/************************************************************************
 **
 **  @file   vtextgraphicsitem.cpp
 **  @author Bojan Kverh
 **  @date   June 16, 2016
 **
 **  @brief
 **  @copyright
 **  This source code is part of the Valentine project, a pattern making
 **  program, whose allow create and modeling patterns of clothing.
 **  Copyright (C) 2013-2015 Valentina project
 **  <https://bitbucket.org/dismine/valentina> All Rights Reserved.
 **
 **  Valentina is free software: you can redistribute it and/or modify
 **  it under the terms of the GNU General Public License as published by
 **  the Free Software Foundation, either version 3 of the License, or
 **  (at your option) any later version.
 **
 **  Valentina is distributed in the hope that it will be useful,
 **  but WITHOUT ANY WARRANTY; without even the implied warranty of
 **  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 **  GNU General Public License for more details.
 **
 **  You should have received a copy of the GNU General Public License
 **  along with Valentina.  If not, see <http://www.gnu.org/licenses/>.
 **
 *************************************************************************/

#include <QColor>
#include <QFlags>
#include <QFont>
#include <QGraphicsItem>
#include <QGraphicsSceneHoverEvent>
#include <QGraphicsSceneMouseEvent>
#include <QPainter>
#include <QPen>
#include <QPoint>
#include <QStyleOptionGraphicsItem>
#include <Qt>
#include <QDebug>

#include "../vmisc/def.h"
#include "../vmisc/vmath.h"
#include "vtextgraphicsitem.h"

const qreal resizeSquare = (3./*mm*/ / 25.4) * PrintDPI;
const qreal rotateCircle = (2./*mm*/ / 25.4) * PrintDPI;
#define ROTATE_RECT                 60
#define ROTATE_ARC                  50
const qreal minW = (4./*mm*/ / 25.4) * PrintDPI + resizeSquare;
const qreal minH = (4./*mm*/ / 25.4) * PrintDPI + resizeSquare;
#define ACTIVE_Z                    10

namespace
{
//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief GetBoundingRect calculates the bounding box around rectBB rectangle, rotated around its center by dRot degrees
 * @param rectBB rectangle of interest
 * @param dRot rectangle rotation
 * @return bounding box around rectBB rotated by dRot
 */
QRectF GetBoundingRect(QRectF rectBB, qreal dRot)
{
    QPointF apt[4] = { rectBB.topLeft(), rectBB.topRight(), rectBB.bottomLeft(), rectBB.bottomRight() };
    QPointF ptCenter = rectBB.center();

    qreal dX1 = 0;
    qreal dX2 = 0;
    qreal dY1 = 0;
    qreal dY2 = 0;

    double dAng = qDegreesToRadians(dRot);
    for (int i = 0; i < 4; ++i)
    {
        QPointF pt = apt[i] - ptCenter;
        qreal dX = pt.x()*cos(dAng) + pt.y()*sin(dAng);
        qreal dY = -pt.x()*sin(dAng) + pt.y()*cos(dAng);

        if (i == 0)
        {
            dX1 = dX2 = dX;
            dY1 = dY2 = dY;
        }
        else
        {
            if (dX < dX1)
            {
                dX1 = dX;
            }
            else if (dX > dX2)
            {
                dX2 = dX;
            }
            if (dY < dY1)
            {
                dY1 = dY;
            }
            else if (dY > dY2)
            {
                dY2 = dY;
            }
        }
    }
    QRectF rect;
    rect.setTopLeft(ptCenter + QPointF(dX1, dY1));
    rect.setWidth(dX2 - dX1);
    rect.setHeight(dY2 - dY1);
    return rect;
}
}//static functions

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief VTextGraphicsItem::VTextGraphicsItem constructor
 * @param pParent pointer to the parent item
 */
VTextGraphicsItem::VTextGraphicsItem(QGraphicsItem* pParent)
    : VPieceItem(pParent),
      m_ptStartPos(),
      m_ptStart(),
      m_szStart(),
      m_dRotation(0),
      m_dAngle(0),
      m_rectResize(),
      m_tm()
{
    m_inactiveZ = 2;
    SetSize(minW, minH);
    setZValue(m_inactiveZ);
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief VTextGraphicsItem::SetFont sets the item font
 * @param fnt font to be used in item
 */
void VTextGraphicsItem::SetFont(const QFont& fnt)
{
    m_tm.SetFont(fnt);
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief VTextGraphicsItem::paint redraws the item content
 * @param painter pointer to the QPainter in use
 * @param option pointer to the object containing the actual label rectangle
 * @param widget not used
 */
void VTextGraphicsItem::paint(QPainter *painter, const QStyleOptionGraphicsItem *option, QWidget *widget)
{
    Q_UNUSED(widget)
    Q_UNUSED(option)
    painter->fillRect(m_rectBoundingBox, QColor(251, 251, 175));
    painter->setRenderHints(QPainter::Antialiasing | QPainter::TextAntialiasing);

    painter->setPen(Qt::black);
    QFont fnt = m_tm.GetFont();
    int iW = qFloor(boundingRect().width());
    // draw text lines
    int iY = 0;
    for (int i = 0; i < m_tm.GetSourceLinesCount(); ++i)
    {
        const TextLine& tl = m_tm.GetSourceLine(i);

        fnt.setPixelSize(m_tm.GetFont().pixelSize() + tl.m_iFontSize);
        fnt.setWeight(tl.m_eFontWeight);
        fnt.setStyle(tl.m_eStyle);

        QString qsText = tl.m_qsText;
        QFontMetrics fm(fnt);

        // check if the next line will go out of bounds
        if (iY + fm.height() > boundingRect().height())
        {
            break;
        }

        if (fm.width(qsText) > iW)
        {
            qsText = fm.elidedText(qsText, Qt::ElideMiddle, iW);
        }

        painter->setFont(fnt);
        painter->drawText(0, iY, iW, fm.height(), static_cast<int>(tl.m_eAlign), qsText);
        iY += fm.height() + m_tm.GetSpacing();
    }

    // now draw the features specific to non-normal modes
    if (m_eMode != mNormal)
    {
        // outline the rectangle
        painter->setPen(QPen(Qt::black, 2, Qt::DashLine));
        painter->drawRect(boundingRect().adjusted(1, 1, -1, -1));

        if (m_eMode != mRotate)
        {
            // draw the resize square
            painter->setPen(Qt::black);
            painter->setBrush(Qt::black);
            painter->drawRect(m_rectResize.adjusted(-1, -1, -1, -1));

            if (m_eMode == mResize)
            {
                // draw the resize diagonal lines
                painter->drawLine(1, 1, qFloor(m_rectBoundingBox.width())-1, qFloor(m_rectBoundingBox.height())-1);
                painter->drawLine(1, qFloor(m_rectBoundingBox.height())-1, qFloor(m_rectBoundingBox.width())-1, 1);
            }
        }
        else
        {
            // in rotate mode, draw the circle in the middle
            painter->setPen(Qt::black);
            painter->setBrush(Qt::black);
            painter->drawEllipse(
                        QPointF(m_rectBoundingBox.width()/2, m_rectBoundingBox.height()/2),
                        rotateCircle,
                        rotateCircle
                        );
            if (m_rectBoundingBox.width() > minW*3 && m_rectBoundingBox.height() > minH*3)
            {
                painter->setPen(QPen(Qt::black, 3));
                painter->setBrush(Qt::NoBrush);
                // and then draw the arc in each of the corners
                int iTop = ROTATE_RECT - ROTATE_ARC;
                int iLeft = ROTATE_RECT - ROTATE_ARC;
                int iRight = qRound(m_rectBoundingBox.width()) - ROTATE_RECT;
                int iBottom = qRound(m_rectBoundingBox.height()) - ROTATE_RECT;
                painter->drawArc(iLeft, iTop, ROTATE_ARC, ROTATE_ARC, 180*16, -90*16);
                painter->drawArc(iRight, iTop, ROTATE_ARC, ROTATE_ARC, 90*16, -90*16);
                painter->drawArc(iLeft, iBottom, ROTATE_ARC, ROTATE_ARC, 270*16, -90*16);
                painter->drawArc(iRight, iBottom, ROTATE_ARC, ROTATE_ARC, 0*16, -90*16);
            }
        }
    }
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief VTextGraphicsItem::AddLine adds a line of text to the label list.
 * @param tl line of text to add
 */
void VTextGraphicsItem::AddLine(const TextLine& tl)
{
    m_tm.AddSourceLine(tl);
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief VTextGraphicsItem::Clear deletes all the label texts
 */
void VTextGraphicsItem::Clear()
{
    m_tm.ClearSourceLines();
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief VTextGraphicsItem::SetSize Tries to set the label size to (fW, fH). If any of those is too small, the label
 * size does not change.
 * @param fW label width
 * @param fH label height
 */
void VTextGraphicsItem::SetSize(qreal fW, qreal fH)
{
    qDebug() << "Setting size to" << fW << parentItem()->boundingRect().width();
    // don't allow resize under specific size
    if (fW > parentItem()->boundingRect().width())
    {
        fW = parentItem()->boundingRect().width();
    }
    if (fW < minW)
    {
        fW = minW;
    }
    if (fH > parentItem()->boundingRect().height())
    {
        fH = parentItem()->boundingRect().height();
    }
    if (fH < minH)
    {
        fH = minH;
    }

    prepareGeometryChange();
    qDebug() << "Actual size set to" << fW;
    m_rectBoundingBox.setTopLeft(QPointF(0, 0));
    m_rectBoundingBox.setWidth(fW);
    m_rectBoundingBox.setHeight(fH);
    m_rectResize.setTopLeft(QPointF(fW - resizeSquare, fH - resizeSquare));
    m_rectResize.setWidth(resizeSquare);
    m_rectResize.setHeight(resizeSquare);
    setTransformOriginPoint(m_rectBoundingBox.center());
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief VTextGraphicsItem::Update sets the correct size and font size and redraws the label
 */
void VTextGraphicsItem::Update()
{
    CorrectLabel();
    UpdateBox();
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief VTextGraphicsItem::IsContained checks if the bounding box around rotated rectBB is contained in
 * the parent. If that is not the case, it calculates the amount of movement needed to put it inside the parent
 * and write it into dX, dY
 * @param rectBB bounding box in question
 * @param dRot bounding box rotation in degrees
 * @param dX horizontal translation needed to put the box inside parent item
 * @param dY vertical translation needed to put the box inside parent item
 * @return true, if rectBB is contained in parent item and false otherwise
 */
bool VTextGraphicsItem::IsContained(QRectF rectBB, qreal dRot, qreal &dX, qreal &dY) const
{
    QRectF rectParent = parentItem()->boundingRect();
    rectBB = GetBoundingRect(rectBB, dRot);
    dX = 0;
    dY = 0;

    if (rectParent.contains(rectBB) == false)
    {
        if (rectParent.left() - rectBB.left() > fabs(dX))
        {
            dX = rectParent.left() - rectBB.left();
        }
        else if (rectBB.right() - rectParent.right() > fabs(dX))
        {
            dX = rectParent.right() - rectBB.right();
        }

        if (rectParent.top() - rectBB.top() > fabs(dY))
        {
            dY = rectParent.top() - rectBB.top();
        }
        else if (rectBB.bottom() - rectParent.bottom() > fabs(dY))
        {
            dY = rectParent.bottom() - rectBB.bottom();
        }

        return false;
    }
    return true;
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief VTextGraphicsItem::UpdateData Updates the detail label
 * @param qsName name of detail
 * @param data reference to VPatternPieceData
 */
void VTextGraphicsItem::UpdateData(const QString &qsName, const VPieceLabelData &data)
{
    m_tm.Update(qsName, data);
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief VTextGraphicsItem::UpdateData Updates the pattern label
 * @param pDoc pointer to the pattern object
 */
void VTextGraphicsItem::UpdateData(const VAbstractPattern* pDoc, qreal dSize, qreal dHeight)
{
    m_tm.Update(pDoc, dSize, dHeight);
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief VTextGraphicsItem::GetTextLines returns the number of lines of text to show
 * @return number of lines of text
 */
int VTextGraphicsItem::GetTextLines() const
{
    return m_tm.GetSourceLinesCount();
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief VTextGraphicsItem::GetFontSize returns the currently used text base font size
 * @return current text base font size
 */
int VTextGraphicsItem::GetFontSize() const
{
    return m_tm.GetFont().pixelSize();
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief VTextGraphicsItem::mousePressEvent handles left button mouse press events
 * @param pME pointer to QGraphicsSceneMouseEvent object
 */
void VTextGraphicsItem::mousePressEvent(QGraphicsSceneMouseEvent *pME)
{
    if (pME->button() == Qt::LeftButton && pME->type() != QEvent::GraphicsSceneMouseDoubleClick)
    {
        if (m_moveType == NotMovable)
        {
            pME->ignore();
            return;
        }

        // record the parameters of the mouse press. Specially record the position
        // of the press as the origin for the following operations
        m_ptStartPos = pos();
        m_ptStart = pME->scenePos();
        m_szStart = m_rectBoundingBox.size();
        m_ptRotCenter = mapToScene(m_rectBoundingBox.center());
        m_dAngle = GetAngle(pME->scenePos());
        m_dRotation = rotation();
        // in rotation mode, do not do any changes here, because user might want to
        // rotate the label more.

        if ((m_moveType & AllModifications ) == AllModifications)
        {
            AllUserModifications(pME->pos());
            setZValue(ACTIVE_Z);
            Update();
        }
        else if (m_moveType & IsRotatable)
        {
            if (m_moveType & IsResizable)
            {
                AllUserModifications(pME->pos());
            }
            else if (m_moveType & IsMovable)
            {
                UserRotateAndMove();
            }
            else
            {
                m_eMode = mRotate;
                SetOverrideCursor(cursorArrowCloseHand, 1, 1);
            }
            setZValue(ACTIVE_Z);
            Update();
        }
        else if (m_moveType & IsResizable)
        {
            if (m_moveType & IsRotatable)
            {
                AllUserModifications(pME->pos());
            }
            else if (m_moveType & IsMovable)
            {
                UserMoveAndResize(pME->pos());
            }
            setZValue(ACTIVE_Z);
            Update();
        }
        else if (m_moveType & IsMovable)
        {
            if (m_moveType & IsRotatable)
            {
                UserRotateAndMove();
            }
            else if (m_moveType & IsResizable)
            {
                UserMoveAndResize(pME->pos());
            }
            else
            {
                m_eMode = mMove;
                SetOverrideCursor(cursorArrowCloseHand, 1, 1);
            }

            setZValue(ACTIVE_Z);
            Update();
        }
        else
        {
            pME->ignore();
            return;
        }
    }
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief VTextGraphicsItem::mouseMoveEvent handles mouse move events
 * @param pME pointer to QGraphicsSceneMouseEvent object
 */
void VTextGraphicsItem::mouseMoveEvent(QGraphicsSceneMouseEvent* pME)
{
    qreal dX;
    qreal dY;
    QRectF rectBB;
    const QPointF ptDiff = pME->scenePos() - m_ptStart;
    if (m_eMode == mMove && m_moveType & IsMovable)
    {
        // in move mode move the label along the mouse move from the origin
        QPointF pt = m_ptStartPos + ptDiff;
        rectBB.setTopLeft(pt);
        rectBB.setWidth(m_rectBoundingBox.width());
        rectBB.setHeight(m_rectBoundingBox.height());
        // before moving label to a new position, check if it will still be inside the parent item
        if (IsContained(rectBB, rotation(), dX, dY) == false)
        {
            pt.setX(pt.x() + dX);
            pt.setY(pt.y() + dY);
        }
        setPos(pt);
        UpdateBox();
    }
    else if (m_eMode == mResize && m_moveType & IsResizable)
    {
        // in resize mode, resize the label along the mouse move from the origin
        QPointF pt;

        if (m_moveType & IsMovable)
        {
            pt = m_ptStartPos;
        }
        else
        {
            pt = m_ptRotCenter - QRectF(0, 0, m_szStart.width() + ptDiff.x(),
                                        m_szStart.height() + ptDiff.y()).center();
        }

        rectBB.setTopLeft(pt);
        QSizeF sz(m_szStart.width() + ptDiff.x(), m_szStart.height() + ptDiff.y());
        rectBB.setSize(sz);
        // before resizing the label to a new size, check if it will still be inside the parent item
        if (IsContained(rectBB, rotation(), dX, dY) == false)
        {
            sz = QSizeF(sz.width()+dX, sz.height()+dY);
        }
        else
        {
            if (not (m_moveType & IsMovable))
            {
                setPos(pt);
            }
        }

        SetSize(sz.width(), sz.height());
        Update();
        emit SignalShrink();
    }
    else if (m_eMode == mRotate && m_moveType & IsRotatable)
    {
        // if the angle from the original position is small (0.5 degrees), just remeber the new angle
        // new angle will be the starting angle for rotation
        if (fabs(m_dAngle) < 0.01)
        {
            m_dAngle = GetAngle(pME->scenePos());
            return;
        }
        // calculate the angle difference from the starting angle
        double dAng =  qRadiansToDegrees(GetAngle(pME->scenePos()) - m_dAngle);
        rectBB.setTopLeft(m_ptStartPos);
        rectBB.setWidth(m_rectBoundingBox.width());
        rectBB.setHeight(m_rectBoundingBox.height());
        // check if the rotated label will be inside the parent item and then rotate it
        if (IsContained(rectBB, m_dRotation + dAng, dX, dY) == true)
        {
            setRotation(m_dRotation + dAng);
            Update();
        }
    }
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief VTextGraphicsItem::mouseReleaseEvent handles left button mouse release events
 * @param pME pointer to QGraphicsSceneMouseEvent object
 */
void VTextGraphicsItem::mouseReleaseEvent(QGraphicsSceneMouseEvent* pME)
{
    if (pME->button() == Qt::LeftButton)
    {
        // restore the cursor
        if (m_eMode == mMove || m_eMode == mRotate)
        {
            RestoreOverrideCursor(cursorArrowCloseHand);
        }
        else if (m_eMode == mResize)
        {
            RestoreOverrideCursor(Qt::SizeFDiagCursor);
        }
        double dDist = fabs(pME->scenePos().x() - m_ptStart.x()) + fabs(pME->scenePos().y() - m_ptStart.y());
        // determine if this was just press/release (bShort == true) or user did some operation between press and release
        bool bShort = (dDist < 2);

        if (m_eMode == mMove || m_eMode == mResize)
        {   // if user just pressed and released the button, we must switch the mode to rotate
            // but if user did some operation (move/resize), emit the proper signal and update the label
            if (bShort == true)
            {
                if (m_bReleased == true && m_moveType & IsRotatable)
                {
                    m_eMode = mRotate;
                    UpdateBox();
                }
            }
            else if (m_eMode == mMove && m_moveType & IsMovable)
            {
                emit SignalMoved(pos());
                UpdateBox();
            }
            else if (m_moveType & IsResizable)
            {
                emit SignalResized(m_rectBoundingBox.width(), m_tm.GetFont().pixelSize());
                Update();
            }
        }
        else
        {   // in rotate mode, if user did just press/release, switch to move mode
            if (bShort == true && (m_moveType & IsMovable || m_moveType & IsResizable))
            {
                m_eMode = mMove;
            }
            else if (m_moveType & IsRotatable)
            {
                // if user rotated the item, emit proper signal and update the label
                emit SignalRotated(rotation());
            }
            UpdateBox();
        }
        m_bReleased = true;
    }
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief VTextGraphicsItem::hoverMoveEvent checks if cursor has to be changed
 * @param pHE pointer to the scene hover event
 */
void VTextGraphicsItem::hoverMoveEvent(QGraphicsSceneHoverEvent* pHE)
{
    if (m_eMode == mResize && m_moveType & IsResizable)
    {
        if (m_rectResize.contains(pHE->pos()) == true)
        {
            SetOverrideCursor(Qt::SizeFDiagCursor);
        }
        else
        {
            RestoreOverrideCursor(Qt::SizeFDiagCursor);
        }
    }
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief VTextGraphicsItem::hoverLeaveEvent tries to restore normal mouse cursor
 * @param pHE not used
 */
void VTextGraphicsItem::hoverLeaveEvent(QGraphicsSceneHoverEvent* pHE)
{
    Q_UNUSED(pHE)
    RestoreOverrideCursor(Qt::SizeFDiagCursor);
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief VTextGraphicsItem::UpdateBox redraws the label content
 */
void VTextGraphicsItem::UpdateBox()
{
    update(m_rectBoundingBox);
}

//---------------------------------------------------------------------------------------------------------------------
/**
 * @brief VTextGraphicsItem::UpdateFont sets the text font size, so that the entire text will
 *  just fit into the label bounding box
 */
void VTextGraphicsItem::CorrectLabel()
{
    qreal dX;
    qreal dY;
    QRectF rectBB;
    rectBB.setTopLeft(pos());
    rectBB.setSize(m_rectBoundingBox.size());
    if (IsContained(rectBB, rotation(), dX, dY) == false)
    {
        // put the label inside the pattern
        setPos(pos().x() + dX, pos().y() + dY);
    }
    m_tm.FitFontSize(m_rectBoundingBox.width(), m_rectBoundingBox.height());
    UpdateBox();
}

//---------------------------------------------------------------------------------------------------------------------
void VTextGraphicsItem::AllUserModifications(const QPointF &pos)
{
    if (m_eMode != mRotate)
    {
        UserMoveAndResize(pos);
    }
    else
    {
        SetOverrideCursor(cursorArrowCloseHand, 1, 1);
    }
}

//---------------------------------------------------------------------------------------------------------------------
void VTextGraphicsItem::UserRotateAndMove()
{
    if (m_eMode != mRotate)
    {
        m_eMode = mMove;
    }
    SetOverrideCursor(cursorArrowCloseHand, 1, 1);
}

//---------------------------------------------------------------------------------------------------------------------
void VTextGraphicsItem::UserMoveAndResize(const QPointF &pos)
{
    if (m_rectResize.contains(pos) == true)
    {
        m_eMode = mResize;
        SetOverrideCursor(Qt::SizeFDiagCursor);
    }
    else
    {
        m_eMode = mMove; // block later if need
        SetOverrideCursor(cursorArrowCloseHand, 1, 1);
    }
}