//
//  SuperTuxKart - a fun racing game with go-kart
//  Copyright (C) 2012  Joerg Henrichs
//
//  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 3
//  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., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

#include "tracks/check_goal.hpp"

#include "io/xml_node.hpp"
#include "tracks/track.hpp"
#include "tracks/track_object_manager.hpp"
#include "modes/soccer_world.hpp"
#include <stdio.h>

/** Constructor for a check goal line.
 *  \param node XML node containing the parameters for this goal line.
 *  \param index Index of this check structure in the check manager.
 */
CheckGoal::CheckGoal(const XMLNode &node,  unsigned int index) 
           : CheckStructure(node, index)
{
    // Determine the team for this goal
    m_first_goal = false;
    node.get("first_goal", &m_first_goal);
    
    Vec3 p1, p2;
    node.get("p1", &p1);
    node.get("p2", &p2);
    
    m_line.setLine( core::vector2df(p1.getX(), p1.getZ()),
                    core::vector2df(p2.getX(), p2.getZ()) );
}   // CheckGoal

// ----------------------------------------------------------------------------
/**
 * Checks the soccer balls to see if they crossed the line and trigger the goal accordingly.
 */
void CheckGoal::update(float dt)
{
    World *world = World::getWorld();
    assert(world);
    
    Track* track = world->getTrack();
    assert(track);
    
    TrackObjectManager* tom = track->getTrackObjectManager();
    assert(tom);
    
    PtrVector<TrackObject>&   objects = tom->getObjects();
    unsigned int ball_index = 0;
    for(int i=0; i<objects.size(); i++)
    {
        TrackObject* obj = objects.get(i);
        if(!obj->isSoccerBall())
            continue;
        
        const Vec3 &xyz = obj->getPresentation<TrackObjectPresentationMesh>()->getNode()->getPosition();
        if(isTriggered(m_previous_position[ball_index], xyz, ball_index))
        {
            if(UserConfigParams::m_check_debug)
                printf("CHECK: Goal check structure %d triggered for object %s.\n",
                       m_index, obj->getPresentation<TrackObjectPresentationMesh>()->getNode()->getDebugName());
            trigger(ball_index);
        }
        m_previous_position[ball_index] = xyz;
        ball_index++;
    }
}

// ----------------------------------------------------------------------------
/** Called when the check line is triggered. This function  creates a cannon 
 *  animation object and attaches it to the kart.
 *  \param kart_index The index of the kart that triggered the check line.
 */
void CheckGoal::trigger(unsigned int kart_index)
{
    SoccerWorld* world = dynamic_cast<SoccerWorld*>(World::getWorld());
    if(!world)
    {
        fprintf(stderr, "WARNING: no soccer world found, cannot count the points\n");
        return;
    }
    
    world->onCheckGoalTriggered(m_first_goal);
}   // CheckGoal

bool CheckGoal::isTriggered(const Vec3 &old_pos, const Vec3 &new_pos, 
                            unsigned int indx)
{
    core::vector2df cross_point;
    
    // Check if the finite line was actually crossed:
    return m_line.intersectWith(core::line2df(old_pos.toIrrVector2d(), 
                                              new_pos.toIrrVector2d()), 
                                cross_point);
    
}   // isTriggered

void CheckGoal::reset(const Track &track)
{
    const TrackObjectManager* tom = track.getTrackObjectManager();
    assert(tom);
    
    m_previous_position.clear();
    
    const PtrVector<TrackObject>&   objects = tom->getObjects();
    for(int i=0; i<objects.size(); i++)
    {
        const TrackObject* obj = objects.get(i);
        if(!obj->isSoccerBall())
            continue;
        
        const Vec3 &xyz = obj->getPresentation<TrackObjectPresentationMesh>()->getNode()->getPosition();
        
        m_previous_position.push_back(xyz);
    }
}   // reset