#include "interactioncanvas.h"

InteractionCanvas::InteractionCanvas(QWidget *parent)
    : QLabel(parent)
{
    setFocusPolicy(Qt::StrongFocus);
    setMouseTracking(true);
    m_NewLine = NULL;
    m_SelectedLine = NULL;
}

void InteractionCanvas::clearLines()
{
    for (int i = 0; i < m_Lines.size(); i++)
    {
        delete m_Lines[i];
    }

    m_Lines.clear();
}

InteractionCanvas::~InteractionCanvas()
{
    clearLines();

    if (m_NewLine)
    {
        delete m_NewLine;
        m_NewLine = NULL;
    }

    if (m_SelectedLine)
    {
        delete m_SelectedLine;
        m_SelectedLine = NULL;
    }
}

void InteractionCanvas::addLine()
{
    Line *tmpLine = new Line();
    tmpLine->setP1(QPoint(10, 50));
    tmpLine->setP2(QPoint(30, 50));
    addNewLine(tmpLine);
    m_NewLine = NULL;
    m_Lines.append(tmpLine);
    changeSelectedLine(tmpLine);
}

void InteractionCanvas::addRectangle()
{
    Line *tmpLine = new Rectangle();
    addNewLine(tmpLine);
    m_NewLine = NULL;
    m_Lines.append(tmpLine);
    changeSelectedLine(tmpLine);
}

void InteractionCanvas::addEllipse()
{
    Line *tmpLine = new Ellipse();
    addNewLine(tmpLine);
    m_NewLine = NULL;
    m_Lines.append(tmpLine);
    changeSelectedLine(tmpLine);
}

void InteractionCanvas::addPolygon()
{
    Line *tmpLine = new Polygon();
    addNewLine(tmpLine);
    m_NewLine = NULL;
    m_Lines.append(tmpLine);
    changeSelectedLine(tmpLine);
}

void InteractionCanvas::read(QFile *file)
{
    m_fileName.setContent(file, false);

    QDomElement root = m_fileName.documentElement();

    if (root.tagName() == "geometric_objects")
    {
        QDomElement child = root.firstChildElement();

        Line *line = NULL;

        clearLines();

        while (!child.isNull())
        {
            line = NULL;

            if (child.tagName() == "Line")
            {
                line = new Line();
            }

            if (child.tagName() == "Rectangle")
            {
                line = new Rectangle();
            }

            if (child.tagName() == "Ellipse")
            {
                line = new Ellipse();
            }

            if (child.tagName() == "Polygon")
            {
                line = new Polygon();
            }

            if (line != NULL)
            {
                line->fromDomElement(child);
                line->setSelected(false);
                m_Lines.append(line);
            }

            child = child.nextSiblingElement();
        }
    }
}

void InteractionCanvas::write(QFile *file)
{
    const int IndentSize = 4;

    m_fileName.clear();

    QDomElement root = m_fileName.createElement("geometric_objects");

    m_fileName.appendChild(root);

    QListIterator<Line *> childs(m_Lines);

    Line *child = NULL;

    while (childs.hasNext())
    {
        child = childs.next();

        root.appendChild(child->toDomElement(&m_fileName));
    }

    QTextStream out(file);
    m_fileName.save(out, IndentSize);
}

void InteractionCanvas::mouseMoveEvent(QMouseEvent *mouseEvent)
{
    qDebug() << "InteractionCanvas:" << mouseEvent->pos();

    if (mouseEvent->buttons() == Qt::LeftButton)
    {
        if (m_SelectedLine)
        {
            m_SelectedLine->move(m_LastMousePosition, mouseEvent->pos());
        }

        if (m_NewLine)
        {
            m_NewLine->setP2(mouseEvent->pos());
        }

        update();
    }

    m_LastMousePosition = mouseEvent->pos();
}


void InteractionCanvas::mousePressEvent(QMouseEvent *mouseEvent)
{
    qDebug() << "InteractionCanvas: Mouse: pressed:" << mouseEvent->button();

    if (mouseEvent->button() == Qt::LeftButton)
    {
        if (!m_SelectedLine)
        {
            m_MousePressPoint = mouseEvent->pos();
            m_LastMousePosition = m_MousePressPoint;
            addNewLine(new Line);
            m_NewLine->setP1(m_MousePressPoint);
            m_NewLine->setP2(m_LastMousePosition);
        }
    }

    if (mouseEvent->button() ==  Qt::RightButton)
    {
        changeSelectedLine(NULL);

        for (int i = 0; i < m_Lines.size() && !m_SelectedLine; i++)
        {
            if (m_Lines[i]->isHit(mouseEvent->pos()))
            {
                changeSelectedLine(m_Lines[i]);
            }
        }
    }

    update();
}

void InteractionCanvas::mouseReleaseEvent(QMouseEvent *mouseEvent)
{
    qDebug() << "InteractionCanvas: Mouse: released:" << mouseEvent->button();

    if (mouseEvent->button() == Qt::LeftButton)
    {
        if (m_NewLine)
        {
            m_MouseReleasePoint = mouseEvent->pos();
            m_NewLine->setP2(m_MouseReleasePoint);
            m_NewLine->setSelected(false);
            m_Lines.append(m_NewLine);
            m_NewLine = NULL;
        }
    }

    update();
}

void InteractionCanvas::keyPressEvent(QKeyEvent *keyEvent)
{
    qDebug() << "InteractionCanvas: Key: pressed:" << keyEvent->key() << "(" <<
             keyEvent->text() << ")" << (keyEvent->isAutoRepeat() ? "druck" : "");

    if (!m_Lines.isEmpty() && keyEvent->key() == Qt::Key_Z &&
        keyEvent->modifiers() == Qt::ControlModifier)
    {
        if (m_SelectedLine == m_Lines.last())
        {
            m_SelectedLine = NULL;
        }

        delete m_Lines.last();
        m_Lines.removeLast();
        update();
    }
}

void InteractionCanvas::keyReleaseEvent(QKeyEvent *keyEvent)
{
    qDebug() << "InteractionCanvas: Key: released:" << keyEvent->key() << "(" <<
             keyEvent->text() << ")" << (keyEvent->isAutoRepeat() ? "druck" : "");
}

/**
 * @brief InteractionCanvas::changeSelectedLine
 * @param newSelectedLine
 * The new selected line or null to simply deselect.
 */
void InteractionCanvas::changeSelectedLine(Line *newSelectedLine)
{
    if (m_SelectedLine)
    {
        m_SelectedLine->setSelected(false);
        m_SelectedLine = NULL;
    }

    if (newSelectedLine)
    {
        m_SelectedLine = newSelectedLine;
        m_SelectedLine->setSelected(true);
    }
}

void InteractionCanvas::addNewLine(Line *newLine)
{
    if (m_NewLine)
    {
        delete m_NewLine;
        m_NewLine = NULL;
    }

    if (newLine)
    {
        m_NewLine = new Line();
    }
}

void InteractionCanvas::paintEvent(QPaintEvent *paintEvent)
{
    // Setup the Painters
    QPainter painter(this);

    if (m_NewLine)
    {
        m_NewLine->draw(&painter);
    }

    foreach (Line *line, m_Lines)
    {
        line->draw(&painter);
    }
}