Update 01-overview.md

Author: danharrin

packages/schemas/docs/04-layouts/01-overview.md

@@ -1,9 +1,10 @@
 ---
 title: Overview
 ---
+import UtilityInjection from "@components/UtilityInjection.astro"
 ## Overview
 
-Filament schemas are not limited to just displaying [form fields](../../forms/fields) and [infolist entries](../../infolists/entries). You can also use "layout components" to organize them into an infinitely nestable structure.
+Filament schemas are not limited to just displaying [form fields](../forms) and [infolist entries](../infolists). You can also use "layout components" to organize them into an infinitely nestable structure.
 
 Layout component classes can be found in the `Filament\Schemas\Components` namespace. They reside within the schema array of components.
 
@@ -28,33 +29,141 @@ Filament ships with some layout components, suitable for arranging your componen
 - [Wizard](wizard)
 - [Section](section)
 - [Split](split)
-- [Placeholder](placeholder)
 
-You may also [create your own custom layout components](custom) to organize fields however you wish.
+You may also [create your own custom layout components](custom) to organize schemas however you wish.
 
-## Setting an ID
+## Adding extra HTML attributes to a layout component
 
-You may define an ID for the component using the `id()` method:
+You can pass extra HTML attributes to the component via the `extraAttributes()` method, which will be merged onto its outer HTML element. The attributes should be represented by an array, where the key is the attribute name and the value is the attribute value:
 
 ```php
 use Filament\Schemas\Components\Section;
 
 Section::make()
-    ->id('main-section')
+    ->extraAttributes(['class' => 'custom-section-style'])
 ```
 
-## Adding extra HTML attributes
+<UtilityInjection set="formFields" version="4.x">As well as allowing a static value, the `extraAttributes()` method also accepts a function to dynamically calculate it. You can inject various utilities into the function as parameters.</UtilityInjection>
+
+By default, calling `extraAttributes()` multiple times will overwrite the previous attributes. If you wish to merge the attributes instead, you can pass `merge: true` to the method.
 
-You can pass extra HTML attributes to the component, which will be merged onto the outer DOM element. Pass an array of attributes to the `extraAttributes()` method, where the key is the attribute name and the value is the attribute value:
+## Component utility injection
+
+The vast majority of methods used to configure entries accept functions as parameters instead of hardcoded values:
 
 ```php
+use App\Models\User;
+use Filament\Schemas\Components\Grid;
 use Filament\Schemas\Components\Section;
 
+Grid::make(fn (): array => [
+    'lg' => auth()->user()->isAdmin() ? 4 : 6,
+])->schema([
+    // ...
+])
+
 Section::make()
-    ->extraAttributes(['class' => 'custom-section-style'])
+    ->heading(fn (): string => auth()->user()->isAdmin() ? 'Admin Dashboard' : 'User Dashboard')
+    ->schema([
+        // ...
+    ])
 ```
 
-Classes will be merged with the default classes, and any other attributes will override the default attributes.
+This alone unlocks many customization possibilities.
+
+The package is also able to inject many utilities to use inside these functions, as parameters. All customization methods that accept functions as arguments can inject utilities.
+
+These injected utilities require specific parameter names to be used. Otherwise, Filament doesn't know what to inject.
+
+### Injecting the state of another component
+
+You may also retrieve the state (value) of a form field or infolist entry from within a callback, using a `$get` parameter:
+
+```php
+use Filament\Schemas\Components\Utilities\Get;
+
+function (Get $get) {
+    $email = $get('email'); // Store the value of the `email` entry in the `$email` variable.
+    //...
+}
+```
+
+### Injecting the current Eloquent record
+
+You may retrieve the Eloquent record for the current schema using a `$record` parameter:
+
+```php
+use Illuminate\Database\Eloquent\Model;
+
+function (?Model $record) {
+    // ...
+}
+```
+
+### Injecting the current operation
+
+If you're writing a schema for a panel resource or relation manager, and you wish to check if a schema is `create`, `edit` or `view`, use the `$operation` parameter:
+
+```php
+function (string $operation) {
+    // ...
+}
+```
+
+<Aside variant="info">
+    You can manually set a schema's operation using the `$schema->operation()` method.
+</Aside>
+
+### Injecting the current Livewire component instance
+
+If you wish to access the current Livewire component instance, define a `$livewire` parameter:
+
+```php
+use Livewire\Component;
+
+function (Component $livewire) {
+    // ...
+}
+```
+
+### Injecting the current component instance
+
+If you wish to access the current component instance, define a `$component` parameter:
+
+```php
+use Filament\Schemas\Components\Component;
+
+function (Component $component) {
+    // ...
+}
+```
+
+### Injecting multiple utilities
+
+The parameters are injected dynamically using reflection, so you are able to combine multiple parameters in any order:
+
+```php
+use Filament\Schemas\Components\Utilities\Get;
+use Filament\Schemas\Components\Utilities\Set;
+use Livewire\Component as Livewire;
+
+function (Livewire $livewire, Get $get, Set $set) {
+    // ...
+}
+```
+
+### Injecting dependencies from Laravel's container
+
+You may inject anything from Laravel's container like normal, alongside utilities:
+
+```php
+use Filament\Schemas\Components\Utilities\Set;
+use Illuminate\Http\Request;
+
+function (Request $request, Set $set) {
+    // ...
+}
+```
 
 ## Global settings
 
@@ -69,7 +178,7 @@ Section::configureUsing(function (Section $section): void {
 });
 ```
 
-Of course, you are still able to overwrite this on each field individually:
+Of course, you are still able to overwrite this on each component individually:
 
 ```php
 use Filament\Schemas\Components\Section;