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** Alternatively, this file may be used under the terms of the GNU
** General Public License version 2.0 or (at your option) the GNU General
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****************************************************************************/

#include "qmlerror.h"

#include <tools/qttools.h>

#include <QtCore/qdebug.h>
#include <QtCore/qfile.h>
#include <QtCore/qstringlist.h>

#include <algorithm>

namespace QbsQmlJS {

/*!
    \class QmlError
    \since 5.0
    \inmodule QtQml
    \brief The QmlError class encapsulates a QML error.

    QmlError includes a textual description of the error, as well
    as location information (the file, line, and column). The toString()
    method creates a single-line, human-readable string containing all of
    this information, for example:
    \code
    file:///home/user/test.qml:7:8: Invalid property assignment: double expected
    \endcode

    You can use qDebug() or qWarning() to output errors to the console. This method
    will attempt to open the file indicated by the error
    and include additional contextual information.
    \code
    file:///home/user/test.qml:7:8: Invalid property assignment: double expected
            y: "hello"
               ^
    \endcode

    Note that the QtQuick 1 version is named QDeclarativeError

    \sa QQuickView::errors(), QmlComponent::errors()
*/
class QmlErrorPrivate
{
public:
    QmlErrorPrivate();

    QUrl url;
    QString description;
    int line;
    int column;
};

QmlErrorPrivate::QmlErrorPrivate()
: line(-1), column(-1)
{
}

/*!
    Creates an empty error object.
*/
QmlError::QmlError() = default;

/*!
    Creates a copy of \a other.
*/
QmlError::QmlError(const QmlError &other)
{
    *this = other;
}

/*!
    Assigns \a other to this error object.
*/
QmlError &QmlError::operator=(const QmlError &other)
{
    if (this == &other) // Self assignment guard.
        return *this;

    if (!other.d) {
        d = nullptr;
    } else {
        if (!d) d = qbs::Internal::makePimpl<QmlErrorPrivate>();
        d->url = other.d->url;
        d->description = other.d->description;
        d->line = other.d->line;
        d->column = other.d->column;
    }
    return *this;
}

/*!
    \internal
*/
QmlError::~QmlError() = default;

/*!
    Returns true if this error is valid, otherwise false.
*/
bool QmlError::isValid() const
{
    return d != nullptr;
}

/*!
    Returns the url for the file that caused this error.
*/
QUrl QmlError::url() const
{
    if (d) return d->url;
    return {};
}

/*!
    Sets the \a url for the file that caused this error.
*/
void QmlError::setUrl(const QUrl &url)
{
    if (!d) d = qbs::Internal::makePimpl<QmlErrorPrivate>();
    d->url = url;
}

/*!
    Returns the error description.
*/
QString QmlError::description() const
{
    if (d) return d->description;
    return {};
}

/*!
    Sets the error \a description.
*/
void QmlError::setDescription(const QString &description)
{
    if (!d) d = qbs::Internal::makePimpl<QmlErrorPrivate>();
    d->description = description;
}

/*!
    Returns the error line number.
*/
int QmlError::line() const
{
    if (d) return d->line;
    return -1;
}

/*!
    Sets the error \a line number.
*/
void QmlError::setLine(int line)
{
    if (!d) qbs::Internal::makePimpl<QmlErrorPrivate>();
    d->line = line;
}

/*!
    Returns the error column number.
*/
int QmlError::column() const
{
    if (d) return d->column;
    return -1;
}

/*!
    Sets the error \a column number.
*/
void QmlError::setColumn(int column)
{
    if (!d) qbs::Internal::makePimpl<QmlErrorPrivate>();
    d->column = column;
}

/*!
    Returns the error as a human readable string.
*/
QString QmlError::toString() const
{
    QString rv;
    if (url().isEmpty()) {
        rv = QStringLiteral("<Unknown File>");
    } else if (line() != -1) {
        rv = url().toString() + QLatin1Char(':') + QString::number(line());
        if (column() != -1)
            rv += QLatin1Char(':') + QString::number(column());
    } else {
        rv = url().toString();
    }

    rv += QLatin1String(": ") + description();

    return rv;
}

} // namespace QbsQmlJS

QT_BEGIN_NAMESPACE

using namespace QbsQmlJS;

/*!
    \relates QmlError
    \fn QDebug operator<<(QDebug debug, const QmlError &error)

    Outputs a human readable version of \a error to \a debug.
*/

QDebug operator<<(QDebug debug, const QmlError &error)
{
    debug << qPrintable(error.toString());

    QUrl url = error.url();

    if (error.line() > 0 && url.scheme() == QLatin1String("file")) {
        QString file = url.toLocalFile();
        QFile f(file);
        if (f.open(QIODevice::ReadOnly)) {
            QByteArray data = f.readAll();
            QTextStream stream(data, QIODevice::ReadOnly);
            qbs::setupDefaultCodec(stream);
            const QString code = stream.readAll();
            const QStringList lines = code.split(QLatin1Char('\n'));

            if (lines.size() >= error.line()) {
                const QString &line = lines.at(error.line() - 1);
                debug << "\n    " << qPrintable(line);

                if (error.column() > 0) {
                    int column = std::max(0, error.column() - 1);
                    column = std::min<int>(column, line.length());

                    QByteArray ind;
                    ind.reserve(column);
                    for (int i = 0; i < column; ++i) {
                        const QChar ch = line.at(i);
                        if (ch.isSpace())
                            ind.append(ch.unicode());
                        else
                            ind.append(' ');
                    }
                    ind.append('^');
                    debug << "\n    " << ind.constData();
                }
            }
        }
    }
    return debug;
}

QT_END_NAMESPACE
