<?php

namespace MoeBrowne\SmartImage;

use League\CommonMark\Extension\CommonMark\Node\Inline\Image;
use League\CommonMark\Node\Inline\Newline;
use League\CommonMark\Node\Node;
use League\CommonMark\Node\NodeIterator;
use League\CommonMark\Node\StringContainerInterface;
use League\CommonMark\Renderer\ChildNodeRendererInterface;
use League\CommonMark\Renderer\NodeRendererInterface;
use League\CommonMark\Util\HtmlElement;
use League\CommonMark\Util\RegexHelper;
use League\CommonMark\Xml\XmlNodeRendererInterface;
use League\Config\ConfigurationAwareInterface;
use League\Config\ConfigurationInterface;

final class SmartImageRenderer implements NodeRendererInterface, XmlNodeRendererInterface, ConfigurationAwareInterface
{
    /** @psalm-readonly-allow-private-mutation */
    private ConfigurationInterface $config;

    /**
     * @param Image $node
     *
     * {@inheritDoc}
     *
     * @psalm-suppress MoreSpecificImplementedParamType
     */
    public function render(Node $node, ChildNodeRendererInterface $childRenderer): string|\Stringable
    {
        Image::assertInstanceOf($node);

        $attrs = $node->data->get('attributes');

        $forbidUnsafeLinks = ! $this->config->get('allow_unsafe_links');
        if ($forbidUnsafeLinks && RegexHelper::isLinkPotentiallyUnsafe($node->getUrl())) {
            $attrs['src'] = '';
        } else {
            $attrs['src'] = $node->getUrl();
        }

        $attrs['alt'] = $this->getAltText($node);

        if (($title = $node->getTitle()) !== null) {
            $attrs['title'] = $title;
        }

        if (str_starts_with($node->getUrl(), 'https://') === false) {
            $imagePath = __DIR__ . '/../../public/' . $node->getUrl();

            if (file_exists($imagePath) === false) {
                return '';
            }

            $imageSize = getimagesize($imagePath);

            if ($imageSize !== false) {
                $attrs['width'] = (string)$imageSize[0];
                $attrs['height'] = (string)$imageSize[1];
                $attrs['style'] = 'max-height: ' . min((int)$attrs['height'] + 60, 540)  . 'px';
            }

            $attrs['loading'] = 'lazy';
        }

        return new HtmlElement('img', $attrs, '', true);
    }

    public function setConfiguration(ConfigurationInterface $configuration): void
    {
        $this->config = $configuration;
    }

    public function getXmlTagName(Node $node): string
    {
        return 'image';
    }

    /**
     * @param Image $node
     *
     * @return array<string, scalar>
     *
     * @psalm-suppress MoreSpecificImplementedParamType
     */
    public function getXmlAttributes(Node $node): array
    {
        Image::assertInstanceOf($node);

        return [
            'destination' => $node->getUrl(),
            'title' => $node->getTitle() ?? '',
        ];
    }

    private function getAltText(Image $node): string
    {
        $altText = '';

        foreach ((new NodeIterator($node)) as $n) {
            if ($n instanceof StringContainerInterface) {
                $altText .= $n->getLiteral();
            } elseif ($n instanceof Newline) {
                $altText .= "\n";
            }
        }

        return $altText;
    }
}