class IconExtractorBase

abstract class IconExtractorBase extends PluginBase implements IconExtractorInterface, PluginWithFormsInterface {
    use PluginWithFormsTrait;
    // Remove internal values and allow extractor to add any needed values.
    private const DEFINITION_REMOVE = [
        'enabled',
        'template',
        'description',
        'links',
        'config',
    ];
    
    /**
     * {@inheritdoc}
     */
    public function label() : string {
        return (string) $this->pluginDefinition['label'];
    }
    
    /**
     * {@inheritdoc}
     */
    public function description() : string {
        return (string) $this->pluginDefinition['description'];
    }
    
    /**
     * {@inheritdoc}
     */
    public function buildConfigurationForm(array $form, FormStateInterface $form_state) : array {
        if (!isset($this->configuration['settings'])) {
            return $form;
        }
        return IconExtractorSettingsForm::generateSettingsForm($this->configuration['settings'], $form_state);
    }
    
    /**
     * {@inheritdoc}
     */
    public function validateConfigurationForm(array &$form, FormStateInterface $form_state) : void {
    }
    
    /**
     * {@inheritdoc}
     */
    public function submitConfigurationForm(array &$form, FormStateInterface $form_state) : void {
    }
    
    /**
     * {@inheritdoc}
     */
    public function loadIcon(array $icon_data) : ?IconDefinitionInterface {
        if (!isset($icon_data['icon_id']) || empty($icon_data['icon_id'])) {
            return NULL;
        }
        return $this->createIcon($icon_data['icon_id'], $icon_data['source'] ?? '', $icon_data['group'] ?? NULL);
    }
    
    /**
     * {@inheritdoc}
     */
    public function createIcon(string $icon_id, ?string $source = NULL, ?string $group = NULL, ?array $data = NULL) : IconDefinitionInterface {
        if (!isset($this->configuration['template'])) {
            throw new IconPackConfigErrorException(sprintf('Missing `template` in your definition, extractor %s requires this value.', $this->getPluginId()));
        }
        // Clean unused pack definition values as they will be passed to the context
        // of the Twig.
        $data_definition = array_diff_key($this->configuration, array_flip(self::DEFINITION_REMOVE));
        return IconDefinition::create($this->configuration['id'], $icon_id, $this->configuration['template'], $source, $group, $data ? array_merge($data, $data_definition) : $data_definition);
    }

}