1 files changed, 199 insertions, 0 deletions
diff --git a/phpBB/phpbb/textformatter/s9e/bbcode_merger.php b/phpBB/phpbb/textformatter/s9e/bbcode_merger.php
new file mode 100644
index 0000000000..264eb93782
--- /dev/null
+++ b/phpBB/phpbb/textformatter/s9e/bbcode_merger.php
@@ -0,0 +1,199 @@
+<?php
+/**
+*
+* This file is part of the phpBB Forum Software package.
+*
+* @copyright (c) phpBB Limited <https://www.phpbb.com>
+* @license GNU General Public License, version 2 (GPL-2.0)
+*
+* For full copyright and license information, please see
+* the docs/CREDITS.txt file.
+*
+*/
+
+namespace phpbb\textformatter\s9e;
+
+use phpbb\textformatter\s9e\factory;
+use s9e\TextFormatter\Configurator\Helpers\TemplateHelper;
+use s9e\TextFormatter\Configurator\Items\UnsafeTemplate;
+
+class bbcode_merger
+{
+	/**
+	* @var \s9e\TextFormatter\Configurator $configurator Configurator instance used to inspect BBCodes
+	*/
+	protected $configurator;
+
+	/**
+	* @param \phpbb\textformatter\s9e\factory $factory
+	*/
+	public function __construct(factory $factory)
+	{
+		$this->configurator = $factory->get_configurator();
+	}
+
+	/**
+	* Merge two BBCode definitions
+	*
+	* All of the arrays contain a "usage" element and a "template" element
+	*
+	* @throws InvalidArgumentException if a definition cannot be interpreted
+	* @throws RuntimeException if something unexpected occurs
+	*
+	* @param  array $without BBCode definition without an attribute
+	* @param  array $with    BBCode definition with an attribute
+	* @return array          Merged definition
+	*/
+	public function merge_bbcodes(array $without, array $with)
+	{
+		$without = $this->create_bbcode($without);
+		$with    = $this->create_bbcode($with);
+
+		// Select the appropriate strategy for merging this BBCode
+		if (!$this->is_optional_bbcode($without, $with) && $this->is_content_bbcode($without, $with))
+		{
+			$merged = $this->merge_content_bbcode($without, $with);
+		}
+		else
+		{
+			$merged = $this->merge_optional_bbcode($without, $with);
+		}
+
+		$merged['template'] = $this->normalize_template($merged['template']);
+
+		return $merged;
+	}
+
+	/**
+	* Create a custom BBCode for inspection
+	*
+	* @param  array $definition Original BBCode definition
+	* @return array             Updated definition containing a BBCode object and a Tag
+	*/
+	protected function create_bbcode(array $definition)
+	{
+		$bbcode = $this->configurator->BBCodes->addCustom(
+			$definition['usage'],
+			new UnsafeTemplate($definition['template'])
+		);
+
+		$definition['bbcode'] = $bbcode;
+		$definition['tag']    = $this->configurator->tags[$bbcode->tagName];
+
+		return $definition;
+	}
+
+	/**
+	* Indent given template for readability
+	*
+	* @param  string $template
+	* @return string
+	*/
+	protected function indent_template($template)
+	{
+		$dom = TemplateHelper::loadTemplate($template);
+		$dom->formatOutput = true;
+		$template = TemplateHelper::saveTemplate($dom);
+
+		// Remove the first level of indentation if the template starts with whitespace
+		if (preg_match('(^\\n +)', $template, $m))
+		{
+			$template = str_replace($m[0], "\n", $template);
+		}
+
+		return trim($template);
+	}
+
+	/**
+	* Test whether the two definitions form a "content"-style BBCode
+	*
+	* Such BBCodes include the [url] BBCode, which uses its text content as
+	* attribute if none is provided
+	*
+	* @param  array $without BBCode definition without an attribute
+	* @param  array $with    BBCode definition with an attribute
+	* @return bool
+	*/
+	protected function is_content_bbcode(array $without, array $with)
+	{
+		// Test whether we find the same non-TEXT token between "]" and "[" in the usage
+		// as between ">" and "<" in the template
+		return (preg_match('(\\]\\s*(\\{(?!TEXT)[^}]+\\})\\s*\\[)', $without['usage'], $m)
+			&& preg_match('(>[^<]*?' . preg_quote($m[1]) . '[^>]*?<)s', $without['template']));
+	}
+
+	/**
+	* Test whether the two definitions form BBCode with an optional attribute
+	*
+	* @param  array $without BBCode definition without an attribute
+	* @param  array $with    BBCode definition with an attribute
+	* @return bool
+	*/
+	protected function is_optional_bbcode(array $without, array $with)
+	{
+		// Remove the default attribute from the definition
+		$with['usage'] = preg_replace('(=[^\\]]++)', '', $with['usage']);
+
+		// Test whether both definitions are the same, regardless of case
+		return strcasecmp($without['usage'], $with['usage']) === 0;
+	}
+
+	/**
+	* Merge the two BBCode definitions of a "content"-style BBCode
+	*
+	* @param  array $without BBCode definition without an attribute
+	* @param  array $with    BBCode definition with an attribute
+	* @return array          Merged definition
+	*/
+	protected function merge_content_bbcode(array $without, array $with)
+	{
+		// Convert [x={X}] into [x={X;useContent}]
+		$usage = preg_replace('(\\})', ';useContent}', $with['usage'], 1);
+
+		// Use the template from the definition that uses an attribute
+		$template = $with['tag']->template;
+
+		return ['usage' => $usage, 'template' => $template];
+	}
+
+	/**
+	* Merge the two BBCode definitions of a BBCode with an optional argument
+	*
+	* Such BBCodes include the [quote] BBCode, which takes an optional argument
+	* but otherwise does not behave differently
+	*
+	* @param  array $without BBCode definition without an attribute
+	* @param  array $with    BBCode definition with an attribute
+	* @return array          Merged definition
+	*/
+	protected function merge_optional_bbcode(array $without, array $with)
+	{
+		// Convert [X={X}] into [X={X?}]
+		$usage = preg_replace('(\\})', '?}', $with['usage'], 1);
+
+		// Build a template for both versions
+		$template = '<xsl:choose><xsl:when test="@' . $with['bbcode']->defaultAttribute . '">' . $with['tag']->template . '</xsl:when><xsl:otherwise>' . $without['tag']->template . '</xsl:otherwise></xsl:choose>';
+
+		return ['usage' => $usage, 'template' => $template];
+	}
+
+	/**
+	* Normalize a template
+	*
+	* @param  string $template
+	* @return string
+	*/
+	protected function normalize_template($template)
+	{
+		// Normalize the template to simplify it
+		$template = $this->configurator->templateNormalizer->normalizeTemplate($template);
+
+		// Convert xsl:value-of elements back to {L_} tokens where applicable
+		$template = preg_replace('(<xsl:value-of select="\\$(L_\\w+)"/>)', '{$1}', $template);
+
+		// Beautify the template
+		$template = $this->indent_template($template);
+
+		return $template;
+	}
+}