feat: implement Notion-like LMS (Course Player, Exam, Certificate) with R2 integration

app/Filament/Admin/Resources/Lessons/Schemas/LessonForm.php

@@ -27,12 +27,37 @@ class LessonForm
                 Textarea::make('content')
                     ->columnSpanFull(),
                 TextInput::make('video_url')
-                    ->url(),
-                TextInput::make('content_pdf'),
+                    ->url()
+                    ->placeholder('https://youtube.com/watch?v=...')
+                    ->visible(fn (callable $get) => $get('type') === 'video'),
+                    
+                \Filament\Forms\Components\SpatieMediaLibraryFileUpload::make('content_pdf')
+                    ->collection('content_pdf')
+                    ->disk('r2')
+                    ->visibility('public')
+                    ->acceptedFileTypes(['application/pdf'])
+                    ->label('Upload PDF Material')
+                    ->visible(fn (callable $get) => $get('type') === 'pdf'),
+
+                // Legacy URL input if needed, or remove. Keeping it hidden if empty? 
+                // Let's keep it as an alternative or just replace it.
+                // Assuming we want to fully switch to upload:
+                // TextInput::make('content_pdf')->label('PDF URL (Legacy)'),
+
                 TextInput::make('duration_seconds')
                     ->required()
                     ->numeric()
-                    ->default(0),
+                    ->default(0)
+                    ->suffix('Seconds'),
+
+                \Filament\Forms\Components\SpatieMediaLibraryFileUpload::make('attachments')
+                    ->collection('attachments')
+                    ->disk('r2')
+                    ->visibility('public')
+                    ->multiple()
+                    ->downloadable()
+                    ->label('Attachments (Downloadable Resources)'),
+
                 Toggle::make('is_free_preview')
                     ->required(),
                 TextInput::make('order_index')
@@ -40,7 +65,8 @@ class LessonForm
                     ->numeric()
                     ->default(0),
                 Textarea::make('metadata')
-                    ->columnSpanFull(),
+                    ->columnSpanFull()
+                    ->rows(5),
                 Select::make('vocabularies')
                     ->relationship('vocabularies', 'word')
                     ->multiple()