<?php

class MyParsedown extends ParsedownExtended {

    function __construct(
        ?array         $opts = null,
        protected bool $useImagePreviews = false
    ) {
        $parsedown_opts = [
            'tables' => [
                'tablespan' => true
            ]
        ];
        if (!is_null($opts)) {
            $parsedown_opts = array_merge($parsedown_opts, $opts);
        }
        parent::__construct($parsedown_opts);

        $this->InlineTypes['{'][] = 'FileAttach';
        $this->InlineTypes['{'][] = 'Image';
        $this->InlineTypes['{'][] = 'Video';
        $this->inlineMarkerList .= '{';
    }

    protected function inlineFileAttach($excerpt) {
        if (preg_match('/^{fileAttach:([\w]{8})}{\/fileAttach}/', $excerpt['text'], $matches)) {
            $random_id = $matches[1];
            $upload = uploads::getUploadByRandomId($random_id);
            $result = [
                'extent' => strlen($matches[0]),
                'element' => [
                    'name' => 'span',
                    'text' => '',
                ],
                'type' => ''
            ];

            if (!$upload) {
                return $result;
            }

            unset($result['element']['text']);

            $ctx = self::getSkinContext();
            $result['element']['rawHtml'] = $ctx->fileupload($upload->name, $upload->getDirectUrl(), $upload->note, $upload->getSize());

            return $result;
        }
    }

    protected function inlineImage($excerpt) {
        global $config;

        if (preg_match('/^{image:([\w]{8}),(.*?)}{\/image}/', $excerpt['text'], $matches)) {
            $random_id = $matches[1];

            $opts = [
                'w' => 'auto',
                'h' => 'auto',
                'align' => 'left',
                'nolabel' => false,
            ];
            $inputopts = explode(',', $matches[2]);

            foreach ($inputopts as $opt) {
                if ($opt == 'nolabel')
                    $opts[$opt] = true;
                else {
                    list($k, $v) = explode('=', $opt);
                    if (!isset($opts[$k]))
                        continue;
                    $opts[$k] = $v;
                }
            }

            $image = uploads::getUploadByRandomId($random_id);
            $result = [
                'extent' => strlen($matches[0]),
                'element' => [
                    'name' => 'span',
                    'text' => '',
                ],
                'type' => ''
            ];

            if (!$image) {
                return $result;
            }

            list($w, $h) = $image->getImagePreviewSize(
                $opts['w'] == 'auto' ? null : $opts['w'],
                $opts['h'] == 'auto' ? null : $opts['h']
            );
            $opts['w'] = $w;
            // $opts['h'] = $h;

            if (!$this->useImagePreviews)
                $image_url = $image->getDirectUrl();
            else
                $image_url = $image->getDirectPreviewUrl($w, $h);

            unset($result['element']['text']);

            $ctx = self::getSkinContext();
            $result['element']['rawHtml'] = $ctx->image(
                w: $opts['w'],
                nolabel: $opts['nolabel'],
                align: $opts['align'],
                padding_top: round($h / $w * 100, 4),
                may_have_alpha: $image->imageMayHaveAlphaChannel(),

                url: $image_url,
                direct_url: $image->getDirectUrl(),
                note: $image->note
            );

            return $result;
        }
    }

    protected function inlineVideo($excerpt) {
        if (preg_match('/^{video:([\w]{8})(?:,(.*?))?}{\/video}/', $excerpt['text'], $matches)) {
            $random_id = $matches[1];

            $opts = [
                'w' => 'auto',
                'h' => 'auto',
                'align' => 'left',
                'nolabel' => false,
            ];
            $inputopts = !empty($matches[2]) ? explode(',', $matches[2]) : [];

            foreach ($inputopts as $opt) {
                if ($opt == 'nolabel')
                    $opts[$opt] = true;
                else {
                    list($k, $v) = explode('=', $opt);
                    if (!isset($opts[$k]))
                        continue;
                    $opts[$k] = $v;
                }
            }

            $video = uploads::getUploadByRandomId($random_id);
            $result = [
                'extent' => strlen($matches[0]),
                'element' => [
                    'name' => 'span',
                    'text' => '',
                ],
                'type' => ''
            ];

            if (!$video) {
                return $result;
            }

            $video_url = $video->getDirectUrl();

            unset($result['element']['text']);

            $ctx = self::getSkinContext();
            $result['element']['rawHtml'] = $ctx->video(
                url: $video_url,
                w: $opts['w'],
                h: $opts['h']
            );

            return $result;
        }
    }

    protected function paragraph($line) {
        if (preg_match('/^{fileAttach:([\w]{8})}{\/fileAttach}$/', $line['text'])) {
            return $this->inlineFileAttach($line);
        }
        if (preg_match('/^{image:([\w]{8}),(?:.*?)}{\/image}/', $line['text'])) {
            return $this->inlineImage($line);
        }
        if (preg_match('/^{video:([\w]{8})(?:,(?:.*?))?}{\/video}/', $line['text'])) {
            return $this->inlineVideo($line);
        }
        return parent::paragraph($line);
    }

    protected function blockFencedCodeComplete($block) {
        if (!isset($block['element']['element']['attributes'])) {
            return $block;
        }

        $code = $block['element']['element']['text'];
        $languageClass = $block['element']['element']['attributes']['class'];
        $language = explode('-', $languageClass);

        if ($language[1] == 'term') {
            $lines = explode("\n", $code);
            for ($i = 0; $i < count($lines); $i++) {
                $line = $lines[$i];
                if (str_starts_with($line, '$ ') || str_starts_with($line, '# ')) {
                    $lines[$i] = '<span class="term-prompt">'.substr($line, 0, 2).'</span>'.htmlspecialchars(substr($line, 2), ENT_NOQUOTES, 'UTF-8');
                } else {
                    $lines[$i] = htmlspecialchars($line, ENT_NOQUOTES, 'UTF-8');
                }
            }
            $block['element']['element']['rawHtml'] = implode("\n", $lines);
            unset($block['element']['element']['text']);

            return $block;
        }

        return parent::blockFencedCodeComplete($block);
    }

    protected static function getSkinContext(): SkinContext {
        return new SkinContext('\\skin\\markdown');
    }

    protected function blockTableComplete(array $Block)
    {
        if ( ! isset($Block))
        {
            return null;
        }

        $HeaderElements =& $Block['element']['elements'][0]['elements'][0]['elements'];

        for ($index = count($HeaderElements) - 1; $index >= 0; --$index)
        {
            $colspan = 1;
            $HeaderElement =& $HeaderElements[$index];

            while ($index && $HeaderElements[$index - 1]['handler']['argument'] === '>')
            {
                $colspan++;
                $PreviousHeaderElement =& $HeaderElements[--$index];
                $PreviousHeaderElement['merged'] = true;
                if (isset($PreviousHeaderElement['attributes']))
                {
                    $HeaderElement['attributes'] = $PreviousHeaderElement['attributes'];
                }
            }

            if ($colspan > 1)
            {
                if ( ! isset($HeaderElement['attributes']))
                {
                    $HeaderElement['attributes'] = array();
                }
                $HeaderElement['attributes']['colspan'] = $colspan;
            }
        }

        for ($index = count($HeaderElements) - 1; $index >= 0; --$index)
        {
            if (isset($HeaderElements[$index]['merged']))
            {
                array_splice($HeaderElements, $index, 1);
            }
        }

        $Rows =& $Block['element']['elements'][1]['elements'];

        foreach ($Rows as $RowNo => &$Row)
        {
            $Elements =& $Row['elements'];

            for ($index = count($Elements) - 1; $index >= 0; --$index)
            {
                $colspan = 1;
                $Element =& $Elements[$index];

                while ($index && $Elements[$index - 1]['handler']['argument'] === '>')
                {
                    $colspan++;
                    $PreviousElement =& $Elements[--$index];
                    $PreviousElement['merged'] = true;
                    if (isset($PreviousElement['attributes']))
                    {
                        $Element['attributes'] = $PreviousElement['attributes'];
                    }
                }

                if ($colspan > 1)
                {
                    if ( ! isset($Element['attributes']))
                    {
                        $Element['attributes'] = array();
                    }
                    $Element['attributes']['colspan'] = $colspan;
                }
            }
        }

        foreach ($Rows as $RowNo => &$Row)
        {
            $Elements =& $Row['elements'];

            foreach ($Elements as $index => &$Element)
            {
                $rowspan = 1;

                if (isset($Element['merged']))
                {
                    continue;
                }

                while ($RowNo + $rowspan < count($Rows) && $index < count($Rows[$RowNo + $rowspan]['elements']) && $Rows[$RowNo + $rowspan]['elements'][$index]['handler']['argument'] === '^' && (@$Element['attributes']['colspan'] ?: null) === (@$Rows[$RowNo + $rowspan]['elements'][$index]['attributes']['colspan'] ?: null))
                {
                    $Rows[$RowNo + $rowspan]['elements'][$index]['merged'] = true;
                    $rowspan++;
                }

                if ($rowspan > 1)
                {
                    if ( ! isset($Element['attributes']))
                    {
                        $Element['attributes'] = array();
                    }
                    $Element['attributes']['rowspan'] = $rowspan;
                }
            }
        }

        foreach ($Rows as $RowNo => &$Row)
        {
            $Elements =& $Row['elements'];

            for ($index = count($Elements) - 1; $index >= 0; --$index)
            {
                if (isset($Elements[$index]['merged']))
                {
                    array_splice($Elements, $index, 1);
                }
            }
        }

        return $Block;
    }

}