<?php

/**
 * Provides a tagging interface, storing comma-delimited tags in a DataObject string field.
 *
 * This is intended bridge the gap between 1.x and 2.x, and when possible TagField should be used
 * instead.
 *
 * @package forms
 * @subpackage fields
 */
class StringTagField extends DropdownField {
	/**
	 * @var array
	 */
	public static $allowed_actions = array(
		'suggest',
	);

	/**
	 * @var bool
	 */
	protected $shouldLazyLoad = false;

	/**
	 * @var int
	 */
	protected $lazyLoadItemLimit = 10;

	/**
	 * @var null|DataObject
	 */
	protected $record;

	/**
	 * @param string $name
	 * @param string $title
	 * @param array|SS_List $source
	 * @param array|SS_List $value
	 */
	public function __construct($name, $title = '', $source = array(), $value = array()) {
		parent::__construct($name, $title, $source, $value);
	}

	/**
	 * @return bool
	 */
	public function getShouldLazyLoad() {
		return $this->shouldLazyLoad;
	}

	/**
	 * @param bool $shouldLazyLoad
	 *
	 * @return static
	 */
	public function setShouldLazyLoad($shouldLazyLoad) {
		$this->shouldLazyLoad = $shouldLazyLoad;

		return $this;
	}

	/**
	 * @return int
	 */
	public function getLazyLoadItemLimit() {
		return $this->lazyLoadItemLimit;
	}

	/**
	 * @param int $lazyLoadItemLimit
	 *
	 * @return static
	 */
	public function setLazyLoadItemLimit($lazyLoadItemLimit) {
		$this->lazyLoadItemLimit = $lazyLoadItemLimit;

		return $this;
	}

	/**
	 * @return null|DataObject
	 */
	public function getRecord() {
		if($this->record) {
			return $this->record;
		}

		if($form = $this->getForm()) {
			return $form->getRecord();
		}

		return null;
	}

	/**
	 * @param DataObject $record
	 *
	 * @return $this
	 */
	public function setRecord(DataObject $record) {
		$this->record = $record;

		return $this;
	}

	/**
	 * {@inheritdoc}
	 */
	public function Field($properties = array()) {
		Requirements::css(TAG_FIELD_DIR . '/css/select2.min.css');
		Requirements::css(TAG_FIELD_DIR . '/css/TagField.css');

		Requirements::javascript(THIRDPARTY_DIR . '/jquery/jquery.js');
		Requirements::javascript(THIRDPARTY_DIR . '/jquery-entwine/dist/jquery.entwine-dist.js');
		Requirements::javascript(TAG_FIELD_DIR . '/js/select2.js');
		Requirements::javascript(TAG_FIELD_DIR . '/js/TagField.js');

		$this->addExtraClass('ss-tag-field');

		$this->setAttribute('multiple', 'multiple');

		if($this->getShouldLazyLoad()) {
			$this->setAttribute('data-ss-tag-field-suggest-url', $this->getSuggestURL());
		} else {
			$properties = array_merge($properties, array(
				'Options' => $this->getOptions()
			));
		}

		return $this
			->customise($properties)
			->renderWith(array("templates/TagField"));
	}

	/**
	 * @return string
	 */
	protected function getSuggestURL() {
		return Controller::join_links($this->Link(), 'suggest');
	}

	/**
	 * @return ArrayList
	 */
	protected function getOptions() {
		$options = ArrayList::create();

		$source = $this->getSource();

		if($source instanceof Iterator) {
			$source = iterator_to_array($source);
		}

		$values = $this->Value();

		foreach($source as $value) {
			$options->push(
				ArrayData::create(array(
					'Title' => $value,
					'Value' => $value,
					'Selected' => in_array($value, $values),
				))
			);
		}

		return $options;
	}

	/**
	 * {@inheritdoc}
	 */
	public function setValue($value, $source = null) {
		if(is_string($value)) {
			$value = explode(',', $value);
		}

		if($source instanceof DataObject) {
			$name = $this->getName();
			$value = explode(',', $source->$name);
		}

		if($source instanceof SS_List) {
			$value = $source->column('ID');
		}

		return parent::setValue(array_filter($value));
	}

	/**
	 * {@inheritdoc}
	 */
	public function getAttributes() {
		return array_merge(
			parent::getAttributes(),
			array('name' => $this->getName() . '[]')
		);
	}

	/**
	 * {@inheritdoc}
	 */
	public function saveInto(DataObjectInterface $record) {
		parent::saveInto($record);

		$name = $this->getName();

		$record->$name = join(',', $this->Value());
		$record->write();
	}

	/**
	 * Returns a JSON string of tags, for lazy loading.
	 *
	 * @param SS_HTTPRequest $request
	 *
	 * @return SS_HTTPResponse
	 */
	public function suggest(SS_HTTPRequest $request) {
		$responseBody = Convert::raw2json(
			array('items' => array())
		);

		$response = new SS_HTTPResponse();
		$response->addHeader('Content-Type', 'application/json');

		if($record = $this->getRecord()) {
			$tags = array();
			$term = $request->getVar('term');

			if($record->hasField($this->getName())) {
				$tags = $this->getTags($term);
			}

			$responseBody = Convert::raw2json(
				array('items' => $tags)
			);
		}

		$response->setBody($responseBody);

		return $response;
	}

	/**
	 * Returns array of arrays representing tags.
	 *
	 * @param string $term
	 *
	 * @return array
	 */
	protected function getTags($term) {
		$record = $this->getRecord();

		if(!$record) {
			return array();
		}

		$fieldName = $this->getName();
		$className = $record->getClassName();

		$term = Convert::raw2sql($term);

		$query = $className::get()
			->filter($fieldName . ':PartialMatch:nocase', $term)
			->limit($this->getLazyLoadItemLimit());

		$items = array();

		foreach($query->column($fieldName) as $tags) {
			$tags = explode(',', $tags);

			foreach($tags as $i => $tag) {
				if(stripos($tag, $term) !== false && !in_array($tag, $items)) {
					$items[] = array(
						'id' => $tag,
						'text' => $tag
					);
				}
			}
		}

		return $items;
	}
	
	/**
	 * DropdownField assumes value will be a scalar so we must
	 * override validate. This only applies to Silverstripe 3.2+
	 *
	 * @param Validator $validator
	 * @return bool
	 */
	public function validate($validator) {
		return true;
	}

}