Application: gvSIG desktop

package com.iver.cit.gvsig.fmap.drivers;

import java.io.IOException;

import java.io.Reader;

import java.io.StreamTokenizer;

import java.io.StringReader;

import java.util.ArrayList;

import com.iver.cit.gvsig.fmap.core.FGeometry;

import com.iver.cit.gvsig.fmap.core.FMultiPoint2D;

import com.iver.cit.gvsig.fmap.core.FPoint2D;

import com.iver.cit.gvsig.fmap.core.FPolygon2D;

import com.iver.cit.gvsig.fmap.core.FPolyline2D;

import com.iver.cit.gvsig.fmap.core.GeneralPathX;

import com.iver.cit.gvsig.fmap.core.IGeometry;

import com.iver.cit.gvsig.fmap.core.ShapeFactory;

import com.vividsolutions.jts.geom.Coordinate;

import com.vividsolutions.jts.io.ParseException;

/**

 *  Converts a Well-Known Text string to a <code>Geometry</code>.

 * <p>

 *  The <code>WKTReader</code> allows

 *  extracting <code>Geometry</code> objects from either input streams or

 *  internal strings. This allows it to function as a parser to read <code>Geometry</code>

 *  objects from text blocks embedded in other data formats (e.g. XML). <P>

 * <p>

 * The Well-known

 *  Text format is defined in the <A HREF="http://www.opengis.org/techno/specs.htm">

 *  OpenGIS Simple Features Specification for SQL</A> . <P>

 * <p>

 *  <B>Note: </B> There is an inconsistency in the SFS. The WKT grammar states

 *  that <code>MultiPoints</code> are represented by <code>MULTIPOINT ( ( x y), (x y) )</code>

 *  , but the examples show <code>MultiPoint</code>s as <code>MULTIPOINT ( x y, x y )</code>

 *  . Other implementations follow the latter syntax, so JTS will adopt it as

 *  well.

 *

 *  A <code>WKTReader</code> is parameterized by a <code>GeometryFactory</code>

 *  , to allow it to create <code>Geometry</code> objects of the appropriate

 *  implementation. In particular, the <code>GeometryFactory</code> will

 *  determine the <code>PrecisionModel</code> and <code>SRID</code> that is

 *  used. <P>

 *

 *  The <code>WKTReader</code> will convert the input numbers to the precise

 *  internal representation.

 *

 *  Reads non-standard "LINEARRING" tags.

 *

 *@version 1.5

 */

public class WKTParser {

  /**

   * Creates a WKTReader that creates objects using a basic GeometryFactory.

   */

  public WKTParser() {

  }

        /**

     * Converts a Well-known Text representation to a <code>Geometry</code>.

     * 

     * @param wellKnownText

     *            one or more <Geometry Tagged Text>strings (see the OpenGIS

     *            Simple Features Specification) separated by whitespace

     * @return a <code>Geometry</code> specified by <code>wellKnownText</code>

     * @throws ParseException

     *             if a parsing problem occurs

         */

  public IGeometry read(String wellKnownText) throws ParseException {

    StringReader reader = new StringReader(wellKnownText);

    try {

      return read(reader);

    }

    finally {

      reader.close();

    }

  }

  /**

   *  Converts a Well-known Text representation to a <code>Geometry</code>.

   *

   *@param  reader           a Reader which will return a <Geometry Tagged Text>

   *      string (see the OpenGIS Simple Features Specification)

   *@return                  a <code>Geometry</code> read from <code>reader</code>

   *@throws  ParseException  if a parsing problem occurs

   */

  public IGeometry read(Reader reader) throws ParseException {

    StreamTokenizer tokenizer = new StreamTokenizer(reader);

    try {

      return readGeometryTaggedText(tokenizer);

    }

    catch (IOException e) {

      throw new ParseException(e.toString());

    }

  }

  /**

   *  Returns the next array of <code>Coordinate</code>s in the stream.

   *

   *@param  tokenizer        tokenizer over a stream of text in Well-known Text

   *      format. The next element returned by the stream should be "(" (the

   *      beginning of "(x1 y1, x2 y2, ..., xn yn)") or "EMPTY".

   *@return                  the next array of <code>Coordinate</code>s in the

   *      stream, or an empty array if "EMPTY" is the next element returned by

   *      the stream.

   *@throws  IOException     if an I/O error occurs

   *@throws  ParseException  if an unexpected token was encountered

   */

  private Coordinate[] getCoordinates(StreamTokenizer tokenizer)

      throws IOException, ParseException

  {

    String nextToken = getNextEmptyOrOpener(tokenizer);

    if (nextToken.equals("EMPTY")) {

      return new Coordinate[]{};

    }

    ArrayList coordinates = new ArrayList();

    coordinates.add(getPreciseCoordinate(tokenizer));

    nextToken = getNextCloserOrComma(tokenizer);

    while (nextToken.equals(",")) {

      coordinates.add(getPreciseCoordinate(tokenizer));

      nextToken = getNextCloserOrComma(tokenizer);

    }

    Coordinate[] array = new Coordinate[coordinates.size()];

    return (Coordinate[]) coordinates.toArray(array);

  }

  private Coordinate getPreciseCoordinate(StreamTokenizer tokenizer)

      throws IOException, ParseException

  {

    Coordinate coord = new Coordinate();

    coord.x = getNextNumber(tokenizer);

    coord.y = getNextNumber(tokenizer);

    if (isNumberNext(tokenizer)) {

        coord.z = getNextNumber(tokenizer);

    }

    return coord;

  }

  private boolean isNumberNext(StreamTokenizer tokenizer) throws IOException {

      try {

          return tokenizer.nextToken() == StreamTokenizer.TT_NUMBER;

      }

      finally {

          tokenizer.pushBack();

      }

  }

  /**

   *  Returns the next number in the stream.

   *

   *@param  tokenizer        tokenizer over a stream of text in Well-known Text

   *      format. The next token must be a number.

   *@return                  the next number in the stream

   *@throws  ParseException  if the next token is not a number

   *@throws  IOException     if an I/O error occurs

   */

  private double getNextNumber(StreamTokenizer tokenizer) throws IOException,

      ParseException {

    int type = tokenizer.nextToken();

    switch (type) {

      case StreamTokenizer.TT_EOF:

        throw new ParseException("Expected number but encountered end of stream");

      case StreamTokenizer.TT_EOL:

        throw new ParseException("Expected number but encountered end of line");

      case StreamTokenizer.TT_NUMBER:

        return tokenizer.nval;

      case StreamTokenizer.TT_WORD:

        throw new ParseException("Expected number but encountered word: " +

            tokenizer.sval);

      case '(':

        throw new ParseException("Expected number but encountered '('");

      case ')':

        throw new ParseException("Expected number but encountered ')'");

      case ',':

        throw new ParseException("Expected number but encountered ','");

    }

    return 0;

  }

  /**

   *  Returns the next "EMPTY" or "(" in the stream as uppercase text.

   *

   *@param  tokenizer        tokenizer over a stream of text in Well-known Text

   *      format. The next token must be "EMPTY" or "(".

   *@return                  the next "EMPTY" or "(" in the stream as uppercase

   *      text.

   *@throws  ParseException  if the next token is not "EMPTY" or "("

   *@throws  IOException     if an I/O error occurs

   */

  private String getNextEmptyOrOpener(StreamTokenizer tokenizer) throws IOException, ParseException {

    String nextWord = getNextWord(tokenizer);

    if (nextWord.equals("EMPTY") || nextWord.equals("(")) {

      return nextWord;

    }

    throw new ParseException("Expected 'EMPTY' or '(' but encountered '" +

        nextWord + "'");

  }

  /**

   *  Returns the next ")" or "," in the stream.

   *

   *@param  tokenizer        tokenizer over a stream of text in Well-known Text

   *      format. The next token must be ")" or ",".

   *@return                  the next ")" or "," in the stream

   *@throws  ParseException  if the next token is not ")" or ","

   *@throws  IOException     if an I/O error occurs

   */

  private String getNextCloserOrComma(StreamTokenizer tokenizer) throws IOException, ParseException {

    String nextWord = getNextWord(tokenizer);

    if (nextWord.equals(",") || nextWord.equals(")")) {

      return nextWord;

    }

    throw new ParseException("Expected ')' or ',' but encountered '" + nextWord

         + "'");

  }

  /**

   *  Returns the next ")" in the stream.

   *

   *@param  tokenizer        tokenizer over a stream of text in Well-known Text

   *      format. The next token must be ")".

   *@return                  the next ")" in the stream

   *@throws  ParseException  if the next token is not ")"

   *@throws  IOException     if an I/O error occurs

   */

  private String getNextCloser(StreamTokenizer tokenizer) throws IOException, ParseException {

    String nextWord = getNextWord(tokenizer);

    if (nextWord.equals(")")) {

      return nextWord;

    }

    throw new ParseException("Expected ')' but encountered '" + nextWord + "'");

  }

  /**

   *  Returns the next word in the stream as uppercase text.

   *

   *@param  tokenizer        tokenizer over a stream of text in Well-known Text

   *      format. The next token must be a word.

   *@return                  the next word in the stream as uppercase text

   *@throws  ParseException  if the next token is not a word

   *@throws  IOException     if an I/O error occurs

   */

  private String getNextWord(StreamTokenizer tokenizer) throws IOException, ParseException {

    int type = tokenizer.nextToken();

    switch (type) {

      case StreamTokenizer.TT_EOF:

        throw new ParseException("Expected word but encountered end of stream");

      case StreamTokenizer.TT_EOL:

        throw new ParseException("Expected word but encountered end of line");

      case StreamTokenizer.TT_NUMBER:

        throw new ParseException("Expected word but encountered number: " +

            tokenizer.nval);

      case StreamTokenizer.TT_WORD:

        return tokenizer.sval.toUpperCase();

      case '(':

        return "(";

      case ')':

        return ")";

      case ',':

        return ",";

    }

    // //assert.shouldNeverReachHere("Encountered unexpected StreamTokenizer type: " + type);

    return null;

  }

  /**

   *  Creates a <code>Geometry</code> using the next token in the stream.

   *

   *@param  tokenizer        tokenizer over a stream of text in Well-known Text

   *      format. The next tokens must form a <Geometry Tagged Text>.

   *@return                  a <code>Geometry</code> specified by the next token

   *      in the stream

   *@throws  ParseException  if the coordinates used to create a <code>Polygon</code>

   *      shell and holes do not form closed linestrings, or if an unexpected

   *      token was encountered

   *@throws  IOException     if an I/O error occurs

   */

  private IGeometry readGeometryTaggedText(StreamTokenizer tokenizer) throws IOException, ParseException {

    String type = getNextWord(tokenizer);

    if (type.equals("POINT")) {

      return readPointText(tokenizer);

    }

    else if (type.equals("LINESTRING")) {

      return readLineStringText(tokenizer);

    }

    else if (type.equals("LINEARRING")) {

      return readLinearRingText(tokenizer);

    }

    else if (type.equals("POLYGON")) {

      return readPolygonText(tokenizer);

    }

    else if (type.equals("MULTIPOINT")) {

      return readMultiPointText(tokenizer);

    }

    else if (type.equals("MULTILINESTRING")) {

      return readMultiLineStringText(tokenizer);

    }

    else if (type.equals("MULTIPOLYGON")) {

      return readMultiPolygonText(tokenizer);

    }

    /* else if (type.equals("GEOMETRYCOLLECTION")) {

      return readGeometryCollectionText(tokenizer);

    } */

    System.err.println("Unknown type: " + type);

    throw new ParseException("Unknown type: " + type);

  }

  /**

   *  Creates a <code>Point</code> using the next token in the stream.

   *

   *@param  tokenizer        tokenizer over a stream of text in Well-known Text

   *      format. The next tokens must form a <Point Text>.

   *@return                  a <code>Point</code> specified by the next token in

   *      the stream

   *@throws  IOException     if an I/O error occurs

   *@throws  ParseException  if an unexpected token was encountered

   */

  private FGeometry readPointText(StreamTokenizer tokenizer) throws IOException, ParseException {

    String nextToken = getNextEmptyOrOpener(tokenizer);

    if (nextToken.equals("EMPTY")) {

      return null;

    }

    Coordinate c = getPreciseCoordinate(tokenizer);

    FPoint2D point = new FPoint2D(c.x, c.y );

    getNextCloser(tokenizer);

    return ShapeFactory.createGeometry(point);

  }

  /**

   *  Creates a <code>LineString</code> using the next token in the stream.

   *

   *@param  tokenizer        tokenizer over a stream of text in Well-known Text

   *      format. The next tokens must form a <LineString Text>.

   *@return                  a <code>LineString</code> specified by the next

   *      token in the stream

   *@throws  IOException     if an I/O error occurs

   *@throws  ParseException  if an unexpected token was encountered

   */

  private FGeometry readLineStringText(StreamTokenizer tokenizer) throws IOException, ParseException {

      Coordinate[] arrayC = getCoordinates(tokenizer);

      GeneralPathX gp = new GeneralPathX();

      gp.moveTo(arrayC[0].x,arrayC[0].y);

      for (int i=1;i < arrayC.length; i++)

      {

          gp.lineTo(arrayC[i].x, arrayC[i].y);

      }

    return ShapeFactory.createGeometry(new FPolyline2D(gp));

  }

  /**

   *  Creates a <code>LinearRing</code> using the next token in the stream.

   *

   *@param  tokenizer        tokenizer over a stream of text in Well-known Text

   *      format. The next tokens must form a <LineString Text>.

   *@return                  a <code>LinearRing</code> specified by the next

   *      token in the stream

   *@throws  IOException     if an I/O error occurs

   *@throws  ParseException  if the coordinates used to create the <code>LinearRing</code>

   *      do not form a closed linestring, or if an unexpected token was

   *      encountered

   */

  private FGeometry readLinearRingText(StreamTokenizer tokenizer)

    throws IOException, ParseException

  {

      Coordinate[] arrayC = getCoordinates(tokenizer);

      GeneralPathX gp = new GeneralPathX();

      gp.moveTo(arrayC[0].x, arrayC[0].y);

      for (int i=1;i < arrayC.length; i++)

      {

          gp.lineTo(arrayC[i].x, arrayC[i].y);

      }

      return ShapeFactory.createGeometry(new FPolygon2D(gp));

  }

  /**

   *  Creates a <code>MultiPoint</code> using the next token in the stream.

   *

   *@param  tokenizer        tokenizer over a stream of text in Well-known Text

   *      format. The next tokens must form a <MultiPoint Text>.

   *@return                  a <code>MultiPoint</code> specified by the next

   *      token in the stream

   *@throws  IOException     if an I/O error occurs

   *@throws  ParseException  if an unexpected token was encountered

   */

  private IGeometry readMultiPointText(StreamTokenizer tokenizer) throws IOException, ParseException {

    Coordinate[] coords = getCoordinates(tokenizer);

    double[] x = new double[coords.length];

    double[] y = new double[coords.length];

    for (int i=0; i < coords.length; i++)

    {

        x[i] = coords[i].x;

        y[i] = coords[i].y;

    }

    FMultiPoint2D multi = new FMultiPoint2D(x, y);

    return multi;

  }

  /**

   *  Creates a <code>Polygon</code> using the next token in the stream.

   *

   *@param  tokenizer        tokenizer over a stream of text in Well-known Text

   *      format. The next tokens must form a <Polygon Text>.

   *@return                  a <code>Polygon</code> specified by the next token

   *      in the stream

   *@throws  ParseException  if the coordinates used to create the <code>Polygon</code>

   *      shell and holes do not form closed linestrings, or if an unexpected

   *      token was encountered.

   *@throws  IOException     if an I/O error occurs

   */

  private FGeometry readPolygonText(StreamTokenizer tokenizer) throws IOException, ParseException {

    String nextToken = getNextEmptyOrOpener(tokenizer);

    if (nextToken.equals("EMPTY")) {

        return null;

    }

    ArrayList holes = new ArrayList();

    FGeometry shell = readLinearRingText(tokenizer);

    nextToken = getNextCloserOrComma(tokenizer);

    while (nextToken.equals(",")) {

      FGeometry hole = readLinearRingText(tokenizer);

      holes.add(hole);

      nextToken = getNextCloserOrComma(tokenizer);

    }

    // LinearRing[] array = new LinearRing[holes.size()];

    return shell; //geometryFactory.createPolygon(shell, (LinearRing[]) holes.toArray(array));

  }

  /**

   *  Creates a <code>MultiLineString</code> using the next token in the stream.

   *

   *@param  tokenizer        tokenizer over a stream of text in Well-known Text

   *      format. The next tokens must form a <MultiLineString Text>.

   *@return                  a <code>MultiLineString</code> specified by the

   *      next token in the stream

   *@throws  IOException     if an I/O error occurs

   *@throws  ParseException  if an unexpected token was encountered

   */

  private FGeometry readMultiLineStringText(StreamTokenizer tokenizer) throws IOException, ParseException {

      // TODO: HACER ESTO BIEN, CON UN GENERAL PATH

    String nextToken = getNextEmptyOrOpener(tokenizer);

    if (nextToken.equals("EMPTY")) {

      return null;

    }

    ArrayList lineStrings = new ArrayList();

    FGeometry lineString = readLineStringText(tokenizer);

    lineStrings.add(lineString);

    nextToken = getNextCloserOrComma(tokenizer);

    while (nextToken.equals(",")) {

      lineString = readLineStringText(tokenizer);

      lineStrings.add(lineString);

      nextToken = getNextCloserOrComma(tokenizer);

    } 

    // LineString[] array = new LineString[lineStrings.size()];

    return lineString; // geometryFactory.createMultiLineString((LineString[]) lineStrings.toArray(array));

  }

  /**

   *  Creates a <code>MultiPolygon</code> using the next token in the stream.

   *

   *@param  tokenizer        tokenizer over a stream of text in Well-known Text

   *      format. The next tokens must form a <MultiPolygon Text>.

   *@return                  a <code>MultiPolygon</code> specified by the next

   *      token in the stream, or if if the coordinates used to create the

   *      <code>Polygon</code> shells and holes do not form closed linestrings.

   *@throws  IOException     if an I/O error occurs

   *@throws  ParseException  if an unexpected token was encountered

   */

  // TODO:

  private IGeometry readMultiPolygonText(StreamTokenizer tokenizer) throws IOException, ParseException {

    String nextToken = getNextEmptyOrOpener(tokenizer);

    if (nextToken.equals("EMPTY")) {

      return null;

    }

    ArrayList polygons = new ArrayList();

    FGeometry polygon = readPolygonText(tokenizer);

    /* polygons.add(polygon);

    nextToken = getNextCloserOrComma(tokenizer);

    while (nextToken.equals(",")) {

      polygon = readPolygonText(tokenizer);

      polygons.add(polygon);

      nextToken = getNextCloserOrComma(tokenizer);

    } */

    // Polygon[] array = new Polygon[polygons.size()];

    return polygon; //geometryFactory.createMultiPolygon((Polygon[]) polygons.toArray(array));

  } 

  /**

   *  Creates a <code>GeometryCollection</code> using the next token in the

   *  stream.

   *

   *@param  tokenizer        tokenizer over a stream of text in Well-known Text

   *      format. The next tokens must form a <GeometryCollection Text>.

   *@return                  a <code>GeometryCollection</code> specified by the

   *      next token in the stream

   *@throws  ParseException  if the coordinates used to create a <code>Polygon</code>

   *      shell and holes do not form closed linestrings, or if an unexpected

   *      token was encountered

   *@throws  IOException     if an I/O error occurs

   */

  // TODO:

  /* private GeometryCollection readGeometryCollectionText(StreamTokenizer tokenizer) throws IOException, ParseException {

    String nextToken = getNextEmptyOrOpener(tokenizer);

    if (nextToken.equals("EMPTY")) {

      return geometryFactory.createGeometryCollection(new Geometry[]{});

    }

    ArrayList geometries = new ArrayList();

    Geometry geometry = readGeometryTaggedText(tokenizer);

    geometries.add(geometry);

    nextToken = getNextCloserOrComma(tokenizer);

    while (nextToken.equals(",")) {

      geometry = readGeometryTaggedText(tokenizer);

      geometries.add(geometry);

      nextToken = getNextCloserOrComma(tokenizer);

    }

    Geometry[] array = new Geometry[geometries.size()];

    return geometryFactory.createGeometryCollection((Geometry[]) geometries.toArray(array));

  } */

}