package org.geotools.data.csv;

import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.util.NoSuchElementException;

import org.geotools.data.FeatureWriter;
import org.geotools.data.Query;
import org.geotools.data.store.ContentState;
import org.opengis.feature.simple.SimpleFeature;
import org.opengis.feature.simple.SimpleFeatureType;

import com.csvreader.CsvWriter;
import com.vividsolutions.jts.geom.Point;

// Obviously, WIP...
public class CSVFeatureWriter extends CSVFeatureReader implements FeatureWriter<SimpleFeatureType, SimpleFeature> {

    private CsvWriter csvWriter;
    private File tempFile;
    private SimpleFeature each;
    private boolean append = false;
    private boolean appending = false;  // TODO this is way ugly
    
    public CSVFeatureWriter(ContentState contentState) throws IOException {
        super(contentState);
        this.tempFile = File.createTempFile("cvsDataStore", ".csv");
        this.csvWriter = new CsvWriter(new FileWriter(this.tempFile), ',');
        this.csvWriter.writeRecord(this.reader.getHeaders());
    }

    public CSVFeatureWriter(ContentState contentState, Query query, boolean append) throws IOException {
        this(contentState);
        if (append) {
            this.appending = true;
            while(this.hasNext()) {
                this.each = this.next();
                this.write();
            }
            this.appending = false;
        }
        this.append = append;
    }

    public void remove() throws IOException {
        this.each = null;       // just mark it done which means it will not get written out.  
    }

    @Override
    public boolean hasNext() throws IOException {
        if (this.append) {
            return false;
        }
        return super.hasNext();
    }

    public void write() throws IOException {
        if (this.each == null) {
            return;
        }
        for (int i = 0; i < this.each.getAttributeCount(); i++) {
            Object attr = this.each.getAttribute(i);
            if (attr instanceof Point) {
                Point point = (Point) attr;
                this.csvWriter.write(Double.toString(point.getX()));
                this.csvWriter.write(Double.toString(point.getY()));
            } else {
                this.csvWriter.write(attr.toString());
            }
        }
        this.csvWriter.endRecord();
        this.each = null;       // indicate that it has been written
    }

    @Override
    public SimpleFeature next() throws IOException, IllegalArgumentException, NoSuchElementException {
        if (this.append) {
            this.builder.addAll(new Object[this.state.getEntry().getDataStore().getSchema(this.getFeatureType().getTypeName()).getAttributeCount()]);
            this.each = this.buildFeature();
            return this.each;
        }
        this.checkPendingWrite();
        return this.each = super.next();
    }

    @Override
    public void close() throws IOException {
        if (this.appending) {
            return;
        }
        this.checkPendingWrite();
        super.close();
        this.csvWriter.close();
        ((CSVDataStore) this.state.getEntry().getDataStore()).write(this.tempFile);
    }

    private void checkPendingWrite() throws IOException {
        if (this.each != null) {
            // the previous one was not written, so do it now.
            this.write();
        }
    }
}