//-----------------------------------------------------------------------------
// Copyright (C) Matt Meyer
//-----------------------------------------------------------------------------

#include "dgl/dgl.h"
#include "gui/controls/guiBitmapCtrl.h"
#include "console/consoleTypes.h"
#include "game/gameConnection.h"
#include "game/vehicles/vehicle.h"

//-----------------------------------------------------------------------------
/// An Energy meter control.
/// This gui displays the energy of the current Vehicle based
/// control object. This control only works if a server
/// connection exists and it's control object is a vehicle. If
/// either of these requirements is false, the control is not rendered.
class GuiEnergyMeterHud : public GuiBitmapCtrl
{
   typedef GuiBitmapCtrl Parent;

   F32   mEnergy;        ///< Current energy
   F32   mMaxEnergy;     ///< Max energy at max need pos
   F32   mMaxAngle;     ///< Max pos of needle
   F32   mMinAngle;     ///< Min pos of needle
   Point2F mCenter;     ///< Center of needle rotation
   ColorF mColor;       ///< Needle Color
   F32   mNeedleLength;
   F32   mNeedleWidth;
   F32   mTailLength;

public:
   GuiEnergyMeterHud();

   void onRender( Point2I, const RectI &);
   static void initPersistFields();
   DECLARE_CONOBJECT( GuiEnergyMeterHud );
};


//-----------------------------------------------------------------------------

IMPLEMENT_CONOBJECT( GuiEnergyMeterHud );

GuiEnergyMeterHud::GuiEnergyMeterHud()
{
   mEnergy = 0;
   mMaxEnergy = 100;
   mMaxAngle = 0;
   mMinAngle = 200;
   mCenter.set(0,0);
   mNeedleWidth = 3;
   mNeedleLength = 10;
   mTailLength = 5;
   mColor.set(0,0,1,1);
}

void GuiEnergyMeterHud::initPersistFields()
{
   Parent::initPersistFields();

   addGroup("Needle");
   addField("maxEnergy", TypeF32, Offset( mMaxEnergy, GuiEnergyMeterHud ) );
   addField("minAngle", TypeF32, Offset( mMinAngle, GuiEnergyMeterHud) );
   addField("maxAngle", TypeF32, Offset( mMaxAngle, GuiEnergyMeterHud) );
   addField("color", TypeColorF, Offset( mColor, GuiEnergyMeterHud) );
   addField("center", TypePoint2F, Offset( mCenter, GuiEnergyMeterHud) );
   addField("length", TypeF32, Offset( mNeedleLength, GuiEnergyMeterHud) );
   addField("width", TypeF32, Offset( mNeedleWidth, GuiEnergyMeterHud) );
   addField("tail", TypeF32, Offset( mTailLength, GuiEnergyMeterHud) );
   endGroup("Needle");
}


//-----------------------------------------------------------------------------
/**
   Gui onRender method.
   Renders a energy health bar with filled background and border.
*/
void GuiEnergyMeterHud::onRender(Point2I offset, const RectI &updateRect)
{
   // Must have a connection and player control object
   GameConnection* conn = GameConnection::getConnectionToServer();
   if (!conn)
      return;
   Vehicle* control = dynamic_cast<Vehicle*>(conn->getControlObject());
   if (!control)
      return;

   Parent::onRender(offset,updateRect);

   // Use the vehicle's energy as its fuel/energy...
   mEnergy = control->getEnergyLevel();
   if (mEnergy > mMaxEnergy)
      mEnergy = mMaxEnergy;

   // Render the needle
   glPushMatrix();
   Point2F center = mCenter;
   if (center.x == F32(0) && center.y == F32(0)) {
      center.x = mBounds.extent.x / 2;
      center.y = mBounds.extent.y / 2;
   }
   glTranslatef(mBounds.point.x + center.x,mBounds.point.y + center.y,0);

   F32 rotation = mMinAngle + (mMaxAngle - mMinAngle) * (mEnergy / mMaxEnergy);
   glRotatef(rotation,0.0f,0.0f,-1.0f);

   glEnable(GL_BLEND);
   glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
   glDisable(GL_TEXTURE_2D);

   glColor4f(mColor.red, mColor.green, mColor.blue, mColor.alpha);
   glBegin(GL_LINE_LOOP);
      glVertex2f(+mNeedleLength,-mNeedleWidth);
      glVertex2f(+mNeedleLength,+mNeedleWidth);
      glVertex2f(-mTailLength ,+mNeedleWidth);
      glVertex2f(-mTailLength ,-mNeedleWidth);
   glEnd();
   glPopMatrix();
}