<?php namespace ProcessWire;

/**
 * An Inputfield for handling relational Page inputs
 *
 * Delegates the actual input control to a user-defined Inputfield derived from InputfieldSelect
 * 
 * @method PageArray|null getSelectablePages(Page $page)
 * @method PageArray findPagesCode(Page $page)
 * 
 * Can be accessed from $this or from $field:
 * 
 * @property int $template_id
 * @property array $template_ids
 * @property int $parent_id
 * @property string $inputfield
 * @property string $labelFieldName Field name to use for label (note: this will be "." if $labelFieldFormat is in use).
 * @property string $labelFieldFormat Formatting string for $page->getMarkup() as alternative to $labelFieldName
 * @property string $findPagesCode
 * @property string $findPagesSelector
 * @property string $findPagesSelect Same as findPageSelector, but configured interactively with InputfieldSelector .
 * @property int|bool $addable
 * @property int|bool $allowUnpub
 * @property int $derefAsPage
 * @property array $inputfieldClasses
 * 
 * @method string renderAddable()
 * @method void processInputAddPages(WireInputData $input)
 * 
 * @todo make findPagesCode disabled by default
 * 
 */
class InputfieldPage extends Inputfield implements ConfigurableModule {
	
	public static function getModuleInfo() {
		return array(
			'title' => 'Page',
			'version' => 107,
			'summary' => 'Select one or more pages',
			'permanent' => true,
		);
	}

	/**
	 * @var Inputfield|null
	 * 
	 */
	protected $inputfieldWidget = null;

	/**
	 * Default options for Inputfield classes
	 * 
	 * @var array
	 * 
	 */
	protected static $defaultInputfieldClasses = array(
		'InputfieldSelect',
		'InputfieldSelectMultiple',
		'InputfieldCheckboxes',
		'InputfieldRadios', 
		'InputfieldAsmSelect',
		'InputfieldPageListSelect', 
		'InputfieldPageAutocomplete',
		);

	/**
	 * Default configuration values
	 * 
	 * @var array
	 * 
	 */
	protected static $defaultConfig = array(
		'parent_id' => 0,
		'template_id' => 0,
		'template_ids' => array(), 
		'inputfield' => '', 
		'labelFieldName' => '',
		'labelFieldFormat' => '',
		'findPagesCode' => '',
		'findPagesSelect' => '',
		'findPagesSelector' => '',
		'derefAsPage' => 0, 
		'addable' => 0,
		'allowUnpub' => 0, // This option configured by FieldtypePage:Advanced
		); 

	/**
	 * Contains true when this module is in configuration state (via it's getConfigInputfields function)
	 *
	 */
	protected $configMode = false;

	/**
	 * True when processInput is currently processing
	 * 
	 */
	protected $processInputMode = false;

	/**
	 * True when in renderValue mode
	 * 
	 * @var bool
	 * 
	 */
	protected $renderValueMode = false;

	/**
	 * PageArray of pages that were added in the request
	 * 
	 * @var PageArray|null
	 *
	 */
	protected $pagesAdded;

	/**
	 * CSS class names added to the Inputfield (will be applied to delegate Inputfield)
	 * 
	 * @var array
	 * 
	 */
	protected $classesAdded = array();

	/**
	 * Construct
	 * 
	 */
	public function __construct() {
		$this->set('inputfieldClasses', self::$defaultInputfieldClasses); 
		parent::__construct();
	}

	/**
	 * Init (populate default values)
	 * 
	 */
	public function init() {
		foreach(self::$defaultConfig as $key => $value) {
			$this->set($key, $value);
		}
		$this->attr('value', $this->wire('pages')->newPageArray()); 
		parent::init();
	}

	/**
	 * Add a CSS class name (extends Inputfield::addClass)
	 * 
	 * @param array|string $class
	 * @param string $property
	 * @return InputfieldPage|Inputfield
	 * 
	 */
	public function addClass($class, $property = 'class') {
		if($property == 'class') {
			$this->classesAdded[] = $class; 
		}
		return parent::addClass($class, $property); 
	}

	/**
	 * Set an input attribute
	 * 
	 * Overrides Inputfield::setAttribute() to capture 'value' attribute
	 * 
	 * @param array|string $key
	 * @param array|int|string $value
	 * @return InputfieldPage|Inputfield
	 * 
	 */
	public function setAttribute($key, $value) {

		if($key == 'value') { 
			if(is_string($value) || is_int($value)) {
				// setting the value attr from a string, whether 1234 or 123|446|789

				if(ctype_digit("$value")) {
					// i.e. "1234"
					$a = $this->wire('pages')->newPageArray();
					$page = $this->wire('pages')->get((int) $value);
					if($page->id) $a->add($page);
					$value = $a; 

				} else if(strpos($value, '|') !== false) {
					// i.e. 123|456|789
					$a = $this->wire('pages')->newPageArray();
					foreach(explode('|', $value) as $id) {
						if(!ctype_digit("$id")) continue; 
						$page = $this->wire('pages')->get((int) $id);
						if($page->id) $a->add($page);
					}
					$value = $a; 
				} else {
					// unrecognized format
				}
			}

		}
		return parent::setAttribute($key, $value);
	}

	/**
	 * Is the given $page valid for the given $field?
	 * 
	 * Note that this validates all but findPagesCode (eval) based page selections. 
	 * This is primarily for use by FieldtypePage, but kept here since the config options
	 * it uses to check are part of this module's config. 
	 * 
	 * If false is returned and given an $editPage, a reason for the false will be populated
	 * to the $editPage->_isValidPage property. 
	 * 
	 * @param Page $page
	 * @param Field|string|int $field Field instance of field name (string) or ID
	 * @param Page $editPage Page being edited
	 * @return bool
	 * @throws WireException
	 * 
	 */
	public static function isValidPage(Page $page, $field, Page $editPage = null) {
	
		if(!$field instanceof Field) $field = $page->wire('fields')->get($field);
		if(!$field instanceof Field) throw new WireException('isValidPage requires a valid Field or field name');
		
		if($editPage && $page->id == $editPage->id) {
			$editPage->setQuietly('_isValidPage', "Page is referencing itself and circular page reference not allowed");
			return false; // prevent circular reference
		}
		
		if($page->wire('pages')->cloning) {
			return true; // bypass check when cloning is active
		}

		$valid = true;
		$findPagesSelector = $field->get('findPagesSelector');
		if(empty($findPagesSelector)) $findPagesSelector = $field->get('findPagesSelect');
		
		if($findPagesSelector) { 
			$selector = $findPagesSelector; 
			if($editPage) $selector = self::getFindPagesSelector($editPage, $selector); 
			if(!$page->matches($selector)) {
				// failed in-memory check, attempt $page->count() check...
				$selector .= ", id=$page->id";
				if($page->wire('pages')->count($selector)) {
					// looks like its okay
				} else {
					// also fails $pages->cont() check, so definitely not valid
					if($editPage) $editPage->setQuietly('_isValidPage', "Page $page does not match findPagesSelector: $selector");
					$valid = false;
				}
			}
		} 
	
		// if($field->findPagesCode) { } // we don't currently validate these

		$parent_id = $field->get('parent_id');
		if($parent_id && $parent_id != $page->parent_id) {
			$inputfieldClass = ltrim($field->get('inputfield'), '_');
			if(empty($inputfieldClass)) $inputfieldClass = 'InputfieldSelect';
			if(version_compare(PHP_VERSION, '5.3.8') >= 0) {
				$interfaces = wireClassImplements($inputfieldClass);
				if(in_array('InputfieldPageListSelection', $interfaces)) {
					// parent_id represents a root parent
					$rootParent = $page->wire('pages')->get($parent_id); 
					if(!$page->parents()->has($rootParent)) $valid = false;
				} else {
					// parent_id represents a direct parent
					$valid = false;
				}
				if(!$valid && $editPage) {
					$editPage->setQuietly('_isValidPage', "Page $page does not have required parent $parent_id");
				}
			} else {
				// PHP version prior to 5.3.8
				// @deprecated
				$reflector = new \ReflectionClass($inputfieldClass); 
				$valid = $reflector->implementsInterface('InputfieldPageListSelection'); 
			}
		}
	
		$hasRequiredTemplate = true;
		$template_ids = FieldtypePage::getTemplateIDs($field);
		if(!empty($template_ids)) {
			$hasRequiredTemplate = in_array($page->template->id, $template_ids);
		}
		if(!$hasRequiredTemplate) { 
			$valid = false;
			if($editPage) {
				$editPage->setQuietly('_isValidPage', "Page $page does not have required template(s): " . implode(',', $template_ids));
			}
		}
		
		return $valid;
	}

	/**
	 * Execute the findPagesCode
	 * 
	 * @param Page $page The page being edited
	 * @return PageArray (hopefully)
	 * @deprecated Use hook to InputfieldPage::getSelectablePages() instead
	 * 
	 */
	protected function ___findPagesCode(Page $page) {
		if($page) {}
		$pages = $this->wire('pages'); // so that it is locally scoped to the eval
		if(empty($this->findPagesCode)) return $pages->newPageArray();
		return eval($this->findPagesCode);
	}

	public function has($key) {
		// ensures it accepts any config value (like those for delegate inputfields)
		return true; 
	}
	
	public function getSetting($key) {
		if($key === 'template_ids') return $this->getTemplateIDs();
		$value = parent::getSetting($key);
		if($key === 'template_id' && empty($value)) {
			$templateIDs = $this->getTemplateIDs();
			if(!empty($templateIDs)) $value = reset($templateIDs);
		}
		return $value;
	}

	/**
	 * Return PageArray of selectable pages for this input
	 * 
	 * @param Page $page The Page being edited
	 * @return PageArray|null
	 * 
	 */
	public function ___getSelectablePages(Page $page) {
		
		$lockedModes = array(Inputfield::collapsedNoLocked, Inputfield::collapsedYesLocked);
		$statusUnder = $this->allowUnpub ? Page::statusTrash : Page::statusUnpublished; 
		$children = null;
		$templateIDs = $this->getTemplateIDs(true);
		$findPagesSelector = $this->getSetting('findPagesSelector');
		if(empty($findPagesSelector)) $findPagesSelector = $this->getSetting('findPagesSelect');

		if($this->configMode) {
			$children = $this->wire('pages')->newPageArray();

		} else if($this->renderValueMode || in_array($this->getSetting('collapsed'), $lockedModes)) {
			$children = $this->attr('value');
			// convert to PageArray if not already
			if($children instanceof Page) {
				$children = $children->and(); 
			} else if(!$children instanceof PageArray) {
				$children = $this->wire('pages')->newPageArray();
			}
			
		} else if($findPagesSelector) { 
			// a find() selector
			$instance = $this->processInputMode ? $this : null;
			$selector = self::getFindPagesSelector($page, $findPagesSelector, $instance);
			$children = $this->pages->find($selector); 

		} else if($this->findPagesCode) {
			// php statement that returns a PageArray or a Page (to represent a parent)
			$children = $this->findPagesCode($page);
			if($children instanceof Page) $children = $children->children(); // @teppokoivula

		} else if($this->parent_id) {
			$parent = $this->wire('pages')->get($this->parent_id); 
			if($parent) {
				if($templateIDs) {
					$children = $parent->children("templates_id=$templateIDs, check_access=0, status<$statusUnder"); 
				} else {
					$children = $parent->children("check_access=0, status<$statusUnder");
				}
			}

		} else if($templateIDs) {
			$children = $this->pages->find("templates_id=$templateIDs, check_access=0, status<$statusUnder"); 

		} else {
			$children = $this->wire('pages')->newPageArray();
		}
	
		if($children && $children->has($page)) {
			$children->remove($page); // don't allow page being edited to be selected
		}

		return $children; 
	}

	/**
	 * Return array or string of configured template IDs
	 * 
	 * @param bool $getString Specify true to return a 1|2|3 style string rather than an array
	 * @return array|string
	 * 
	 */
	public function getTemplateIDs($getString = false) {
		$templateIDs = parent::getSetting('template_ids');
		$templateID = parent::getSetting('template_id');
		return FieldtypePage::getTemplateIDs(array($templateIDs, $templateID), $getString);
	}

	/**
	 * Populate any variables in findPagesSelector
	 * 
	 * @param Page $page
	 * @param string $selector
	 * @param Inputfield $inputfield
	 * @return string
	 *
	 */
	protected static function getFindPagesSelector(Page $page, $selector, $inputfield = null) {
	
		// if an $inputfield is passed in, then we want to retrieve dependent values directly
		// from the form, rather than from the $page
		/** @var InputfieldWrapper $form */
		if($inputfield) {
			// locate the $form
			$n = 0;
			$form = $inputfield;
			do {
				$form = $form->getParent();
				if(++$n > 10) break;
			} while($form && $form->className() != 'InputfieldForm'); 
		} else $form = null;

		// find variables identified by: page.field or page.field.subfield
		if(strpos($selector, '=page.') !== false) {
			preg_match_all('/=page\.([_.a-zA-Z0-9]+)/', $selector, $matches); 
			foreach($matches[0] as $key => $tag) {
				$field = $matches[1][$key];	
				$subfield = '';
				if(strpos($field, '.')) list($field, $subfield) = explode('.', $field); 
				$value = null;
				if($form && (!$subfield || $subfield == 'id')) {
					// attempt to get value from the form, to account for ajax changes that would not yet be reflected on the page
					$in = $form->getChildByName($field); 
					if($in) $value = $in->attr('value');
				}
				if(is_null($value)) $value = $page->get($field); 
				if(is_object($value) && $subfield) $value = $value->$subfield;
				if(is_array($value)) $value = implode('|', $value); 
				$selector = str_replace($tag, "=$value", $selector); 
			}
		}
		
		return $selector; 
	}

	/**
	 * Get a label for the given page
	 * 
	 * @param Page $page
	 * @param bool $allowMarkup Whether or not to allow markup in the label (default=false)
	 * @return string
	 * 
	 */
	public function getPageLabel(Page $page, $allowMarkup = false) {
		$label = '';
		if(strlen($this->labelFieldFormat) && $this->labelFieldName == '.') {
			$label = $page->getMarkup($this->labelFieldFormat);
		} else if($this->labelFieldName === '.') {
			// skip
		} else if($this->labelFieldName) {
			$label = $page->get($this->labelFieldName);
		}
		if(!strlen($label)) $label = $page->name;
		if($page->hasStatus(Page::statusUnpublished)) $label .= ' ' . $this->_('(unpublished)');
		if(!$allowMarkup) $label = $this->wire('sanitizer')->markupToLine($label);
		return $label;
	}

	/**
	 * Get the selected Inputfield class for input (adjuted version of $this->inputfield)
	 * 
	 * @return string
	 * 
	 */
	protected function getInputfieldClass() {
		return ltrim($this->getSetting('inputfield'), '_');
	}

	/**
	 * Get delegate Inputfield for page selection
	 * 
	 * @return Inputfield|null
	 * @throws WireException
	 * 
	 */
	public function getInputfield() {

		if($this->inputfieldWidget && ((string) $this->inputfieldWidget) == $this->getInputfieldClass()) {
			return $this->inputfieldWidget;
		}

		$inputfield = $this->wire('modules')->get($this->getInputfieldClass());
		if(!$inputfield) return null;
		if($this->derefAsPage) $inputfield->set('maxSelectedItems', 1); 

		$page = $this->page; 
		$process = $this->wire('process'); 
		if($process && $process instanceof WirePageEditor) $page = $process->getPage();

		$inputfield->attr('name', $this->attr('name')); 
		$inputfield->attr('id', $this->attr('id')); 
		$inputfield->label = $this->getSetting('label');
		$inputfield->description = $this->getSetting('description');
		
		$collapsed = $this->getSetting('collapsed');
		if($collapsed == Inputfield::collapsedYesAjax || 
			($collapsed == Inputfield::collapsedBlankAjax && $this->isEmpty())) {
			// quick exit when possible due to ajax field, and not being time to render or process it
			if($this->getParent()) {
				// limit only to inputfields that have a parent, to keep out of other form contexts like Lister
				$renderInputfieldAjax = $this->wire('input')->get('renderInputfieldAjax');
				$processInputfieldAjax = $this->wire('input')->post('processInputfieldAjax');
				if(!is_array($processInputfieldAjax)) $processInputfieldAjax = array();
				if($renderInputfieldAjax != $this->attr('id') && !in_array($this->attr('id'), $processInputfieldAjax)) {
					$this->inputfieldWidget = $inputfield;
					return $inputfield;
				}
			}
		}

		if(method_exists($inputfield, 'addOption')) {
			
			$children = $this->getSelectablePages($page);
			
			if($children) {
				foreach($children as $child) {
					$label = $this->getPageLabel($child);
					$inputfield->addOption($child->id, $label);
				}
			}
			
		} else {
			
			$parent_id = $this->getSetting('parent_id');
			$template_id = $this->getSetting('template_id');
			$template_ids = $this->getTemplateIDs();
			$findPagesCode = $this->getSetting('findPagesCode');
			$findPagesSelector = $this->getSetting('findPagesSelector');
			$labelFieldName = $this->getSetting('labelFieldName');
			$labelFieldFormat = $this->getSetting('labelFieldFormat');
			
			if(empty($findPagesSelector)) $findPagesSelector = $this->getSetting('findPagesSelect');
			
			if($parent_id) {
				$inputfield->parent_id = $parent_id;
			} else if($findPagesCode) {
				// @teppokoivula: use findPagesCode to return single parent page
				$child = $this->findPagesCode($page);
				if($child instanceof Page) $inputfield->parent_id = $child->id; 
			}
			
			if($template_id) $inputfield->template_id = $template_id; 
			if(!empty($template_ids)) $inputfield->template_ids = $template_ids;
			
			if($findPagesSelector) {
				$inputfield->findPagesSelector = self::getFindPagesSelector($page, $findPagesSelector); 
			}
			
			if(strlen($labelFieldFormat) && $labelFieldName === '.') {
				$inputfield->labelFieldName = $labelFieldFormat;
				$inputfield->labelFieldFormat = $labelFieldFormat;
			} else {
				$inputfield->labelFieldName = $labelFieldName == '.' ? 'name' : $labelFieldName;
				$inputfield->labelFieldFormat = '';
			}				
		}

		$value = $this->attr('value'); 
		if($value instanceof Page) {
			$inputfield->attr('value', $value->id); // derefAsPage
		} else if($value instanceof PageArray) {
			foreach($value as $v) {
				$inputfield->attr('value', $v->id); // derefAsPageArray
			}
		}

		// pass long any relevant configuration items
		foreach($this->data as $key => $value) {
			if(in_array($key, array('value', 'collapsed')) || array_key_exists($key, self::$defaultConfig)) continue; 
			if($key == 'required' && empty($this->data['defaultValue'])) continue; // for default value support with InputfieldSelect
			$inputfield->set($key, $value); 
		}
		
		$inputfield->set('allowUnpub', $this->getSetting('allowUnpub'));

		$this->inputfieldWidget = $inputfield;
		
		return $inputfield; 
	}

	/**
	 * Called before render()
	 * 
	 * @param Inputfield $parent
	 * @param bool $renderValueMode
	 * @return bool
	 * 
	 */
	public function renderReady(Inputfield $parent = null, $renderValueMode = false) {
	
		$this->renderValueMode = $renderValueMode;
		parent::renderReady($parent, $renderValueMode);
		$inputfield = $this->getInputfield();
		
		if(!$inputfield) {
			$this->error($this->_('This field needs to be configured before it can be used.'));
			return false;
		}
		
		$this->addClass('InputfieldNoFocus', 'wrapClass');
		
		return $inputfield->renderReady($this, $renderValueMode);
	}

	/**
	 * Render
	 * 
	 * @return string
	 * @throws WireException
	 * 
	 */
	public function ___render() {

		$inputfield = $this->getInputfield();
		if(!$inputfield) return $this->attr('name');
		
		$classes = InputfieldWrapper::getClasses();
		$class = $inputfield->className();
		if(isset($classes[$class]['item_content'])) $class .= " " . $classes[$class]['item_content'];
		
		foreach($this->classesAdded as $addClass) {
			$inputfield->addClass($addClass);
		}

		$out = 	"<div class='$class'>";
		$out .= $inputfield->render();
		$out .= $this->renderAddable();

		$findPagesSelector = $this->getSetting('findPagesSelector');
		if(empty($findPagesSelector)) $findPagesSelector = $this->getSetting('findPagesSelect');
		$labelFieldFormat = $this->getSetting('labelFieldFormat');
		$labelFieldName = $this->getSetting('labelFieldName');
		
		if($findPagesSelector) {
			$selector = $this->wire('sanitizer')->entities($findPagesSelector); 
			$formatName = '';
			if($this->wire('user')->hasPermission('page-edit') && strlen($labelFieldFormat) && $labelFieldName === '.') {
				/** @var ProcessPageSearch $pps */
				$formatName = "page_" . $this->attr('name');
				try {
					/** @var ProcessPageSearch $pps */
					$pps = $this->wire('modules')->get('ProcessPageSearch');
					$pps->setDisplayFormat($formatName, $labelFieldFormat);
				} catch(\Exception $e) {
					// most likely user does not have access to ProcessPageSearch
				}
			}
			$labelFieldName = $labelFieldName == '.' ? 'name' : $labelFieldName;	
			$out .= "<input " . 
				"type='hidden' " . 
				"class='findPagesSelector' " . 
				"data-formatname='$formatName' " . 
				"data-label='$labelFieldName' " . 
				"value='$selector' />";
		}
		
		$out .= "</div>";

		return $out; 
	}

	/**
	 * Render the add page(s) section
	 * 
	 * @return string
	 * @throws WireException
	 * 
	 */
	protected function ___renderAddable() {
		
		$parent_id = $this->getSetting('parent_id');
		$template_id = $this->getSetting('template_id');
		$labelFieldName = $this->getSetting('labelFieldName');

		if(!$this->getSetting('addable') || !$parent_id || !$template_id) return '';

		if($labelFieldName && $labelFieldName != 'title') return '';

		$parent = $this->wire('pages')->get($parent_id); 

		$test = $this->wire('pages')->newPage(array(
			'template' => $this->wire('templates')->get($template_id)
		));
		$test->parent = $parent; 
		$test->id = -1; // prevents permissions check from failing

		if(!$parent->addable($test)) return ''; 
		if(!$test->publishable()) return '';

		$inputfield = $this->wire('modules')->get($this->getInputfieldClass()); 
		if(!$inputfield) return '';
		$key = "_{$this->name}_add_items";

		if($inputfield instanceof InputfieldHasArrayValue) {
			// multi value
			$description = $this->_('Enter the titles of the items you want to add, one per line. They will be created and added to your selection when you save the page.');
			$input = "<textarea id='$key' name='$key' rows='5'></textarea>";
		} else {
			// single value
			$description = $this->_('Enter the title of the item you want to add. It will become selected when you save the page.');
			$input = "<input type='text' name='$key' id='$key' />";
		}

		$notes = sprintf($this->_('New pages will be added to %s'), $parent->path);
		$label ="<i class='fa fa-plus-circle'></i> " . $this->_('Create New'); 

		$out = 	
			"<div class='InputfieldPageAdd'>" . 	
			"<p class='InputfieldPageAddButton'><a href='#'>$label</a></p>" . 
			"<p class='InputfieldPageAddItems'>" . 
			"<label class='description' for='$key'>$description</label>" . 
			"$input" . 
			"<span class='detail'>$notes</span>" . 
			"</p>" . 
			"</div>";

		return $out; 
	}

	public function ___renderValue() {

		if($this->labelFieldName == '.') {
			$labelFieldFormat = $this->labelFieldFormat;
			$labelFieldName = 'title|name';
		} else {
			$labelFieldFormat = '';
			$labelFieldName = $this->labelFieldName ? $this->labelFieldName : 'title';
			$labelFieldName .= "|name";
		}
		
		$value = $this->attr('value');

		if(is_array($value) || $value instanceof PageArray) { 
			$out = '<ul class="PageArray pw-bullets">';
			foreach($value as $p) {
				$of = $p->of();
				$p->of(true);
				$v = $labelFieldFormat ? $p->getText($labelFieldFormat, true, true) : $p->get($labelFieldName);
				if(!strlen($v)) $v = $p->get('name');
				$out .= "<li>$v</li>";
				$p->of($of);
			}
			$out .= "</ul>";

		} else if($value instanceof Page) {
			$of = $value->of();
			$value->of(true);
			$out = $labelFieldFormat ? $value->getText($labelFieldFormat, true, true) : $value->get($labelFieldName);
			if(!strlen($out)) $out = $value->get('name');
			$value->of($of);

		} else {
			$out = $value; 
		}

		return $out; 
	}

	public function ___processInput(WireInputData $input) {

		$this->processInputMode = true; 
		$inputfield = $this->getInputfield();
		if(!$inputfield) return $this;
		$inputfield->processInput($input); 

		$value = $this->attr('value'); 
		$existingValueStr = $value ? "$value" : '';
		$newValue = null;
		$value = $inputfield->attr('value');
		
		if(is_array($value)) {
			$newValue = $this->wire('pages')->newPageArray(); 
			foreach($value as $v) {
				$id = (int) $v; 
				if(!$id) continue; 
				if($id > 0) {	
					// existing page
					$page = $this->wire('pages')->get($id); 
					if($page->hasStatus(Page::statusUnpublished) && !$this->getSetting('allowUnpub')) {
						// disallow unpublished
						$warning = sprintf($this->_('Unpublished page %1$s is not allowed in field "%2$s"'), $page->path, $this->label);
						if($this->wire('user')->isSuperuser()) {
							$warning .= ' ' . sprintf($this->_('To allow unpublished pages, edit the "%s" field and see the setting on the "Advanced" tab.'), $this->name);
						}
						$this->warning($warning);
						continue; 
					}
				} else {
					// placeholder for new page, to be sorted later
					$page = $this->wire('pages')->newNullPage(); 
				}
				$newValue->add($page); 
			}

		} else if($value) {
			$newValue = $this->wire('pages')->get((int) $value); 
			if($newValue->hasStatus(Page::statusUnpublished) && !$this->getSetting('allowUnpub')) $newValue = null; // disallow unpublished
		}

		$this->setAttribute('value', $newValue); 
		$this->processInputAddPages($input);

		// if pages were added, re-sort them in case they were dragged to a different order
		// an example of this would be when used with the InputfieldPageAutocomplete
		if(count($this->pagesAdded) && is_array($value)) {
			$sortedValue = $this->wire('pages')->newPageArray();
			foreach($newValue as $page) {
				if($page->id < 1) $page = $this->pagesAdded->shift();
				if($page->id && !$sortedValue->has($page)) $sortedValue->add($page);
			}
			$newValue = $sortedValue;
			$this->setAttribute('value', $newValue); 
		}

		if("$newValue" != "$existingValueStr") {
			$this->trackChange('value'); 
		} 
		
		$this->processInputMode = false; 	
		
		return $this; 
	}

	/**
	 * Check for the addable pages option and process if applicable
	 * 
	 * @param WireInputData $input
	 *
	 */
	protected function ___processInputAddPages($input) {

		$this->pagesAdded = $this->wire('pages')->newPageArray();
		$parent_id = $this->getSetting('parent_id');
		$template_id = $this->getSetting('template_id');

		if(!$this->getSetting('addable') || !$parent_id || !$template_id) return;

		$user = $this->wire('user'); 
		$key = "_{$this->name}_add_items";
		$value = trim($input->$key); 
		
		if(empty($value)) return;

		$parent = $this->pages->get($parent_id);
		$sort = $parent->numChildren;
		$titles = explode("\n", $value);
		$n = 0;

		foreach($titles as $title) {

			// check if there is an existing page using this title
			$selector = "include=all, templates_id=$template_id, title=" . $this->wire('sanitizer')->selectorValue($title); 
			$existingPage = $parent->child($selector);
			if($existingPage->id) {
				// use existing page
				$this->pagesAdded->add($existingPage);
				if($this->value instanceof PageArray) {
					$this->value->add($existingPage); 
					continue; 
				} else {
					$this->value = $existingPage; 
					break;
				}
			}

			// create a new page
			$page = $this->wire('pages')->newPage();
			$page->template = $template_id; 
			$page->parent = $parent; 
			$page->title = trim($title); 
			$page->sort = $sort++;
			$page->id = -1; // prevents the permissions check from failing

			// on first iteration perform a page-context access check
			if(!$n && (!$parent->addable($page) || !$page->publishable())) {
				$this->error("No access to add {$page->template} pages to {$parent->path}"); 
				break;
			}
			$page->id = 0;

			try {
				$page->save();
				$this->message(sprintf($this->_('Added page %s'), $page->path)); 
				if($this->value instanceof PageArray) $this->value->add($page); 
					else $this->value = $page; 
				$this->pagesAdded->add($page);
				$this->trackChange('value'); 
				$n++;

			} catch(\Exception $e) {
				$error = sprintf($this->_('Error adding page "%s"'), $page->title);
				if($user->isSuperuser()) $error .= " - " . $e->getMessage(); 
				$this->error($error); 
				break;
			}

			if($this->value instanceof Page) break;
		}
	}

	/**
	 * Does this Inputfield have an empty value?
	 * 
	 * @return bool
	 * 
	 */
	public function isEmpty() {
		$value = $this->attr('value'); 

		if($value instanceof Page) {
			// derefAsPage
			return $value->id < 1; 

		} else if($value instanceof PageArray) {
			// derefAsPageArray
			/** @var PageArray $value */
			if(!count($value)) return true; 

		} else {
			// null
			return true; 
		}

		return false; 
	}

	/**
	 * Get field configuration Inputfields
	 * 
	 * @return InputfieldWrapper
	 * @throws WireException
	 * 
	 */
	public function ___getConfigInputfields() {
		// let the module know it's being used for configuration purposes
		$this->configMode = true; 
		$exampleLabel = $this->_('Example:') . ' ';
		$defaultLabel = ' ' . $this->_('(default)'); 

		$inputfields = new InputfieldWrapper();
		$this->wire($inputfields);

		$fieldset = $this->wire('modules')->get('InputfieldFieldset'); 
		$fieldset->label = $this->_('Selectable pages');
		$fieldset->attr('name', '_selectable_pages'); 
		$fieldset->description = $this->_('Use at least one of the options below to determine which pages will be selectable with this field.');
		$fieldset->icon = 'files-o';
		$selectablePagesFieldset = $fieldset;
		
		/** @var InputfieldPageListSelect $field */
		$field = $this->modules->get('InputfieldPageListSelect');
		$field->setAttribute('name', 'parent_id'); 
		$field->label = $this->_('Parent');
		$field->attr('value', (int) $this->parent_id); 
		$field->description = $this->_('Select the parent of the pages that are selectable.');
		$field->required = false;
		$field->icon = 'folder-open-o';
		$field->collapsed = Inputfield::collapsedBlank;
		$fieldset->append($field);

		/** @var InputfieldSelect $field */
		$field = $this->modules->get('InputfieldSelect');
		$field->setAttribute('name', 'template_id');
		$field->label = $this->_('Template');
		$field->description = $this->_('Select the template of the pages that are selectable. May be used instead of, or in addition to, the parent above.'); // Description for Template of selectable pages
		foreach($this->templates as $template) {
			$field->addOption($template->id, $template->name);
		}
		$template_id = $this->getSetting('template_id');
		$field->attr('value', $template_id);
		$field->collapsed = Inputfield::collapsedBlank;
		$field->icon = 'cube';
		$fieldset->append($field);
		
		$templateIDs = $this->getTemplateIDs();
		$key = array_search($template_id, $templateIDs);
		if(is_int($key)) unset($templateIDs[$key]);
		/** @var InputfieldAsmSelect $field */
		$field = $this->modules->get('InputfieldAsmSelect');
		$field->attr('name', 'template_ids');
		$field->label = $this->_('Additional templates');
		$field->description = $this->_('If you need additional templates for selectable pages, select them here.');
		// $field->description .= ' ' . $this->_('This may not be supported by all input types.');
		$field->icon = 'cubes';
		foreach($this->templates as $template) {
			$field->addOption($template->id, $template->name);
		}
		$field->attr('value', $templateIDs);
		$field->collapsed = Inputfield::collapsedBlank;
		$field->showIf = 'template_id!=0';
		if(count($templateIDs) == 1 && reset($templateIDs) == $this->getSetting('template_id')) {
			$field->collapsed = Inputfield::collapsedYes;
		}
		$fieldset->append($field);

		$extra = $this->_('While this overrides parent and template selections above, those selections (if present) are still used for validation.'); // Additional notes

		/** @var InputfieldSelector $field */
		$field = $this->modules->get('InputfieldSelector');
		$field->description = $this->_('Add one or more fields below to create a query that finds the pages you want to make selectable.');
		$field->description .= ' ' . $this->_('This creates a selector that finds pages at runtime. If you prefer to enter this manually, use the “Selector string” option below instead.');
		$field->description .= ' ' . $extra;
		$field->attr('name', 'findPagesSelect');
		$field->label = $this->_('Custom find');
		$field->attr('value', $this->get('findPagesSelect'));
		//$field->collapsed = Inputfield::collapsedBlank;
		$field->icon = 'search-plus';
		$field->addLabel = $this->_('Add field to query');
		$field->allowSystemCustomFields = true;
		$field->allowSystemTemplates = true;
		$field->showFieldLabels = 1;
		$field->collapsed = Inputfield::collapsedBlank;
		$fieldset->append($field);


		/** @var InputfieldText $field */
		$field = $this->modules->get('InputfieldText'); 
		$field->attr('name', 'findPagesSelector'); 
		$field->label = $this->_('Selector string'); 
		$field->attr('value', $this->findPagesSelector); 
		$field->description = $this->_('If you want to find selectable pages using a ProcessWire selector, enter the selector string to find the selectable pages. This selector will be passed to a `$pages->find("your selector");` call.'); // Description for Custom selector to find selectable pages
		$field->description .= ' ' . $extra;
		$field->notes = $exampleLabel . $this->_('parent=/products/, template=product, sort=name'); // Example of Custom selector to find selectable pages
		$field->collapsed = Inputfield::collapsedBlank;
		$field->icon = 'search';
		$fieldset->append($field);

		if($this->findPagesCode) {
			// allow only if already present, as this option is deprecated
			/** @var InputfieldTextarea $field */
			$field = $this->modules->get('InputfieldTextarea');
			$field->attr('name', 'findPagesCode');
			$field->attr('value', $this->findPagesCode);
			$field->attr('rows', 4);
			$field->description = $this->_('If you want to find selectable pages using a PHP code snippet rather than selecting a parent page or template (above) then enter the code to find the selectable pages. This statement has access to the $page and $pages API variables, where $page refers to the page being edited.'); // Description for Custom PHP to find selectable pages 1
			$field->description .= ' ' . $this->_('The snippet should return either a PageArray, Page or NULL. If it returns a Page, children of that Page are used as selectable pages. Using this is optional, and if used, it overrides the parent/template/selector fields above.'); // Description for Custom PHP to find selectable pages 2
			$field->description .= ' ' . $extra;
			$field->description .= ' ' . $this->_('NOTE: Not compatible with PageListSelect or Autocomplete input field types.'); // Description for Custom PHP to find selectable pages 3
			$field->notes = $exampleLabel . $this->_('return $page->parent->parent->children("name=locations")->first()->children();'); // Example of Custom PHP code to find selectable pages
			$field->collapsed = Inputfield::collapsedBlank;
		} else {
			$field = $this->modules->get('InputfieldMarkup');
			$field->attr('name', '_findPagesCode');
			$field->collapsed = Inputfield::collapsedYes;
			$if = "\$event-&gt;object-&gt;" . 
				($this->name ? "hasField == '<strong>$this->name</strong>'" : "name == '<strong>your_field_name</strong>'");
			$field->value = '<p>' . 
				sprintf($this->_('Add the following hook to a %s file and modify per your needs. The hook should find and return selectable pages in a PageArray.'), '<u>/site/ready.php</u>') . 
				"</p><pre><code>" . 
				"\$wire-&gt;addHookAfter('InputfieldPage::getSelectablePages', function(\$event) {" .
				"\n  if($if) {" . 
				"\n    \$event->return = \$event-&gt;pages-&gt;find('<strong>your selector here</strong>');" . 
				"\n  }" . 
				"\n});" . 
				"</code></pre>" . 
				"<p>" . 
				sprintf($this->_('If you need to know the page being edited, it is accessible from: %s'), 
					"<code>\$event-&gt;arguments('page');</code>") . 
				"</p>";
		}
		$field->label = $this->_('Custom PHP code');
		$field->icon = 'code';
		$field->showIf = 'inputfield!=InputfieldPageAutocomplete|InputfieldPageListSelect|InputfieldPageListSelectMultiple';
		$fieldset->append($field);

		$inputfields->append($fieldset); 

		/** @var InputfieldSelect $field */
		$field = $this->modules->get('InputfieldSelect');
		$field->attr('name', 'labelFieldName');
		$field->label = $this->_('Label field');
		$field->required = true; 
		$field->icon = 'thumb-tack';
		$field->description = $this->_('Select the page field that you want to be used in generating the labels for each selectable page.'); // Description for Label Field
		$field->notes = $this->_('Select "Custom format" if you want to specify multiple fields, or other fields you do not see above.');
		$field->addOption('.', $this->_('Custom format (multiple fields)' . ' ...'));
		$field->columnWidth = 50;
		
		if($this->wire('fields')->get('title')) {
			$field->addOption('title', 'title' . $defaultLabel);
			$field->addOption('name', 'name');
			$titleIsDefault = true;
		} else {
			$field->addOption('name', 'name' . $defaultLabel);
			$titleIsDefault = false;
		}
		$field->addOption('path', 'path'); 

		foreach($this->wire('fields') as $f) {
			if(!$f->type instanceof FieldtypeText) continue;
			if($f->type instanceof FieldtypeTextarea) continue; 
			if($titleIsDefault && $f->name == 'title') continue;
			$field->addOption($f->name);
		}
		if(!$this->labelFieldFormat) {
			if($this->labelFieldName === '.') {
				// they want a custom format, but they didn't provide one
				$this->labelFieldName = $titleIsDefault ? 'title' : 'name';
			}
		}
		if(!$this->labelFieldName) {
			// no label field name means we fall back to default
			$this->labelFieldName = $titleIsDefault ? 'title' : 'name';
		}
		$field->attr('value', $this->labelFieldName);
		$inputfields->append($field); 
	
		/** @var InputfieldText $field */
		$field = $this->modules->get('InputfieldText');
		$field->attr('name', 'labelFieldFormat');
		$field->attr('value', $this->labelFieldFormat);
		$field->label = $this->_('Custom page label format');
		$field->description = $this->_('Specify one or more field names surrounded by curly {brackets} along with any additional characters, spacing or punctuation.'); // Description for custom page label format
		$field->notes = $this->_('Example: {parent.title} - {title}, {date}'); 
		$field->columnWidth = 50;
		$field->showIf = 'labelFieldName=.';
		$field->required = true;
		$field->requiredIf = 'labelFieldName=.';
		$inputfields->add($field);

		if(!$this->inputfield) $this->inputfield = 'InputfieldSelect';
		
		/** @var InputfieldSelect $field */
		$field = $this->modules->get('InputfieldSelect');
		$field->setAttribute('name', 'inputfield'); 
		$field->setAttribute('value', $this->inputfield); 
		$field->label = $this->_('Input field type');
		$field->description = $this->_('The type of input field (Inputfield module) that will be used to select page(s) for this field.');
		$field->description .= ' ' . $this->_('Select one that is consistent with your “Value type” selection on the “Details” tab for single or multiple-page selection.'); 
		$field->notes = $this->_('After selecting an input field type and saving changes, please note that additional configuration options specific to your selection may appear directly below this.'); 
		$field->required = true; 
		$field->icon = 'plug';
		$inputfieldSelection = $field;
		
		$singles = array();
		$multiples = array();
		$sortables = array();
		$pageListTypes = array();

		foreach($this->inputfieldClasses as $class) {
			$module = $this->modules->getModule($class, array('noInit' => true)); 
			$info = $this->modules->getModuleInfo($module);
			$label = ucfirst($info['title']);
			if($module instanceof InputfieldPageListSelection) {
				$pageListTypes[] = $class;
			}
			if($module instanceof InputfieldHasSortableValue) {
				$sortables[$class] = $label;
			} else if($module instanceof InputfieldHasArrayValue) {
				$multiples[$class] = $label;
			} else {
				$singles[$class] = $label;
			}
			if($class == 'InputfieldPageAutocomplete') $singles["_$class"] = $label;
		}

		$multiLabel = $this->_('Multiple page selection');
		$field->addOption($this->_('Single page selection'), $singles);
		$field->addOption($multiLabel, $multiples);
		$field->addOption($multiLabel . ' (' . $this->_('sortable') . ')', $sortables); 
		$inputfields->insertBefore($field, $selectablePagesFieldset); 	
	
		if($this->hasFieldtype !== false) {
			
			$f = $this->modules->get('InputfieldMarkup');
			$f->label = $this->_('Regarding “Page List” input types');
			$f->icon = 'warning';
			$f->showIf = 'inputfield=' . implode('|', $pageListTypes);
			$f->value = '<p>' .
				$this->_('You have selected an input type that has specific requirements.') . ' ' .
				$this->_('Specify only the “Parent” option below when configuring “Selectable pages”.') . ' ' .
				$this->_('Note that the parent you specify implies the root of the tree of selectable pages.') . ' ' . 
				$this->_('If you want to make everything selectable, then specify nothing.') .
				'</p>';
			$inputfields->insertAfter($f, $field);
			
			$field = $this->modules->get('InputfieldCheckbox');
			$field->attr('name', 'addable');
			$field->attr('value', 1);
			$field->icon = 'lightbulb-o';
			$field->label = $this->_('Allow new pages to be created from field?');
			$field->description = $this->_('If checked, an option to add new page(s) will also be present if the indicated requirements are met.');
			$field->notes =
				$this->_('1. Both a parent and template must be specified in the “Selectable pages” section above.') . "\n" .
				$this->_('2. The editing user must have access to create/publish these pages.') . "\n" .
				$this->_('3. The “label field” must be set to “title (default)”.');

			if($this->addable) {
				$field->attr('checked', 'checked');
			} else {
				$field->collapsed = Inputfield::collapsedYes;
			}
			$inputfields->append($field);
		}
		
		foreach(parent::___getConfigInputfields() as $inputfield) {
			$inputfields->add($inputfield);
		}

		$inputfield = $this->getInputfield();
		if($inputfield) {
			// tell it it's under control of a parent, regardless of whether this one is hasFieldtype true or not.
			$info = $this->modules->getModuleInfo($inputfield);
			$inputfield->hasFieldtype = true; 
			/** @var InputfieldFieldset $fieldset */
			$fieldset = $this->modules->get('InputfieldFieldset');
			$n = 0;
			foreach($inputfield->___getConfigInputfields() as $f) {
				if(in_array($f->name, array('required', 'requiredIf', 'showIf', 'collapsed', 'columnWidth'))) continue;
				if(array_key_exists($f->name, self::$defaultConfig)) continue;
				// if we already have the given field, skip over it to avoid duplication
				if($f->name && $inputfields->getChildByName($f->name)) continue; 
				$fieldset->add($f); 
				$n++;
			}
			if($n) {
				$fieldset->label = sprintf($this->_('Settings specific to “%s”'), $info['title']);
				$fieldset->icon = 'gear';
				$fieldset->collapsed = Inputfield::collapsedYes;
				$inClass = $inputfield->className();
				$fieldset->showIf = 'inputfield=' . $inClass;
				if($inClass == 'InputfieldPageAutocomplete') $fieldset->showIf .= "|_$inClass";
				$inputfields->insertAfter($fieldset, $inputfieldSelection);
			}
		}
		
		$this->configMode = false; // reverse what was set at the top of this function
		return $inputfields; 
	}

	/**
	 * Get module configuration Inputfields
	 * 
	 * @param array $data
	 * @return InputfieldWrapper
	 * 
	 */
	public function getModuleConfigInputfields(array $data) {

		$name = 'inputfieldClasses';

		if(!isset($data[$name]) || !is_array($data[$name])) $data[$name] = self::$defaultInputfieldClasses; 
		$fields = $this->wire(new InputfieldWrapper());
		$modules = $this->wire('modules');
		/** @var InputfieldAsmSelect $field */
		$field = $modules->get("InputfieldAsmSelect");
		$field->attr('name', $name);
		foreach($modules->find('className^=Inputfield') as $inputfield) {
			$field->addOption($inputfield->className(), str_replace('Inputfield', '', $inputfield->className())); 
		}
		$field->attr('value', $data[$name]); 
		$field->label = $this->_('Inputfield modules available for page selection');
		$field->description = $this->_('Select the Inputfield modules that may be used for page selection. These should generally be Inputfields that allow you to select one or more options.'); // Description 
		$fields->append($field);

		return $fields;
	}



	
}
