/*
 * InspIRCd -- Internet Relay Chat Daemon
 *
 *   Copyright (C) 2022-2023 Sadie Powell <sadie@witchery.services>
 *
 * This file is part of InspIRCd.  InspIRCd is free software: you can
 * redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation, version 2.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */


/// $CompilerFlags: find_compiler_flags("libpcre2-8")
/// $LinkerFlags: find_linker_flags("libpcre2-8")

/// $PackageInfo: require_system("arch") pcre2
/// $PackageInfo: require_system("centos") pcre2-devel
/// $PackageInfo: require_system("darwin") pcre2
/// $PackageInfo: require_system("debian") libpcre2-dev
/// $PackageInfo: require_system("rocky") pcre2-devel
/// $PackageInfo: require_system("ubuntu") libpcre2-dev


#include "inspircd.h"
#include "modules/regex.h"

#define PCRE2_CODE_UNIT_WIDTH 8
#include <pcre2.h>

#ifdef _WIN32
# pragma comment(lib, "pcre2-8.lib")
#endif

class PCRE2Regex CXX11_FINAL
	: public Regex
{
 private:
	pcre2_code* regex;

 public:
	PCRE2Regex(const std::string& pattern)
		: Regex(pattern)
	{
		int errorcode;
		PCRE2_SIZE erroroffset;
		regex = pcre2_compile(reinterpret_cast<PCRE2_SPTR8>(pattern.c_str()), pattern.length(), 0, &errorcode, &erroroffset, NULL);
		if (!regex)
		{
			PCRE2_UCHAR errorstr[128];
			pcre2_get_error_message(errorcode, errorstr, sizeof errorstr);
			throw RegexException(pattern, reinterpret_cast<const char*>(errorstr), erroroffset);
		}
	}

	~PCRE2Regex() CXX11_OVERRIDE
	{
		pcre2_code_free(regex);
	}

	bool Matches(const std::string& text) CXX11_OVERRIDE
	{
		pcre2_match_data* unused = pcre2_match_data_create(1, NULL);
		int result = pcre2_match(regex, reinterpret_cast<PCRE2_SPTR8>(text.c_str()), text.length(), 0, 0, unused, NULL);
		pcre2_match_data_free(unused);
		return result >= 0;
	}
};

class PCRE2Factory CXX11_FINAL
	: public RegexFactory
{
 public:
	PCRE2Factory(Module* Creator)
		: RegexFactory(Creator, "regex/pcre")
	{
	}

	Regex* Create(const std::string& pattern) CXX11_OVERRIDE
	{
		return new PCRE2Regex(pattern);
	}
};

class ModuleRegexPCRE2 CXX11_FINAL
	: public Module
{
 private:
	PCRE2Factory regex;

 public:
	ModuleRegexPCRE2()
		: regex(this)
	{
	}

	Version GetVersion() CXX11_OVERRIDE
	{
		return Version("Provides the pcre regular expression engine which uses the PCRE2 library.");
	}
};

MODULE_INIT(ModuleRegexPCRE2)