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#include "qdrawutil.h"

#include "qbitmap.h"

#include "qpixmapcache.h"

#include "qapplication.h"

#include "qpainter.h"

#include "qpalette.h"

#include <private/qpaintengineex_p.h>

#include <qvarlengtharray.h>

#include <qmath.h>

QT_BEGIN_NAMESPACE

/*!

    \headerfile <qdrawutil.h>

    \title Drawing Utility Functions

    \sa QPainter

*/

/*!

    \fn void qDrawShadeLine(QPainter *painter, int x1, int y1, int x2, int y2,

                     const QPalette &palette, bool sunken,

                     int lineWidth, int midLineWidth)

    \relates <qdrawutil.h>

    Draws a horizontal (\a y1 == \a y2) or vertical (\a x1 == \a x2)

    shaded line using the given \a painter.  Note that nothing is

    drawn if \a y1 != \a y2 and \a x1 != \a x2 (i.e. the line is

    neither horizontal nor vertical).

    The provided \a palette specifies the shading colors (\l

    {QPalette::light()}{light}, \l {QPalette::dark()}{dark} and \l

    {QPalette::mid()}{middle} colors).  The given \a lineWidth

    specifies the line width for each of the lines; it is not the

    total line width. The given \a midLineWidth specifies the width of

    a middle line drawn in the QPalette::mid() color.

    The line appears sunken if \a sunken is true, otherwise raised.

    \warning This function does not look at QWidget::style() or

    QApplication::style().  Use the drawing functions in QStyle to

    make widgets that follow the current GUI style.

    Alternatively you can use a QFrame widget and apply the

    QFrame::setFrameStyle() function to display a shaded line:

    \snippet doc/src/snippets/code/src_gui_painting_qdrawutil.cpp 0

    \sa qDrawShadeRect(), qDrawShadePanel(), QStyle

*/

void qDrawShadeLine(QPainter *p, int x1, int y1, int x2, int y2,

                     const QPalette &pal, bool sunken,

                     int lineWidth, int midLineWidth)

{

    if (!(p && lineWidth >= 0 && midLineWidth >= 0))        {

        qWarning("qDrawShadeLine: Invalid parameters");

        return;

    }

    int tlw = lineWidth*2 + midLineWidth;        // total line width

    QPen oldPen = p->pen();                        // save pen

    if (sunken)

        p->setPen(pal.color(QPalette::Dark));

    else

        p->setPen(pal.light().color());

    QPolygon a;

    int i;

    if (y1 == y2) {                                // horizontal line

        int y = y1 - tlw/2;

        if (x1 > x2) {                        // swap x1 and x2

            int t = x1;

            x1 = x2;

            x2 = t;

        }

        x2--;

        for (i=0; i<lineWidth; i++) {                // draw top shadow

            a.setPoints(3, x1+i, y+tlw-1-i,

                         x1+i, y+i,

                         x2-i, y+i);

            p->drawPolyline(a);

        }

        if (midLineWidth > 0) {

            p->setPen(pal.mid().color());

            for (i=0; i<midLineWidth; i++)        // draw lines in the middle

                p->drawLine(x1+lineWidth, y+lineWidth+i,

                             x2-lineWidth, y+lineWidth+i);

        }

        if (sunken)

            p->setPen(pal.light().color());

        else

            p->setPen(pal.dark().color());

        for (i=0; i<lineWidth; i++) {                // draw bottom shadow

            a.setPoints(3, x1+i, y+tlw-i-1,

                         x2-i, y+tlw-i-1,

                         x2-i, y+i+1);

            p->drawPolyline(a);

        }

    }

    else if (x1 == x2) {                        // vertical line

        int x = x1 - tlw/2;

        if (y1 > y2) {                        // swap y1 and y2

            int t = y1;

            y1 = y2;

            y2 = t;

        }

        y2--;

        for (i=0; i<lineWidth; i++) {                // draw left shadow

            a.setPoints(3, x+i, y2,

                         x+i, y1+i,

                         x+tlw-1, y1+i);

            p->drawPolyline(a);

        }

        if (midLineWidth > 0) {

            p->setPen(pal.mid().color());

            for (i=0; i<midLineWidth; i++)        // draw lines in the middle

                p->drawLine(x+lineWidth+i, y1+lineWidth, x+lineWidth+i, y2);

        }

        if (sunken)

            p->setPen(pal.light().color());

        else

            p->setPen(pal.dark().color());

        for (i=0; i<lineWidth; i++) {                // draw right shadow

            a.setPoints(3, x+lineWidth, y2-i,

                         x+tlw-i-1, y2-i,

                         x+tlw-i-1, y1+lineWidth);

            p->drawPolyline(a);

        }

    }

    p->setPen(oldPen);

}

/*!

    \fn void qDrawShadeRect(QPainter *painter, int x, int y, int width, int height,

                     const QPalette &palette, bool sunken,

                     int lineWidth, int midLineWidth,

                     const QBrush *fill)

    \relates <qdrawutil.h>

    Draws the shaded rectangle beginning at (\a x, \a y) with the

    given \a width and \a height using the provided \a painter.

    The provide \a palette specifies the shading colors (\l

    {QPalette::light()}{light}, \l {QPalette::dark()}{dark} and \l

    {QPalette::mid()}{middle} colors.  The given \a lineWidth

    specifies the line width for each of the lines; it is not the

    total line width.  The \a midLineWidth specifies the width of a

    middle line drawn in the QPalette::mid() color.  The rectangle's

    interior is filled with the \a fill brush unless \a fill is 0.

    The rectangle appears sunken if \a sunken is true, otherwise

    raised.

    \warning This function does not look at QWidget::style() or

    QApplication::style(). Use the drawing functions in QStyle to make

    widgets that follow the current GUI style.

    Alternatively you can use a QFrame widget and apply the

    QFrame::setFrameStyle() function to display a shaded rectangle:

    \snippet doc/src/snippets/code/src_gui_painting_qdrawutil.cpp 1

    \sa qDrawShadeLine(), qDrawShadePanel(), qDrawPlainRect(), QStyle

*/

void qDrawShadeRect(QPainter *p, int x, int y, int w, int h,

                     const QPalette &pal, bool sunken,

                     int lineWidth, int midLineWidth,

                     const QBrush *fill)

{

    if (w == 0 || h == 0)

        return;

    if (! (w > 0 && h > 0 && lineWidth >= 0 && midLineWidth >= 0)) {

        qWarning("qDrawShadeRect: Invalid parameters");

        return;

    }

    QPen oldPen = p->pen();

    if (sunken)

        p->setPen(pal.dark().color());

    else

        p->setPen(pal.light().color());

    int x1=x, y1=y, x2=x+w-1, y2=y+h-1;

    if (lineWidth == 1 && midLineWidth == 0) {// standard shade rectangle

        p->drawRect(x1, y1, w-2, h-2);

        if (sunken)

            p->setPen(pal.light().color());

        else

            p->setPen(pal.dark().color());

        QLineF lines[4] = { QLineF(x1+1, y1+1, x2-2, y1+1),

                            QLineF(x1+1, y1+2, x1+1, y2-2),

                            QLineF(x1, y2, x2, y2),

                            QLineF(x2,y1, x2,y2-1) };

        p->drawLines(lines, 4);              // draw bottom/right lines

    } else {                                        // more complicated

        int m = lineWidth+midLineWidth;

        int i, j=0, k=m;

        for (i=0; i<lineWidth; i++) {                // draw top shadow

            QLineF lines[4] = { QLineF(x1+i, y2-i, x1+i, y1+i),

                                QLineF(x1+i, y1+i, x2-i, y1+i),

                                QLineF(x1+k, y2-k, x2-k, y2-k),

                                QLineF(x2-k, y2-k, x2-k, y1+k) };

            p->drawLines(lines, 4);

            k++;

        }

        p->setPen(pal.mid().color());

        j = lineWidth*2;

        for (i=0; i<midLineWidth; i++) {        // draw lines in the middle

            p->drawRect(x1+lineWidth+i, y1+lineWidth+i, w-j-1, h-j-1);

            j += 2;

        }

        if (sunken)

            p->setPen(pal.light().color());

        else

            p->setPen(pal.dark().color());

        k = m;

        for (i=0; i<lineWidth; i++) {                // draw bottom shadow

            QLineF lines[4] = { QLineF(x1+1+i, y2-i, x2-i, y2-i),

                                QLineF(x2-i, y2-i, x2-i, y1+i+1),

                                QLineF(x1+k, y2-k, x1+k, y1+k),

                                QLineF(x1+k, y1+k, x2-k, y1+k) };

            p->drawLines(lines, 4);

            k++;

        }

    }

    if (fill) {

        QBrush oldBrush = p->brush();

        int tlw = lineWidth + midLineWidth;

        p->setPen(Qt::NoPen);

        p->setBrush(*fill);

        p->drawRect(x+tlw, y+tlw, w-2*tlw, h-2*tlw);

        p->setBrush(oldBrush);

    }

    p->setPen(oldPen);                        // restore pen

}

/*!

    \fn void qDrawShadePanel(QPainter *painter, int x, int y, int width, int height,

                      const QPalette &palette, bool sunken,

                      int lineWidth, const QBrush *fill)

    \relates <qdrawutil.h>

    Draws the shaded panel beginning at (\a x, \a y) with the given \a

    width and \a height using the provided \a painter and the given \a

    lineWidth.

    The given \a palette specifies the shading colors (\l

    {QPalette::light()}{light}, \l {QPalette::dark()}{dark} and \l

    {QPalette::mid()}{middle} colors).  The panel's interior is filled

    with the \a fill brush unless \a fill is 0.

    The panel appears sunken if \a sunken is true, otherwise raised.

    \warning This function does not look at QWidget::style() or

    QApplication::style(). Use the drawing functions in QStyle to make

    widgets that follow the current GUI style.

    Alternatively you can use a QFrame widget and apply the

    QFrame::setFrameStyle() function to display a shaded panel:

    \snippet doc/src/snippets/code/src_gui_painting_qdrawutil.cpp 2

    \sa qDrawWinPanel(), qDrawShadeLine(), qDrawShadeRect(), QStyle

*/

void qDrawShadePanel(QPainter *p, int x, int y, int w, int h,

                      const QPalette &pal, bool sunken,

                      int lineWidth, const QBrush *fill)

{

    if (w == 0 || h == 0)

        return;

    if (!(w > 0 && h > 0 && lineWidth >= 0)) {

        qWarning("qDrawShadePanel: Invalid parameters");

    }

    QColor shade = pal.dark().color();

    QColor light = pal.light().color();

    if (fill) {

        if (fill->color() == shade)

            shade = pal.shadow().color();

        if (fill->color() == light)

            light = pal.midlight().color();

    }

    QPen oldPen = p->pen();                        // save pen

    QVector<QLineF> lines;

    lines.reserve(2*lineWidth);

    if (sunken)

        p->setPen(shade);

    else

        p->setPen(light);

    int x1, y1, x2, y2;

    int i;

    x1 = x;

    y1 = y2 = y;

    x2 = x+w-2;

    for (i=0; i<lineWidth; i++) {                // top shadow

        lines << QLineF(x1, y1++, x2--, y2++);

    }

    x2 = x1;

    y1 = y+h-2;

    for (i=0; i<lineWidth; i++) {                // left shado

        lines << QLineF(x1++, y1, x2++, y2--);

    }

    p->drawLines(lines);

    lines.clear();

    if (sunken)

        p->setPen(light);

    else

        p->setPen(shade);

    x1 = x;

    y1 = y2 = y+h-1;

    x2 = x+w-1;

    for (i=0; i<lineWidth; i++) {                // bottom shadow

        lines << QLineF(x1++, y1--, x2, y2--);

    }

    x1 = x2;

    y1 = y;

    y2 = y+h-lineWidth-1;

    for (i=0; i<lineWidth; i++) {                // right shadow

        lines << QLineF(x1--, y1++, x2--, y2);

    }

    p->drawLines(lines);

    if (fill)                                // fill with fill color

        p->fillRect(x+lineWidth, y+lineWidth, w-lineWidth*2, h-lineWidth*2, *fill);

    p->setPen(oldPen);                        // restore pen

}

/*!

  \internal

  This function draws a rectangle with two pixel line width.

  It is called from qDrawWinButton() and qDrawWinPanel().

  c1..c4 and fill are used:

    1 1 1 1 1 2

    1 3 3 3 4 2

    1 3 F F 4 2

    1 3 F F 4 2

    1 4 4 4 4 2

    2 2 2 2 2 2

*/

static void qDrawWinShades(QPainter *p,

                           int x, int y, int w, int h,

                           const QColor &c1, const QColor &c2,

                           const QColor &c3, const QColor &c4,

                           const QBrush *fill)

{

    if (w < 2 || h < 2)                        // can't do anything with that

        return;

    QPen oldPen = p->pen();

    QPoint a[3] = { QPoint(x, y+h-2), QPoint(x, y), QPoint(x+w-2, y) };

    p->setPen(c1);

    p->drawPolyline(a, 3);

    QPoint b[3] = { QPoint(x, y+h-1), QPoint(x+w-1, y+h-1), QPoint(x+w-1, y) };

    p->setPen(c2);

    p->drawPolyline(b, 3);

    if (w > 4 && h > 4) {

        QPoint c[3] = { QPoint(x+1, y+h-3), QPoint(x+1, y+1), QPoint(x+w-3, y+1) };

        p->setPen(c3);

        p->drawPolyline(c, 3);

        QPoint d[3] = { QPoint(x+1, y+h-2), QPoint(x+w-2, y+h-2), QPoint(x+w-2, y+1) };

        p->setPen(c4);

        p->drawPolyline(d, 3);

        if (fill)

            p->fillRect(QRect(x+2, y+2, w-4, h-4), *fill);

    }

    p->setPen(oldPen);

}

/*!

    \fn void qDrawWinButton(QPainter *painter, int x, int y, int width, int height,

                     const QPalette &palette, bool sunken,

                     const QBrush *fill)

    \relates <qdrawutil.h>

    Draws the Windows-style button specified by the given point (\a x,

    \a y}, \a width and \a height using the provided \a painter with a

    line width of 2 pixels. The button's interior is filled with the

    \a{fill} brush unless \a fill is 0.

    The given \a palette specifies the shading colors (\l

    {QPalette::light()}{light}, \l {QPalette::dark()}{dark} and \l

    {QPalette::mid()}{middle} colors).

    The button appears sunken if \a sunken is true, otherwise raised.

    \warning This function does not look at QWidget::style() or

    QApplication::style()-> Use the drawing functions in QStyle to make

    widgets that follow the current GUI style.

    \sa qDrawWinPanel(), QStyle

*/

void qDrawWinButton(QPainter *p, int x, int y, int w, int h,

                     const QPalette &pal, bool sunken,

                     const QBrush *fill)

{

    if (sunken)

        qDrawWinShades(p, x, y, w, h,

                       pal.shadow().color(), pal.light().color(), pal.dark().color(),

                       pal.button().color(), fill);

    else

        qDrawWinShades(p, x, y, w, h,

                       pal.light().color(), pal.shadow().color(), pal.button().color(),

                       pal.dark().color(), fill);

}

/*!

    \fn void qDrawWinPanel(QPainter *painter, int x, int y, int width, int height,

                    const QPalette &palette, bool        sunken,

                    const QBrush *fill)

    \relates <qdrawutil.h>

    Draws the Windows-style panel specified by the given point(\a x,

    \a y), \a width and \a height using the provided \a painter with a

    line width of 2 pixels. The button's interior is filled with the

    \a fill brush unless \a fill is 0.

    The given \a palette specifies the shading colors.  The panel

    appears sunken if \a sunken is true, otherwise raised.

    \warning This function does not look at QWidget::style() or

    QApplication::style(). Use the drawing functions in QStyle to make

    widgets that follow the current GUI style.

    Alternatively you can use a QFrame widget and apply the

    QFrame::setFrameStyle() function to display a shaded panel:

    \snippet doc/src/snippets/code/src_gui_painting_qdrawutil.cpp 3

    \sa qDrawShadePanel(), qDrawWinButton(), QStyle

*/

void qDrawWinPanel(QPainter *p, int x, int y, int w, int h,

                    const QPalette &pal, bool        sunken,

                    const QBrush *fill)

{

    if (sunken)

        qDrawWinShades(p, x, y, w, h,

                        pal.dark().color(), pal.light().color(), pal.shadow().color(),

                       pal.midlight().color(), fill);

    else

        qDrawWinShades(p, x, y, w, h,

                       pal.light().color(), pal.shadow().color(), pal.midlight().color(),

                       pal.dark().color(), fill);

}

/*!

    \fn void qDrawPlainRect(QPainter *painter, int x, int y, int width, int height, const QColor &lineColor,

                     int lineWidth, const QBrush *fill)

    \relates <qdrawutil.h>

    Draws the plain rectangle beginning at (\a x, \a y) with the given

    \a width and \a height, using the specified \a painter, \a lineColor

    and \a lineWidth. The rectangle's interior is filled with the \a

    fill brush unless \a fill is 0.

    \warning This function does not look at QWidget::style() or

    QApplication::style(). Use the drawing functions in QStyle to make

    widgets that follow the current GUI style.

    Alternatively you can use a QFrame widget and apply the

    QFrame::setFrameStyle() function to display a plain rectangle:

    \snippet doc/src/snippets/code/src_gui_painting_qdrawutil.cpp 4

    \sa qDrawShadeRect(), QStyle

*/

void qDrawPlainRect(QPainter *p, int x, int y, int w, int h, const QColor &c,

                     int lineWidth, const QBrush *fill)

{

    if (w == 0 || h == 0)

        return;

    if (!(w > 0 && h > 0 && lineWidth >= 0)) {

        qWarning("qDrawPlainRect: Invalid parameters");

    }

    QPen   oldPen   = p->pen();

    QBrush oldBrush = p->brush();

    p->setPen(c);

    p->setBrush(Qt::NoBrush);

    for (int i=0; i<lineWidth; i++)

        p->drawRect(x+i, y+i, w-i*2 - 1, h-i*2 - 1);