fix: add preview capability (#7)

src/EnhancedMarkdown.php

@@ -4,12 +4,17 @@
 
 namespace Ardenthq\EnhancedMarkdown;
 
+use Laravel\Nova\Contracts\Previewable;
+use Laravel\Nova\Fields\Markdown\CommonMarkPreset;
+use Laravel\Nova\Fields\Markdown\DefaultPreset;
+use Laravel\Nova\Fields\Markdown\MarkdownPreset;
+use Laravel\Nova\Fields\Markdown\ZeroPreset;
 use Laravel\Nova\Fields\Trix;
 use Laravel\Nova\Trix\DeleteAttachments;
 use Laravel\Nova\Trix\DetachAttachment;
 use Laravel\Nova\Trix\DiscardPendingAttachments;
 
-class EnhancedMarkdown extends Trix
+class EnhancedMarkdown extends Trix implements Previewable
 {
     /**
      * The field's component.
@@ -32,6 +37,17 @@ class EnhancedMarkdown extends Trix
      */
     public $preset = 'default';
 
+    /**
+     * The built-in presets for the Markdown field.
+     *
+     * @var string[]
+     */
+    public $presets = [
+        'default'    => DefaultPreset::class,
+        'commonmark' => CommonMarkPreset::class,
+        'zero'       => ZeroPreset::class,
+    ];
+
     /**
      * Define the preset the field should use. Can be "commonmark", "zero", and "default".
      *
@@ -67,6 +83,31 @@ public function withFiles($disk = 'public', $path = '/')
         return $this;
     }
 
+    /**
+     * Return a preview for the given field value.
+     *
+     * @param  string  $value
+     * @return string
+     */
+    public function previewFor($value)
+    {
+        return $this->renderer()->convert($value);
+    }
+
+    /**
+     * @return MarkdownPreset
+     */
+    public function renderer()
+    {
+        /** @var string $preset */
+        $preset = $this->preset;
+
+        /** @var MarkdownPreset $renderer */
+        $renderer = new $this->presets[$preset]();
+
+        return $renderer;
+    }
+
     /**
      * Prepare the element for JSON serialization.
      *

tests/EnhancedMarkdownTest.php

@@ -43,3 +43,9 @@
 
     expect($field->preset)->toBe('commonmark');
 });
+
+it('generate previews', function () {
+    $field = new EnhancedMarkdown('content');
+
+    expect($field->previewFor('**markdown**'))->toContain('<p><strong>markdown</strong></p>');
+});