// Copyright Hugh Perkins 2006, 2009
// hughperkins@gmail.com http://manageddreams.com
//
// 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 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 in the file licence.txt; if not, write to the
// Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-
// 1307 USA
// You can find the licence also on the web at:
// http://www.opensource.org/licenses/gpl-license.php
//
// ======================================================================================
//

package hughai.packcoordinators;

import java.util.*;

import com.springrts.ai.*;
import com.springrts.ai.oo.clb.*;

import hughai.*;
import hughai.utils.*;
import hughai.basictypes.*;
import hughai.unitdata.*;

// this manages an attack pack, eg group of tanks
// specifically ,ensures they stay together, rather than streaming
// in theory
public class AttackPackCoordinator extends PackCoordinator
{
   public float MaxPackDiameterOuterThreshold = 500;
   public float MaxPackDiameterInnerThreshold = 300;
   public float movetothreshold = 20;
   public int MaxPackToConsider = 5;

   public float AttackDistance = 50;

   //	HashMap< Integer,UnitDef> UnitDefListByDeployedId;
   TerrainPos targetpos;

   UnitController unitController;

   //public delegate void AttackPackDeadHandler();

   //public event AttackPackDeadHandler AttackPackDeadEvent;

   // can pass in pointer to a hashtable in another class if we want
   // ie other class can directly modify our hashtable
   public AttackPackCoordinator( PlayerObjects playerObjects )
   {
      super(playerObjects);
      this.unitController = playerObjects.getUnitController();

      csai.registerGameListener( new GameListenerHandler() );
      //		csai.TickEvent += new CSAI.TickHandler( this.Tick );
   }

   // does NOT imply Activate()
   @Override
   public void SetTarget( TerrainPos newtarget )
   {
      this.targetpos = newtarget;
      //Activate();
   }

   TerrainPos lasttargetpos = null;

   @Override
   void Recoordinate()
   {
      if( !activated )
      {
         return;
      }

      // first we scan the list to find the 5 closest units to target, in order
      // next we measure distance of first unit from 5th
      // if distance is less than MaxPackDiameter, we move in
      // otherwise 5th unit holds, and we move units to position of 5th unit
      // pack must have at least 5 units, otherwise we call AttackPackDead event

      if( !CheckIfPackAlive() )
      {
         return;
      }

      logfile.WriteLine( this.getClass().getSimpleName() + " recoordinate" );
      int packsize = Math.min(MaxPackToConsider, unitsControlled.size());
      UnitInfo[] closestunits = GetClosestUnits(targetpos, packsize);
      if( closestunits.length == 0 ) {
         return;
      }
      TerrainPos packheadpos = closestunits[0].pos;
      TerrainPos packtailpos = closestunits[packsize - 1].pos;
      double packsquareddiameter = packheadpos.GetSquaredDistance( packtailpos );
      csai.DebugSay("packsize: " + packsize + " packdiameter: " + Math.sqrt(packsquareddiameter));
      // logfile.WriteLine( "AttackPackCoordinator packheadpos " + packheadpos.toString() + " packtailpos " + packtailpos.toString() + " packsquareddiamter " + packsquareddiameter );
      if (( regrouping && ( packsquareddiameter < (MaxPackDiameterInnerThreshold * MaxPackDiameterInnerThreshold) ) ) ||
            (!regrouping && ( packsquareddiameter < (MaxPackDiameterOuterThreshold * MaxPackDiameterOuterThreshold)) ))
      {
         regrouping = false;
         csai.DebugSay("attacking");
         Attack( closestunits);
      }
      else
      {
         csai.DebugSay("regrouping");
         regrouping = true;
         Regroup(closestunits[(packsize / 2)].pos);
      }
   }

   //boolean attacking = false;
   boolean regrouping = false;

   // placeholder...
   void GetAttackDistance(UnitInfo[]closestunits)
   {
      // for( UnitInfo unitinfo : closestunits )
      //    {
      //       if( unitinfo.unitdef.
      //   }
   }

   void Attack(UnitInfo[] closestunits)
   {
      //logfile.WriteLine( "AttackPackCoordinator attacking" );
      //if( debugon )
      // {
      //      aicallback.SendTextMsg( "AttackPackCoordinator attacking", 0 );
      // }

      // get vector from head unit to target
      // pick point a bit behind target, backwards along vector
      TerrainPos vectortargettohead = 
         targetpos.subtract( closestunits[0].pos );
      vectortargettohead.Normalize();
      //vectortargettohead = vectortargettohead * AttackDistance;
      MoveTo( targetpos.add( vectortargettohead.multiply( AttackDistance ) ) );
   }

   void Regroup( TerrainPos regouppos )
   {
      logfile.WriteLine( "AttackPackCoordinator regrouping to " + regouppos );
      if( debugon )
      {
//         csai.SendTextMsg( "AttackPackCoordinator regrouping to " + regouppos );
      }
      MoveTo( regouppos );
   }

   void MoveTo( TerrainPos pos )
   {
      // check whether we really need to do anything or if order is roughly same as last one
      if( csai.DebugOn )
      {
         drawingUtils.DrawUnit("ARMSOLAR", pos, 0.0f, 50, aicallback.getSkirmishAI().getTeamId(), true, true);
      }
      if( restartedfrompause || 
            pos.GetSquaredDistance( lasttargetpos )
            > ( movetothreshold * movetothreshold ) )
      {
         for( Unit unit : unitsControlled )
         {
            //int deployedid = (int)de.Key;
            //UnitDef unitdef = de.Value as UnitDef;
            giveOrderWrapper.MoveTo(unit, pos );
            //aicallback.GiveOrder( deployedid, new Command( Command.CMD_MOVE, pos.ToDoubleArray() ) );
         }
         restartedfrompause = false;
         lasttargetpos = pos;
      }
   }

   boolean CheckIfPackAlive()
   {
      //if( UnitDefListByDeployedId.size() < MinPackSize )
      // {
      //     if( AttackPackDeadEvent != null )
      //   {
      //     AttackPackDeadEvent();
      // }
      //     return false;
      // }
      return true;
   }

   class UnitInfo
   {
      public Unit unit;
      public TerrainPos pos;
      public UnitDef unitdef;
      public double squareddistance;
      public UnitInfo(){}
      public UnitInfo( Unit unit, TerrainPos pos, UnitDef unitdef, double squareddistance )
      {
         this.unit = unit;
         this.pos = pos;
         this.unitdef = unitdef;
         this.squareddistance = squareddistance;
      }
   }

   UnitInfo[] GetClosestUnits( TerrainPos targetpos, int numclosestunits )
   {
      UnitInfo[] closestunits = new UnitInfo[ numclosestunits ];
      double worsttopfivesquareddistance = 0; // got to get better than this to enter the list
      int numclosestunitsfound = 0;
      for( Unit unit : unitsControlled ) {
         TerrainPos unitpos = unitController.getPos( unit );
         UnitDef unitdef = unit.getDef();
         double unitsquareddistance = unitpos.GetSquaredDistance( targetpos );
         if( numclosestunitsfound < numclosestunits )
         {
            UnitInfo unitinfo = new UnitInfo( unit, unitpos, unitdef, unitsquareddistance );
            InsertIntoArray( closestunits, unitinfo, numclosestunitsfound );
            numclosestunitsfound++;
            worsttopfivesquareddistance = closestunits[ numclosestunitsfound - 1 ].squareddistance;
         }
         else if( unitsquareddistance < worsttopfivesquareddistance )
         {
            UnitInfo unitinfo = new UnitInfo( unit, unitpos, unitdef, unitsquareddistance );
            InsertIntoArray( closestunits, unitinfo, numclosestunits );
            worsttopfivesquareddistance = closestunits[ numclosestunits - 1 ].squareddistance;
         }
      }
      return closestunits;
   }

   // we add it to the bottom, then bubble it up
   void InsertIntoArray( UnitInfo[] closestunits, UnitInfo newunit, int numexistingunits )
   {
      if( numexistingunits < closestunits.length )
      {
         closestunits[ numexistingunits ] = newunit;
         numexistingunits++;
      }
      else
      {
         closestunits[ numexistingunits - 1 ] = newunit;
      }
      // bubble new unit up
      for( int i = numexistingunits - 2; i >= 0; i-- )
      {
         if( closestunits[ i ].squareddistance > closestunits[ i + 1 ].squareddistance )
         {
            UnitInfo swap = closestunits[ i ];
            closestunits[ i ] = closestunits[ i + 1 ];
            closestunits[ i + 1 ] = swap;  
         }
      }
      // debug;
      //  logfile.WriteLine( "AttackPackCoordinator.InsertIntoArray");
      //  for( int i = 0; i < numexistingunits; i++ )
      //   {
      //       logfile.WriteLine(i + ": " + closestunits[ i ].squareddistance );
      //   }
   }

   class GameListenerHandler extends GameAdapter {
      //      int ticks = 0;
      @Override
      public void Tick( int frame )
      {
         //         ticks++;
         //         if( ticks >= 30 )
         //         {
         Recoordinate();

         //            ticks = 0;
         //         }
      }
   }
}