/* OpenSceneGraph example, osgtext.
*
*  Permission is hereby granted, free of charge, to any person obtaining a copy
*  of this software and associated documentation files (the "Software"), to deal
*  in the Software without restriction, including without limitation the rights
*  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
*  copies of the Software, and to permit persons to whom the Software is
*  furnished to do so, subject to the following conditions:
*
*  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
*  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
*  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
*  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
*  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
*  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
*  THE SOFTWARE.
*/

#include <sstream>
#include <iomanip>

#include <osgDB/WriteFile>

#include <osgGA/StateSetManipulator>
#include <osgViewer/Viewer>
#include <osgViewer/ViewerEventHandlers>

#include <osg/Geode>
#include <osg/Camera>

#include <osgText/Font>
#include <osgText/Text>

////////////////////////////////////////////////////////////////////

std::string printRightText(double angle)
{
    std::stringstream ss;
    ss << "Press 2 to change the font between\n"
        << "arial and times.\n"
        << std::fixed << std::setprecision(1) << angle << "\n";
    return ss.str();
}

struct UpdateColumnPosition : public osg::Callback
{
    UpdateColumnPosition(osgText::Text* leftText, osgText::Text* rightText)
      : angleValue(0.0),
        left(leftText),
        right(rightText)
    {
    }

    virtual bool run(osg::Object* object, osg::Object* data)
    {
        angleValue = fmod(angleValue + 1.7, 360.0);
        right->setText(printRightText(angleValue));

        // Position the text appropriately
        left->setPosition(osg::Vec3f(10.0, 10.0, 0.0));
        osg::BoundingBox bb = left->getBoundingBox();
        const float width = bb.xMax() - bb.xMin();
        right->setPosition(osg::Vec3f(10.0 + width + 30.0, 10.0, 0.0));

        return traverse(object, data);
    }

    double angleValue;
    osg::ref_ptr<osgText::Text> left;
    osg::ref_ptr<osgText::Text> right;
};

struct ToggleLeftRightTextSettings : public osgGA::GUIEventHandler
{
    ToggleLeftRightTextSettings(osgText::Text* leftText, osgText::Text* rightText)
      : left(leftText),
        right(rightText),
        useShadow(true),
        useArial(true)
    {
    }

    virtual bool handle(const osgGA::GUIEventAdapter& ea, osgGA::GUIActionAdapter& aa, osg::Object*, osg::NodeVisitor*)
    {
        if (ea.getEventType() == ea.KEYDOWN)
        {
            if (ea.getKey() == '1')
            {
                useShadow = !useShadow;
                left->setBackdropType(useShadow ? osgText::Text::DROP_SHADOW_BOTTOM_RIGHT : osgText::Text::NONE);
                right->setBackdropType(left->getBackdropType());
                return true;
            }
            else if (ea.getKey() == '2')
            {
                useArial = !useArial;
                left->setFont(useArial ? "fonts/arial.ttf" : "fonts/times.ttf");
                right->setFont(left->getFont());
                return true;
            }
        }
        return false;
    }

    osg::ref_ptr<osgText::Text> left;
    osg::ref_ptr<osgText::Text> right;
    bool useShadow;
    bool useArial;
};

osg::Group* sampleHud(int width, int height)
{
    osg::Camera* hud = new osg::Camera;
    hud->setRenderOrder(osg::Camera::POST_RENDER, 1000);
    hud->setProjectionMatrix(osg::Matrix::ortho2D(0, width - 1, 0, height - 1));
    hud->setReferenceFrame(osg::Transform::ABSOLUTE_RF);
    hud->setViewMatrix(osg::Matrix::identity());
    hud->setClearMask(GL_DEPTH_BUFFER_BIT);
    hud->setAllowEventFocus(true);
    hud->getOrCreateStateSet()->setRenderBinDetails(0, "TraversalOrderBin");
    hud->getOrCreateStateSet()->setMode(GL_CULL_FACE, osg::StateAttribute::OFF);

    static const float TEXT_SIZE = 16.0;
    static const osgText::Text::BackdropType BACKDROP_TYPE = osgText::Text::DROP_SHADOW_BOTTOM_RIGHT;
    static const std::string FONT_NAME = "fonts/arial.ttf";

    osgText::Text* leftText = new osgText::Text;
    leftText->setFont(FONT_NAME);
    leftText->setColor(osg::Vec4f(0.0f, 1.0f, 1.0f, 1.0f));
    leftText->setPosition(osg::Vec3f(10.0f, 10.0f, 0.0f));
    leftText->setCharacterSize(TEXT_SIZE);
    leftText->setAlignment(osgText::TextBase::LEFT_BOTTOM_BASE_LINE);
    leftText->setBackdropType(BACKDROP_TYPE);
    leftText->setDataVariance(osg::Object::DYNAMIC);
    //leftText->setText("Time:\nTime Step:\nDistance:\nAzim:\nElev:\nCentered:");
    leftText->setText("Press 1\nTo Toggle\nShadow");
    hud->addChild(leftText);

    osgText::Text* rightText = new osgText::Text;
    rightText->setFont(FONT_NAME);
    rightText->setColor(osg::Vec4f(0.0f, 1.0f, 1.0f, 1.0f));
    rightText->setPosition(osg::Vec3f(180.0f, 10.0f, 0.0f));
    rightText->setCharacterSize(TEXT_SIZE);
    rightText->setAlignment(osgText::TextBase::LEFT_BOTTOM_BASE_LINE);
    rightText->setBackdropType(BACKDROP_TYPE);
    rightText->setDataVariance(osg::Object::DYNAMIC);
    rightText->setText(printRightText(0.0));
    hud->addChild(rightText);

    hud->addUpdateCallback(new UpdateColumnPosition(leftText, rightText));
    hud->addEventCallback(new ToggleLeftRightTextSettings(leftText, rightText));

    return hud;
}

struct UpdateTextCallback : public osg::Callback
{
    UpdateTextCallback() : value(100) {}
    virtual bool run(osg::Object* object, osg::Object* data)
    {
        osgText::Text* text5 = dynamic_cast<osgText::Text*>(object);
        value = (value + 7) % 360;

        std::stringstream ss;
        ss << "Long text string\n" << value << ".0";
        text5->setText(ss.str());
        text5->setBackdropType(osgText::Text::DROP_SHADOW_BOTTOM_RIGHT);
        text5->setDataVariance(osg::Object::DYNAMIC);

        osg::BoundingBox bb = text5->getBoundingBox();
        std::cout << "xDelta: " << bb.xMax() - bb.xMin()
            << "  yDelta: " << bb.yMax() - bb.yMin()
            << "  zDelta: " << bb.zMax() - bb.zMin()
            << "\n";
        return traverse(object, data);
    }
    int value;
};


// create text which sits in 3D space such as would be inserted into a normal model
osg::Group* create3DText(const osg::Vec3& center,float radius)
{

    osg::Geode* geode  = new osg::Geode;

////////////////////////////////////////////////////////////////////////////////////////////////////////
//
// Examples of how to set up axis/orientation alignments
//

    osg::Vec3 pos(center.x()-radius*.5f,center.y()-radius*.5f,center.z()-radius*.5f);
    osg::Vec4 characterSizeModeColor(1.0f,0.0f,0.5f,1.0f);

    osgText::Text* text5 = new osgText::Text;
    text5->setColor(characterSizeModeColor);
    //text5->setFont("fonts/times.ttf");
    text5->setFont("fonts/arial.ttf");
    text5->setCharacterSize(32.0f); // medium
    text5->setPosition(center - osg::Vec3(0.0, 0.0, 0.2));
    text5->setAxisAlignment(osgText::Text::SCREEN);
    text5->setCharacterSizeMode(osgText::Text::SCREEN_COORDS);
    text5->setDrawMode(osgText::Text::TEXT | osgText::Text::BOUNDINGBOX);
    text5->setText("CharacterSizeMode SCREEN_COORDS(size 32.0)");
    geode->addDrawable(text5);
    text5->addUpdateCallback(new UpdateTextCallback);

    osg::Group* rootNode = new osg::Group;
    rootNode->addChild(geode);

    return rootNode;
}

int main(int argc, char** argv)
{
    osg::ArgumentParser arguments(&argc, argv);

    // construct the viewer.
    osgViewer::Viewer viewer(arguments);

    // prepare scene.
    osg::Vec3 center(0.0f, 0.0f, 0.0f);
    float radius = 1.0f;

    // make sure the root node is group so we can add extra nodes to it.
    osg::Group* group = new osg::Group;

    if (true)
    {
        group->addChild(create3DText(center, radius));
    }

    if (true)
    {
        // Determine the screen width and height; realize viewer to get reasonable viewport easily for demo
        viewer.realize();
        const osg::Viewport* vp = viewer.getCamera()->getViewport();
        group->addChild(sampleHud(vp->width(), vp->height()));
    }

    // set the scene to render
    viewer.setSceneData(group);

    std::string filename;
    if (arguments.read("-o",filename))
    {
        osgDB::writeNodeFile(*viewer.getSceneData(),filename);
        return 0;
    }

    viewer.addEventHandler( new osgGA::StateSetManipulator(viewer.getCamera()->getOrCreateStateSet()) );
    viewer.addEventHandler(new osgViewer::StatsHandler());

    viewer.run();

    return 0;
}