* @license GNU General Public License 2.0
*/
class AutoP
{
// 作为段落的标签
private const BLOCK = 'p|pre|div|blockquote|form|ul|ol|dd|table|ins|h1|h2|h3|h4|h5|h6';
/**
* 唯一id
*
* @access private
* @var integer
*/
private $uniqueId = 0;
/**
* 存储的段落
*
* @access private
* @var array
*/
private $blocks = [];
/**
* 替换段落的回调函数
*
* @param array $matches 匹配值
* @return string
*/
public function replaceBlockCallback(array $matches): string
{
$tagMatch = '|' . $matches[1] . '|';
$text = $matches[4];
switch (true) {
/** 用br处理换行 */
case false !== strpos(
'|li|dd|dt|td|p|a|span|cite|strong|sup|sub|small|del|u|i|b|ins|h1|h2|h3|h4|h5|h6|',
$tagMatch
):
$text = nl2br(trim($text));
break;
/** 用段落处理换行 */
case false !== strpos('|div|blockquote|form|', $tagMatch):
$text = $this->cutByBlock($text);
if (false !== strpos($text, '')) {
$text = $this->fixParagraph($text);
}
break;
default:
break;
}
/** 没有段落能力的标签 */
if (false !== strpos('|a|span|font|code|cite|strong|sup|sub|small|del|u|i|b|', $tagMatch)) {
$key = '';
} else {
$key = '';
}
$this->blocks[$key] = "<{$matches[1]}{$matches[3]}>{$text}";
return $key;
}
/**
* 用段落方法处理换行
*
* @param string $text
* @return string
*/
private function cutByBlock(string $text): string
{
$space = "( | )";
$text = str_replace("\r\n", "\n", trim($text));
$text = preg_replace("/{$space}*\n{$space}*/is", "\n", $text);
$text = preg_replace("/\s*\s*/is", "
", $text);
$text = preg_replace("/\n{2,}/", "
", $text);
$text = nl2br($text);
$text = preg_replace("/(
)?\s*\s*(<\/p>)?/is", "", $text);
$text = preg_replace("/
{$space}*<\/p>/is", '', $text);
$text = preg_replace("/\s*
\s*$/is", '', $text);
$text = preg_replace("/^\s*<\/p>\s*/is", '', $text);
return $text;
}
/**
* 修复段落开头和结尾
*
* @param string $text
* @return string
*/
private function fixParagraph(string $text): string
{
$text = trim($text);
if (!preg_match("/^<(" . self::BLOCK . ")(\s|>)/i", $text)) {
$text = '
' . $text;
}
if (!preg_match("/<\/(" . self::BLOCK . ")>$/i", $text)) {
$text = $text . '
';
}
return $text;
}
/**
* 自动分段
*
* @param string $text
* @return string
*/
public function parse(string $text): string
{
/** 重置计数器 */
$this->uniqueId = 0;
$this->blocks = [];
/** 将已有的段落后面的换行处理掉 */
$text = preg_replace(["/<\/p>\s+\s*/is"], [""], trim($text));
/** 将所有非自闭合标签解析为唯一的字符串 */
$foundTagCount = 0;
$textLength = strlen($text);
$uniqueIdList = [];
if (preg_match_all("/<\/\s*([a-z0-9]+)>/is", $text, $matches, PREG_OFFSET_CAPTURE)) {
foreach ($matches[0] as $key => $match) {
$tag = $matches[1][$key][0];
$leftOffset = $match[1] - $textLength;
$posSingle = strrpos($text, '<' . $tag . '>', $leftOffset);
$posFix = strrpos($text, '<' . $tag . ' ', $leftOffset);
$pos = false;
switch (true) {
case (false !== $posSingle && false !== $posFix):
$pos = max($posSingle, $posFix);
break;
case false === $posSingle && false !== $posFix:
$pos = $posFix;
break;
case false !== $posSingle && false === $posFix:
$pos = $posSingle;
break;
default:
break;
}
if (false !== $pos) {
$uniqueId = $this->makeUniqueId();
$uniqueIdList[$uniqueId] = $tag;
$tagLength = strlen($tag);
$text = substr_replace($text, $uniqueId, $pos + 1 + $tagLength, 0);
$text = substr_replace(
$text,
$uniqueId,
$match[1] + 7 + $foundTagCount * 10 + $tagLength,
0
); // 7 = 5 + 2
$foundTagCount++;
}
}
}
foreach ($uniqueIdList as $uniqueId => $tag) {
$text = preg_replace_callback(
"/<({$tag})({$uniqueId})([^>]*)>(.*)<\/\\1\\2>/is",
[$this, 'replaceBlockCallback'],
$text,
1
);
}
$text = $this->cutByBlock($text);
$blocks = array_reverse($this->blocks);
foreach ($blocks as $blockKey => $blockValue) {
$text = str_replace($blockKey, $blockValue, $text);
}
return $this->fixParagraph($text);
}
/**
* 生成唯一的id, 为了速度考虑最多支持1万个tag的处理
*
* @return string
*/
private function makeUniqueId(): string
{
return ':' . str_pad($this->uniqueId ++, 4, '0', STR_PAD_LEFT);
}
}