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Diffstat (limited to 'vendor/soundasleep/html2text/src/Html2Text.php')
| -rw-r--r-- | vendor/soundasleep/html2text/src/Html2Text.php | 540 |
1 files changed, 540 insertions, 0 deletions
diff --git a/vendor/soundasleep/html2text/src/Html2Text.php b/vendor/soundasleep/html2text/src/Html2Text.php new file mode 100644 index 000000000..1763cb4a4 --- /dev/null +++ b/vendor/soundasleep/html2text/src/Html2Text.php @@ -0,0 +1,540 @@ +<?php + +namespace Soundasleep; + +class Html2Text { + + /** @return array<string, bool | string> */ + public static function defaultOptions(): array { + return [ + 'ignore_errors' => false, + 'drop_links' => false, + 'char_set' => 'auto' + ]; + } + + /** + * Tries to convert the given HTML into a plain text format - best suited for + * e-mail display, etc. + * + * <p>In particular, it tries to maintain the following features: + * <ul> + * <li>Links are maintained, with the 'href' copied over + * <li>Information in the <head> is lost + * </ul> + * + * @param string $html the input HTML + * @param boolean|array<string, bool | string> $options if boolean, Ignore xml parsing errors, else ['ignore_errors' => false, 'drop_links' => false, 'char_set' => 'auto'] + * @return string the HTML converted, as best as possible, to text + * @throws Html2TextException if the HTML could not be loaded as a {@link \DOMDocument} + */ + public static function convert(string $html, $options = []): string { + + if ($options === false || $options === true) { + // Using old style (< 1.0) of passing in options + $options = ['ignore_errors' => $options]; + } + + $options = array_merge(static::defaultOptions(), $options); + + // check all options are valid + foreach ($options as $key => $value) { + if (!in_array($key, array_keys(static::defaultOptions()))) { + throw new \InvalidArgumentException("Unknown html2text option '$key'. Valid options are " . implode(',', static::defaultOptions())); + } + } + + $is_office_document = self::isOfficeDocument($html); + + if ($is_office_document) { + // remove office namespace + $html = str_replace(["<o:p>", "</o:p>"], "", $html); + } + + $html = self::fixNewlines($html); + + // use mb_convert_encoding for legacy versions of php + if (PHP_MAJOR_VERSION * 10 + PHP_MINOR_VERSION < 81 && mb_detect_encoding($html, "UTF-8", true)) { + $html = mb_convert_encoding($html, "HTML-ENTITIES", "UTF-8"); + } + + $doc = self::getDocument($html, $options); + + $output = self::iterateOverNode($doc, null, false, $is_office_document, $options); + + // process output for whitespace/newlines + $output = self::processWhitespaceNewlines($output); + + return $output; + } + + /** + * Unify newlines; in particular, \r\n becomes \n, and + * then \r becomes \n. This means that all newlines (Unix, Windows, Mac) + * all become \ns. + * + * @param string $text text with any number of \r, \r\n and \n combinations + * @return string the fixed text + */ + public static function fixNewlines(string $text): string { + // replace \r\n to \n + $text = str_replace("\r\n", "\n", $text); + // remove \rs + $text = str_replace("\r", "\n", $text); + + return $text; + } + + /** @return array<string> */ + public static function nbspCodes(): array { + return [ + "\xc2\xa0", + "\u00a0", + ]; + } + + /** @return array<string> */ + public static function zwnjCodes(): array { + return [ + "\xe2\x80\x8c", + "\u200c", + ]; + } + + /** + * Remove leading or trailing spaces and excess empty lines from provided multiline text + * + * @param string $text multiline text any number of leading or trailing spaces or excess lines + * @return string the fixed text + */ + public static function processWhitespaceNewlines(string $text): string { + + // remove excess spaces around tabs + $text = preg_replace("/ *\t */im", "\t", $text); + + // remove leading whitespace + $text = ltrim($text); + + // remove leading spaces on each line + $text = preg_replace("/\n[ \t]*/im", "\n", $text); + + // convert non-breaking spaces to regular spaces to prevent output issues, + // do it here so they do NOT get removed with other leading spaces, as they + // are sometimes used for indentation + $text = self::renderText($text); + + // remove trailing whitespace + $text = rtrim($text); + + // remove trailing spaces on each line + $text = preg_replace("/[ \t]*\n/im", "\n", $text); + + // unarmor pre blocks + $text = self::fixNewLines($text); + + // remove unnecessary empty lines + $text = preg_replace("/\n\n\n*/im", "\n\n", $text); + + return $text; + } + + /** + * Can we guess that this HTML is generated by Microsoft Office? + */ + public static function isOfficeDocument(string $html): bool { + return strpos($html, "urn:schemas-microsoft-com:office") !== false; + } + + public static function isWhitespace(string $text): bool { + return strlen(trim(self::renderText($text), "\n\r\t ")) === 0; + } + + /** + * Parse HTML into a DOMDocument + * + * @param string $html the input HTML + * @param array<string, bool | string> $options + * @return \DOMDocument the parsed document tree + */ + private static function getDocument(string $html, array $options): \DOMDocument { + + $doc = new \DOMDocument(); + + $html = trim($html); + + if (!$html) { + // DOMDocument doesn't support empty value and throws an error + // Return empty document instead + return $doc; + } + + if ($html[0] !== '<') { + // If HTML does not begin with a tag, we put a body tag around it. + // If we do not do this, PHP will insert a paragraph tag around + // the first block of text for some reason which can mess up + // the newlines. See pre.html test for an example. + $html = '<body>' . $html . '</body>'; + } + + $header = ''; + // use char sets for modern versions of php + if (PHP_MAJOR_VERSION * 10 + PHP_MINOR_VERSION >= 81) { + // use specified char_set, or auto detect if not set + $char_set = ! empty($options['char_set']) ? $options['char_set'] : 'auto'; + if ('auto' === $char_set) { + $char_set = mb_detect_encoding($html); + } else if (strpos($char_set, ',')) { + mb_detect_order($char_set); + $char_set = mb_detect_encoding($html); + } + // turn off error detection for Windows-1252 legacy html + if (strpos($char_set, '1252')) { + $options['ignore_errors'] = true; + } + $header = '<?xml version="1.0" encoding="' . $char_set . '">'; + } + + if (! empty($options['ignore_errors'])) { + $doc->strictErrorChecking = false; + $doc->recover = true; + $doc->xmlStandalone = true; + $old_internal_errors = libxml_use_internal_errors(true); + $load_result = $doc->loadHTML($header . $html, LIBXML_NOWARNING | LIBXML_NOERROR | LIBXML_NONET | LIBXML_PARSEHUGE); + libxml_use_internal_errors($old_internal_errors); + } + else { + $load_result = $doc->loadHTML($header . $html); + } + + if (!$load_result) { + throw new Html2TextException("Could not load HTML - badly formed?", $html); + } + + return $doc; + } + + /** + * Replace any special characters with simple text versions, to prevent output issues: + * - Convert non-breaking spaces to regular spaces; and + * - Convert zero-width non-joiners to '' (nothing). + * + * This is to match our goal of rendering documents as they would be rendered + * by a browser. + */ + private static function renderText(string $text): string { + $text = str_replace(self::nbspCodes(), " ", $text); + $text = str_replace(self::zwnjCodes(), "", $text); + return $text; + } + + private static function nextChildName(?\DOMNode $node): ?string { + // get the next child + $nextNode = $node->nextSibling; + while ($nextNode != null) { + if ($nextNode instanceof \DOMText) { + if (!self::isWhitespace($nextNode->wholeText)) { + break; + } + } + + if ($nextNode instanceof \DOMElement) { + break; + } + + $nextNode = $nextNode->nextSibling; + } + + $nextName = null; + if (($nextNode instanceof \DOMElement || $nextNode instanceof \DOMText) && $nextNode != null) { + $nextName = strtolower($nextNode->nodeName); + } + + return $nextName; + } + + /** @param array<string, bool | string> $options */ + private static function iterateOverNode(\DOMNode $node, ?string $prevName, bool $in_pre, bool $is_office_document, array $options): string { + if ($node instanceof \DOMText) { + // Replace whitespace characters with a space (equivilant to \s) + if ($in_pre) { + $text = "\n" . trim(self::renderText($node->wholeText), "\n\r\t ") . "\n"; + + // Remove trailing whitespace only + $text = preg_replace("/[ \t]*\n/im", "\n", $text); + + // armor newlines with \r. + return str_replace("\n", "\r", $text); + + } + $text = self::renderText($node->wholeText); + $text = preg_replace("/[\\t\\n\\f\\r ]+/im", " ", $text); + + if (!self::isWhitespace($text) && ($prevName == 'p' || $prevName == 'div')) { + return "\n" . $text; + } + return $text; + } + + if ($node instanceof \DOMDocumentType || $node instanceof \DOMProcessingInstruction) { + // ignore + return ""; + } + + $name = strtolower($node->nodeName); + $nextName = self::nextChildName($node); + + // start whitespace + switch ($name) { + case "hr": + $prefix = ''; + if ($prevName != null) { + $prefix = "\n"; + } + return $prefix . "---------------------------------------------------------------\n"; + + case "style": + case "head": + case "title": + case "meta": + case "script": + // ignore these tags + return ""; + + case "h1": + case "h2": + case "h3": + case "h4": + case "h5": + case "h6": + case "ol": + case "ul": + case "pre": + // add two newlines + $output = "\n\n"; + break; + + case "td": + case "th": + // add tab char to separate table fields + $output = "\t"; + break; + + case "p": + // Microsoft exchange emails often include HTML which, when passed through + // html2text, results in lots of double line returns everywhere. + // + // To fix this, for any p element with a className of `MsoNormal` (the standard + // classname in any Microsoft export or outlook for a paragraph that behaves + // like a line return) we skip the first line returns and set the name to br. + // @phpstan-ignore-next-line + if ($is_office_document && $node->getAttribute('class') == 'MsoNormal') { + $output = ""; + $name = 'br'; + break; + } + + // add two lines + $output = "\n\n"; + break; + + case "tr": + // add one line + $output = "\n"; + break; + + case "div": + $output = ""; + if ($prevName !== null) { + // add one line + $output .= "\n"; + } + break; + + case "li": + $output = "- "; + break; + + default: + // print out contents of unknown tags + $output = ""; + break; + } + + // debug + //$output .= "[$name,$nextName]"; + + if (isset($node->childNodes)) { + + $n = $node->childNodes->item(0); + $previousSiblingNames = []; + $previousSiblingName = null; + + $parts = []; + $trailing_whitespace = 0; + + while ($n != null) { + + $text = self::iterateOverNode($n, $previousSiblingName, $in_pre || $name == 'pre', $is_office_document, $options); + + // Pass current node name to next child, as previousSibling does not appear to get populated + if ($n instanceof \DOMDocumentType + || $n instanceof \DOMProcessingInstruction + || ($n instanceof \DOMText && self::isWhitespace($text))) { + // Keep current previousSiblingName, these are invisible + $trailing_whitespace++; + } + else { + $previousSiblingName = strtolower($n->nodeName); + $previousSiblingNames[] = $previousSiblingName; + $trailing_whitespace = 0; + } + + $node->removeChild($n); + $n = $node->childNodes->item(0); + + $parts[] = $text; + } + + // Remove trailing whitespace, important for the br check below + while ($trailing_whitespace-- > 0) { + array_pop($parts); + } + + // suppress last br tag inside a node list if follows text + $last_name = array_pop($previousSiblingNames); + if ($last_name === 'br') { + $last_name = array_pop($previousSiblingNames); + if ($last_name === '#text') { + array_pop($parts); + } + } + + $output .= implode('', $parts); + } + + // end whitespace + switch ($name) { + case "h1": + case "h2": + case "h3": + case "h4": + case "h5": + case "h6": + case "pre": + case "p": + // add two lines + $output .= "\n\n"; + break; + + case "br": + // add one line + $output .= "\n"; + break; + + case "div": + break; + + case "a": + // links are returned in [text](link) format + // @phpstan-ignore-next-line + $href = $node->getAttribute("href"); + + $output = trim($output); + + // remove double [[ ]] s from linking images + if (substr($output, 0, 1) == "[" && substr($output, -1) == "]") { + $output = substr($output, 1, strlen($output) - 2); + + // for linking images, the title of the <a> overrides the title of the <img> + // @phpstan-ignore-next-line + if ($node->getAttribute("title")) { + // @phpstan-ignore-next-line + $output = $node->getAttribute("title"); + } + } + + // if there is no link text, but a title attr + // @phpstan-ignore-next-line + if (!$output && $node->getAttribute("title")) { + // @phpstan-ignore-next-line + $output = $node->getAttribute("title"); + } + + if ($href == null) { + // it doesn't link anywhere + // @phpstan-ignore-next-line + if ($node->getAttribute("name") != null) { + if ($options['drop_links']) { + $output = "$output"; + } else { + $output = "[$output]"; + } + } + } else { + if ($href == $output || $href == "mailto:$output" || $href == "http://$output" || $href == "https://$output") { + // link to the same address: just use link + $output = "$output"; + } else { + // replace it + if ($output) { + if ($options['drop_links']) { + $output = "$output"; + } else { + $output = "[$output]($href)"; + } + } else { + // empty string + $output = "$href"; + } + } + } + + // does the next node require additional whitespace? + switch ($nextName) { + case "h1": case "h2": case "h3": case "h4": case "h5": case "h6": + $output .= "\n"; + break; + } + break; + + case "img": + // @phpstan-ignore-next-line + if ($node->getAttribute("title")) { + // @phpstan-ignore-next-line + $output = "[" . $node->getAttribute("title") . "]"; + // @phpstan-ignore-next-line + } elseif ($node->getAttribute("alt")) { + // @phpstan-ignore-next-line + $output = "[" . $node->getAttribute("alt") . "]"; + } else { + $output = ""; + } + break; + + case "li": + $output .= "\n"; + break; + + case "blockquote": + // process quoted text for whitespace/newlines + $output = self::processWhitespaceNewlines($output); + + // add leading newline + $output = "\n" . $output; + + // prepend '> ' at the beginning of all lines + $output = preg_replace("/\n/im", "\n> ", $output); + + // replace leading '> >' with '>>' + $output = preg_replace("/\n> >/im", "\n>>", $output); + + // add another leading newline and trailing newlines + $output = "\n" . $output . "\n\n"; + break; + default: + // do nothing + } + + return $output; + } +} |