Updated dependencies

composer.json

@@ -13,8 +13,9 @@
         "psr-4": {"InvoiceNinja\\Sdk\\": "src/"}
     },
     "require": {
-        "php": "^7.4|^8.0|^8.1",
-        "guzzlehttp/guzzle": "^7.3"
+        "php": "^8.1|^8.2",
+        "guzzlehttp/guzzle": "^7.5",
+        "nesbot/carbon": "^2.66"
     },
     "require-dev": {
         "fakerphp/faker": "^1.16",

src/Exceptions/ApiException.php

@@ -32,6 +32,7 @@ protected static function parseResponseBody($response)
         $body = (string) $response->getBody();
         $error = "";
         $object = @json_decode($body);
+        $error_array = [];
 
         if(property_exists($object, "message"))
             $error = $object->message;
@@ -40,10 +41,10 @@ protected static function parseResponseBody($response)
         {
             $properties = array_keys(get_object_vars($object->errors));
 
-            if(is_array($properties))
+            if(is_array($properties) && count($properties) >=1)
                 $error_array = $object->errors->{$properties[0]};
 
-            if(is_array($error_array))
+            if(is_array($error_array) && count($error_array) >=1)
                 $error = $error_array[0];
 
         }

src/Exceptions/ModelValidationException.php

@@ -0,0 +1,16 @@
+<?php
+/**
+ * Invoice Ninja (https://invoiceninja.com).
+ *
+ * @link https://github.com/invoiceninja/sdk-php source repository
+ *
+ * @copyright Copyright (c) 2022. Invoice Ninja LLC (https://invoiceninja.com)
+ *
+ * @license https://opensource.org/licenses/MIT
+ */
+
+namespace InvoiceNinja\Sdk\Exceptions;
+
+class ModelValidationException extends \Exception
+{
+}

src/Models/BaseModel.php

@@ -0,0 +1,87 @@
+<?php
+/**
+ * Invoice Ninja (https://invoiceninja.com).
+ *
+ * @link https://github.com/invoiceninja/sdk-php source repository
+ *
+ * @copyright Copyright (c) 2022. Invoice Ninja LLC (https://invoiceninja.com)
+ *
+ * @license https://opensource.org/licenses/MIT
+ */
+
+namespace InvoiceNinja\Sdk\Models;
+
+use InvoiceNinja\Sdk\Exceptions\ModelValidationException;
+
+class BaseModel
+{
+	private array $validation_errors = [];
+
+    public function validate(): bool | ModelValidationException
+    {
+        $this->resetValidationErrors();
+
+        foreach($this->rules as $key => $rule)
+        {
+
+            switch($rule)
+            {
+                case 'required':
+                    isset($this->{$key}) ?: $this->setValidationErrors(["error" => "{$this->model} - `{$key}` must be set", "code" => 422]);
+                    break;
+                case 'date':
+                    isset($this->{$key}) ? $this->checkDate($key) : true;
+                    break;
+                default:
+                	$this->setValidationErrors(["error" => "{$this->model} - Unknown validation rule `{$rule}` for property `{$key}`", "code" => 500]);
+
+            }
+
+        }
+
+        if(count($this->getValidationErrors()) == 0)
+        	return true;
+
+        throw new ModelValidationException($this->getValidationErrors()[0]["error"] ,$this->getValidationErrors()[0]["code"]);
+    }
+
+    private function resetValidationErrors()
+    {
+        $this->validation_errors = [];
+
+        return $this;
+    }
+
+    private function setValidationErrors($error): self
+    {
+        $this->validation_errors[] = $error;
+
+        return $this;
+    }
+
+    public function getValidationErrors(): array
+    {
+        return $this->validation_errors;
+    }
+
+    public function checkDate(string $date_field): bool
+    {
+
+        try {
+
+            $parsed_date = \Carbon\Carbon::parse($this->{$date_field});
+            $this->{$date_field} = $parsed_date->format('Y-m-d');
+
+            return true;
+        }
+        catch(\Exception $e) {
+            $this->setValidationErrors([$date_field => "Invalid date format for field {$date_field} - '{$this->{$date_field}}'"]);
+            return false;
+        }
+    }
+
+
+
+
+
+}