N°8772 - Form dependencies manager implementation

sources/Forms/Dependency/DependencyHandler.php

@@ -0,0 +1,173 @@
+<?php
+
+namespace Combodo\iTop\Forms\Dependency;
+
+use Exception;
+use Symfony\Component\Form\Event\PostSetDataEvent;
+use Symfony\Component\Form\Event\PostSubmitEvent;
+use Symfony\Component\Form\FormBuilderInterface;
+use Symfony\Component\Form\FormEvent;
+use Symfony\Component\Form\FormEvents;
+use Symfony\Component\Form\FormInterface;
+
+class DependencyHandler
+{
+	/** @var array dépendencies descriptions stored on builder add */
+	private array $aDependenciesDescription = [];
+
+	/** @var array dependencies map computed on form pre set data */
+	private array $aDependenciesMap = [];
+
+	/**
+	 * Constructor.
+	 *
+	 * @param FormBuilderInterface $builder
+	 */
+	public function __construct(public FormBuilderInterface $builder)
+	{
+		// Initialize the dependencies listeners once the form is built
+		$builder->addEventListener(FormEvents::PRE_SET_DATA, function (FormEvent $event) {
+			$oForm = $event->getForm();
+			$this->InitializeDependenciesMap($oForm);
+		});
+	}
+
+	/**
+	 *Initialize the dependencies map and register listeners on the dependencies inputs.
+	 *
+	 * @param FormInterface $oForm
+	 *
+	 * @return void
+	 */
+	private function InitializeDependenciesMap(FormInterface $oForm): void
+	{
+
+		/** iterate throw dependencies descriptions... @var DependencyDescription $oDependencyDescription */
+		foreach ($this->aDependenciesDescription as $oDependencyDescription) {
+
+			/** iterate throw dependencies items... */
+			foreach ($oDependencyDescription->aDependencies as $sInput => $aData) {
+
+				// get the dependency field name
+				$sDependency = $aData['source'];
+
+				// get the field input name
+				$sOutput = array_key_exists('output', $aData) ? $aData['output'] : null;
+
+				// add the dependency to the map
+				if(!array_key_exists($sDependency, $this->aDependenciesMap)){
+					$this->aDependenciesMap[$sDependency] = [];
+				}
+				$this->aDependenciesMap[$sDependency][] = ['description' => $oDependencyDescription, 'input' => $sInput, 'output' => $sOutput];
+			}
+		}
+
+		/** iterate throw dependencies... */
+		foreach (array_keys($this->aDependenciesMap) as $sDependency){
+
+			// Listen the dependency
+			$this->builder->get($sDependency)->addEventListener(FormEvents::POST_SET_DATA, $this->GetEventListeningCallback());
+			$this->builder->get($sDependency)->addEventListener(FormEvents::POST_SUBMIT, $this->GetEventListeningCallback());
+
+		}
+
+	}
+
+	/**
+	 * Add a dependency description.
+	 *
+	 * @param DependencyDescription $oDependencyDescription
+	 *
+	 * @return void
+	 */
+	public function AddDependencyDescription(DependencyDescription $oDependencyDescription): void
+	{
+		$this->aDependenciesDescription[] = $oDependencyDescription;
+	}
+
+	/**
+	 * The event handling callback.
+	 *
+	 * @return callable
+	 */
+	private function GetEventListeningCallback(): callable
+	{
+		return function (FormEvent $event){
+
+			// Get the event type
+			$sEventType = $this->GetEventType($event);
+
+			// Get the form
+			$oForm = $event->getForm();
+
+			/** Iterate throw dependencies map... */
+			foreach ($this->aDependenciesMap[$event->getForm()->getName()] as $aData){
+
+				// Get the map data
+				$oDependencyDescription = $aData['description'];
+				$sInput = $aData['input'];
+				$sOutput = $aData['output'];
+
+				// Compute output value
+				$oValue = $event->getData();
+				if(array_key_exists('outputs', $event->getForm()->getConfig()->getOptions())){
+					$aOutputs = $event->getForm()->getConfig()->getOptions()['outputs'];
+					if(array_key_exists($sOutput, $aOutputs)){
+						$oValue = $aOutputs[$sOutput]($oValue);
+					}
+				}
+
+				// Store the input value
+				$oDependencyDescription->SetData($sEventType, $sInput, $oValue);
+
+				// When dependencies met, add the dependent field if not already done
+				if(!$oDependencyDescription->IsAdded() && $oDependencyDescription->IsDataReady($sEventType)) {
+
+					// Get the dependent field options
+					$aOptions = $oDependencyDescription->options;
+
+					// Add the listener callback to the dependent field if it is also a dependency for another field
+					if(is_string($oDependencyDescription->child) && array_key_exists($oDependencyDescription->child, $this->aDependenciesMap)) {
+						$aOptions = array_merge($aOptions, [
+							'listener_callback' => $this->GetEventListeningCallback(),
+						]);
+					}
+
+					// Add the dependent field to the form
+					$oForm->getParent()->add($oDependencyDescription->child, $oDependencyDescription->type, array_merge($aOptions, $oDependencyDescription->type::GetOptionsFromInputs($oDependencyDescription->GetData($sEventType))));
+
+					// Mark the dependency as added
+					$oDependencyDescription->SetAdded(true);
+				}
+			}
+
+		};
+
+	}
+
+	/**
+	 * Get the event type.
+	 *
+	 * @param FormEvent $event
+	 *
+	 * @return string
+	 * @throws Exception
+	 */
+	private function GetEventType(FormEvent $event): string
+	{
+		if($event instanceof PostSetDataEvent) {
+			return FormEvents::POST_SET_DATA;
+		}
+		else if($event instanceof PostSubmitEvent) {
+			return FormEvents::POST_SUBMIT;
+		}
+
+		throw new Exception(sprintf("Unknown event type %s", get_class($event)));
+	}
+
+
+
+
+
+
+}