package com.ximple.io.dgn7;

//~--- non-JDK imports --------------------------------------------------------

import com.vividsolutions.jts.geom.Coordinate;
import com.vividsolutions.jts.geom.Geometry;
import com.vividsolutions.jts.geom.GeometryFactory;

/**
 * LineStringElement
 *
 * @author Ulysses
 * @version 0.1
 * @since 2006/5/18 下午 02:48:58
 */
public class LineStringElement extends Element implements GeometryConverter
{
    public LineStringElement(short[] raw)
    {
        super(raw);
    }

    public Coordinate getCentroid(double dTolerance)
    {
        return null;
    }

    public Coordinate getEndPoint()
    {
        return new Coordinate(getX(getVerticeSize() - 1), getY(getVerticeSize() - 1));
    }

    public Coordinate getNormal()
    {
        return null;
    }

    public Coordinate getOrigin()
    {
        return null;
    }

    public Coordinate getStartPoint()
    {
        return new Coordinate(getX(0), getY(0));
    }

    public Coordinate getVertex(int index)
    {
        return (index == 0)
               ? getStartPoint()
               : getEndPoint();
    }

    public int getVerticeSize()
    {
        return raw[18] & 0x0000ffff;
    }

    public double getLength()
    {
        double       result = 0.0;
        Coordinate[] vset   = getVertices();

        for (int i = 1; i < getVerticeSize(); i++)
        {
            Coordinate p1 = vset[i - 1];
            Coordinate p2 = vset[i];

            result += Utility.getLength(p1.x, p1.y, p2.x, p2.y);
        }

        return result;
    }

    public Coordinate pointAtDistance(double dDistance, double dTolerance)
    {
        return null;
    }

    public Coordinate[] getVertices()
    {
        Coordinate[] result = new Coordinate[getVerticeSize()];

        for (int i = 0; i < getVerticeSize(); i++)
        {
            result[i] = new Coordinate(getX(i), getY(i));
        }

        return result;
    }

    public Geometry toGeometry(GeometryFactory factory)
    {
        return factory.createLineString(getVertices());
    }

    protected double getX(int index)
    {
        if ((index < 0) || (index > getVerticeSize()))
        {
            return -1;
        }

        int x = (int) ((raw[19 + (4 * index)] << 16) & 0xffff0000);

        x += (int) (raw[20 + (4 * index)] & 0x0000ffff);

        return Utility.converUnitToCoord(x);
    }

    protected void setX(int index, double dx)
    {
        int newVal = Utility.converCoordToUnit(dx);

        raw[19 + (4 * index)] = (short) (newVal >> 16 & 0x0000ffff);
        raw[20 + (4 * index)] = (short) (newVal & 0x0000ffff);
    }

    protected double getY(int index)
    {
        if ((index < 0) || (index > getVerticeSize()))
        {
            return -1;
        }

        int y = (int) ((raw[21 + (4 * index)] << 16) & 0xffff0000);

        y = y + (int) (raw[22 + (4 * index)] & 0x0000ffff);

        return Utility.converUnitToCoord(y);
    }

    protected void setY(int index, double dy)
    {
        int newVal = Utility.converCoordToUnit(dy);

        raw[21 + (4 * index)] = (short) ((newVal >> 16) & 0x0000ffff);
        raw[22 + (4 * index)] = (short) (newVal & 0x0000ffff);
    }

    public static class ElementHandler extends Element.ElementHandler
    {
        private static ElementHandler instance = null;

        public ElementHandler()
        {
            super(ElementType.LINESTRING);
        }

        public static IElementHandler getInstance()
        {
            if (instance == null)
            {
                instance = new ElementHandler();
            }

            return instance;
        }

        protected Element createElement(short[] raw)
        {
            return new LineStringElement(raw);
        }
    }
}