init with kirby, vue and pagedjs interactive

public/kirby/src/Form/Mixin/Validation.php

@@ -0,0 +1,117 @@
+<?php
+
+namespace Kirby\Form\Mixin;
+
+use Closure;
+use Exception;
+use Kirby\Form\Validations;
+use Kirby\Toolkit\A;
+use Kirby\Toolkit\I18n;
+use Kirby\Toolkit\V;
+
+/**
+ * @package   Kirby Form
+ * @author    Bastian Allgeier <bastian@getkirby.com>
+ * @link      https://getkirby.com
+ * @copyright Bastian Allgeier
+ * @license   https://opensource.org/licenses/MIT
+ */
+trait Validation
+{
+	/**
+	 * If `true`, the field has to be filled in correctly to be saved.
+	 */
+	protected bool $required;
+
+	/**
+	 * Runs all validations and returns an array of
+	 * error messages
+	 */
+	public function errors(): array
+	{
+		$validations = $this->validations();
+		$value       = $this->value();
+		$errors      = [];
+
+		// validate required values
+		if ($this->needsValue() === true) {
+			$errors['required'] = I18n::translate('error.validation.required');
+		}
+
+		foreach ($validations as $key => $validation) {
+			if (is_int($key) === true) {
+				// predefined validation
+				try {
+					Validations::$validation($this, $value);
+				} catch (Exception $e) {
+					$errors[$validation] = $e->getMessage();
+				}
+				continue;
+			}
+
+			if ($validation instanceof Closure) {
+				try {
+					$validation->call($this, $value);
+				} catch (Exception $e) {
+					$errors[$key] = $e->getMessage();
+				}
+			}
+		}
+
+		if (
+			empty($this->validate) === false &&
+			($this->isEmpty() === false || $this->isRequired() === true)
+		) {
+			$rules = A::wrap($this->validate);
+
+			$errors = [
+				...$errors,
+				...V::errors($value, $rules)
+			];
+		}
+
+		return $errors;
+	}
+
+	/**
+	 * Checks if the field is required
+	 */
+	public function isRequired(): bool
+	{
+		return $this->required;
+	}
+
+	/**
+	 * Checks if the field is invalid
+	 */
+	public function isInvalid(): bool
+	{
+		return $this->errors() !== [];
+	}
+
+	/**
+	 * Checks if the field is valid
+	 */
+	public function isValid(): bool
+	{
+		return $this->errors() === [];
+	}
+
+	public function required(): bool
+	{
+		return $this->required;
+	}
+
+	protected function setRequired(bool $required = false): void
+	{
+		$this->required = $required;
+	}
+
+	/**
+	 * Defines all validation rules
+	 */
+	protected function validations(): array
+	{
+		return [];
+	}
+}