/*
   orxonox - the future of 3D-vertical-scrollers

   Copyright (C) 2004 orx

   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, or (at your option)
   any later version.

### File Specific:
   main-programmer: Patrick Boenzli
*/

#define DEBUG_SPECIAL_MODULE DEBUG_MODULE_GRAPHICS

#include "lense_flare.h"

#include "util/loading/load_param.h"
#include "util/loading/factory.h"

#include "glincl.h"
#include "texture.h"

#include "light.h"
#include "state.h"
#include "debug.h"

#include "render2D/image_plane.h"

#include "light.h"
#include "camera.h"

#include "class_id_DEPRECATED.h"

ObjectListDefinitionID(LenseFlare, CL_LENSE_FLARE);
CREATE_FACTORY(LenseFlare);

/**
 * @brief default constructor
 * @param root The XML-element to load the LenseFlare from
 */
LenseFlare::LenseFlare(const TiXmlElement* root) {
  this->registerObject(this, LenseFlare::_objectList);

    /*          length                      image scale */
    this->flareMatrix[0] = 1.0f;
    this->flareMatrix[1] = 1.0f;
    this->flareMatrix[2] = 0.5f;
    this->flareMatrix[3] = 0.5f;
    this->flareMatrix[4] = 0.33f;
    this->flareMatrix[5] = 0.25f;
    this->flareMatrix[6] = 0.125f;
    this->flareMatrix[7] = 1.0f;
    this->flareMatrix[8] = -0.5f;
    this->flareMatrix[9] = 0.5f;
    this->flareMatrix[10] = -0.25f;
    this->flareMatrix[11] = 0.15f;
    this->flareMatrix[12] = -1.82f;
    this->flareMatrix[13] = 0.25f;

    this->lightSource = (LightManager::getInstance())->getLight(0);
    PRINTF(4)("light is: %p\n", this->lightSource);

    if (root != NULL) {
        this->loadParams(root);
        this->activate();
    }

    this->bVisible = true;
    this->setSourceVisibility(false);

}


/**
 *  destroys a LenseFlare
 */
LenseFlare::~LenseFlare() {
    std::vector<ImagePlane*>::iterator it;
    for( it = flares.begin(); it != flares.end(); it++)
        delete (*it);
}


/**
 * @param root The XML-element to load the LenseFlare from
 */
void LenseFlare::loadParams(const TiXmlElement* root) {
    GraphicsEffect::loadParams(root);

    LOAD_PARAM_START_CYCLE(root, element);
    {
        LoadParam_CYCLE(element, "add-flare-texture", this, LenseFlare, addFlare)
        .describe("adds a lensflare texture to the engine");
    }
    LOAD_PARAM_END_CYCLE(element);
}


/**
 * initializes the fog effect
 */
void LenseFlare::init() {}


/**
 * activates the fog effect
 */
void LenseFlare::activate() {
    this->bActivated = true;
}


/**
 * deactivates the fog effect
 */
void LenseFlare::deactivate() {
    this->bActivated = false;
}


/**
 * @brief converts a gl mode char to a GLint
 * @param mode the mode character
 */
GLint LenseFlare::stringToFogMode(const std::string& mode) {
    return 0;
}


/**
 * @brief adds a texture flare
 * @param textureName the name of the flare texture
 *
 *  1st: Texture of the Sun/Light source itself
 *  2nd: Texture of the fist halo
 *  3rd: Texture of small burst
 *  4th: Texture of the second halo
 *  5th: Texutre of the second burst
 *  6th: Texture of the third halo
 *  7th: Texture of the third burst
 */
void LenseFlare::addFlare(const std::string& textureName) {
    if( this->flares.size() > LF_MAX_FLARES) {
        PRINTF(2)("You tried to add more than %i lense flares, ignoring\n", LF_MAX_FLARES);
        return;
    }

    ImagePlane* bb = new ImagePlane(NULL);
    if (this->flares.empty())
        bb->setLayer(E2D_LAYER_BELOW_ALL);
    bb->setTexture(textureName);
    bb->setSize(50, 50);
    this->flares.push_back(bb);
    bb->setVisibility(true);

    PRINTF(4)("Added a Lenseflare ImagePlane with texture %s\n", textureName.c_str());

    // the first flare belongs to the light source
    if( this->flares.size() == 1 && this->lightSource != NULL) {
        bb->setBindNode(static_cast<PNode*>(this->lightSource));
    }

    PRINTF(4)("Finished adding\n");
}


void LenseFlare::setSourceVisibility(bool visibility) {
    if (this->bVisible == visibility)
        return;

    std::vector<ImagePlane*>::const_iterator it;
    for(it = ++flares.begin(); it != flares.end(); it++)
        (*it)->setVisibility(visibility);
    this->bVisible = visibility;
}


/**
 * tick the effect
 */
void LenseFlare::tick(float dt) {
    if( unlikely(!this->bActivated || this->flares.size() == 0))
        return;

    // refetch light source information if needed
    if( unlikely( this->lightSource == NULL)) {
        this->lightSource = (LightManager::getInstance())->getLight(0);
        if( this->flares.size() > 0)
            this->flares[0]->setBindNode(static_cast<PNode*>(this->lightSource));
    }

    //set the frustum plane
    if (!flares.empty())
        this->setSourceVisibility(this->flares[0]->isVisible());


    // always update the screen center, it could be, that the window is resized
    this->screenCenter = Vector2D(State::getResX()/2.0f, State::getResY()/2.0f);

    // flare vector is the direction from the center to the light source
    this->flareVector = this->flares[0]->getAbsCoor2D() - this->screenCenter;
    this->distance = this->flareVector.len();
    this->flareVector.normalize();

    // now calculate the new coordinates of the billboards
    std::vector<ImagePlane*>::iterator it;
    int i;
    for( it = flares.begin(), i = 0; it != flares.end(); it++, i++) {
        // set the new position
        if( i == 0)
            continue;

        (*it)->setAbsCoor2D( this->screenCenter + this->flareVector * this->flareMatrix[i * 2] * this->distance);
        (*it)->setSize2D(50.0f * this->flareMatrix[i * 2 + 1], 50.0f * this->flareMatrix[i * 2 + 1]);
        PRINTF(5)("Tick flare %i @ (%f, %f)\n", i, (*it)->getAbsCoor2D().x, (*it)->getAbsCoor2D().y);
    }
}


/**
 * draws the LenseFlares
 */
void LenseFlare::draw() const {
    if( !this->bActivated)
        return;
}