edde-framework/edde-framework

<?php
    declare(strict_types=1);

    namespace Edde\Common\Node;

    use Edde\Api\Node\INode;
    use Edde\Api\Node\INodeQuery;
    use Edde\Common\Object;
    use Iterator;

    class NodeQuery extends Object implements INodeQuery {
        /**
         * @var string
         */
        protected $query;
        protected $filter;

        /**
         * @param string $query
         */
        public function __construct($query) {
            $this->query = $query;
        }

        /**
         * return first result of a query or null
         *
         * @param INode               $root
         * @param string              $query
         * @param mixed|callable|null $default
         *
         * @return INode|null|mixed
         */
        static public function first(INode $root, $query, $default = null) {
            $node = null;
            /** @noinspection LoopWhichDoesNotLoopInspection */
            foreach (self::node($root, $query) as $node) {
                break;
            }
            return $node ?: (is_callable($default) ? call_user_func($default) : $default);
        }

        /**
         * @param INode  $node
         * @param string $query
         *
         * @return INode[]
         */
        static public function node(INode $node, $query) {
            return self::create($query)->filter($node);
        }

        /**
         * @param string $query
         *
         * @return INodeQuery|INode[]
         */
        static public function create($query) {
            return new self($query);
        }

        /**
         * return last result of a query or null
         *
         * @param INode               $node
         * @param string              $query
         * @param mixed|callable|null $default
         *
         * @return INode|null|mixed
         */
        static public function last(INode $node, $query, $default = null) {
            $n = null;
            foreach (self::node($node, $query) as $n) {
                ;
            }
            return $n ?: (is_callable($default) ? call_user_func($default) : $default);
        }

        public function isEmpty(INode $node) {
            $iterator = $this->filter($node);
            $iterator->rewind();
            return $iterator->valid() === false;
        }

        public function filter(INode $node) {
            return $this->query(NodeIterator::recursive($node));
        }

        public function query(Iterator $iterator) {
            if ($this->filter === null) {
                $this->filter = $this->parse($this->query);
            }
            /** @var $node INode */
            foreach ($iterator as $node) {
                $level = $node->getLevel();
                if ($level < $this->filter->min) {
                    continue;
                }
                if ($this->filter->fixed && $level !== $this->filter->level) {
                    continue;
                }
                $path = $node->getPath($this->filter->attributes, $this->filter->metas);
                if (preg_match($this->filter->preg, $path) !== 1) {
                    continue;
                }
                yield $node;
            }
        }

        /**
         * token generator
         *
         * @param string $query
         *
         * @return \stdClass
         */
        protected function parse($query) {
            $query = str_replace('//', '/*/', $query);
            $query = '/' . trim($query, '/') . '/';
            $filter = new \stdClass();
            $filter->fixed = strpos($query, '**') === false && strpos($query, '?*') === false;
            $filter->static = strpos($query, '*') === false;
            if ($filter->fixed) {
                $filter->level = substr_count($query, '/') - 2;
            }
            $filter->attributes = strpos($query, '[') !== false && strpos($query, ']') !== false;
            $filter->metas = strpos($query, '(') !== false && strpos($query, ')') !== false;
            $filter->min = $filter->fixed ? $filter->level : min(($result = array_search('**', $explode = explode('/', trim($query, '/')), true)) === false ? PHP_INT_MAX : $result, ($result = array_search('?*', $explode, true)) === false ? PHP_INT_MAX : $result);

            $preg = null;
            foreach (explode('/', trim($query, '/')) as $fragment) {
                $name = 'a-zA-Z0-9_\\\\-';
                if ($fragment === '**') {
                    $preg .= '.*?/';
                    continue;
                } else if ($fragment === '?*') {
                    $preg .= '(.*?/)?';
                    continue;
                } else if ($fragment === '*') {
                    $preg .= '[' . $name . ']*(\\[.*?\\])*(\\(.*?\\))*(:\d+)?/';
                    continue;
                }
                $fragment = str_replace([
                    '[',
                    ']',
                    '(',
                    ')',
                ], [
                    '\\[',
                    '\\]',
                    '\\(',
                    '\\)',
                ], $fragment);
                if (preg_match('~^(\\\\[[' . $name . ']+\\\\])+$~', $fragment)) {
                    $fragment = '.*?' . $fragment;
                }
                if (preg_match('~^[' . $name . ']+$~', $fragment)) {
                    $fragment .= '(\\[.*?\\])*(\\(.*?\\))*';
                }
                $preg .= $fragment . '(:\d+)?/';
            }

            $filter->preg = '~^/' . rtrim($preg, '/') . '$~';

            return $filter;
        }
    }