ReferencePlugin.php

<?php
/**
 * Reference
 *
 * Allows to serve an alphabetized and a hierarchical page of links to searches
 * for all item types and elements of all items of an Omeka instance.
 *
 * @copyright William Mayo 2011
 * @copyright Copyright Daniel Berthereau, 2014-2018
 * @copyright Copyright Daniele Binaghi, 2020
 * @license http://www.gnu.org/licenses/gpl-3.0.txt
 * @package Reference
 */

/**
 * The Reference plugin.
 * @package Omeka\Plugins\Reference
 */
class ReferencePlugin extends Omeka_Plugin_AbstractPlugin
{
	const REFERENCE_PATH_LIST = 'references';
	const REFERENCE_PATH_TREE = 'subjects/tree';

	/**
	 * @var array Hooks for the plugin.
	 */
	protected $_hooks = array(
		'initialize',
		'install',
		'uninstall',
		'config_form',
		'config',
		'define_routes',
		'public_head',
	);

	/**
	 * @var array Filters for the plugin.
	 */
	protected $_filters = array(
		'public_navigation_main',
		'public_navigation_items',
	);

	/**
	 * @var array Options and their default values.
	 */
	protected $_options = array(
		// 49 is the element id of Dublin Core Subject, forced during install.
		'reference_slugs' => array(
			'subject' => array(
				'id' => 49,
				'type' => 'Element',
				'label' => 'Subject',
				'active' => true,
			),
		),
		'reference_list_skiplinks' => true,
		'reference_list_alphabet' => '',
		'reference_list_headings' => true,
		'reference_link_to_single' => true,
		'reference_hide_empty' => false,
		'reference_show_count' => true,
		'reference_link_columns' => 1,
		'reference_tree_enabled' => false,
		'reference_tree_expanded' => true,
		'reference_tree_hierarchy' => '',
		'reference_query_type' => 'is exactly',
	);

	/**
	 * Add the translations.
	 */
	public function hookInitialize()
	{
		add_translation_source(dirname(__FILE__) . DIRECTORY_SEPARATOR . 'languages');
		add_shortcode('reference', array($this, 'shortcodeReference'));
		add_shortcode('subjects', array($this, 'shortcodeSubjects'));
	}

	/**
	 * Install the plugin.
	 */
	public function hookInstall()
	{
		// Keep old parameters.
		if (plugin_is_active('SubjectBrowse')) {
			$this->_options['reference_slugs']['subject']['active'] = get_option('subject_browse_list_enabled');
			$this->_options['reference_list_skiplinks'] = get_option('subject_browse_list_skiplinks');
			$this->_options['reference_list_headings'] = get_option('subject_browse_list_headings');
			$this->_options['reference_tree_enabled'] = get_option('subject_browse_tree_enabled');
			$this->_options['reference_tree_expanded'] = get_option('subject_browse_tree_expanded');
			$this->_options['reference_tree_hierarchy'] = get_option('subject_browse_tree_hierarchy');
		}

		$this->_options['reference_slugs'] = json_encode($this->_options['reference_slugs']);

		$this->_installOptions();

		$this->_updateSlugs();
	}

	/**
	 * Helper to create or update the default slugs with existing or new item
	 * types and elements.
	 *
	 * @return string
	 */
	protected function _updateSlugs()
	{
		$slugs = json_decode(get_option('reference_slugs'), true) ?: $this->_options['reference_slugs'];

		// Remove deleted records.
		foreach ($slugs as $slug => $slugData) {
			$record = $this->_db->getTable($slugData['type'])->find($slugData['id']);
			if (empty($record)) {
				unset($slugs[$slug]);
			}
		}

		// Data are in an array ordered by slug to be retrieved quickly, but it
		// implies to rebuild the list of ids by slug here.
		$idsBySlug = array();
		foreach ($slugs as $slug => $slugData) {
			$idsBySlug[$slug] = $slugData['id'];
		}

		// Initialize the empty slugs for item types and elements.
		$itemTypes = $this->_db->getTable('ItemType')->findPairsForSelectForm();

		$table = $this->_db->getTable('Element');
		$select = $table->getSelect()
			->order('elements.element_set_id')
			->order('ISNULL(elements.order)')
			->order('elements.order');
		$elements = $table->fetchObjects($select);

		$elementNamesById = array();
		foreach ($elements as $key => $element) {
			$elementSet = $element->getElementSet();
			// By default, no set name for Dublin Core.
			$slug = $elementSet->name == 'Dublin Core'
				? $element->name
				: $elementSet->name . ' : ' . $element->name;
			$elementNamesById[$element->id] = $slug;
		}

		foreach (array(
				'ItemType' => $itemTypes,
				'Element' => $elementNamesById,
			) as $type => $records) {
			foreach ($records as $id => $name) {
				$slugsFromId = array_keys($idsBySlug, $id);
				$slug = '';
				foreach ($slugsFromId as $slugFromId) {
					if ($slugs[$slugFromId]['type'] == $type) {
						$slug = $slugFromId;
						break;
					}
				}
				if (empty($slug)) {
					$newSlug = strtolower($name);
					$newSlug = str_replace(array(' ', ':', '/'), '-', $newSlug);
					$newSlug = preg_replace('/\-+/', '-', $newSlug);
					if (isset($idsBySlug[$newSlug])) {
						$newSlug = str_replace('_', '-', Inflector::underscore($type)) . '-' . $newSlug;
						$newSlug = preg_replace('/\-+/', '-', $newSlug);
						if (isset($idsBySlug[$newSlug])) {
							$newSlug .= '-' . substr(md5(rand()), 0, 7);
						}
					}
					// Keep only alphanumeric characters, underscores, dashes.
					$slugs[$newSlug]['id'] = $id;
					$slugs[$newSlug]['type'] = $type;
					$slugs[$newSlug]['label'] = $name;
					$slugs[$newSlug]['active'] = false;
					$idsBySlug[$newSlug] = $id;
				}
			}
		}

		// Order slugs by Item Types, then by Elements.
		$orderedSlugs = array();
		foreach (array(
				'ItemType' => $itemTypes,
				'Element' => $elementNamesById,
			) as $type => $list) {
			foreach ($list as $id => $name) {
				foreach ($slugs as $slug => $slugData) {
					if ($slugData['id'] == $id && $slugData['type'] == $type) {
						$orderedSlugs[$slug] = $slugData;
						unset($slugs[$slug]);
						break;
					}
				}
			}
		}

		set_option('reference_slugs', json_encode($orderedSlugs));
		return $orderedSlugs;
	}

	/**
	 * Uninstall the plugin.
	 */
	public function hookUninstall()
	{
		delete_option('reference_list_enabled');
		$this->_uninstallOptions();
	}

	/**
	 * Shows plugin configuration page.
	 */
	public function hookConfigForm($args)
	{
		$tables = array();
		foreach (array('ItemType', 'Element') as $type) {
			$tables[$type] = get_db()->getTable($type);
		}

		$view = $args['view'];
		echo $view->partial(
			'plugins/reference-config-form.php',
			array(
				'slugs' => $this->_updateSlugs(),
				'tables' => $tables,
		));
	}

	/**
	 * Processes the configuration form.
	 */
	public function hookConfig($args)
	{
		$post = $args['post'];

		// Check the list of slugs.
		$slugs = array();
		$totalSlugs = 0;
		foreach ($post['slugs'] as $type => $slugsById) {
			$slugs = array_merge($slugs, $slugsById);
			$totalSlugs += count($slugsById);
		}
		$slugs = array_filter($slugs);
		if (count($slugs) != $totalSlugs) {
			$msg = __('Some slugs are empty.');
			$msg .= ' ' . __('Changes were reverted.');
			throw new Omeka_Validate_Exception($msg);
		}
		$slugs = array_unique($slugs);
		if (count($slugs) != $totalSlugs) {
			$msg = __('Some slugs are not unique.');
			$msg .= ' ' . __('Changes were reverted.');
			throw new Omeka_Validate_Exception($msg);
		}

		// Rebuild the slugs data.
		$slugsData = array();
		$types = array();
		foreach ($post['slugs'] as $type => $slugsById) {
			foreach ($slugsById as $id => $slug) {
				$slugsData[$slug] = array();
				$slugsData[$slug]['id'] = $id;
				$slugsData[$slug]['type'] = $type;
				$slugsData[$slug]['label'] = $post['labels'][$type][$id];
				$slugsData[$slug]['active'] = $post['actives'][$type][$id];
				if ($slugsData[$slug]['active']) $types[$type] = true;
			}
		}

		unset($post['slugs']);
		unset($post['labels']);
		unset($post['actives']);
		$post['reference_slugs'] = $slugsData;

		foreach ($this->_options as $optionKey => $optionValue) {
			if (in_array($optionKey, array('reference_slugs'))) {
				$post[$optionKey] = json_encode($post[$optionKey]) ?: json_encode($optionValue);
			}
			if (isset($post[$optionKey])) {
				set_option($optionKey, $post[$optionKey]);
			}
		}
		
		$this->updatePublicNavigationMain($types);
	}

	/**
	 * Defines public routes
	 */
	public function hookDefineRoutes($args)
	{
		$args['router']->addConfig(new Zend_Config_Ini(
			dirname(__FILE__) . DIRECTORY_SEPARATOR . 'routes.ini', 
			'routes'
		));
	}

	public function hookPublicHead($args)
	{
		queue_css_file('reference');
	}

	/**
	 * Filter for public main navigation.
	 *
	 * @return nav
	 */
	public function filterPublicNavigationMain($nav)
	{
		$nav[] = array(
			'label' => __('References'),
			'uri' => url(array(), 'reference_base'),
		);

		if (get_option('reference_tree_enabled')) {
			$nav[] = array(
				'label' => __('Subjects Tree'),
				'uri' => url(array(), 'reference_tree'),
			);
		}
		return $nav;
	}

	/**
	 * Filter for public navigation items.
	 *
	 * @return nav
	 */
	public function filterPublicNavigationItems($nav)
	{
		$types = $this->getReferenceTypes();
		if (isset($types['Element']) && $types['Element'] && count($types) == 1) {
			$label = __('Browse Metadata');
		} elseif (isset($types['ItemType']) && $types['ItemType'] && count($types) == 1) {
			$label = __('Browse Item Types');
		} else {
			$label = __('Browse References');
		}

		$nav['Browse References'] = array(
			'label' => $label,
			'uri' => url(array(), 'reference_base'),
		);

		if (get_option('reference_tree_enabled')) {
			$nav['Hierarchy of Subjects'] = array(
				'label' => __('Hierarchy of Subjects'),
				'uri' => url(array(), 'reference_tree'),
			);
		}

		return $nav;
	}

	/**
	 * Shortcode for adding list of references.
	 *
	 * @param array $args
	 * @param Omeka_View $view
	 * @return string
	 */
	public function shortcodeReference($args, $view)
	{
		$args['view'] = $view;
		if (empty($args['slug'])) {
			return;
		}
		$references = $view->reference()->getList($args['slug']);
		foreach ($args as &$arg) {
			// Set true values.
			if ($arg == 'true') {
				$arg = true;
			}
			// Set false values.
			elseif ($arg == 'false') {
				$arg = false;
			}
		}
		return $view->reference()->displayList($references, $args);
	}

	/**
	 * Shortcode for adding tree of subjects.
	 *
	 * @param array $args
	 * @param Omeka_View $view
	 * @return string
	 */
	public function shortcodeSubjects($args, $view)
	{
		$args['view'] = $view;
		$subjects = $view->reference()->getTree();
		foreach ($args as &$arg) {
			// Set true values.
			if ($arg == 'true') {
				$arg = true;
			}
			// Set false values.
			elseif ($arg == 'false') {
				$arg = false;
			}
		}
		return $view->reference()->displayTree($subjects, $args);
	}
	
    /**
     * Get the list of active reference types (Item Types, Metadata) 
     *
     * @return array or null
     */
	public function getReferenceTypes()
	{
		$slugs = json_decode(get_option('reference_slugs'), true) ?: array();
        if (!empty($slugs)) {
			// Remove disabled slugs.
			foreach ($slugs as $slug => $slugData) {
				if (empty($slugData['active'])) {
					unset($slugs[$slug]);
				}
			}
		}

		if (!empty($slugs)) {
			$types = array();
			foreach ($slugs as $slug => $slugData) {
				$types[$slugData['type']] = true;
			}
			return $types;
		} else {
			return null;
		}
	}

	public function updatePublicNavigationMain($types)
	{
		if (count($types) == 1 && isset($types['Element']) && $types['Element']) {
			$label = 'Metadata';
		} elseif (count($types) == 1 && isset($types['ItemType']) && $types['ItemType']) {
			$label = 'Item Types';
		} else {
			$label = 'References';
		}

		$navItems = json_decode(get_option('public_navigation_main'), true) ?: array();
		foreach ($navItems AS $key=>$navItem) {
			if ($navItem['uid'] == '/' . self::REFERENCE_PATH_LIST) {
				if ($navItem['label'] != $label) {
					$navItems[$key]['label'] = $label;
					$optionValue = json_encode($navItems);
					set_option('public_navigation_main', $optionValue);
					return true;
				}
			}
		}
	}
}