/**
 * Container for an osm node (pre-pocessor version)
 *
 * @author ab
 */
package btools.mapcreator;

import java.io.IOException;
import java.util.ArrayList;
import java.util.HashMap;

import btools.codec.MicroCache;
import btools.codec.MicroCache2;

public class OsmNodeP extends OsmLinkP
{
  /**
   * The latitude
   */
  public int ilat;

  /**
   * The longitude
   */
  public int ilon;

  /**
   * The elevation
   */
  public short selev;

  public final static int NO_BRIDGE_BIT = 1;
  public final static int NO_TUNNEL_BIT = 2;
  public final static int BORDER_BIT = 4;
  public final static int TRAFFIC_BIT = 8;
  public final static int ANY_WAY_BIT = 16;
  public final static int MULTI_WAY_BIT = 32;
  public final static int DP_SURVIVOR_BIT = 64;

  public byte bits = 0;

  // interface OsmPos
  public int getILat()
  {
    return ilat;
  }

  public int getILon()
  {
    return ilon;
  }

  public short getSElev()
  {
    // if all bridge or all tunnel, elevation=no-data
    return ( bits & NO_BRIDGE_BIT ) == 0 || ( bits & NO_TUNNEL_BIT ) == 0 ? Short.MIN_VALUE : selev;
  }

  public double getElev()
  {
    return selev / 4.;
  }

  // populate and return the inherited link, if available,
  // else create a new one
  public OsmLinkP createLink( OsmNodeP source )
  {
    if ( sourceNode == null && targetNode == null )
    {
      // inherited instance is available, use this
      sourceNode = source;
      targetNode = this;
      source.addLink( this );
      return this;
    }
    OsmLinkP link = new OsmLinkP( source, this );
    addLink( link );
    source.addLink( link );
    return link;
  }

  // memory-squeezing-hack: OsmLinkP's "previous" also used as firstlink..

  public void addLink( OsmLinkP link )
  {
    link.setNext( previous, this );
    previous = link;
  }

  public OsmLinkP getFirstLink()
  {
    return sourceNode == null && targetNode == null ? previous : this;
  }

  public byte[] getNodeDecsription()
  {
    return null;
  }

  public RestrictionData getFirstRestriction()
  {
    return null;
  }

  public void writeNodeData( MicroCache mc ) throws IOException
  {
    boolean valid = true;
    if ( mc instanceof MicroCache2 )
    {
      valid = writeNodeData2( (MicroCache2) mc );
    }
    else
      throw new IllegalArgumentException( "unknown cache version: " + mc.getClass() );
    if ( valid )
    {
      mc.finishNode( getIdFromPos() );
    }
    else
    {
      mc.discardNode();
    }
  }

  public void checkDuplicateTargets()
  {
    HashMap<OsmNodeP,OsmLinkP> targets = new HashMap<OsmNodeP,OsmLinkP>();

    for ( OsmLinkP link0 = getFirstLink(); link0 != null; link0 = link0.getNext( this ) )
    {
      OsmLinkP link = link0;
      OsmNodeP origin = this;
      OsmNodeP target = null;

      // first pass just to see if that link is consistent
      while (link != null)
      {
        target = link.getTarget( origin );
        if ( !target.isTransferNode() )
        {
          break;
        }
        // next link is the one (of two), does does'nt point back
        for ( link = target.getFirstLink(); link != null; link = link.getNext( target ) )
        {
          if ( link.getTarget( target ) != origin )
            break;
        }
        origin = target;
      }
      if ( link == null ) continue;
      OsmLinkP oldLink = targets.put( target, link0 );
      if ( oldLink != null )
      {
        unifyLink( oldLink );
        unifyLink( link0 );
      }
    }
  }

  private void unifyLink( OsmLinkP link )
  {
    if ( link.isReverse( this ) ) return;
    OsmNodeP target = link.getTarget( this );
    if ( target.isTransferNode() )
    {
      target.incWayCount();
    }
  }

  public boolean writeNodeData2( MicroCache2 mc ) throws IOException
  {
    boolean hasLinks = false;
    
    // write turn restrictions
    RestrictionData r = getFirstRestriction();
    while( r != null )
    {
      if ( r.fromLon != 0 && r.toLon != 0 )
      {
        mc.writeBoolean( true ); // restriction follows
        mc.writeShort( r.exceptions );
        mc.writeBoolean( r.isPositive );
        mc.writeInt( r.fromLon );
        mc.writeInt( r.fromLat );
        mc.writeInt( r.toLon );
        mc.writeInt( r.toLat );
      }
      r = r.next;
    }
    mc.writeBoolean( false ); // end restritions

    mc.writeShort( getSElev() );
    mc.writeVarBytes( getNodeDecsription() );

    // buffer internal reverse links
    ArrayList<OsmNodeP> internalReverse = new ArrayList<OsmNodeP>();

    for ( OsmLinkP link0 = getFirstLink(); link0 != null; link0 = link0.getNext( this ) )
    {
      OsmLinkP link = link0;
      OsmNodeP origin = this;
      OsmNodeP target = null;

      ArrayList<OsmNodeP> linkNodes = new ArrayList<OsmNodeP>();
      linkNodes.add( this );

      // first pass just to see if that link is consistent
      while (link != null)
      {
        target = link.getTarget( origin );
        linkNodes.add( target );

        if ( !target.isTransferNode() )
        {
          break;
        }
        // next link is the one (of two), does does'nt point back
        for ( link = target.getFirstLink(); link != null; link = link.getNext( target ) )
        {
          if ( link.getTarget( target ) != origin )
            break;
        }

        if ( link != null && link.descriptionBitmap != link0.descriptionBitmap )
        {
          throw new IllegalArgumentException( "assertion failed: description change along transfer nodes" );
        }

        origin = target;
      }
      if ( link == null )
        continue; // dead end
      if ( target == this )
        continue; // self-ref
      hasLinks = true;

      // internal reverse links later
      boolean isReverse = link0.isReverse( this );
      if ( isReverse )
      {
        if ( mc.isInternal( target.ilon, target.ilat ) )
        {
          internalReverse.add( target );
          continue;
        }
      }

      // write link data
      int sizeoffset = mc.writeSizePlaceHolder();
      mc.writeVarLengthSigned( target.ilon - ilon );
      mc.writeVarLengthSigned( target.ilat - ilat );
      mc.writeModeAndDesc( isReverse, link0.descriptionBitmap );
      if ( !isReverse && linkNodes.size() > 2 ) // write geometry for forward links only
      {
        DPFilter.doDPFilter( linkNodes, 0, linkNodes.size()-1 );
        origin = this;
        for( int i=1; i<linkNodes.size()-1; i++ )
        {
          OsmNodeP tranferNode = linkNodes.get(i);
          if ( ( tranferNode.bits & OsmNodeP.DP_SURVIVOR_BIT ) != 0 )
          {
            mc.writeVarLengthSigned( tranferNode.ilon - origin.ilon );
            mc.writeVarLengthSigned( tranferNode.ilat - origin.ilat );
            mc.writeVarLengthSigned( tranferNode.getSElev() - origin.getSElev() );
            origin = tranferNode;
          }
        }
      }
      mc.injectSize( sizeoffset );
    }

    while (internalReverse.size() > 0)
    {
      int nextIdx = 0;
      if ( internalReverse.size() > 1 )
      {
        int max32 = Integer.MIN_VALUE;
        for ( int i = 0; i < internalReverse.size(); i++ )
        {
          int id32 = mc.shrinkId( internalReverse.get( i ).getIdFromPos() );
          if ( id32 > max32 )
          {
            max32 = id32;
            nextIdx = i;
          }
        }
      }
      OsmNodeP target = internalReverse.remove( nextIdx );
      int sizeoffset = mc.writeSizePlaceHolder();
      mc.writeVarLengthSigned( target.ilon - ilon );
      mc.writeVarLengthSigned( target.ilat - ilat );
      mc.writeModeAndDesc( true, null );
      mc.injectSize( sizeoffset );
    }
    return hasLinks;
  }

  public String toString2()
  {
    return ( ilon - 180000000 ) + "_" + ( ilat - 90000000 ) + "_" + ( selev / 4 );
  }

  public long getIdFromPos()
  {
    return ( (long) ilon ) << 32 | ilat;
  }

  public boolean isBorderNode()
  {
    return ( bits & BORDER_BIT ) != 0;
  }

  public boolean hasTraffic()
  {
    return ( bits & TRAFFIC_BIT ) != 0;
  }

  /**
   * Not really count the ways, just detect if more than one
   */
  public void incWayCount()
  {
    if ( ( bits & ANY_WAY_BIT ) != 0 )
    {
      bits |= MULTI_WAY_BIT;
    }
    bits |= ANY_WAY_BIT;
  }

  public boolean isTransferNode()
  {
    return ( bits & BORDER_BIT ) == 0 && ( bits & MULTI_WAY_BIT ) == 0 && _linkCnt() == 2;
  }

  private int _linkCnt()
  {
    int cnt = 0;

    for ( OsmLinkP link = getFirstLink(); link != null; link = link.getNext( this ) )
    {
      cnt++;
    }
    return cnt;
  }

}