package com.ximple.io.dgn7;

import java.nio.ByteOrder;
import java.util.ArrayList;

import org.apache.log4j.Logger;

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

import com.ximple.util.DgnUtility;

/**
 * ArcElement
 *
 * @author Ulysses
 * @version 0.1
 * @since 2006/5/26 下午 06:41:45
 */
public class ArcElement extends Element implements GeometryConverter
{
    private static final Logger logger = Logger.getLogger(ArcElement.class);

    public ArcElement(byte[] raw)
    {
        super(raw);
    }

    public double getStartAngle()
    {
        int angle = (raw[18] & 0x0000ffff) << 16 | (raw[19] & 0x0000ffff);
        return DgnUtility.converIntToRotation(angle);
    }

    public void setStartAngle(double value)
    {
        int angle = DgnUtility.converRotatioToInt(value);

        raw[18] = (short) (angle >>> 16 & 0x0000ffff);
        raw[19] = (short) (angle & 0x0000ffff);
    }

    public double getSweepAngle()
    {
        int angle = (raw[20] & 0x0000ffff) << 16 | (raw[21] & 0x0000ffff);
        if (angle < 0)
            angle = -1 * (angle & 0x7fffffff);

        return DgnUtility.converIntToRotation(angle);
    }

    public void setSweepAngle(double value)
    {
        int angle = DgnUtility.converRotatioToInt(value);
        if (angle < 0)
        {
            angle &= 0x7fffffff;
            angle |= 0x80000000;
        }

        raw[20] = (short) (angle >> 16 & 0x0000ffff);
        raw[21] = (short) (angle & 0x0000ffff);
    }

    public double getPrimary()
    {
        rawBuffer.position(22 * 2);
        ByteOrder bo = rawBuffer.order();
        rawBuffer.order(ByteOrder.BIG_ENDIAN);
        byte[] primary = new byte[8];
        rawBuffer.get(primary);
        rawBuffer.order(bo);
        return DgnUtility.convertDGNToIEEEDouble(primary) / 1000.0;
    }

    public void setPrimary(double value)
    {
        double temp = value * 1000.0;
        short[] primary = DgnUtility.convertIEEEDoubleToDGN(temp);

        System.arraycopy(primary, 0, raw, 22, 4);
    }

    public double getSecondary()
    {
        rawBuffer.position(26 * 2);
        ByteOrder bo = rawBuffer.order();
        rawBuffer.order(ByteOrder.BIG_ENDIAN);
        byte[] secondary = new byte[8];
        rawBuffer.get(secondary);
        rawBuffer.order(bo);
        return DgnUtility.convertDGNToIEEEDouble(secondary) / 1000.0;
    }

    public void setSecondary(double value)
    {
        double temp = value * 1000.0;
        short[] secondary = DgnUtility.convertIEEEDoubleToDGN(temp);

        System.arraycopy(secondary, 0, raw, 26, 4);
    }

    public double getRotationAngle()
    {
        int rotation = (raw[30] << 16 & 0xffff0000);
        rotation |= raw[31] & 0x0000ffff;

        return DgnUtility.converIntToRotation(rotation);
    }

    public void setRotationAngle(double value)
    {
        int angle = DgnUtility.converRotatioToInt(value);

        raw[30] = (short) (angle >> 16 & 0x0000ffff);
        raw[31] = (short) (angle & 0x0000ffff);
    }

    public Coordinate getOrigin()
    {
        rawBuffer.position(32 * 2);
        ByteOrder bo = rawBuffer.order();
        rawBuffer.order(ByteOrder.BIG_ENDIAN);
        byte[] rawValue = new byte[8];

        rawBuffer.get(rawValue); // x
        double dx = DgnUtility.converUnitToCoord(DgnUtility.convertDGNToIEEEDouble(rawValue));

        rawBuffer.get(rawValue); // y
        double dy = DgnUtility.converUnitToCoord(DgnUtility.convertDGNToIEEEDouble(rawValue));

        rawBuffer.order(bo);

        return new Coordinate(dx, dy);
    }

    public void setOrigin(Coordinate value)
    {
        double temp = DgnUtility.converCoordToUnit(value.x);
        short[] x = DgnUtility.convertIEEEDoubleToDGN(temp);

        System.arraycopy(x, 0, raw, 32, 4);
        temp = DgnUtility.converCoordToUnit(value.y);

        short[] y = DgnUtility.convertIEEEDoubleToDGN(temp);

        System.arraycopy(y, 0, raw, 36, 4);
    }

    public Geometry toGeometry(GeometryFactory factory)
    {
        double sweep = getSweepAngle();
        double temp = Math.abs(sweep);
        temp /= 4;
        int pts = (temp < 3) ? 3 : (int) temp;
        return factory.createLineString(convertToLineString(pts));
    }

    private Coordinate[] convertToLineString(int pts)
    {
        ArrayList<Coordinate> result = new ArrayList<Coordinate>();
        double beta = DgnUtility.converRotationToRadian(-getRotationAngle());
        double startAngle = getStartAngle();
        double sweepAngle = getSweepAngle();
        double endAngle = startAngle + sweepAngle;
        double steps = sweepAngle / pts;
        double current;
        if (sweepAngle < 0)
        {
            for (current = startAngle; current > endAngle; current += steps)
            {
                Coordinate pt = computePointOnArcByAngle(beta, current);
                result.add(pt);
            }

        } else
        {
            for (current = startAngle; current < endAngle; current += steps)
            {
                Coordinate pt = computePointOnArcByAngle(beta, current);
                result.add(pt);
            }
        }

        Coordinate pt = computePointOnArcByAngle(beta, endAngle);
        result.add(pt);

        return result.toArray(new Coordinate[result.size()]);
    }

    private Coordinate computePointOnArcByAngle(double beta, double current)
    {
        double sinbeta = Math.sin(beta);
        double cosbeta = Math.cos(beta);
        Coordinate pt = new Coordinate();
        double alpha = DgnUtility.converRotationToRadian(current);
        double sinalpha = Math.sin(alpha);
        double cosalpha = Math.cos(alpha);
        pt.x = getOrigin().x + (getPrimary() * cosalpha * cosbeta -
                getSecondary() * sinalpha * sinbeta);
        pt.y = getOrigin().y + (getPrimary() * cosalpha * sinbeta +
                getSecondary() * sinalpha * cosbeta);
        return pt;
    }

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

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

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

            return instance;
        }

        protected Element createElement(byte[] raw)
        {
            return new ArcElement(raw);
        }
    }
}