/* m_this file is part of the KDE libraries
    Copyright (C) 2020 Tomaz Cananbrava (tcanabrava@kde.org)
    Copyright (c) 2003 Cornelius Schumacher <schumacher@kde.org>
    Copyright (c) 2003 Waldo Bastian <bastian@kde.org>
    Copyright (c) 2003 Zack Rusin <zack@kde.org>
    Copyright (c) 2006 Michaël Larouche <michael.larouche@kdemail.net>
    Copyright (c) 2008 Allen Winter <winter@kde.org>
    Copyright (C) 2020 Tomaz Cananbrava (tcanabrava@kde.org)

    m_this library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Library General Public
    License as published by the Free Software Foundation; either
    version 2 of the License, or (at your option) any later version.

    m_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
    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public License
    along with this library; see the file COPYING.LIB.  If not, write to
    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
    Boston, MA 02110-1301, USA.
*/

#include "KConfigCodeGeneratorBase.h"
#include "KConfigParameters.h"
#include "KConfigCommonStructs.h"

#include <QTextStream>
#include <QLatin1Char>
#include <QFileInfo>

#include <ostream>
#include <QDebug>

using std::endl;

namespace
{
QTextStream cout(stdout);
QTextStream cerr(stderr);
}

KConfigCodeGeneratorBase::KConfigCodeGeneratorBase(
    const QString &inputFile,
    const QString &baseDir,
    const QString &fileName,
    const KConfigParameters &parameters,
    ParseResult &parseResult)
    : m_inputFile(inputFile), m_baseDir(baseDir), m_fileName(fileName), m_cfg(parameters), parseResult(parseResult)
{
    m_file.setFileName(m_fileName);
    if (!m_file.open(QIODevice::WriteOnly)) {
        cerr << "Can not open '" << m_fileName << "for writing." << endl;
        exit(1);
    }
    m_stream.setDevice(&m_file);
    m_stream.setCodec("utf-8");

    if (m_cfg.staticAccessors) {
        m_this = QStringLiteral("self()->");
    } else {
        m_const = QStringLiteral(" const");
    }
}

KConfigCodeGeneratorBase::~KConfigCodeGeneratorBase()
{
    save();
}

void KConfigCodeGeneratorBase::save()
{
    m_file.close();
}

//TODO: Remove this weird logic and adapt the testcases
void KConfigCodeGeneratorBase::indent()
{
    if (m_indentLevel >= 4) {
        m_indentLevel += 2;
    } else {
        m_indentLevel += 4;
    }
}

void KConfigCodeGeneratorBase::unindent()
{
    if (m_indentLevel > 4) {
        m_indentLevel -= 2;
    } else {
        m_indentLevel -= 4;
    }
}

QString KConfigCodeGeneratorBase::whitespace() const
{
    QString spaces;
    for (int i = 0; i < m_indentLevel; i++) {
        spaces.append(QLatin1Char(' '));
    }
    return spaces;
}

void KConfigCodeGeneratorBase::startScope()
{
    m_stream << whitespace() << QLatin1Char('{');
    m_stream << endl;
    indent();
}

void KConfigCodeGeneratorBase::endScope(ScopeFinalizer finalizer)
{
    unindent();
    m_stream << whitespace() << QLatin1Char('}');
    if (finalizer == ScopeFinalizer::Semicolon) {
        m_stream << ';';
    }
    m_stream << endl;
}

void KConfigCodeGeneratorBase::start()
{
    const QString m_fileName = QFileInfo(m_inputFile).fileName();
    m_stream << "// This file is generated by kconfig_compiler_kf5 from " << m_fileName << ".kcfg" << "." << endl;
    m_stream << "// All changes you do to this file will be lost." << endl;
}

void KConfigCodeGeneratorBase::addHeaders(const QStringList &headerList)
{
    for (auto include : qAsConst(headerList)) {
        if (include.startsWith(QLatin1Char('"'))) {
            m_stream << "#include " << include << endl;
        } else {
            m_stream << "#include <" << include << ">" << endl;
        }
    }
}

// adds as many 'namespace foo {' lines to p_out as
// there are namespaces in p_ns
void KConfigCodeGeneratorBase::beginNamespaces()
{
    if (!m_cfg.nameSpace.isEmpty()) {
        for (const QString &ns : m_cfg.nameSpace.split(QStringLiteral("::"))) {
            m_stream << "namespace " << ns << " {" << endl;
        }
        m_stream << endl;
    }
}

// adds as many '}' lines to p_out as
// there are namespaces in p_ns
void KConfigCodeGeneratorBase::endNamespaces()
{
    if (!m_cfg.nameSpace.isEmpty()) {
        m_stream << endl;
        const int namespaceCount = m_cfg.nameSpace.count(QStringLiteral("::")) + 1;
        for (int i = 0; i < namespaceCount; ++i) {
            m_stream << "}" << endl;
        }
    }
}

// returns the member accesor implementation
// which should go in the h file if inline
// or the cpp file if not inline
QString KConfigCodeGeneratorBase::memberAccessorBody(const CfgEntry *e, bool globalEnums) const
{
    QString result;
    QTextStream out(&result, QIODevice::WriteOnly);
    QString n = e->name;
    QString t = e->type;
    bool useEnumType = m_cfg.useEnumTypes && t == QLatin1String("Enum");

    out << "return ";
    if (useEnumType) {
        out << "static_cast<" << enumType(e, globalEnums) << ">(";
    }
    out << m_this << varPath(n, m_cfg);
    if (!e->param.isEmpty()) {
        out << "[i]";
    }
    if (useEnumType) {
        out << ")";
    }
    out << ";" << endl;

    return result;
}

void KConfigCodeGeneratorBase::createIfSetLogic(const CfgEntry *e, const QString &varExpression)
{
    const QString n = e->name;
    const QString t = e->type;
    const bool hasBody = !e->signalList.empty() || m_cfg.generateProperties;

    m_stream << whitespace() << "if (";
    if (hasBody) {
        m_stream << "v != " << varExpression << " && ";
    }
    m_stream << "!" << m_this << "isImmutable( QStringLiteral( \"";
    if (!e->param.isEmpty()) {
        QString paramName = e->paramName;

        m_stream << paramName.replace(QStringLiteral("$(") + e->param + QStringLiteral(")"), QLatin1String("%1")) << "\" ).arg( ";
        if (e->paramType == QLatin1String("Enum")) {
            m_stream << "QLatin1String( ";

            if (m_cfg.globalEnums) {
                m_stream << enumName(e->param) << "ToString[i]";
            } else {
                m_stream << enumName(e->param) << "::enumToString[i]";
            }

            m_stream << " )";
        } else {
            m_stream << "i";
        }
        m_stream << " )";
    } else {
        m_stream << n << "\" )";
    }
    m_stream << " ))";
}

void KConfigCodeGeneratorBase::memberMutatorBody(const CfgEntry *e)
{
    QString n = e->name;
    QString t = e->type;

    // HACK: Don't open '{' manually, use startScope / endScope to automatically handle whitespace indentation.
    if (!e->min.isEmpty()) {
        if (e->min != QLatin1String("0") || !isUnsigned(t)) { // skip writing "if uint<0" (#187579)
            m_stream << whitespace() << "if (v < " << e->min << ")" << endl;
            m_stream << whitespace() << "{" << endl;
            m_stream << whitespace(); addDebugMethod(m_stream, m_cfg, n);
            m_stream << ": value \" << v << \" is less than the minimum value of " << e->min << "\";" << endl;
            m_stream << whitespace() << "  v = " << e->min << ";" << endl;
            m_stream << whitespace() << "}" << endl;
        }
    }

    if (!e->max.isEmpty()) {
        m_stream << endl;
        m_stream << whitespace() << "if (v > " << e->max << ")" << endl;
        m_stream << whitespace() << "{" << endl;
        m_stream << whitespace(); addDebugMethod(m_stream, m_cfg, n);
        m_stream << ": value \" << v << \" is greater than the maximum value of " << e->max << "\";" << endl;
        m_stream << whitespace() << "  v = " << e->max << ";" << endl;
        m_stream << whitespace() << "}" << endl << endl;
    }

    const QString varExpression = m_this + varPath(n, m_cfg) + (e->param.isEmpty() ? QString() : QStringLiteral("[i]"));

    // TODO: Remove this `hasBody` logic, always use an '{' for the if.
    const bool hasBody = !e->signalList.empty() || m_cfg.generateProperties;

    // m_this call creates an `if (someTest ...) that's just to long to throw over the code.
    createIfSetLogic(e, varExpression);
    m_stream << (hasBody ? " {" : "") << endl;
    m_stream << whitespace() << "  " << varExpression << " = v;" << endl;

    const auto listSignal = e->signalList;
    for (const Signal &signal : qAsConst(listSignal)) {
        if (signal.modify) {
            m_stream << whitespace() << "  Q_EMIT " << m_this << signal.name << "();" << endl;
        } else {
            m_stream << whitespace() <<  "  " << m_this << varPath(QStringLiteral("settingsChanged"), m_cfg)
                << " |= " << signalEnumName(signal.name) << ";" << endl;
        }
    }
    if (hasBody) {
        m_stream << whitespace() << "}" << endl;
    }
}