--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/flys-artifacts/src/main/java/de/intevation/flys/exports/WstWriter.java	Tue May 17 16:31:07 2011 +0000
@@ -0,0 +1,187 @@
+package de.intevation.flys.exports;
+
+import java.io.BufferedWriter;
+import java.io.OutputStream;
+import java.io.OutputStreamWriter;
+import java.io.PrintWriter;
+
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.Locale;
+import java.util.Map;
+import java.util.TreeMap;
+
+import org.apache.log4j.Logger;
+
+import de.intevation.flys.artifacts.model.WstLine;
+
+
+/**
+ * A writer that creates WSTs.
+ *
+ * @author <a href="mailto:ingo.weinzierl@intevation.de">Ingo Weinzierl</a>
+ */
+public class WstWriter {
+
+    /** The logger used in this class.*/
+    private static Logger logger = Logger.getLogger(WstWriter.class);
+
+
+    /** The default unit that is written into the header of the WST.*/
+    public static final String DEFAULT_UNIT = "Wassserstand [NN + m]";
+
+
+    /** The lines that need to be included for the export.*/
+    protected Map<Double, WstLine> lines;
+
+    /** The locale used to format the values.*/
+    protected Locale locale;
+
+    /** The number of discharge columns.*/
+    protected int cols;
+
+    /** The last Q values.*/
+    protected double[] qs;
+
+
+
+    /**
+     * This constructor creates a new WstWriter with an OutputStream and a
+     * number of Q columns.
+     *
+     * @param out The output stream where the WST is written to.
+     * @param cols The number of columns of the resulting WST.
+     */
+    public WstWriter(int cols) {
+        this.cols   = cols;
+        this.qs     = new double[cols];
+        this.locale = Locale.US;
+        this.lines  = new HashMap<Double, WstLine>();
+
+    }
+
+
+    /**
+     * This method is used to create the WST from the data that has been
+     * inserted using add(double[]) before.
+     */
+    public void write(OutputStream out) {
+        logger.info("WstWriter.write");
+
+        PrintWriter writer = new PrintWriter(
+            new BufferedWriter(
+                new OutputStreamWriter(out)));
+
+        writeHeader(writer);
+
+        Collection<WstLine> collection = new TreeMap(lines).values();
+
+        for (WstLine line: collection) {
+            writeWLine(writer, line);
+        }
+
+        writer.flush();
+        writer.close();
+    }
+
+
+    /**
+     * This method is used to add a new line to the WST.
+     *
+     * @param wqkms A 3dim double array with [W,Q, KM].
+     */
+    public void add(double[] wqkms) {
+        Double km = wqkms[2];
+
+        WstLine line = lines.get(km);
+
+        if (line == null) {
+            line = new WstLine(km.doubleValue());
+            lines.put(km, line);
+        }
+
+        line.add(wqkms[0], wqkms[1]);
+    }
+
+
+    /**
+     * This method writes the header of the WST.
+     *
+     * @param writer The PrintWriter that creates the output.
+     */
+    protected void writeHeader(PrintWriter writer) {
+        logger.debug("WstWriter.writeHeader");
+
+        writer.println(cols);
+
+        // TODO WRITE DISCHARGE COLUMNS
+
+        writer.write("*   KM     ");
+        writer.write(DEFAULT_UNIT);
+        writer.println();
+    }
+
+
+    /**
+     * This method writes a line with W values and a certain kilometer.
+     *
+     * @param writer The PrintWriter that is used to create the output.
+     * @param line The WstLine that should be written to the output.
+     */
+    protected void writeWLine(PrintWriter writer, WstLine line) {
+        double   km  = line.getKm();
+        double[] qs  = line.getQs();
+        int      num = line.getSize();
+
+        if (dischargesChanged(qs)) {
+            writeQLine(writer, qs);
+        }
+
+        writer.printf(locale, "%8.3f", km);
+
+        for (int i = 0; i < num; i++) {
+            writer.printf(locale, "%9.2f", line.getW(i));
+        }
+
+        writer.println();
+    }
+
+
+    /**
+     * Writes a discharge line (Q values) into a WST.
+     *
+     * @param qs the Q values for the next range.
+     */
+    protected void writeQLine(PrintWriter writer, double[] qs) {
+        writer.write("*\u001f      ");
+
+        for (int i = 0; i < cols; i++) {
+            this.qs[i] = qs[i];
+
+            writer.printf(locale, "%9.2f", qs[i]);
+        }
+
+        writer.println();
+    }
+
+
+    /**
+     * This method determines if a Q has changed from the last line to the
+     * current one.
+     *
+     * @param newQs The Q values of the next line.
+     *
+     * @return true, if a Q value have changed, otherwise false.
+     */
+    protected boolean dischargesChanged(double[] newQs) {
+        // XXX maybe there is a way to do this faster
+        for (int i = 0; i < cols; i++) {
+            if (Math.abs(newQs[i] - qs[i]) >= 0.001) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+}
+// vim:set ts=4 sw=4 si et sta sts=4 fenc=utf8 :