/*
 *  Copyright (C) 1999-2001, 2004 Harri Porten (porten@kde.org)
 *  Copyright (c) 2007, 2008, 2016 Apple Inc. All rights reserved.
 *  Copyright (C) 2009 Torch Mobile, Inc.
 *  Copyright (C) 2010 Peter Varga (pvarga@inf.u-szeged.hu), University of Szeged
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; either
 *  version 2 of the License, or (at your option) any later version.
 *
 *  This library 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
 *  Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
 *
 */

#pragma once

#include "RegExp.h"
#include "JSCInlines.h"
#include "Yarr.h"
#include "YarrInterpreter.h"
#include "YarrJIT.h"
#include "YarrMatchingContextHolder.h"

#define REGEXP_FUNC_TEST_DATA_GEN 0

#if REGEXP_FUNC_TEST_DATA_GEN
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#endif

WTF_ALLOW_UNSAFE_BUFFER_USAGE_BEGIN

namespace JSC {

#if REGEXP_FUNC_TEST_DATA_GEN
class RegExpFunctionalTestCollector {
    // This class is not thread safe.
protected:
    static const char* const s_fileName;

public:
    static RegExpFunctionalTestCollector* get();

    ~RegExpFunctionalTestCollector();

    void outputOneTest(RegExp*, StringView, int, int*, int);
    void clearRegExp(RegExp* regExp)
    {
        if (regExp == m_lastRegExp)
            m_lastRegExp = 0;
    }

private:
    RegExpFunctionalTestCollector();

    void outputEscapedString(StringView, bool escapeSlash = false);

    static RegExpFunctionalTestCollector* s_instance;
    FILE* m_file;
    RegExp* m_lastRegExp;
};
#endif // REGEXP_FUNC_TEST_DATA_GEN

inline Structure* RegExp::createStructure(VM& vm, JSGlobalObject* globalObject, JSValue prototype)
{
    return Structure::create(vm, globalObject, prototype, TypeInfo(CellType, StructureFlags), info());
}

ALWAYS_INLINE bool RegExp::hasCodeFor(Yarr::CharSize charSize)
{
    if (hasCode()) {
#if ENABLE(YARR_JIT)
        if (m_state != JITCode)
            return true;
        ASSERT(m_regExpJITCode);
        if ((charSize == Yarr::CharSize::Char8) && (m_regExpJITCode->has8BitCode()))
            return true;
        if ((charSize == Yarr::CharSize::Char16) && (m_regExpJITCode->has16BitCode()))
            return true;
#else
        UNUSED_PARAM(charSize);
        return true;
#endif
    }
    return false;
}

ALWAYS_INLINE void RegExp::compileIfNecessary(VM& vm, Yarr::CharSize charSize, std::optional<StringView> sampleString)
{
    if (hasCodeFor(charSize))
        return;

    if (m_state == ParseError)
        return;

    compile(&vm, charSize, sampleString);
}

template<typename VectorType, Yarr::MatchFrom matchFrom>
ALWAYS_INLINE int RegExp::matchInline(JSGlobalObject* nullOrGlobalObject, VM& vm, StringView s, unsigned startOffset, VectorType& ovector)
{
#if ENABLE(REGEXP_TRACING)
    m_rtMatchCallCount++;
    m_rtMatchTotalSubjectStringLen += (double)(s.length() - startOffset);
#endif

    compileIfNecessary(vm, s.is8Bit() ? Yarr::CharSize::Char8 : Yarr::CharSize::Char16, s);

    auto throwError = [&] {
        if (matchFrom == Yarr::MatchFrom::CompilerThread)
            return -1;
        if (nullOrGlobalObject) {
            auto throwScope = DECLARE_THROW_SCOPE(vm);
            throwScope.throwException(nullOrGlobalObject, errorToThrow(nullOrGlobalObject));
        }
        if (!hasHardError(m_constructionErrorCode))
            reset();
        return -1;
    };

    if (m_state == ParseError)
        return throwError();

    ovector.resize(offsetVectorSize());
    int* offsetVector = ovector.data();

    if constexpr (matchFrom == Yarr::MatchFrom::VMThread) {
        if (hasValidAtom()) {
            size_t found = s.find(vm.adaptiveStringSearcherTables(), atom(), startOffset);
            if (found == notFound)
                return -1;
            offsetVector[0] = found;
            offsetVector[1] = found + atom().length();
            return found;
        }
    }

    int result;
#if ENABLE(YARR_JIT)
    if (m_state == JITCode) {
        {
            ASSERT(m_regExpJITCode);
            Yarr::MatchingContextHolder regExpContext(vm, m_regExpJITCode->usesPatternContextBuffer(), this, matchFrom);

            if (s.is8Bit())
                result = m_regExpJITCode->execute(s.span8(), startOffset, offsetVector, &regExpContext).start;
            else
                result = m_regExpJITCode->execute(s.span16(), startOffset, offsetVector, &regExpContext).start;
        }

        if (result == static_cast<int>(Yarr::JSRegExpResult::JITCodeFailure)) {
            // JIT'ed code couldn't handle expression, so punt back to the interpreter.
            byteCodeCompileIfNecessary(&vm);
            if (m_state == ParseError)
                return throwError();
            {
                constexpr bool usesPatternContextBuffer = false;
                Yarr::MatchingContextHolder regExpContext(vm, usesPatternContextBuffer, this, matchFrom);
                result = Yarr::interpret(m_regExpBytecode.get(), s, startOffset, reinterpret_cast<unsigned*>(offsetVector));
            }
        }

#if ENABLE(YARR_JIT_DEBUG)
        if (m_state == JITCode) {
            byteCodeCompileIfNecessary(&vm);
            if (m_state == ParseError)
                return throwError();
            matchCompareWithInterpreter(s, startOffset, offsetVector, result);
        }
#endif
    } else
#endif
    {
        constexpr bool usesPatternContextBuffer = false;
        Yarr::MatchingContextHolder regExpContext(vm, usesPatternContextBuffer, this, matchFrom);
        result = Yarr::interpret(m_regExpBytecode.get(), s, startOffset, reinterpret_cast<unsigned*>(offsetVector));
    }

    ASSERT(result >= -1);

#if REGEXP_FUNC_TEST_DATA_GEN
    RegExpFunctionalTestCollector::get()->outputOneTest(this, s, startOffset, offsetVector, result);
#endif

#if ENABLE(REGEXP_TRACING)
    if (result != -1)
        m_rtMatchFoundCount++;
#endif

    return result;
}

ALWAYS_INLINE bool RegExp::hasMatchOnlyCodeFor(Yarr::CharSize charSize)
{
    if (hasCode()) {
#if ENABLE(YARR_JIT)
        if (m_state != JITCode)
            return true;
        ASSERT(m_regExpJITCode);
        if ((charSize == Yarr::CharSize::Char8) && (m_regExpJITCode->has8BitCodeMatchOnly()))
            return true;
        if ((charSize == Yarr::CharSize::Char16) && (m_regExpJITCode->has16BitCodeMatchOnly()))
            return true;
#else
        UNUSED_PARAM(charSize);
        return true;
#endif
    }

    return false;
}

ALWAYS_INLINE void RegExp::compileIfNecessaryMatchOnly(VM& vm, Yarr::CharSize charSize, std::optional<StringView> sampleString)
{
    if (hasMatchOnlyCodeFor(charSize))
        return;

    if (m_state == ParseError)
        return;

    compileMatchOnly(&vm, charSize, sampleString);
}

template<Yarr::MatchFrom matchFrom>
ALWAYS_INLINE MatchResult RegExp::matchInline(JSGlobalObject* nullOrGlobalObject, VM& vm, StringView s, unsigned startOffset)
{
#if ENABLE(REGEXP_TRACING)
    m_rtMatchOnlyCallCount++;
    m_rtMatchOnlyTotalSubjectStringLen += (double)(s.length() - startOffset);
#endif

    compileIfNecessaryMatchOnly(vm, s.is8Bit() ? Yarr::CharSize::Char8 : Yarr::CharSize::Char16, s);

    auto throwError = [&] {
        if (matchFrom == Yarr::MatchFrom::CompilerThread)
            return MatchResult::failed();
        if (nullOrGlobalObject) {
            auto throwScope = DECLARE_THROW_SCOPE(vm);
            throwScope.throwException(nullOrGlobalObject, errorToThrow(nullOrGlobalObject));
        }
        if (!hasHardError(m_constructionErrorCode))
            reset();
        return MatchResult::failed();
    };

    if (m_state == ParseError)
        return throwError();

    if constexpr (matchFrom == Yarr::MatchFrom::VMThread) {
        if (hasValidAtom()) {
            size_t found = StringView(s).find(vm.adaptiveStringSearcherTables(), atom(), startOffset);
            if (found == notFound)
                return MatchResult::failed();
            return MatchResult { found, found + atom().length() };
        }
    }

#if ENABLE(YARR_JIT)
    if (m_state == JITCode) {
        MatchResult result;
        {
            ASSERT(m_regExpJITCode);
            Yarr::MatchingContextHolder regExpContext(vm, m_regExpJITCode->usesPatternContextBuffer(), this, matchFrom);

            if (s.is8Bit())
                result = m_regExpJITCode->execute(s.span8(), startOffset, &regExpContext);
            else
                result = m_regExpJITCode->execute(s.span16(), startOffset, &regExpContext);
        }

#if ENABLE(REGEXP_TRACING)
        if (!result)
            m_rtMatchOnlyFoundCount++;
#endif
        if (result.start != static_cast<size_t>(Yarr::JSRegExpResult::JITCodeFailure))
            return result;

        // JIT'ed code couldn't handle expression, so punt back to the interpreter.
        byteCodeCompileIfNecessary(&vm);
        if (m_state == ParseError)
            return throwError();
    }
#endif

    int* offsetVector;
    int result;
    Vector<int, 32> nonReturnedOvector;
    nonReturnedOvector.grow(offsetVectorSize());
    offsetVector = nonReturnedOvector.data();
    {
        constexpr bool usesPatternContextBuffer = false;
        Yarr::MatchingContextHolder regExpContext(vm, usesPatternContextBuffer, this, matchFrom);
        result = Yarr::interpret(m_regExpBytecode.get(), s, startOffset, reinterpret_cast<unsigned*>(offsetVector));
    }
#if REGEXP_FUNC_TEST_DATA_GEN
    RegExpFunctionalTestCollector::get()->outputOneTest(this, s, startOffset, offsetVector, result);
#endif

    if (result >= 0) {
#if ENABLE(REGEXP_TRACING)
        m_rtMatchOnlyFoundCount++;
#endif
        return MatchResult(result, reinterpret_cast<unsigned*>(offsetVector)[1]);
    }

    return MatchResult::failed();
}

} // namespace JSC

WTF_ALLOW_UNSAFE_BUFFER_USAGE_END