/****************************************************************************

**

** All rights reserved.

** Contact: Nokia Corporation (qt-info@nokia.com)

**

** This file is part of the Qt Mobility Components.

**

** $QT_BEGIN_LICENSE:LGPL$

** No Commercial Usage

** This file contains pre-release code and may not be distributed.

** You may use this file in accordance with the terms and conditions

** contained in the Technology Preview License Agreement accompanying

** this package.

**

** GNU Lesser General Public License Usage

** Alternatively, this file may be used under the terms of the GNU Lesser

** General Public License version 2.1 as published by the Free Software

** Foundation and appearing in the file LICENSE.LGPL included in the

** packaging of this file.  Please review the following information to

** ensure the GNU Lesser General Public License version 2.1 requirements

** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.

**

** In addition, as a special exception, Nokia gives you certain additional

** rights.  These rights are described in the Nokia Qt LGPL Exception

** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.

**

** If you have questions regarding the use of this file, please contact

** Nokia at qt-info@nokia.com.

**

**

**

**

**

**

**

**

** $QT_END_LICENSE$

**

****************************************************************************/

#include "qmediatimerange.h"

QT_BEGIN_NAMESPACE

/*!

    \class QMediaTimeInterval

    \brief The QMediaTimeInterval class represents a time interval with integer precision.

    \ingroup multimedia

    An interval is specified by an inclusive start() and end() time.

    These must be set in the constructor, as this is an immutable class.

    The specific units of time represented by the class have not been defined -

    it is suitable for any times which can be represented by a signed 64 bit integer.

    The isNormal() method determines if a time interval is normal

    (a normal time interval has start() <= end()). An abnormal interval can be converted

    in to a normal interval by calling the normalized() method.

    The contains() method determines if a specified time lies within

    the time interval.

    The translated() method returns a time interval which has been translated

    forwards or backwards through time by a specified offset.

    \sa QMediaTimeRange

*/

/*!

    \fn QMediaTimeInterval::QMediaTimeInterval()

    Constructs an empty interval.

*/

QMediaTimeInterval::QMediaTimeInterval()

    : s(0)

    , e(0)

{

}

/*!

    \fn QMediaTimeInterval::QMediaTimeInterval(qint64 start, qint64 end)

    Constructs an interval with the specified \a start and \a end times.

*/

QMediaTimeInterval::QMediaTimeInterval(qint64 start, qint64 end)

    : s(start)

    , e(end)

{

}

/*!

    \fn QMediaTimeInterval::QMediaTimeInterval(const QMediaTimeInterval &other)

    Constructs an interval by taking a copy of \a other.

*/

QMediaTimeInterval::QMediaTimeInterval(const QMediaTimeInterval &other)

    : s(other.s)

    , e(other.e)

{

}

/*!

    \fn QMediaTimeInterval::start() const

    Returns the start time of the interval.

    \sa end()

*/

qint64 QMediaTimeInterval::start() const

{

    return s;

}

/*!

    \fn QMediaTimeInterval::end() const

    Returns the end time of the interval.

    \sa start()

*/

qint64 QMediaTimeInterval::end() const

{

    return e;

}

/*!

    \fn QMediaTimeInterval::contains(qint64 time) const

    Returns true if the time interval contains the specified \a time.

    That is, start() <= time <= end().

*/

bool QMediaTimeInterval::contains(qint64 time) const

{

    return isNormal() ? (s <= time && time <= e)

        : (e <= time && time <= s);

}

/*!

    \fn QMediaTimeInterval::isNormal() const

    Returns true if this time interval is normal.

    A normal time interval has start() <= end().

    \sa normalized()

*/

bool QMediaTimeInterval::isNormal() const

{

    return s <= e;

}

/*!

    \fn QMediaTimeInterval::normalized() const

    Returns a normalized version of this interval.

    If the start() time of the interval is greater than the end() time,

    then the returned interval has the start and end times swapped.

*/

QMediaTimeInterval QMediaTimeInterval::normalized() const

{

    if(s > e)

        return QMediaTimeInterval(e, s);

    return *this;

}

/*!

    \fn QMediaTimeInterval::translated(qint64 offset) const

    Returns a copy of this time interval, translated by a value of \a offset.

    An interval can be moved forward through time with a positive offset, or backward

    through time with a negative offset.

*/

QMediaTimeInterval QMediaTimeInterval::translated(qint64 offset) const

{

    return QMediaTimeInterval(s + offset, e + offset);

}

/*!

    \fn operator==(const QMediaTimeInterval &a, const QMediaTimeInterval &b)

    \relates QMediaTimeRange

    Returns true if \a a is exactly equal to \a b.

*/

bool operator==(const QMediaTimeInterval &a, const QMediaTimeInterval &b)

{

    return a.start() == b.start() && a.end() == b.end();

}

/*!

    \fn operator!=(const QMediaTimeInterval &a, const QMediaTimeInterval &b)

    \relates QMediaTimeRange

    Returns true if \a a is not exactly equal to \a b.

*/

bool operator!=(const QMediaTimeInterval &a, const QMediaTimeInterval &b)

{

    return a.start() != b.start() || a.end() != b.end();

}

class QMediaTimeRangePrivate : public QSharedData

{

public:

    QMediaTimeRangePrivate();

    QMediaTimeRangePrivate(const QMediaTimeRangePrivate &other);

    QMediaTimeRangePrivate(const QMediaTimeInterval &interval);

    QList<QMediaTimeInterval> intervals;

    void addInterval(const QMediaTimeInterval &interval);

    void removeInterval(const QMediaTimeInterval &interval);

};

QMediaTimeRangePrivate::QMediaTimeRangePrivate()

    : QSharedData()

{

}

QMediaTimeRangePrivate::QMediaTimeRangePrivate(const QMediaTimeRangePrivate &other)

    : QSharedData()

    , intervals(other.intervals)

{

}

QMediaTimeRangePrivate::QMediaTimeRangePrivate(const QMediaTimeInterval &interval)

    : QSharedData()

{

    if(interval.isNormal())

        intervals << interval;

}

void QMediaTimeRangePrivate::addInterval(const QMediaTimeInterval &interval)

{    

    // Handle normalized intervals only

    if(!interval.isNormal())

        return;

    // Find a place to insert the interval

    int i;

    for (i = 0; i < intervals.count(); i++) {

        // Insert before this element

        if(interval.s < intervals[i].s) {

            intervals.insert(i, interval);

            break;

        }

    }

    // Interval needs to be added to the end of the list

    if (i == intervals.count())

        intervals.append(interval);

    // Do we need to correct the element before us?

    if(i > 0 && intervals[i - 1].e >= interval.s - 1)

        i--;

    // Merge trailing ranges

    while (i < intervals.count() - 1

          && intervals[i].e >= intervals[i + 1].s - 1) {

        intervals[i].e = qMax(intervals[i].e, intervals[i + 1].e);

        intervals.removeAt(i + 1);

    }

}

void QMediaTimeRangePrivate::removeInterval(const QMediaTimeInterval &interval)

{

    // Handle normalized intervals only

    if(!interval.isNormal())

        return;

    for (int i = 0; i < intervals.count(); i++) {

        QMediaTimeInterval r = intervals[i];

        if (r.e < interval.s) {

            // Before the removal interval

            continue;

        } else if (interval.e < r.s) {

            // After the removal interval - stop here

            break;

        } else if (r.s < interval.s && interval.e < r.e) {

            // Split case - a single range has a chunk removed

            intervals[i].e = interval.s -1;

            addInterval(QMediaTimeInterval(interval.e + 1, r.e));

            break;

        } else if (r.s < interval.s) {

            // Trimming Tail Case

            intervals[i].e = interval.s - 1;

        } else if (interval.e < r.e) {

            // Trimming Head Case - we can stop after this

            intervals[i].s = interval.e + 1;

            break;

        } else {

            // Complete coverage case

            intervals.removeAt(i);

            --i;

        }

    }

}

/*!

    \class QMediaTimeRange

    \brief The QMediaTimeRange class represents a set of zero or more disjoint

    time intervals.

    \ingroup multimedia

    \reentrant

    The earliestTime(), latestTime(), intervals() and isEmpty()

    methods are used to get information about the current time range.

    The addInterval(), removeInterval() and clear() methods are used to modify

    the current time range.

    When adding or removing intervals from the time range, existing intervals

    within the range may be expanded, trimmed, deleted, merged or split to ensure

    that all intervals within the time range remain distinct and disjoint. As a

    consequence, all intervals added or removed from a time range must be

    \l{QMediaTimeInterval::isNormal()}{normal}.

    \sa QMediaTimeInterval

*/

/*!

    \fn QMediaTimeRange::QMediaTimeRange()

    Constructs an empty time range.

*/

QMediaTimeRange::QMediaTimeRange()

    : d(new QMediaTimeRangePrivate)

{

}

/*!

    \fn QMediaTimeRange::QMediaTimeRange(qint64 start, qint64 end)

    Constructs a time range that contains an initial interval from

    \a start to \a end inclusive.

    If the interval is not \l{QMediaTimeInterval::isNormal()}{normal},

    the resulting time range will be empty.

    \sa addInterval()

*/

QMediaTimeRange::QMediaTimeRange(qint64 start, qint64 end)

    : d(new QMediaTimeRangePrivate(QMediaTimeInterval(start, end)))

{

}

/*!

    \fn QMediaTimeRange::QMediaTimeRange(const QMediaTimeInterval &interval)

    Constructs a time range that contains an intitial interval, \a interval.

    If \a interval is not \l{QMediaTimeInterval::isNormal()}{normal},

    the resulting time range will be empty.

    \sa addInterval()

*/

QMediaTimeRange::QMediaTimeRange(const QMediaTimeInterval &interval)

    : d(new QMediaTimeRangePrivate(interval))

{

}

/*!

    \fn QMediaTimeRange::QMediaTimeRange(const QMediaTimeRange &range)

    Constructs a time range by copying another time \a range.

*/

QMediaTimeRange::QMediaTimeRange(const QMediaTimeRange &range)

    : d(range.d)

{

}

/*!

    \fn QMediaTimeRange::~QMediaTimeRange()

    Destructor.

*/

QMediaTimeRange::~QMediaTimeRange()

{

}

/*!

    \fn QMediaTimeRange::operator=(const QMediaTimeRange &other)

    Takes a copy of the \a other time range and returns itself.

*/

QMediaTimeRange &QMediaTimeRange::operator=(const QMediaTimeRange &other)

{

    d = other.d;

    return *this;

}

/*!

    \fn QMediaTimeRange::operator=(const QMediaTimeInterval &interval)

    Sets the time range to a single continuous interval, \a interval.

*/

QMediaTimeRange &QMediaTimeRange::operator=(const QMediaTimeInterval &interval)

{

    d = new QMediaTimeRangePrivate(interval);

    return *this;

}

/*!

    \fn QMediaTimeRange::earliestTime() const

    Returns the earliest time within the time range.

    For empty time ranges, this value is equal to zero.

    \sa latestTime()

*/

qint64 QMediaTimeRange::earliestTime() const

{

    if (!d->intervals.isEmpty())

        return d->intervals[0].s;

    return 0;

}

/*!

    \fn QMediaTimeRange::latestTime() const

    Returns the latest time within the time range.

    For empty time ranges, this value is equal to zero.

    \sa earliestTime()

*/

qint64 QMediaTimeRange::latestTime() const

{

    if (!d->intervals.isEmpty())

        return d->intervals[d->intervals.count() - 1].e;

    return 0;

}

/*!

    \fn QMediaTimeRange::addInterval(qint64 start, qint64 end)

    \overload

    Adds the interval specified by \a start and \a end

    to the time range.

    \sa addInterval()

*/

void QMediaTimeRange::addInterval(qint64 start, qint64 end)

{

    d->addInterval(QMediaTimeInterval(start, end));

}

/*!

    \fn QMediaTimeRange::addInterval(const QMediaTimeInterval &interval)

    Adds the specified \a interval to the time range.

    Adding intervals which are not \l{QMediaTimeInterval::isNormal()}{normal}

    is invalid, and will be ignored.

    If the specified interval is adjacent to, or overlaps existing

    intervals within the time range, these intervals will be merged.

    This operation takes \l{linear time}

    \sa removeInterval()

*/

void QMediaTimeRange::addInterval(const QMediaTimeInterval &interval)

{

    d->addInterval(interval);

}

/*!

    \fn QMediaTimeRange::addTimeRange(const QMediaTimeRange &range)

    Adds each of the intervals in \a range to this time range.

    Equivalent to calling addInterval() for each interval in \a range.

*/

void QMediaTimeRange::addTimeRange(const QMediaTimeRange &range)

{

    foreach(const QMediaTimeInterval &i, range.intervals()) {

        d->addInterval(i);

    }

}

/*!

    \fn QMediaTimeRange::removeInterval(qint64 start, qint64 end)

    \overload

    Removes the interval specified by \a start and \a end

    from the time range.

    \sa removeInterval()

*/

void QMediaTimeRange::removeInterval(qint64 start, qint64 end)

{

    d->removeInterval(QMediaTimeInterval(start, end));

}

/*!

    \fn QMediaTimeRange::removeInterval(const QMediaTimeInterval &interval)

    Removes the specified \a interval from the time range.

    Removing intervals which are not \l{QMediaTimeInterval::isNormal()}{normal}

    is invalid, and will be ignored.

    Intervals within the time range will be trimmed, split or deleted

    such that no intervals within the time range include any part of the

    target interval.

    This operation takes \l{linear time}

    \sa addInterval()

*/

void QMediaTimeRange::removeInterval(const QMediaTimeInterval &interval)

{