<?php

declare(strict_types=1);

namespace Pcm\IconBundle\Twig\Functions;

use InvalidArgumentException;
use Twig\Extension\AbstractExtension;
use Twig\TwigFunction;

final class IconExtension extends AbstractExtension
{
    public const DEFAULT_SIZE = 32;

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

    public function __construct(private array $directories, private array $palletes)
    {
        if (empty($this->directories))
            throw new InvalidArgumentException('Directories array must contain at least one path!');

        $dirsContainNonString = array_reduce($this->directories,
            fn($notString, $path) => $notString || !is_string($path));

        if ($dirsContainNonString)
            throw new \TypeError('Directories array must only contain strings!');

        if (empty($this->palletes))
            throw new InvalidArgumentException('Palletes array must contain at least one pallet!');

        $pelletesContainNonarray = array_reduce($this->palletes,
            fn($notArray, $path) => $notArray || !is_array($path));

        if ($pelletesContainNonarray)
            throw new \TypeError('Palletes array must only contain arrays!');

        foreach ($this->palletes as $pallete) {
            if (!(array_key_exists('stroke', $pallete) && array_key_exists('fill', $pallete))) {
                throw new \Exception('Palletes must contain a "stroke" and "fill" key!');
            }
        }
    }

    /**
     * @inheritDoc
     */
    public function getFunctions(): array
    {
        return [
            new TwigFunction('icon', [$this, 'renderIcon'], [
                'is_safe' => ['html']
            ])
        ];
    }

    /**
     * @param array $options
     * ```
     * $options = [
     *     'icon'   => (string) Which icon to use
     *     'title'  => (?string) Text to appear on mouse hover
     *     'size'   => (int) Height and width in px
     *     'colour' => (string) Main colour pallete
     * ]
     * ```
     */
    public function renderIcon(array $userOptions): string
    {
        $options = $this->mergeUserOptionsWithDefaults($userOptions);

        $iconFilepath = $this->findSvgFilepath($options['icon']);
        $rawSvgMarkup = $this->getSvgMarkup($iconFilepath);
        $cleanSvgMarkup = $this->cleanSvgMarkup($rawSvgMarkup);

        $mainPallete = $this->getMainPallete($options['colour']);

        $xml = new \SimpleXMLElement($cleanSvgMarkup);
        $xml = $this->addAttributeToXmlElement($xml, 'class', $mainPallete['stroke'] . ' ' . $mainPallete['fill']);
        $markup = $this->removeXMLDeclaration($xml->saveXML());

        if ($this->isNonEmptyString($options['title']))
            $markup = $this->addTitleToMarkup($markup, $options['title']);

        if ($options['size'] < 0)
            throw new \InvalidArgumentException('Size must not be negative');

        if (!is_int($options['size']))
            throw new \TypeError('Size value must be an integer');

        $markup = $this->setSize($markup, $options['size']);
        $markup = $this->removeBlackStrokeAttributes($markup);
        $markup = $this->removeBlackFillAttributes($markup);

        return $markup;
    }

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

    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 getSvgMarkup(string $filepath): string
    {
        return file_get_contents($filepath);
    }

    private function cleanSvgMarkup(string $markup): string
    {
        return preg_replace('/<title>.*<\/title>/', '', $markup);
    }

    private function getMainPallete(string $palleteName): array
    {
        if (array_key_exists($palleteName, $this->palletes))
            return $this->palletes[$palleteName];

        throw new PalleteNotFound("The pallete '$palleteName' was not found!");
    }

    private function isNonEmptyString(mixed $title): bool
    {
        if (!is_string($title) && null !== $title)
            throw new \TypeError('Title must be a string!');

        if ('' === $title)
            throw new \InvalidArgumentException('Title string must not be empty!');

        return true;
    }

    private function addTitleToMarkup(string $markup, ?string $title): string
    {
        if (null === $title)
            return $markup;

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

    private function setSize(string $content, int $size): string
    {
        $svgAsXmlElement = new \SimpleXMLElement($content);
        $svgAsXmlElement = $this->addAttributeToXmlElement($svgAsXmlElement, 'width', $size);
        $svgAsXmlElement = $this->addAttributeToXmlElement($svgAsXmlElement, 'height', $size);
        return $this->removeXMLDeclaration($svgAsXmlElement->saveXML());
    }

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

    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 removeBlackStrokeAttributes(string $content): string
    {
        return preg_replace('/stroke="\s*(#0{6}|#000|rgb\(\s*0,\s*0,\s*0\s*\)|black)\s*"/', '', $content);
    }

    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);
    }
}

class IconNotFound extends \Exception {};

class PalleteNotFound extends \Exception {};

// class="stroke-neutral-400 fill-neutral-400"

// hover:stroke-ses-highlight
// group-hover:stroke-ses-highlight

// hover:fill-ses-highlight
// group-hover:fill-ses-highlight

// cursor-pointer