/*
 *  kis_tool_line.cc - part of Krayon
 *
 *  Copyright (c) 2000 John Califf
 *  Copyright (c) 2002 Patrick Julien <freak@codepimps.org>
 *  Copyright (c) 2003 Boudewijn Rempt <boud@valdyas.org>
 *
 *  This program 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 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program 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 this program; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 */

#include <tqpainter.h>
#include <tqlayout.h>
#include <tqwidget.h>

#include <kdebug.h>
#include <tdeaction.h>
#include <kcommand.h>
#include <tdelocale.h>

#include "kis_cursor.h"
#include "kis_painter.h"
#include "kis_tool_line.h"
#include "kis_button_press_event.h"
#include "kis_button_release_event.h"
#include "kis_move_event.h"
#include "kis_paintop_registry.h"
#include "kis_canvas_subject.h"
#include "kis_undo_adapter.h"
#include "kis_canvas.h"
#include "kis_canvas_painter.h"
#include "kis_cursor.h"
#include "kis_layer.h"

KisToolLine::KisToolLine()
    : super(i18n("Line")),
      m_dragging( false )
{
    setName("tool_line");
    setCursor(KisCursor::load("tool_line_cursor.png", 6, 6));

    m_painter = 0;
    m_currentImage = 0;
    m_startPos = KisPoint(0, 0);
    m_endPos = KisPoint(0, 0);
}

KisToolLine::~KisToolLine()
{
}

void KisToolLine::update(KisCanvasSubject *subject)
{
    m_subject = subject;
    m_currentImage = subject->currentImg();

    super::update(m_subject);
}


void KisToolLine::paint(KisCanvasPainter& gc)
{
    if (m_dragging)
        paintLine(gc, TQRect());
}

void KisToolLine::paint(KisCanvasPainter& gc, const TQRect& rc)
{
    if (m_dragging)
        paintLine(gc, rc);
}

void KisToolLine::buttonPress(KisButtonPressEvent *e)
{
    if (!m_subject || !m_currentImage) return;

    if (!m_subject->currentBrush()) return;

    if (e->button() == Qt::LeftButton) {
        m_dragging = true;
        //KisCanvasController *controller = m_subject->canvasController();
        m_startPos = e->pos(); //controller->windowToView(e->pos());
        m_endPos = e->pos(); //controller->windowToView(e->pos());
    }
}

void KisToolLine::move(KisMoveEvent *e)
{
    if (m_dragging) {
        if (m_startPos != m_endPos)
            paintLine();
        //KisCanvasController *controller = m_subject->canvasController();

        if (e->state() & TQt::AltButton) {
            KisPoint trans = e->pos() - m_endPos;
            m_startPos += trans;
            m_endPos += trans;
        } else if (e->state() & TQt::ShiftButton)
            m_endPos = straightLine(e->pos());
        else
            m_endPos = e->pos();//controller->windowToView(e->pos());
        paintLine();
    }
}

void KisToolLine::buttonRelease(KisButtonReleaseEvent *e)
{
    if (m_dragging && e->button() == Qt::LeftButton) {
        m_dragging = false;
        KisCanvasController *controller = m_subject->canvasController();
        KisImageSP img = m_subject->currentImg();

        if (m_startPos == m_endPos) {
            controller->updateCanvas();
            m_dragging = false;
            return;
        }

        if ((e->state() & TQt::ShiftButton) == TQt::ShiftButton) {
            m_endPos = straightLine(e->pos());
        }
        else {
            m_endPos = e->pos();
        }

        KisPaintDeviceSP device;
        if (m_currentImage &&
            (device = m_currentImage->activeDevice()) &&
            m_subject &&
            m_subject->currentBrush())
        {
            delete m_painter;
            m_painter = new KisPainter( device );
            TQ_CHECK_PTR(m_painter);

            if (m_currentImage->undo()) m_painter->beginTransaction(i18n("Line"));

            m_painter->setPaintColor(m_subject->fgColor());
            m_painter->setBrush(m_subject->currentBrush());
            m_painter->setOpacity(m_opacity);
            m_painter->setCompositeOp(m_compositeOp);
            KisPaintOp * op = KisPaintOpRegistry::instance()->paintOp(m_subject->currentPaintop(), m_subject->currentPaintopSettings(), m_painter);
            m_painter->setPaintOp(op); // Painter takes ownership
            m_painter->paintLine(m_startPos, PRESSURE_DEFAULT, 0, 0, m_endPos, PRESSURE_DEFAULT, 0, 0);
            device->setDirty( m_painter->dirtyRect() );
            notifyModified();

            /* remove remains of the line drawn while moving */
            if (controller->kiscanvas()) {
                controller->kiscanvas()->update();
            }

            if (m_currentImage->undo() && m_painter) {
                m_currentImage->undoAdapter()->addCommand(m_painter->endTransaction());
            }
            delete m_painter;
            m_painter = 0;
        } else {
            if (m_painter)
                controller->updateCanvas(m_painter->dirtyRect()); // Removes the last remaining line.
        }
    }

}

KisPoint KisToolLine::straightLine(KisPoint point)
{
    KisPoint comparison = point - m_startPos;
    KisPoint result;

    if ( fabs(comparison.x()) > fabs(comparison.y())) {
        result.setX(point.x());
        result.setY(m_startPos.y());
    } else {
        result.setX( m_startPos.x() );
        result.setY( point.y() );
    }

    return result;
}

void KisToolLine::paintLine()
{
    if (m_subject) {
        KisCanvasController *controller = m_subject->canvasController();
        KisCanvas *canvas = controller->kiscanvas();
        KisCanvasPainter gc(canvas);
        TQRect rc;

        paintLine(gc, rc);
    }
}

void KisToolLine::paintLine(KisCanvasPainter& gc, const TQRect&)
{
    if (m_subject) {
        KisCanvasController *controller = m_subject->canvasController();
        RasterOp op = gc.rasterOp();
        TQPen old = gc.pen();
        TQPen pen(TQt::SolidLine);
        KisPoint start;
        KisPoint end;

//        Q_ASSERT(controller);
        start = controller->windowToView(m_startPos);
        end = controller->windowToView(m_endPos);
//          start.setX(start.x() - controller->horzValue());
//          start.setY(start.y() - controller->vertValue());
//          end.setX(end.x() - controller->horzValue());
//          end.setY(end.y() - controller->vertValue());
//          end.setX((end.x() - start.x()));
//          end.setY((end.y() - start.y()));
//         start *= m_subject->zoomFactor();
//         end *= m_subject->zoomFactor();
        gc.setRasterOp(TQt::NotROP);
        gc.setPen(pen);
        gc.drawLine(start.floorTQPoint(), end.floorTQPoint());
        gc.setRasterOp(op);
        gc.setPen(old);
    }
}

void KisToolLine::setup(TDEActionCollection *collection)
{
    m_action = static_cast<TDERadioAction *>(collection->action(name()));

    if (m_action == 0) {
        m_action = new TDERadioAction(i18n("&Line"),
                        "tool_line", TQt::Key_L, this,
                        TQT_SLOT(activate()), collection,
                        name());
        m_action->setToolTip(i18n("Draw a line"));
        m_action->setExclusiveGroup("tools");
        m_ownAction = true;
    }
}

TQString KisToolLine::quickHelp() const {
    return i18n("Alt+Drag will move the origin of the currently displayed line around, Shift+Drag will force you to draw straight lines");
}

#include "kis_tool_line.moc"