pulsarvp/vps-tools

<?php
    namespace vps\tools\components;

    use Yii;

    /**
     * This class is intended to manage category tree which is in turn based on
     * nested sets behavior. Yii2 nested set behavior is used - https://github.com/creocoder/yii2-nested-set
     *
     * @author        Anna Manaenkova <anna.manaenkova@phystech.edu>
     * @package       vps\tools\components
     *
     * @property  array   $all
     * @property Category $root
     * @property  string  $modelClass
     */
    class CategoryManager extends \yii\base\BaseObject
    {
        /**
         * @var Category[] Category tree.
         */
        protected $_data = [];

        /**
         * @var string This is for imploding GUIDs in guid paths.
         */
        protected $_guidPathDelimiter = ':';

        /**
         * @var string
         */
        protected $_modelClass = '\common\models\Category';

        /**
         * @var Category Root category.
         */
        protected $_root;

        /**
         * @var string This is for imploding titles in title paths.
         */
        protected $_titlePathDelimiter = ' : ';

        /**
         * Populates category tree with data loaded from database.
         * @inheritdoc
         */
        public function init ()
        {
            $class = $this->_modelClass;

            $this->_root = $class::find()->roots()->one();
            if ($this->_root == null)
            {
                $root = new $class([ 'guid' => 'root', 'title' => 'ROOT' ]);
                $root->makeRoot();

                $this->_root = $class::find()->roots()->one();
                $this->_data = [];
            }
            else
                $this->_data = $this->_root->children()->all();

            $this->buildPaths();
        }

        /**
         * @property-read Category[] $all
         * @return Category[]
         */
        public function getAll ()
        {
            return $this->_data;
        }

        /**
         * Gets children of current category.
         * @param Category $category
         * @return array
         */
        public function getChildren ($category)
        {
            $children = [];
            foreach ($this->_data as $item)
                if ($item->lft > $category->lft and $item->rgt < $category->rgt)
                    $children[] = $item;

            return $children;
        }

        /**
         * Finds category parent with given depth.
         * @param  Category $category
         * @param int       $depth
         * @return Category|null
         */
        public function getParent ($category, $depth = 1)
        {
            if ($category instanceof $this->_modelClass and $depth > 0)
            {
                if ($category->depth == $depth)
                    return $category;
                foreach ($this->_data as $item)
                    if ($category->lft > $item->lft and $category->rgt < $item->rgt and $item->depth == $depth)
                        return $item;
            }

            return null;
        }

        /**
         * Finds all parents from top one to nearest.
         * @param  Category $category
         * @return Category[]|null
         */
        public function getParents ($category)
        {
            if ($category instanceof $this->_modelClass)
            {
                $parents = [];
                foreach ($this->_data as $item)
                    if ($category->lft > $item->lft and $category->rgt < $item->rgt)
                        $parents[] = $item;

                return $parents;
            }

            return null;
        }

        /**
         * @property-read Category $root
         * @return Category
         */
        public function getRoot ()
        {
            return $this->_root;
        }

        /**
         * Gets single category by its ID.
         * @param integer $id
         * @return Category|null
         */
        public function get ($id)
        {
            foreach ($this->_data as $category)
                if ($category->id == $id)
                    return $category;

            return null;
        }

        /**
         * Gets single category by its GUID path.
         * @param string $guidPath
         * @return Category|null
         */
        public function getByGuidPath ($guidPath)
        {
            foreach ($this->_data as $category)
                if ($category->guidPath === $guidPath)
                    return $category;

            return null;
        }

        /**
         * Setting for model class.
         * @param $class
         * @throws \yii\base\InvalidConfigException
         */
        public function setModelClass ($class)
        {
            if (!class_exists($class))
                throw new \yii\base\InvalidConfigException('Given model class not found.');
            $this->_modelClass = $class;
        }

        /**
         * Checks if category exists.
         * @param integer $id Category ID.
         * @return bool
         */
        public function exists ($id)
        {
            foreach ($this->_data as $category)
                if ($category->id == $id)
                    return true;

            return false;
        }

        /**
         * Reloads data from database.
         */
        public function reload ()
        {
            $class = $this->_modelClass;

            $this->_root = $class::find()->roots()->one();
            $this->_data = $this->_root->children()->all();
            $this->buildPaths();
        }

        /**
         * Finds category GUID path by given ID.
         * @param integer $id
         * @return null|string
         */
        public function guidPath ($id)
        {
            $category = $this->get($id);

            if ($category == null)
                return null;
            elseif (empty($category->guidPath))
                $this->buildPaths();

            return $category->guidPath;
        }

        /**
         * Finds category title path by given ID.
         * @param integer $id
         * @return null|string
         */
        public function titlePath ($id)
        {
            $category = $this->get($id);

            if ($category == null)
                return null;
            elseif (empty($category->titlePath))
                $this->buildPaths();

            return $category->titlePath;
        }

        /**
         * Builds full title and GUID paths for all categories.
         */
        protected function buildPaths ()
        {
            $titles = [];
            $guids = [];

            $n = count($this->_data);
            for ($i = 0; $i < $n; $i++)
            {
                $parent = $this->_data[ $i ];
                for ($j = $i + 1; $j < $n; $j++)
                {
                    $child = $this->_data[ $j ];
                    if ($child->lft > $parent->lft and $child->rgt < $parent->rgt)
                    {
                        $titles[ $child->id ][] = $parent->title;
                        $guids[ $child->id ][] = $parent->guid;
                    }
                }
                $titles[ $parent->id ][] = $parent->title;
                $guids[ $parent->id ][] = $parent->guid;

                $parent->titlePath = implode($this->_titlePathDelimiter, $titles[ $parent->id ]);
                $parent->guidPath = implode($this->_guidPathDelimiter, $guids[ $parent->id ]);
            }
        }
    }