CART->value);
     }
 
-    public static function scopeCompleted($query)
+    /**
+     * @param  Builder<self>  $query
+     * @return Builder<self>
+     */
+    public function scopeCompleted(Builder $query): Builder
     {
         return $query->where('status', PurchaseStatus::COMPLETED->value);
     }
@@ -127,7 +211,13 @@ class ProductPurchase extends Model
         });
     }
 
-    public function actionRuns()
+    /**
+     * Run-log of every {@see ProductAction} fired against the underlying
+     * product for this purchase (welcome email, fulfilment webhook, etc.).
+     *
+     * @return HasManyThrough<ProductActionRun, ProductAction, $this>
+     */
+    public function actionRuns(): HasManyThrough
     {
         return $this->hasManyThrough(
             ProductActionRun::class,

src/Models/ProductStock.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Models;
 
 use Blax\Shop\Enums\StockStatus;
@@ -312,7 +314,7 @@ class ProductStock extends Model
      * Scope: Get completed/available stock entries
      * These are physical stock changes (INCREASE/DECREASE) that have been finalized
      */
-    public static function scopeAvailable($query)
+    public function scopeAvailable($query)
     {
         return $query->where('status', StockStatus::COMPLETED->value);
     }
@@ -321,7 +323,7 @@ class ProductStock extends Model
      * Scope: Get active (pending) claimed stock entries
      * These represent stock currently claimed but not yet released
      */
-    public static function scopeAvailableClaims($query)
+    public function scopeAvailableClaims($query)
     {
         return $query->where('type', StockType::CLAIMED->value)->where('status', StockStatus::PENDING->value);
     }
@@ -350,7 +352,7 @@ class ProductStock extends Model
      * 
      * @param \DateTimeInterface $date The date to check availability for
      */
-    public static function scopeAvailableOnDate($query, \DateTimeInterface $date)
+    public function scopeAvailableOnDate($query, \DateTimeInterface $date)
     {
         return $query->where('type', StockType::CLAIMED->value)
             ->where('status', StockStatus::PENDING->value)

src/Services/CartService.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Services;
 
 use Blax\Shop\Models\Cart;

src/Services/PaymentProvider/PaymentProviderService.php

@@ -14,7 +14,7 @@ class PaymentProviderService
 {
     protected StripeService $stripeService;
 
-    public function __construct(StripeService $stripeService = null)
+    public function __construct(?StripeService $stripeService = null)
     {
         $this->stripeService = $stripeService ?? app(StripeService::class);
     }

src/Services/ShopService.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Services;
 
 use Blax\Shop\Enums\OrderStatus;
@@ -11,7 +13,7 @@ use Blax\Shop\Models\ProductCategory;
 use Blax\Shop\Models\ProductPurchase;
 use Illuminate\Database\Eloquent\Builder;
 use Illuminate\Database\Eloquent\Collection;
-use Illuminate\Support\Carbon;
+use Carbon\Carbon;
 
 class ShopService
 {

src/Services/StripeSyncService.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Services;
 
 use Blax\Shop\Exceptions\HasNoDefaultPriceException;

src/ShopServiceProvider.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop;
 
 use Blax\Shop\Console\Commands\ShopCleanupCartsCommand;

src/Traits/ChecksIfBooking.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Traits;
 
 use Blax\Shop\Enums\ProductType;

src/Traits/HasBookingLifecycle.php

@@ -1,7 +1,11 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Traits;
 
+use Illuminate\Database\Eloquent\Builder;
+
 /**
  * Booking lifecycle for a {@see \Blax\Shop\Models\ProductPurchase} row.
  *
@@ -9,6 +13,11 @@ namespace Blax\Shop\Traits;
  * time-bounded reservation. The trait is purchase-side — the corresponding
  * product-side concept is the BOOKING product type plus
  * {@see ChecksIfBooking}.
+ *
+ * # Host-model contract
+ *
+ * @property \Illuminate\Support\Carbon|null $from  Reservation window start.
+ * @property \Illuminate\Support\Carbon|null $until Reservation window end.
  */
 trait HasBookingLifecycle
 {
@@ -34,16 +43,22 @@ trait HasBookingLifecycle
 
     /**
      * Scope to date-bounded bookings only.
+     *
+     * @param  Builder<static>  $query
+     * @return Builder<static>
      */
-    public function scopeBookings($query)
+    public function scopeBookings(Builder $query): Builder
     {
         return $query->whereNotNull('from')->whereNotNull('until');
     }
 
     /**
      * Scope to bookings whose window is in the past.
+     *
+     * @param  Builder<static>  $query
+     * @return Builder<static>
      */
-    public function scopeEndedBookings($query)
+    public function scopeEndedBookings(Builder $query): Builder
     {
         return $query->bookings()->where('until', '<', now());
     }

src/Traits/HasBookingPriceCalculation.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Traits;
 
 use Carbon\Carbon;

src/Traits/HasCart.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Traits;
 
 use Blax\Shop\Exceptions\MultiplePurchaseOptions;

src/Traits/HasCategories.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Traits;
 
 use Blax\Shop\Models\ProductCategory;

src/Traits/HasChargingOptions.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Traits;
 
 use Illuminate\Database\Eloquent\Relations\MorphMany;

src/Traits/HasLoanLifecycle.php

@@ -1,12 +1,16 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Traits;
 
 use Blax\Shop\Enums\PurchaseStatus;
 use Blax\Shop\Events\LoanExtended;
 use Blax\Shop\Events\LoanReturned;
 use Blax\Shop\Models\ProductPrice;
-use Illuminate\Support\Carbon;
+use Illuminate\Database\Eloquent\Builder;
+use Illuminate\Database\Eloquent\Model;
+use Carbon\Carbon;
 
 /**
  * Loan / rental lifecycle for a {@see \Blax\Shop\Models\ProductPurchase} row.
@@ -27,6 +31,19 @@ use Illuminate\Support\Carbon;
  *
  * The product-side counterpart is {@see IsLoanableProduct}, which exposes a
  * `loan()` helper to create a purchase row pre-filled for this lifecycle.
+ *
+ * # Host-model contract
+ *
+ * Designed for {@see \Blax\Shop\Models\ProductPurchase}; expects these
+ * columns and accessors on the host:
+ *
+ * @property \Illuminate\Support\Carbon|null $from   Loan check-out timestamp.
+ * @property \Illuminate\Support\Carbon|null $until  Loan due timestamp (mutated by {@see self::extend()}).
+ * @property array<string, mixed>|\stdClass|null $meta Carries `returned_at` and `extensions_used` keys.
+ * @property \Blax\Shop\Enums\PurchaseStatus $status Set to `COMPLETED` on {@see self::markReturned()}.
+ * @property string|null $price_id        FK to {@see ProductPrice} used for cost calculation.
+ * @property-read ProductPrice|null $price  Eager-loadable price relation.
+ * @property-read Model|null $purchasable  The loaned item — typically a {@see IsLoanableProduct}-using model.
  */
 trait HasLoanLifecycle
 {
@@ -154,8 +171,11 @@ trait HasLoanLifecycle
 
     /**
      * Scope: loans currently in the borrower's hands (not returned).
+     *
+     * @param  Builder<static>  $query
+     * @return Builder<static>
      */
-    public function scopeActiveLoans($query)
+    public function scopeActiveLoans(Builder $query): Builder
     {
         return $query
             ->where('status', PurchaseStatus::PENDING->value)
@@ -164,16 +184,22 @@ trait HasLoanLifecycle
 
     /**
      * Scope: loans that have been handed back.
+     *
+     * @param  Builder<static>  $query
+     * @return Builder<static>
      */
-    public function scopeReturned($query)
+    public function scopeReturned(Builder $query): Builder
     {
         return $query->whereNotNull('meta->returned_at');
     }
 
     /**
      * Scope: loans past their due date and not yet returned.
+     *
+     * @param  Builder<static>  $query
+     * @return Builder<static>
      */
-    public function scopeOverdue($query)
+    public function scopeOverdue(Builder $query): Builder
     {
         return $query->activeLoans()->where('until', '<', now());
     }

src/Traits/HasOrders.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Traits;
 
 use Blax\Shop\Enums\OrderStatus;

src/Traits/HasPaymentMethods.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Traits;
 
 use Blax\Shop\Models\PaymentMethod;
@@ -69,7 +71,7 @@ trait HasPaymentMethods
      * @param bool $activeOnly Only return active payment methods
      * @return Collection
      */
-    public function paymentMethods(string $provider = null, bool $activeOnly = true): Collection
+    public function paymentMethods(?string $provider = null, bool $activeOnly = true): Collection
     {
         $identities = $this->paymentProviderIdentities();
 
@@ -156,7 +158,7 @@ trait HasPaymentMethods
      * @param string|null $provider
      * @return bool
      */
-    public function hasPaymentMethods(string $provider = null): bool
+    public function hasPaymentMethods(?string $provider = null): bool
     {
         return $this->paymentMethods($provider)->isNotEmpty();
     }

src/Traits/HasPrices.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Traits;
 
 use Blax\Shop\Exceptions\NotEnoughStockException;

src/Traits/HasPricingStrategy.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Traits;
 
 use Blax\Shop\Enums\PricingStrategy;

src/Traits/HasProductRelations.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Traits;
 
 use Blax\Shop\Enums\ProductRelationType;

src/Traits/HasShoppingCapabilities.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Traits;
 
 use Blax\Shop\Contracts\Purchasable;

src/Traits/HasStocks.php

@@ -1,10 +1,13 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Traits;
 
 use Blax\Shop\Enums\StockStatus;
 use Blax\Shop\Enums\StockType;
 use Blax\Shop\Exceptions\NotEnoughStockException;
+use Blax\Shop\Models\ProductStock;
 use Carbon\Carbon;
 use DateTimeInterface;
 use Illuminate\Database\Eloquent\Model;
@@ -12,29 +15,43 @@ use Illuminate\Database\Eloquent\Relations\HasMany;
 use Illuminate\Support\Facades\DB;
 
 /**
- * HasStocks Trait
+ * HasStocks — stock management surface for Product-shaped models.
  *
- * Provides stock management functionality to Product models.
+ * Provides:
+ *  - Basic stock operations: {@see self::increaseStock()}, {@see self::decreaseStock()},
+ *    {@see self::adjustStock()}.
+ *  - Reservation / booking claims via {@see self::claimStock()}.
+ *  - Date-based availability: {@see self::availableOnDate()},
+ *    {@see self::getAvailableForDateRange()}, {@see self::calendarAvailability()}.
+ *  - Low-stock detection: {@see self::isLowStock()} and the
+ *    {@see self::scopeLowStock()} query scope.
+ *  - Audit log writes via {@see self::logStockChange()} → `product_stock_logs`.
  *
- * Key Features:
- * - Basic stock operations (increase, decrease, adjust)
- * - Stock claims for bookings/reservations
- * - Date-based availability checking
- * - Low stock detection
- * - Stock movement logging
+ * # Stock calculation
  *
- * Usage:
- * - Add 'manage_stock' boolean column to products table
- * - Set manage_stock = true to enable stock tracking
- * - Use increaseStock/decreaseStock for inventory changes
- * - Use claimStock for reservations/bookings
- * - Use availableOnDate for date-based availability
+ *  - **Physical stock**: sum of all COMPLETED entries (positive INCREASE +
+ *    RETURN, negative DECREASE) that haven't expired.
+ *  - **Available stock**: physical stock, with active CLAIMED entries netted
+ *    out (their DECREASE side reduces availability while the PENDING claim
+ *    sits open).
+ *  - **Claimed stock**: sum of PENDING `CLAIMED` entries (returned as a
+ *    positive number by the getters).
+ *  - **Available on a given date**: physical stock at that date, minus claims
+ *    whose window covers that date.
  *
- * Stock Calculation:
- * - Physical Stock = Sum of all COMPLETED entries
- * - Available Stock = Physical Stock (accounts for pending claims via their DECREASE entries)
- * - Claimed Stock = Sum of PENDING claims
- * - Available on Date = Available Stock + All Claims - Claims Active on Date
+ * # Host-model contract
+ *
+ * The trait is designed to be applied to {@see \Blax\Shop\Models\Product} and
+ * its subclasses. It reads the columns declared below and the
+ * `singleProducts` relation supplied by {@see MayBePoolProduct} (when the
+ * host opts into pool support). Host models that don't manage stock should
+ * set `manage_stock = false`; in that mode every read returns
+ * `PHP_INT_MAX` and every mutation is a no-op returning `true`.
+ *
+ * @property string|int $id Primary key on the host model — used for cross-table FK writes.
+ * @property bool $manage_stock When `false`, stock methods short-circuit (treated as infinite supply).
+ * @property int|null $low_stock_threshold Threshold for {@see self::isLowStock()} / {@see self::scopeLowStock()}; null disables low-stock detection.
+ * @property \Illuminate\Database\Eloquent\Collection<int, \Blax\Shop\Models\Product> $singleProducts Pool-product relation supplied by {@see MayBePoolProduct}; only consulted in pool aggregation paths.
  */
 trait HasStocks
 {
@@ -48,7 +65,7 @@ trait HasStocks
     public function stocks(): HasMany
     {
         return $this->hasMany(
-            config('shop.models.product_stock', 'Blax\Shop\Models\ProductStock'),
+            config('shop.models.product_stock', ProductStock::class),
             'product_id'
         );
     }
@@ -59,7 +76,7 @@ trait HasStocks
     public function allStocks(): HasMany
     {
         return $this->hasMany(
-            config('shop.models.product_stock', 'Blax\Shop\Models\ProductStock'),
+            config('shop.models.product_stock', ProductStock::class),
             'product_id'
         )
             ->withExpired()
@@ -131,7 +148,7 @@ trait HasStocks
      * @return bool True if successful
      * @throws NotEnoughStockException If insufficient stock available
      */
-    public function decreaseStock(int $quantity = 1, Carbon|null $until = null): bool
+    public function decreaseStock(int $quantity = 1, ?Carbon $until = null): bool
     {
         if (!$this->manage_stock) {
             return true;
@@ -215,12 +232,12 @@ trait HasStocks
     public function adjustStock(
         StockType $type,
         int $quantity,
-        DateTimeInterface|null $until = null,
-        DateTimeInterface|null $from = null,
+        ?DateTimeInterface $until = null,
+        ?DateTimeInterface $from = null,
         ?StockStatus $status = null,
-        string|null $note = null,
-        Model|null $referencable = null
-    ) {
+        ?string $note = null,
+        ?Model $referencable = null
+    ): bool|\Blax\Shop\Models\ProductStock {
         if (!$this->manage_stock) {
             return false;
         }
@@ -298,7 +315,7 @@ trait HasStocks
             return null;
         }
 
-        $stockModel = config('shop.models.product_stock', 'Blax\Shop\Models\ProductStock');
+        $stockModel = config('shop.models.product_stock', ProductStock::class);
 
         return $stockModel::claim(
             $this,
@@ -451,6 +468,9 @@ trait HasStocks
      * Includes products with:
      * - Stock management disabled (always in stock), OR
      * - Stock management enabled AND available stock > 0
+     *
+     * @param  \Illuminate\Database\Eloquent\Builder<static>  $query
+     * @return \Illuminate\Database\Eloquent\Builder<static>
      */
     public function scopeInStock($query)
     {
@@ -470,6 +490,9 @@ trait HasStocks
      * - Stock management is enabled
      * - low_stock_threshold is set
      * - Available stock <= threshold
+     *
+     * @param  \Illuminate\Database\Eloquent\Builder<static>  $query
+     * @return \Illuminate\Database\Eloquent\Builder<static>
      */
     public function scopeLowStock($query)
     {
@@ -506,11 +529,11 @@ trait HasStocks
      * - Checking what's claimed but not released
      * - Managing active bookings
      * 
-     * @return \Illuminate\Database\Eloquent\Builder
+     * @return \Illuminate\Database\Eloquent\Builder<\Blax\Shop\Models\ProductStock>
      */
-    public function claims()
+    public function claims(): \Illuminate\Database\Eloquent\Builder
     {
-        $stockModel = config('shop.models.product_stock', 'Blax\Shop\Models\ProductStock');
+        $stockModel = config('shop.models.product_stock', ProductStock::class);
 
         return $stockModel::claims()
             ->willExpire()
@@ -676,9 +699,9 @@ trait HasStocks
      * Every other timestamp shows what total current availability is at that time.
      * 
      * @param  null|DateTimeInterface  $date
-     * @return array|int
+     * @return array<string, int>|int Map of HH:MM → available units, or PHP_INT_MAX when stock management is disabled.
      */
-    public function dayAvailability(?DateTimeInterface $date = null)
+    public function dayAvailability(?DateTimeInterface $date = null): array|int
     {
         // For pool products, aggregate availability from all single items
         if (method_exists($this, 'isPool') && $this->isPool()) {
@@ -794,7 +817,7 @@ trait HasStocks
         // Get all date keys from first single (they should all have the same dates)
         if (!empty($singleAvailabilities)) {
             $firstAvailability = $singleAvailabilities[0];
-            foreach ($firstAvailability['dates'] as $dateKey => $dayData) {
+            foreach (array_keys($firstAvailability['dates']) as $dateKey) {
                 $dayMin = 0;
                 $dayMax = 0;
 
@@ -827,9 +850,9 @@ trait HasStocks
      * Get day availability for pool products by aggregating all single items
      * 
      * @param  DateTimeInterface|null  $date
-     * @return array
+     * @return array<string, int>|int Map of HH:MM → available units across all single items, or PHP_INT_MAX when no managed single items exist.
      */
-    protected function getPoolDayAvailability(?DateTimeInterface $date = null): array
+    protected function getPoolDayAvailability(?DateTimeInterface $date = null): array|int
     {
         // Eager load single products if not already loaded
         if (!$this->relationLoaded('singleProducts')) {
@@ -900,13 +923,13 @@ trait HasStocks
      * @param  \Blax\Shop\Models\Cart|null  $cart Optional cart to subtract items from
      * @return int Available quantity (PHP_INT_MAX if unlimited)
      */
-    public function getHasMore($cart = null): int
+    public function getHasMore(?\Blax\Shop\Models\Cart $cart = null): int
     {
         // Try to get current cart from facade if not provided
         if ($cart === null) {
             try {
                 $cart = \Blax\Shop\Facades\Cart::current();
-            } catch (\Exception $e) {
+            } catch (\Exception) {
                 // No cart available, that's fine
                 $cart = null;
             }
@@ -944,9 +967,8 @@ trait HasStocks
      * Does NOT consider date-based availability - that's validated at checkout.
      * 
      * @param  \Blax\Shop\Models\Cart|null  $cart
-     * @return int
      */
-    protected function getPoolHasMore($cart = null): int
+    protected function getPoolHasMore(?\Blax\Shop\Models\Cart $cart = null): int
     {
         // Get total pool capacity (NOT date-restricted)
         if (method_exists($this, 'getPoolTotalCapacity')) {
@@ -992,12 +1014,11 @@ trait HasStocks
      * @param DateTimeInterface $from
      * @param DateTimeInterface $until
      * @param  \Blax\Shop\Models\Cart|null  $cart Optional cart to subtract items from
-     * @return int
      */
     public function getAvailableForDateRange(
         DateTimeInterface $from,
         DateTimeInterface $until,
-        $cart = null
+        ?\Blax\Shop\Models\Cart $cart = null
     ): int {
         if ($this->manage_stock === false) {
             return PHP_INT_MAX;

src/Traits/HasStripeAccount.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Traits;
 
 use Blax\Shop\Exceptions\MultiplePurchaseOptions;

src/Traits/IsLoanableProduct.php

@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Blax\Shop\Traits;
 
 use Blax\Shop\Enums\ProductStatus;