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#include "fileutils.h"
#include "savefile.h"

#include "qtcassert.h"

#include <QtCore/QDir>
#include <QtCore/QFileInfo>
#include <QtCore/QTemporaryFile>
#include <QtCore/QDateTime>
#include <QtCore/QDataStream>
#include <QtCore/QTextStream>
#include <QtGui/QMessageBox>

namespace Utils {

/*! \class Utils::FileUtils

  \brief File- and directory-related convenience functions.

  File- and directory-related convenience functions.
*/

/*!
  Removes the directory \a filePath and its subdirectories recursively.

  \note The \a error parameter is optional.

  \return Whether the operation succeeded.
*/
bool FileUtils::removeRecursively(const QString &filePath, QString *error)
{
    QFileInfo fileInfo(filePath);
    if (!fileInfo.exists())
        return true;
    QFile::setPermissions(filePath, fileInfo.permissions() | QFile::WriteUser);
    if (fileInfo.isDir()) {
        QDir dir(filePath);
        dir = dir.canonicalPath();
        if (dir.isRoot()) {
            if (error) {
                *error = QCoreApplication::translate("Utils::FileUtils",
                    "Refusing to remove root directory.");
            }
            return false;
        }
        if (dir.path() == QDir::home().canonicalPath()) {
            if (error) {
                *error = QCoreApplication::translate("Utils::FileUtils",
                    "Refusing to remove your home directory.");
            }
            return false;
        }

        QStringList fileNames = dir.entryList(QDir::Files | QDir::Hidden
                                              | QDir::System | QDir::Dirs | QDir::NoDotAndDotDot);
        foreach (const QString &fileName, fileNames) {
            if (!removeRecursively(filePath + QLatin1Char('/') + fileName, error))
                return false;
        }
        if (!QDir::root().rmdir(dir.path())) {
            if (error) {
                *error = QCoreApplication::translate("Utils::FileUtils", "Failed to remove directory '%1'.")
                        .arg(QDir::toNativeSeparators(filePath));
            }
            return false;
        }
    } else {
        if (!QFile::remove(filePath)) {
            if (error) {
                *error = QCoreApplication::translate("Utils::FileUtils", "Failed to remove file '%1'.")
                        .arg(QDir::toNativeSeparators(filePath));
            }
            return false;
        }
    }
    return true;
}

/*!
  Copies the directory specified by \a srcFilePath recursively to \a tgtFilePath. \a tgtFilePath will contain
  the target directory, which will be created. Example usage:

  \code
    QString error;
    book ok = Utils::FileUtils::copyRecursively("/foo/bar", "/foo/baz", &error);
    if (!ok)
      qDebug() << error;
  \endcode

  This will copy the contents of /foo/bar into to the baz directory under /foo, which will be created in the process.

  \note The \a error parameter is optional.

  \return Whether the operation succeeded.
*/
bool FileUtils::copyRecursively(const QString &srcFilePath,
                     const QString &tgtFilePath, QString *error)
{
    QFileInfo srcFileInfo(srcFilePath);
    if (srcFileInfo.isDir()) {
        QDir targetDir(tgtFilePath);
        targetDir.cdUp();
        if (!targetDir.mkdir(QFileInfo(tgtFilePath).fileName())) {
            if (error) {
                *error = QCoreApplication::translate("Utils::FileUtils", "Failed to create directory '%1'.")
                        .arg(QDir::toNativeSeparators(tgtFilePath));
                return false;
            }
        }
        QDir sourceDir(srcFilePath);
        QStringList fileNames = sourceDir.entryList(QDir::Files | QDir::Dirs | QDir::NoDotAndDotDot | QDir::Hidden | QDir::System);
        foreach (const QString &fileName, fileNames) {
            const QString newSrcFilePath
                    = srcFilePath + QLatin1Char('/') + fileName;
            const QString newTgtFilePath
                    = tgtFilePath + QLatin1Char('/') + fileName;
            if (!copyRecursively(newSrcFilePath, newTgtFilePath, error))
                return false;
        }
    } else {
        if (!QFile::copy(srcFilePath, tgtFilePath)) {
            if (error) {
                *error = QCoreApplication::translate("Utils::FileUtils", "Could not copy file '%1' to '%2'.")
                        .arg(QDir::toNativeSeparators(srcFilePath),
                             QDir::toNativeSeparators(tgtFilePath));
            }
            return false;
        }
    }
    return true;
}

/*!
  If \a filePath is a directory, the function will recursively check all files and return
  true if one of them is newer than \a timeStamp. If \a filePath is a single file, true will
  be returned if the file is newer than \timeStamp.

  \return Whether at least one file in \a filePath has a newer date than \a timeStamp.
*/
bool FileUtils::isFileNewerThan(const QString &filePath,
    const QDateTime &timeStamp)
{
    QFileInfo fileInfo(filePath);
    if (!fileInfo.exists() || fileInfo.lastModified() >= timeStamp)
        return true;
    if (fileInfo.isDir()) {
        const QStringList dirContents = QDir(filePath)
            .entryList(QDir::Files | QDir::Dirs | QDir::NoDotAndDotDot);
        foreach (const QString &curFileName, dirContents) {
            const QString curFilePath
                = filePath + QLatin1Char('/') + curFileName;
            if (isFileNewerThan(curFilePath, timeStamp))
                return true;
        }
    }
    return false;
}

/*!
  Recursively resolve possibly present symlinks in \a filePath.
  Unlike QFileInfo::canonicalFilePath(), this function will still return the expected target file
  even if the symlink is dangling.

  \note Maximum recursion depth == 16.

  return Symlink target file path.
*/
QString FileUtils::resolveSymlinks(const QString &path)
{
    QFileInfo f(path);
    int links = 16;
    while (links-- && f.isSymLink())
        f.setFile(f.symLinkTarget());
    if (links <= 0)
        return QString();
    return f.filePath();
}


QByteArray FileReader::fetchQrc(const QString &fileName)
{
    QTC_ASSERT(fileName.startsWith(QLatin1Char(':')), return QByteArray())
    QFile file(fileName);
    bool ok = file.open(QIODevice::ReadOnly);
    QTC_ASSERT(ok, qWarning() << fileName << "not there!"; return QByteArray())
    return file.readAll();
}

bool FileReader::fetch(const QString &fileName, QIODevice::OpenMode mode)
{
    QTC_ASSERT(!(mode & ~(QIODevice::ReadOnly | QIODevice::Text)), return false)

    QFile file(fileName);
    if (!file.open(QIODevice::ReadOnly | mode)) {
        m_errorString = tr("Cannot open %1 for reading: %2").arg(
                QDir::toNativeSeparators(fileName), file.errorString());
        return false;
    }
    m_data = file.readAll();
    if (file.error() != QFile::NoError) {
        m_errorString = tr("Cannot read %1: %2").arg(
                QDir::toNativeSeparators(fileName), file.errorString());
        return false;
    }
    return true;
}

bool FileReader::fetch(const QString &fileName, QIODevice::OpenMode mode, QString *errorString)
{
    if (fetch(fileName, mode))
        return true;
    if (errorString)
        *errorString = m_errorString;
    return false;
}

bool FileReader::fetch(const QString &fileName, QIODevice::OpenMode mode, QWidget *parent)
{
    if (fetch(fileName, mode))
        return true;
    if (parent)
        QMessageBox::critical(parent, tr("File Error"), m_errorString);
    return false;
}


FileSaverBase::FileSaverBase()
    : m_hasError(false)
{
}

FileSaverBase::~FileSaverBase()
{
    delete m_file;
}

bool FileSaverBase::finalize()
{
    m_file->close();
    setResult(m_file->error() == QFile::NoError);
    // We delete the object, so it is really closed even if it is a QTemporaryFile.
    delete m_file;
    m_file = 0;
    return !m_hasError;
}

bool FileSaverBase::finalize(QString *errStr)
{
    if (finalize())
        return true;
    if (errStr)
        *errStr = errorString();
    return false;
}

bool FileSaverBase::finalize(QWidget *parent)
{
    if (finalize())
        return true;
    QMessageBox::critical(parent, tr("File Error"), errorString());
    return false;
}

bool FileSaverBase::write(const char *data, int len)
{
    if (m_hasError)
        return false;
    return setResult(m_file->write(data, len) == len);
}

bool FileSaverBase::write(const QByteArray &bytes)
{
    if (m_hasError)
        return false;
    return setResult(m_file->write(bytes) == bytes.count());
}

bool FileSaverBase::setResult(bool ok)
{
    if (!ok && !m_hasError) {
        m_errorString = tr("Cannot write file %1. Disk full?").arg(
                QDir::toNativeSeparators(m_fileName));
        m_hasError = true;
    }
    return ok;
}

bool FileSaverBase::setResult(QTextStream *stream)
{
#if QT_VERSION >= QT_VERSION_CHECK(4, 8, 0)
    stream->flush();
    return setResult(stream->status() == QTextStream::Ok);
#else
    Q_UNUSED(stream)
    return true;
#endif
}

bool FileSaverBase::setResult(QDataStream *stream)
{
#if QT_VERSION >= QT_VERSION_CHECK(4, 8, 0)
    return setResult(stream->status() == QDataStream::Ok);
#else
    Q_UNUSED(stream)
    return true;
#endif
}

bool FileSaverBase::setResult(QXmlStreamWriter *stream)
{
#if QT_VERSION >= QT_VERSION_CHECK(4, 8, 0)
    return setResult(!stream->hasError());
#else
    Q_UNUSED(stream)
    return true;
#endif
}


FileSaver::FileSaver(const QString &filename, QIODevice::OpenMode mode)
{
    m_fileName = filename;
    if (mode & (QIODevice::ReadOnly | QIODevice::Append)) {
        m_file = new QFile(filename);
        m_isSafe = false;
    } else {
        m_file = new SaveFile(filename);
        m_isSafe = true;
    }
    if (!m_file->open(QIODevice::WriteOnly | mode)) {
        QString err = QFile::exists(filename) ?
                tr("Cannot overwrite file %1: %2") : tr("Cannot create file %1: %2");
        m_errorString = err.arg(QDir::toNativeSeparators(filename), m_file->errorString());
        m_hasError = true;
    }
}

bool FileSaver::finalize()
{
    if (!m_isSafe)
        return FileSaverBase::finalize();

    SaveFile *sf = static_cast<SaveFile *>(m_file);
    if (m_hasError)
        sf->rollback();
    else
        setResult(sf->commit());
    delete sf;
    m_file = 0;
    return !m_hasError;
}

TempFileSaver::TempFileSaver(const QString &templ)
    : m_autoRemove(true)
{
    QTemporaryFile *tempFile = new QTemporaryFile();
    if (!templ.isEmpty())
        tempFile->setFileTemplate(templ);
    tempFile->setAutoRemove(false);
    if (!tempFile->open()) {
        m_errorString = tr("Cannot create temporary file in %1: %2").arg(
                QDir::toNativeSeparators(QFileInfo(tempFile->fileTemplate()).absolutePath()),
                tempFile->errorString());
        m_hasError = true;
    }
    m_file = tempFile;
    m_fileName = tempFile->fileName();
}

TempFileSaver::~TempFileSaver()
{
    delete m_file;
    m_file = 0;
    if (m_autoRemove)
        QFile::remove(m_fileName);
}

} // namespace Utils