t1gor/Robots.txt-Parser-Class

<?php declare(strict_types=1);

namespace t1gor\RobotsTxtParser\Parser;

use Psr\Log\LoggerInterface;
use Psr\Log\LogLevel;
use t1gor\RobotsTxtParser\LogsIfAvailableTrait;
use t1gor\RobotsTxtParser\Parser\DirectiveProcessors\DirectiveProcessorInterface;

class TreeBuilder implements TreeBuilderInterface {

    use LogsIfAvailableTrait;

    /**
     * @var DirectiveProcessorInterface[]
     */
    protected array     $processors;
    protected \Iterator $content;

    /**
     * @param DirectiveProcessorInterface[] $processors
     * @param LoggerInterface|null          $logger
     */
    public function __construct(array $processors, ?LoggerInterface $logger) {
        $this->logger = $logger;

        if (empty($processors)) {
            $this->log("Seems like you've passed an empty processors array.", [], LogLevel::WARNING);
        }

        // reformat processors
        foreach ($processors as $processor) {
            $this->processors[$processor->getDirectiveName()] = $processor;
        }
    }

    /**
     * Wrapper to check that processor is available
     */
    protected function processDirective(string $directive, string $line, &$tree, string &$userAgent, string $prevLine = '') {
        if (!isset($this->processors[$directive])) {
            $this->log(strtr('{directive} met, but no processor found for it. Skipping.', [
                '{directive}' => $directive,
            ]));
            return;
        }

        $this->processors[$directive]->process($line, $tree, $userAgent, $prevLine);
    }

    /**
     * @return \Iterator
     */
    public function getContent(): \Iterator {
        return $this->content;
    }

    /**
     * @param \Iterator $content
     */
    public function setContent(\Iterator $content): void {
        $this->content = $content;
    }

    /**
     * @return array
     * @todo check for multibyte support?
     */
    public function build(): array {
        $currentUserAgent = '*';
        $tree             = [];
        $prevLine         = '';

        $this->log('Building directives tree...');

        foreach ($this->content as $line) {
            foreach ($this->processors as $processor) {
                if ($processor->matches($line)) {
                    $this->processDirective(
                        $processor->getDirectiveName(),
                        $line,
                        $tree,
                        $currentUserAgent,
                        $prevLine
                    );
                    break;
                }
            }

            // override
            $prevLine = $line;
        }

        return $tree;
    }
}