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#include "qgridlayout.h"

#include "qapplication.h"

#include "qwidget.h"

#include "qlist.h"

#include "qsizepolicy.h"

#include "qvector.h"

#include "qvarlengtharray.h"

#include "qlayoutengine_p.h"

#include "qlayout_p.h"

QT_BEGIN_NAMESPACE

struct QGridLayoutSizeTriple

{

    QSize minS;

    QSize hint;

    QSize maxS;

};

/*

  Three internal classes related to QGridLayout: (1) QGridBox is a

  QLayoutItem with (row, column) information and (torow, tocolumn) information; (3) QGridLayoutData is

  the internal representation of a QGridLayout.

*/

class QGridBox

{

public:

    QGridBox(QLayoutItem *lit) { item_ = lit; }

    QGridBox(const QLayout *l, QWidget *wid) { item_ = QLayoutPrivate::createWidgetItem(l, wid); }

    ~QGridBox() { delete item_; }

    QSize sizeHint() const { return item_->sizeHint(); }

    QSize minimumSize() const { return item_->minimumSize(); }

    QSize maximumSize() const { return item_->maximumSize(); }

    Qt::Orientations expandingDirections() const { return item_->expandingDirections(); }

    bool isEmpty() const { return item_->isEmpty(); }

    bool hasHeightForWidth() const { return item_->hasHeightForWidth(); }

    int heightForWidth(int w) const { return item_->heightForWidth(w); }

    void setAlignment(Qt::Alignment a) { item_->setAlignment(a); }

    void setGeometry(const QRect &r) { item_->setGeometry(r); }

    Qt::Alignment alignment() const { return item_->alignment(); }

    QLayoutItem *item() { return item_; }

    QLayoutItem *takeItem() { QLayoutItem *i = item_; item_ = 0; return i; }

    int hStretch() { return item_->widget() ?

                         item_->widget()->sizePolicy().horizontalStretch() : 0; }

    int vStretch() { return item_->widget() ?

                         item_->widget()->sizePolicy().verticalStretch() : 0; }

private:

    friend class QGridLayoutPrivate;

    friend class QGridLayout;

    inline int toRow(int rr) const { return torow >= 0 ? torow : rr - 1; }

    inline int toCol(int cc) const { return tocol >= 0 ? tocol : cc - 1; }

    QLayoutItem *item_;

    int row, col;

    int torow, tocol;

};

class QGridLayoutPrivate : public QLayoutPrivate

{

    Q_DECLARE_PUBLIC(QGridLayout)

public:

    QGridLayoutPrivate();

    void add(QGridBox*, int row, int col);

    void add(QGridBox*, int row1, int row2, int col1, int col2);

    QSize sizeHint(int hSpacing, int vSpacing) const;

    QSize minimumSize(int hSpacing, int vSpacing) const;

    QSize maximumSize(int hSpacing, int vSpacing) const;

    Qt::Orientations expandingDirections(int hSpacing, int vSpacing) const;

    void distribute(QRect rect, int hSpacing, int vSpacing);

    inline int numRows() const { return rr; }

    inline int numCols() const { return cc; }

    inline void expand(int rows, int cols)

        { setSize(qMax(rows, rr), qMax(cols, cc)); }

    inline void setRowStretch(int r, int s)

        { expand(r + 1, 0); rStretch[r] = s; setDirty(); }

    inline void setColStretch(int c, int s)

        { expand(0, c + 1); cStretch[c] = s; setDirty(); }

    inline int rowStretch(int r) const { return rStretch.at(r); }

    inline int colStretch(int c) const { return cStretch.at(c); }

    inline void setRowMinimumHeight(int r, int s)

        { expand(r + 1, 0); rMinHeights[r] = s; setDirty(); }

    inline void setColumnMinimumWidth(int c, int s)

        { expand(0, c + 1); cMinWidths[c] = s; setDirty(); }

    inline int rowSpacing(int r) const { return rMinHeights.at(r); }

    inline int colSpacing(int c) const { return cMinWidths.at(c); }

    inline void setReversed(bool r, bool c) { hReversed = c; vReversed = r; }

    inline bool horReversed() const { return hReversed; }

    inline bool verReversed() const { return vReversed; }

    inline void setDirty() { needRecalc = true; hfw_width = -1; }

    inline bool isDirty() const { return needRecalc; }

    bool hasHeightForWidth(int hSpacing, int vSpacing);

    int heightForWidth(int width, int hSpacing, int vSpacing);

    int minimumHeightForWidth(int width, int hSpacing, int vSpacing);

    inline void getNextPos(int &row, int &col) { row = nextR; col = nextC; }

    inline int count() const { return things.count(); }

    QRect cellRect(int row, int col) const;

    inline QLayoutItem *itemAt(int index) const {

        if (index < things.count())

            return things.at(index)->item();

        else

            return 0;

    }

    inline QLayoutItem *takeAt(int index) {

        QLayoutItem *item = 0;

        if (index < things.count()) {

            QGridBox *b = things.takeAt(index);

            if (b) {

                item = b->takeItem();

                delete b;

            }

        }

        return item;

    }

    void getItemPosition(int index, int *row, int *column, int *rowSpan, int *columnSpan) {

        if (index < things.count()) {

            QGridBox *b =  things.at(index);

            int toRow = b->toRow(rr);

            int toCol = b->toCol(cc);

            *row = b->row;

            *column = b->col;

            *rowSpan = toRow - *row + 1;

            *columnSpan = toCol - *column +1;

        }

    }

    void deleteAll();

private:

    void setNextPosAfter(int r, int c);

    void recalcHFW(int w);

    void addHfwData(QGridBox *box, int width);

    void init();

    QSize findSize(int QLayoutStruct::*, int hSpacing, int vSpacing) const;

    void addData(QGridBox *b, const QGridLayoutSizeTriple &sizes, bool r, bool c);

    void setSize(int rows, int cols);

    void setupSpacings(QVector<QLayoutStruct> &chain, QGridBox *grid[], int fixedSpacing,

                       Qt::Orientation orientation);

    void setupLayoutData(int hSpacing, int vSpacing);

    void setupHfwLayoutData();

    void effectiveMargins(int *left, int *top, int *right, int *bottom) const;

    int rr;

    int cc;

    QVector<QLayoutStruct> rowData;

    QVector<QLayoutStruct> colData;

    QVector<QLayoutStruct> *hfwData;

    QVector<int> rStretch;

    QVector<int> cStretch;

    QVector<int> rMinHeights;

    QVector<int> cMinWidths;

    QList<QGridBox *> things;

    int hfw_width;

    int hfw_height;

    int hfw_minheight;

    int nextR;

    int nextC;

    int horizontalSpacing;

    int verticalSpacing;

    int leftMargin;

    int topMargin;

    int rightMargin;

    int bottomMargin;

    uint hReversed : 1;

    uint vReversed : 1;

    uint needRecalc : 1;

    uint has_hfw : 1;

    uint addVertical : 1;

};

void QGridLayoutPrivate::effectiveMargins(int *left, int *top, int *right, int *bottom) const

{

    int l = leftMargin;

    int t = topMargin;

    int r = rightMargin;

    int b = bottomMargin;

#ifdef Q_WS_MAC

    int leftMost = INT_MAX;

    int topMost = INT_MAX;

    int rightMost = 0;

    int bottomMost = 0;

    QWidget *w = 0;

    const int n = things.count();

    for (int i = 0; i < n; ++i) {

        QGridBox *box = things.at(i);

        QLayoutItem *itm = box->item();

        w = itm->widget();

        if (w) {

            bool visualHReversed = hReversed != (w->layoutDirection() == Qt::RightToLeft);

            QRect lir = itm->geometry();

            QRect wr = w->geometry();

            if (box->col <= leftMost) {

                if (box->col < leftMost) {

                    // we found an item even closer to the margin, discard.

                    leftMost = box->col;

                    if (visualHReversed)

                        r = rightMargin;

                    else

                        l = leftMargin;

                }

                if (visualHReversed) {

                    r = qMax(r, wr.right() - lir.right());

                } else {

                    l = qMax(l, lir.left() - wr.left());

                }

            }

            if (box->row <= topMost) {

                if (box->row < topMost) {

                    // we found an item even closer to the margin, discard.

                    topMost = box->row;

                    if (vReversed)

                        b = bottomMargin;

                    else

                        t = topMargin;

                }

                if (vReversed)

                    b = qMax(b, wr.bottom() - lir.bottom());

                else

                    t = qMax(t, lir.top() - wr.top());

            }

            if (box->toCol(cc) >= rightMost) {

                if (box->toCol(cc) > rightMost) {

                    // we found an item even closer to the margin, discard.

                    rightMost = box->toCol(cc);

                    if (visualHReversed)

                        l = leftMargin;

                    else

                        r = rightMargin;

                }

                if (visualHReversed) {

                    l = qMax(l, lir.left() - wr.left());

                } else {

                    r = qMax(r, wr.right() - lir.right());

                }

            }

            if (box->toRow(rr) >= bottomMost) {

                if (box->toRow(rr) > bottomMost) {

                    // we found an item even closer to the margin, discard.

                    bottomMost = box->toRow(rr);

                    if (vReversed)

                        t = topMargin;

                    else

                        b = bottomMargin;

                }

                if (vReversed)

                    t = qMax(t, lir.top() - wr.top());

                else

                    b = qMax(b, wr.bottom() - lir.bottom());

            }

        }

    }

#endif

    if (left)

        *left = l;

    if (top)

        *top = t;

    if (right)

        *right = r;

    if (bottom)

        *bottom = b;

}

QGridLayoutPrivate::QGridLayoutPrivate()

{

    addVertical = false;

    setDirty();

    rr = cc = 0;

    nextR = nextC = 0;

    hfwData = 0;

    hReversed = false;

    vReversed = false;

    horizontalSpacing = -1;

    verticalSpacing = -1;

}

#if 0

QGridLayoutPrivate::QGridLayoutPrivate(int nRows, int nCols)

    : rowData(0), colData(0)

{

    init();

    if (nRows  < 0) {

        nRows = 1;

        addVertical = false;

    }

    if (nCols  < 0) {

        nCols = 1;

        addVertical = true;

    }

    setSize(nRows, nCols);

}

#endif

void QGridLayoutPrivate::deleteAll()

{

    while (!things.isEmpty())

        delete things.takeFirst();

    delete hfwData;

}

bool QGridLayoutPrivate::hasHeightForWidth(int hSpacing, int vSpacing)

{

    setupLayoutData(hSpacing, vSpacing);

    return has_hfw;

}

/*

  Assumes that setupLayoutData() has been called, and that

  qGeomCalc() has filled in colData with appropriate values.

*/

void QGridLayoutPrivate::recalcHFW(int w)

{

    /*

      Go through all children, using colData and heightForWidth()

      and put the results in hfwData.

    */

    if (!hfwData)

        hfwData = new QVector<QLayoutStruct>(rr);

    setupHfwLayoutData();

    QVector<QLayoutStruct> &rData = *hfwData;

    int h = 0;

    int mh = 0;

    for (int r = 0; r < rr; r++) {

        int spacing = rData.at(r).spacing;

        h += rData.at(r).sizeHint + spacing;

        mh += rData.at(r).minimumSize + spacing;

    }

    hfw_width = w;

    hfw_height = qMin(QLAYOUTSIZE_MAX, h);

    hfw_minheight = qMin(QLAYOUTSIZE_MAX, mh);

}

int QGridLayoutPrivate::heightForWidth(int w, int hSpacing, int vSpacing)

{

    setupLayoutData(hSpacing, vSpacing);

    if (!has_hfw)

        return -1;

    int left, top, right, bottom;

    effectiveMargins(&left, &top, &right, &bottom);

    int hMargins = left + right;

    if (w - hMargins != hfw_width) {

        qGeomCalc(colData, 0, cc, 0, w - hMargins);

        recalcHFW(w - hMargins);

    }

    return hfw_height + top + bottom;

}

int QGridLayoutPrivate::minimumHeightForWidth(int w, int hSpacing, int vSpacing)

{

    (void)heightForWidth(w, hSpacing, vSpacing);

    if (!has_hfw)

        return -1;

    int top, bottom;

    effectiveMargins(0, &top, 0, &bottom);

    return hfw_minheight + top + bottom;

}

QSize QGridLayoutPrivate::findSize(int QLayoutStruct::*size, int hSpacing, int vSpacing) const

{

    QGridLayoutPrivate *that = const_cast<QGridLayoutPrivate*>(this);

    that->setupLayoutData(hSpacing, vSpacing);

    int w = 0;

    int h = 0;

    for (int r = 0; r < rr; r++)

        h += rowData.at(r).*size + rowData.at(r).spacing;

    for (int c = 0; c < cc; c++)

        w += colData.at(c).*size + colData.at(c).spacing;

    w = qMin(QLAYOUTSIZE_MAX, w);

    h = qMin(QLAYOUTSIZE_MAX, h);

    return QSize(w, h);

}

Qt::Orientations QGridLayoutPrivate::expandingDirections(int hSpacing, int vSpacing) const

{

    QGridLayoutPrivate *that = const_cast<QGridLayoutPrivate*>(this);

    that->setupLayoutData(hSpacing, vSpacing);

    Qt::Orientations ret;

    for (int r = 0; r < rr; r++) {

        if (rowData.at(r).expansive) {

            ret |= Qt::Vertical;

            break;

        }

    }

    for (int c = 0; c < cc; c++) {

        if (colData.at(c).expansive) {

            ret |= Qt::Horizontal;

            break;

        }

    }

    return ret;

}

QSize QGridLayoutPrivate::sizeHint(int hSpacing, int vSpacing) const

{

    return findSize(&QLayoutStruct::sizeHint, hSpacing, vSpacing);

}

QSize QGridLayoutPrivate::maximumSize(int hSpacing, int vSpacing) const

{

    return findSize(&QLayoutStruct::maximumSize, hSpacing, vSpacing);

}

QSize QGridLayoutPrivate::minimumSize(int hSpacing, int vSpacing) const

{

    return findSize(&QLayoutStruct::minimumSize, hSpacing, vSpacing);

}

void QGridLayoutPrivate::setSize(int r, int c)

{

    if ((int)rowData.size() < r) {

        int newR = qMax(r, rr * 2);

        rowData.resize(newR);

        rStretch.resize(newR);

        rMinHeights.resize(newR);

        for (int i = rr; i < newR; i++) {

            rowData[i].init();

            rowData[i].maximumSize = 0;

            rowData[i].pos = 0;

            rowData[i].size = 0;

            rStretch[i] = 0;

            rMinHeights[i] = 0;

        }

    }

    if ((int)colData.size() < c) {

        int newC = qMax(c, cc * 2);

        colData.resize(newC);

        cStretch.resize(newC);

        cMinWidths.resize(newC);

        for (int i = cc; i < newC; i++) {

            colData[i].init();

            colData[i].maximumSize = 0;

            colData[i].pos = 0;

            colData[i].size = 0;

            cStretch[i] = 0;

            cMinWidths[i] = 0;

        }

    }

    if (hfwData && (int)hfwData->size() < r) {

        delete hfwData;

        hfwData = 0;

        hfw_width = -1;

    }

    rr = r;

    cc = c;

}

void QGridLayoutPrivate::setNextPosAfter(int row, int col)

{

    if (addVertical) {

        if (col > nextC || (col == nextC && row >= nextR)) {

            nextR = row + 1;

            nextC = col;

            if (nextR >= rr) {

                nextR = 0;

                nextC++;

            }

        }

    } else {

        if (row > nextR || (row == nextR && col >= nextC)) {

            nextR = row;