pcm-icon-bundle/src/Twig/Runtime/IconRuntime.php

<?php

declare(strict_types=1);

namespace Pcm\IconBundle\Twig\Runtime;

use Pcm\IconBundle\Exception\ColourNotFound;
use Pcm\IconBundle\Exception\IconNotFound;
use Twig\Extension\RuntimeExtensionInterface;

final class IconRuntime implements RuntimeExtensionInterface
{
    public const DEFAULT_SIZE = 32;
    public const DEFAULT_COLOUR = 'primary';

    private const DEFAULT_OPTIONS = [
        'icon'    => null,
        'title'   => null,
        'size'    => self::DEFAULT_SIZE,
        'colour'  => self::DEFAULT_COLOUR,
        'hover'   => null,
        'classes' => [],
    ];

    public function __construct(private array $directories, private array $colours)
    {}

    /**
     * @param array $options
     * ```
     * $options = [
     *     'icon'    => (string)  **REQUIRED** Icon name without trailing `.svg`
     *     'title'   => (?string) Title text to appear on mouse hover
     *     'size'    => (int)     Height and width in px
     *     'colour'  => (string)  Main colour
     *     'hover'   => (?string) Hover colour
     *     'classes' => (array)   Additional classes to add to the icon. Not recommended.
     * ]
     * ```
     *
     * @return string Processed SVG
     */
    public function renderIcon(array $userOptions): string
    {
        $options = $this->mergeWithDefaultOptions($userOptions);

        $svg = $this->getSvg($options['icon']);
        $svg = $this->sanitiseSvg($svg);

        $colourClasses = $this->getColourClasses($options['colour'], $options['hover']);
        $extraClasses = $this->getExtraClasses($options['classes']);

        $classes = trim($colourClasses.' '.$extraClasses);
        $this->addClassesToSvg($svg, $classes);

        if (null !== $options['title']) {
            $this->addTitleToSvg($svg, $options['title']);
        }

        $this->setSvgHeightAndWidth($svg, $options['size']);

        return $svg;
    }

    private function getExtraClasses(array $extraClasses): string
    {
        return implode(' ', $extraClasses);
    }

    private function mergeWithDefaultOptions(array $userOptions): array
    {
        $this->throwIfUnrecognisedOptionExists($userOptions);
        return $this->mergeUserOptionsWithDefaults($userOptions);
    }

    private function mergeUserOptionsWithDefaults(array $userOptions): array
    {
        return array_merge(self::DEFAULT_OPTIONS, $userOptions);
    }

    private function throwIfUnrecognisedOptionExists(array $options): void
    {
        foreach (array_keys($options) as $key) {
            if (!key_exists($key, self::DEFAULT_OPTIONS)) {
                throw new \InvalidArgumentException("Unrecognised option '{$key}'!");
            }
        }
    }

    private function getSvg(string $iconName): string
    {
        $iconFilepath = $this->findSvgFilepath($iconName);
        return file_get_contents($iconFilepath);
    }

    private function sanitiseSvg(string &$svg): string
    {
        $this->removeExistingTitleElement($svg);
        $this->removeBlackStrokeAttributes($svg);
        $this->removeStrokeCurrentColor($svg);

        return $this->removeBlackFillAttributes($svg);
    }

    private function findSvgFilepath(string $iconName): string
    {
        foreach ($this->directories as $directory) {
            $potentialFilepath = sprintf('%s/%s.svg', $directory, $iconName);

            if (file_exists($potentialFilepath)) {
                return $potentialFilepath;
            }
        }

        throw new IconNotFound(sprintf('File "%s.svg" not found in %s', $iconName, implode(', ', $this->directories)));
    }

    private function removeExistingTitleElement(string &$svg): void
    {
        $svg = preg_replace('/<title>.*<\/title>/', '', $svg);
    }

    private function removeBlackStrokeAttributes(string &$svg): void
    {
        $svg = preg_replace('/stroke(=|:)"?\s*(#0{6}|#000|rgb\(\s*0,\s*0,\s*0\s*\)|black)\s*"?/', '', $svg);
    }

    private function removeStrokeCurrentColor(string &$svg): void
    {
        $svg = \preg_replace('/stroke=(\'|")currentColor(\'|")/', '', $svg);
    }

    private function removeBlackFillAttributes(string $content): string
    {
        return preg_replace('/fill(=|:)"?\s*(#0{6}|#000|rgb\(\s*0,\s*0,\s*0\s*\)|black)\s*"?/', '', $content);
    }

    private function getColourClasses(string $primaryColour, ?string $hoverColour): string
    {
        $mainColour = $this->getColour($primaryColour);
        $colourClasses = "{$mainColour['stroke']} {$mainColour['fill']}";

        if (null !== $hoverColour) {
            $hoverColour = $this->getColour($hoverColour);
            $colourClasses .= " cursor-pointer {$hoverColour['stroke-hover']} {$hoverColour['fill-hover']} {$hoverColour['stroke-group-hover']} {$hoverColour['fill-group-hover']}";
        }

        return $colourClasses;
    }

    private function getColour(string $colourName): array
    {
        if (array_key_exists($colourName, $this->colours)) {
            return $this->colours[$colourName];
        }

        throw new ColourNotFound("The colour \"$colourName\" was not found!");
    }

    private function addClassesToSvg(string &$svg, string $classes): void
    {
        $xml = new \SimpleXMLElement($svg);
        $xml = $this->addAttributeToXmlElement($xml, 'class', $classes);
        $svg = $this->removeXMLDeclaration($xml->saveXML());
    }

    private function addTitleToSvg(string &$svg, ?string $title): void
    {
        if ('' === $title) {
            throw new \InvalidArgumentException('Title must not be an empty string!');
        }

        $svg = preg_replace('/(<svg(.|\n)*?>\n?)/', "$1<title>$title</title>", $svg);
    }

    private function addAttributeToXmlElement(\SimpleXMLElement $xml, string $attrName, mixed $attrValue): \SimpleXMLElement
    {
        if (isset($xml->attributes()->$attrName)) {
            $xml->attributes()->$attrName = strval($attrValue);
        } else {
            $xml->addAttribute($attrName, strval($attrValue));
        }

        return $xml;
    }

    private function removeXMLDeclaration(string $content): string
    {
        return trim(preg_replace('/<\?xml.*\?>/', '', $content));
    }

    private function setSvgHeightAndWidth(string &$svg, int $size): void
    {
        if ($size < 0) {
            throw new \InvalidArgumentException('Size must not be negative');
        }

        $svgAsXml = new \SimpleXMLElement($svg);
        $svgAsXml = $this->addAttributeToXmlElement($svgAsXml, 'width', $size);
        $svgAsXml = $this->addAttributeToXmlElement($svgAsXml, 'height', $size);

        $svg = $this->removeXMLDeclaration($svgAsXml->saveXML());
    }
}