//
//  ApplicationOverlay.cpp
//  interface/src/ui/overlays
//
//  Created by Benjamin Arnold on 5/27/14.
//  Copyright 2014 High Fidelity, Inc.
//
//  Distributed under the Apache License, Version 2.0.
//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
//

#include "InterfaceConfig.h"

#include <QOpenGLFramebufferObject>
#include <PerfStat.h>

#include "Application.h"
#include "ApplicationOverlay.h"

#include "ui/Stats.h"

ApplicationOverlay::ApplicationOverlay() : _framebufferObject(NULL),
                                           _oculusAngle(65.0f * RADIANS_PER_DEGREE),
                                           _distance(0.5f){

}

ApplicationOverlay::~ApplicationOverlay() {
    if (_framebufferObject != NULL) {
        delete _framebufferObject;
    }
}

const float WHITE_TEXT[] = { 0.93f, 0.93f, 0.93f };

// Renders the overlays either to a texture or to the screen
void ApplicationOverlay::renderOverlay(bool renderToTexture) {
    PerformanceWarning warn(Menu::getInstance()->isOptionChecked(MenuOption::PipelineWarnings), "ApplicationOverlay::displayOverlay()");

    Application* application = Application::getInstance();

    Overlays& overlays = application->getOverlays();
    QGLWidget* glWidget = application->getGLWidget();
    MyAvatar* myAvatar = application->getAvatar();
    Audio* audio = application->getAudio();
    const VoxelPacketProcessor& voxelPacketProcessor = application->getVoxelPacketProcessor();
    BandwidthMeter* bandwidthMeter = application->getBandwidthMeter();
    NodeBounds& nodeBoundsDisplay = application->getNodeBoundsDisplay();

    if (renderToTexture) {
        getFramebufferObject()->bind();
        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    }
    glEnable(GL_BLEND);
    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

    // Render 2D overlay:  I/O level bar graphs and text
    glMatrixMode(GL_PROJECTION);
    glPushMatrix();

    glLoadIdentity();
    gluOrtho2D(0, glWidget->width(), glWidget->height(), 0);
    glDisable(GL_DEPTH_TEST);
    glDisable(GL_LIGHTING);

    //  Display a single screen-size quad to create an alpha blended 'collision' flash
    if (audio->getCollisionFlashesScreen()) {
        float collisionSoundMagnitude = audio->getCollisionSoundMagnitude();
        const float VISIBLE_COLLISION_SOUND_MAGNITUDE = 0.5f;
        if (collisionSoundMagnitude > VISIBLE_COLLISION_SOUND_MAGNITUDE) {
            renderCollisionOverlay(glWidget->width(), glWidget->height(), audio->getCollisionSoundMagnitude());
        }
    }

    //  Audio VU Meter and Mute Icon
    const int MUTE_ICON_SIZE = 24;
    const int AUDIO_METER_INSET = 2;
    const int MUTE_ICON_PADDING = 10;
    const int AUDIO_METER_WIDTH = MIRROR_VIEW_WIDTH - MUTE_ICON_SIZE - AUDIO_METER_INSET - MUTE_ICON_PADDING;
    const int AUDIO_METER_SCALE_WIDTH = AUDIO_METER_WIDTH - 2 * AUDIO_METER_INSET;
    const int AUDIO_METER_HEIGHT = 8;
    const int AUDIO_METER_GAP = 5;
    const int AUDIO_METER_X = MIRROR_VIEW_LEFT_PADDING + MUTE_ICON_SIZE + AUDIO_METER_INSET + AUDIO_METER_GAP;

    int audioMeterY;
    if (Menu::getInstance()->isOptionChecked(MenuOption::Mirror)) {
        audioMeterY = MIRROR_VIEW_HEIGHT + AUDIO_METER_GAP + MUTE_ICON_PADDING;
    } else {
        audioMeterY = AUDIO_METER_GAP + MUTE_ICON_PADDING;
    }

    const float AUDIO_METER_BLUE[] = { 0.0, 0.0, 1.0 };
    const float AUDIO_METER_GREEN[] = { 0.0, 1.0, 0.0 };
    const float AUDIO_METER_RED[] = { 1.0, 0.0, 0.0 };
    const float AUDIO_GREEN_START = 0.25 * AUDIO_METER_SCALE_WIDTH;
    const float AUDIO_RED_START = 0.80 * AUDIO_METER_SCALE_WIDTH;
    const float CLIPPING_INDICATOR_TIME = 1.0f;
    const float AUDIO_METER_AVERAGING = 0.5;
    const float LOG2 = log(2.f);
    const float METER_LOUDNESS_SCALE = 2.8f / 5.f;
    const float LOG2_LOUDNESS_FLOOR = 11.f;
    float audioLevel = 0.f;
    float loudness = audio->getLastInputLoudness() + 1.f;

    _trailingAudioLoudness = AUDIO_METER_AVERAGING * _trailingAudioLoudness + (1.f - AUDIO_METER_AVERAGING) * loudness;
    float log2loudness = log(_trailingAudioLoudness) / LOG2;

    if (log2loudness <= LOG2_LOUDNESS_FLOOR) {
        audioLevel = (log2loudness / LOG2_LOUDNESS_FLOOR) * METER_LOUDNESS_SCALE * AUDIO_METER_SCALE_WIDTH;
    } else {
        audioLevel = (log2loudness - (LOG2_LOUDNESS_FLOOR - 1.f)) * METER_LOUDNESS_SCALE * AUDIO_METER_SCALE_WIDTH;
    }
    if (audioLevel > AUDIO_METER_SCALE_WIDTH) {
        audioLevel = AUDIO_METER_SCALE_WIDTH;
    }
    bool isClipping = ((audio->getTimeSinceLastClip() > 0.f) && (audio->getTimeSinceLastClip() < CLIPPING_INDICATOR_TIME));

    if ((audio->getTimeSinceLastClip() > 0.f) && (audio->getTimeSinceLastClip() < CLIPPING_INDICATOR_TIME)) {
        const float MAX_MAGNITUDE = 0.7f;
        float magnitude = MAX_MAGNITUDE * (1 - audio->getTimeSinceLastClip() / CLIPPING_INDICATOR_TIME);
        renderCollisionOverlay(glWidget->width(), glWidget->height(), magnitude, 1.0f);
    }

    audio->renderToolBox(MIRROR_VIEW_LEFT_PADDING + AUDIO_METER_GAP,
                         audioMeterY,
                         Menu::getInstance()->isOptionChecked(MenuOption::Mirror));

    audio->renderScope(glWidget->width(), glWidget->height());

    glBegin(GL_QUADS);
    if (isClipping) {
        glColor3f(1, 0, 0);
    } else {
        glColor3f(0.475f, 0.475f, 0.475f);
    }

    audioMeterY += AUDIO_METER_HEIGHT;

    glColor3f(0, 0, 0);
    //  Draw audio meter background Quad
    glVertex2i(AUDIO_METER_X, audioMeterY);
    glVertex2i(AUDIO_METER_X + AUDIO_METER_WIDTH, audioMeterY);
    glVertex2i(AUDIO_METER_X + AUDIO_METER_WIDTH, audioMeterY + AUDIO_METER_HEIGHT);
    glVertex2i(AUDIO_METER_X, audioMeterY + AUDIO_METER_HEIGHT);

    if (audioLevel > AUDIO_RED_START) {
        if (!isClipping) {
            glColor3fv(AUDIO_METER_RED);
        } else {
            glColor3f(1, 1, 1);
        }
        // Draw Red Quad
        glVertex2i(AUDIO_METER_X + AUDIO_METER_INSET + AUDIO_RED_START, audioMeterY + AUDIO_METER_INSET);
        glVertex2i(AUDIO_METER_X + AUDIO_METER_INSET + audioLevel, audioMeterY + AUDIO_METER_INSET);
        glVertex2i(AUDIO_METER_X + AUDIO_METER_INSET + audioLevel, audioMeterY + AUDIO_METER_HEIGHT - AUDIO_METER_INSET);
        glVertex2i(AUDIO_METER_X + AUDIO_METER_INSET + AUDIO_RED_START, audioMeterY + AUDIO_METER_HEIGHT - AUDIO_METER_INSET);
        audioLevel = AUDIO_RED_START;
    }
    if (audioLevel > AUDIO_GREEN_START) {
        if (!isClipping) {
            glColor3fv(AUDIO_METER_GREEN);
        } else {
            glColor3f(1, 1, 1);
        }
        // Draw Green Quad
        glVertex2i(AUDIO_METER_X + AUDIO_METER_INSET + AUDIO_GREEN_START, audioMeterY + AUDIO_METER_INSET);
        glVertex2i(AUDIO_METER_X + AUDIO_METER_INSET + audioLevel, audioMeterY + AUDIO_METER_INSET);
        glVertex2i(AUDIO_METER_X + AUDIO_METER_INSET + audioLevel, audioMeterY + AUDIO_METER_HEIGHT - AUDIO_METER_INSET);
        glVertex2i(AUDIO_METER_X + AUDIO_METER_INSET + AUDIO_GREEN_START, audioMeterY + AUDIO_METER_HEIGHT - AUDIO_METER_INSET);
        audioLevel = AUDIO_GREEN_START;
    }
    //   Draw Blue Quad
    if (!isClipping) {
        glColor3fv(AUDIO_METER_BLUE);
    } else {
        glColor3f(1, 1, 1);
    }
    // Draw Blue (low level) quad
    glVertex2i(AUDIO_METER_X + AUDIO_METER_INSET, audioMeterY + AUDIO_METER_INSET);
    glVertex2i(AUDIO_METER_X + AUDIO_METER_INSET + audioLevel, audioMeterY + AUDIO_METER_INSET);
    glVertex2i(AUDIO_METER_X + AUDIO_METER_INSET + audioLevel, audioMeterY + AUDIO_METER_HEIGHT - AUDIO_METER_INSET);
    glVertex2i(AUDIO_METER_X + AUDIO_METER_INSET, audioMeterY + AUDIO_METER_HEIGHT - AUDIO_METER_INSET);
    glEnd();


    if (Menu::getInstance()->isOptionChecked(MenuOption::HeadMouse)) {
        myAvatar->renderHeadMouse(glWidget->width(), glWidget->height());
    }

    //  Display stats and log text onscreen
    glLineWidth(1.0f);
    glPointSize(1.0f);

    if (Menu::getInstance()->isOptionChecked(MenuOption::Stats)) {
        // let's set horizontal offset to give stats some margin to mirror
        int horizontalOffset = MIRROR_VIEW_WIDTH + MIRROR_VIEW_LEFT_PADDING * 2;
        int voxelPacketsToProcess = voxelPacketProcessor.packetsToProcessCount();
        //  Onscreen text about position, servers, etc
        Stats::getInstance()->display(WHITE_TEXT, horizontalOffset, application->getFps(), application->getPacketsPerSecond(), application->getBytesPerSecond(), voxelPacketsToProcess);
        //  Bandwidth meter
        if (Menu::getInstance()->isOptionChecked(MenuOption::Bandwidth)) {
            Stats::drawBackground(0x33333399, glWidget->width() - 296, glWidget->height() - 68, 296, 68);
            bandwidthMeter->render(glWidget->width(), glWidget->height());
        }
    }

    //  Show on-screen msec timer
    if (Menu::getInstance()->isOptionChecked(MenuOption::FrameTimer)) {
        char frameTimer[10];
        quint64 mSecsNow = floor(usecTimestampNow() / 1000.0 + 0.5);
        sprintf(frameTimer, "%d\n", (int)(mSecsNow % 1000));
        int timerBottom =
            (Menu::getInstance()->isOptionChecked(MenuOption::Stats) &&
            Menu::getInstance()->isOptionChecked(MenuOption::Bandwidth))
            ? 80 : 20;
        drawText(glWidget->width() - 100, glWidget->height() - timerBottom, 0.30f, 0.0f, 0, frameTimer, WHITE_TEXT);
    }
    nodeBoundsDisplay.drawOverlay();

    // give external parties a change to hook in
    emit application->renderingOverlay();

    overlays.render2D();

    glPopMatrix();

    glMatrixMode(GL_MODELVIEW);
    glEnable(GL_DEPTH_TEST);
    glEnable(GL_LIGHTING);
    glBlendFuncSeparate(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA, GL_CONSTANT_ALPHA, GL_ONE);

    if (renderToTexture) {
        getFramebufferObject()->release();
    }
}

// Draws the FBO texture for the screen
void ApplicationOverlay::displayOverlayTexture(Camera& whichCamera) {

    Application* application = Application::getInstance();
    QGLWidget* glWidget = application->getGLWidget();

    glEnable(GL_TEXTURE_2D);
    glActiveTexture(GL_TEXTURE0);
    glBindTexture(GL_TEXTURE_2D, getFramebufferObject()->texture());

    glMatrixMode(GL_PROJECTION);
    glPushMatrix();

    glLoadIdentity();
    gluOrtho2D(0, glWidget->width(), glWidget->height(), 0);
    glDisable(GL_DEPTH_TEST);
    glDisable(GL_LIGHTING);

    glBegin(GL_QUADS);
    glTexCoord2f(0, 0); glVertex2i(0, glWidget->height());
    glTexCoord2f(1, 0); glVertex2i(glWidget->width(), glWidget->height());
    glTexCoord2f(1, 1); glVertex2i(glWidget->width(), 0);
    glTexCoord2f(0, 1); glVertex2i(0, 0);
    glEnd();

    glPopMatrix();
    glDisable(GL_TEXTURE_2D);
}

// Draws the FBO texture for Oculus rift. TODO: Draw a curved texture instead of plane.
void ApplicationOverlay::displayOverlayTextureOculus(Camera& whichCamera) {

    Application* application = Application::getInstance();

    QGLWidget* glWidget = application->getGLWidget();
    MyAvatar* myAvatar = application->getAvatar();
    const glm::vec3& viewMatrixTranslation = application->getViewMatrixTranslation();

    // Get vertical FoV of the displayed overlay texture
    const float halfVerticalAngle = _oculusAngle / 2.0f;
    const float overlayAspectRatio = glWidget->width() / (float)glWidget->height();
    const float halfOverlayHeight = _distance * tan(halfVerticalAngle);

    // The more vertices, the better the curve
    const int numHorizontalVertices = 20;
    // U texture coordinate width at each quad
    const float quadTexWidth = 1.0f / (numHorizontalVertices - 1);

    // Get horizontal angle and angle increment from vertical angle and aspect ratio
    const float horizontalAngle = halfVerticalAngle * 2.0f * overlayAspectRatio;
    const float angleIncrement = horizontalAngle / (numHorizontalVertices - 1);
    const float halfHorizontalAngle = horizontalAngle / 2;

    glActiveTexture(GL_TEXTURE0);

    glDepthMask(GL_FALSE);
    glEnable(GL_BLEND);
    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);

    glBindTexture(GL_TEXTURE_2D, getFramebufferObject()->texture());
    glDisable(GL_DEPTH_TEST);
    glDisable(GL_LIGHTING);
    glEnable(GL_TEXTURE_2D);

    glMatrixMode(GL_MODELVIEW);

    glPushMatrix();
    glLoadIdentity();
    // Transform to world space
    glm::quat rotation = whichCamera.getRotation();
    glm::vec3 axis2 = glm::axis(rotation);
    glRotatef(-glm::degrees(glm::angle(rotation)), axis2.x, axis2.y, axis2.z);
    glTranslatef(viewMatrixTranslation.x, viewMatrixTranslation.y, viewMatrixTranslation.z);

    // Translate to the front of the camera
    glm::vec3 pos = whichCamera.getPosition();
    glm::quat rot = myAvatar->getOrientation();
    glm::vec3 axis = glm::axis(rot);
   
    glTranslatef(pos.x, pos.y, pos.z);
    glRotatef(glm::degrees(glm::angle(rot)), axis.x, axis.y, axis.z);
    
    float leftX, rightX, leftZ, rightZ;

    glColor3f(1.0f, 1.0f, 1.0f);
    glBegin(GL_QUADS);

    // Place the vertices in a semicircle curve around the camera
    for (int i = 0; i < numHorizontalVertices-1; i++) {

        // Calculate the X and Z coordinates from the angles and radius from camera
        leftX = sin(angleIncrement * i - halfHorizontalAngle) * _distance;
        rightX = sin(angleIncrement * (i + 1) - halfHorizontalAngle) * _distance;
        leftZ = -cos(angleIncrement * i - halfHorizontalAngle) * _distance;
        rightZ = -cos(angleIncrement * (i + 1) - halfHorizontalAngle) * _distance;

        glTexCoord2f(quadTexWidth * i, 1); glVertex3f(leftX, halfOverlayHeight, leftZ);
        glTexCoord2f(quadTexWidth * (i + 1), 1); glVertex3f(rightX,  halfOverlayHeight, rightZ);
        glTexCoord2f(quadTexWidth * (i + 1), 0); glVertex3f(rightX, -halfOverlayHeight, rightZ);
        glTexCoord2f(quadTexWidth * i, 0); glVertex3f(leftX, -halfOverlayHeight, leftZ);
    }

    glEnd();

    glPopMatrix();

    glEnable(GL_DEPTH_TEST);
    glDepthMask(GL_TRUE);
    glBindTexture(GL_TEXTURE_2D, 0);
    glDisable(GL_TEXTURE_2D);

    glBlendFuncSeparate(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA, GL_CONSTANT_ALPHA, GL_ONE);
    glEnable(GL_LIGHTING);

}

QOpenGLFramebufferObject* ApplicationOverlay::getFramebufferObject() {
    if (!_framebufferObject) {
        _framebufferObject = new QOpenGLFramebufferObject(Application::getInstance()->getGLWidget()->size());

        glBindTexture(GL_TEXTURE_2D, _framebufferObject->texture());
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
        glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
        glBindTexture(GL_TEXTURE_2D, 0);
    }
    return _framebufferObject;
}