/*
 *
 * This file is part of the iText (R) project.
    Copyright (c) 1998-2017 iText Group NV
 * Authors: Bruno Lowagie, Paulo Soares, et al.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License version 3
 * as published by the Free Software Foundation with the addition of the
 * following permission added to Section 15 as permitted in Section 7(a):
 * FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY
 * ITEXT GROUP. ITEXT GROUP DISCLAIMS THE WARRANTY OF NON INFRINGEMENT
 * OF THIRD PARTY RIGHTS
 *
 * This program is distributed in the hope that it will be useful, but
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
 * or FITNESS FOR A PARTICULAR PURPOSE.
 * See the GNU Affero General Public License for more details.
 * You should have received a copy of the GNU Affero General Public License
 * along with this program; if not, see http://www.gnu.org/licenses or write to
 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA, 02110-1301 USA, or download the license from the following URL:
 * http://itextpdf.com/terms-of-use/
 *
 * The interactive user interfaces in modified source and object code versions
 * of this program must display Appropriate Legal Notices, as required under
 * Section 5 of the GNU Affero General Public License.
 *
 * In accordance with Section 7(b) of the GNU Affero General Public License,
 * a covered work must retain the producer line in every PDF that is created
 * or manipulated using iText.
 *
 * You can be released from the requirements of the license by purchasing
 * a commercial license. Buying such a license is mandatory as soon as you
 * develop commercial activities involving the iText software without
 * disclosing the source code of your own applications.
 * These activities include: offering paid services to customers as an ASP,
 * serving PDFs on the fly in a web application, shipping iText with a closed
 * source product.
 *
 * For more information, please contact iText Software Corp. at this
 * address: sales@itextpdf.com
 */
package com.itextpdf.text.pdf;

import com.itextpdf.text.DocWriter;
import com.itextpdf.text.ExceptionConverter;
import com.itextpdf.text.Image;
import com.itextpdf.text.log.Counter;
import com.itextpdf.text.log.CounterFactory;
import com.itextpdf.text.pdf.AcroFields.Item;

import java.io.IOException;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Map;
import java.util.StringTokenizer;

/** Writes an FDF form.
 * @author Paulo Soares
 */
public class FdfWriter {
    private static final byte[] HEADER_FDF = DocWriter.getISOBytes("%FDF-1.4\n%\u00e2\u00e3\u00cf\u00d3\n");
    HashMap<String, Object> fields = new HashMap<String, Object>();
    Wrt wrt = null;

    /** The PDF file associated with the FDF. */
    private String file;
    private String statusMessage;

    /** Creates a new FdfWriter. */
    public FdfWriter() {
    }

    public FdfWriter(OutputStream os) throws IOException {
        wrt = new Wrt(os, this);
    }

    /** Writes the content to a stream.
     * @param os the stream
     * @throws IOException on error
     */
    public void writeTo(OutputStream os) throws IOException {
        if (wrt == null)
            wrt = new Wrt(os, this);
        wrt.write();
    }

    public void write() throws IOException {
        wrt.write();
    }

    public String getStatusMessage() {
        return statusMessage;
    }

    public void setStatusMessage(String statusMessage) {
        this.statusMessage = statusMessage;
    }

    @SuppressWarnings("unchecked")
    boolean setField(String field, PdfObject value) {
        HashMap<String, Object> map = fields;
        StringTokenizer tk = new StringTokenizer(field, ".");
        if (!tk.hasMoreTokens())
            return false;
        while (true) {
            String s = tk.nextToken();
            Object obj = map.get(s);
            if (tk.hasMoreTokens()) {
                if (obj == null) {
                    obj = new HashMap<String, Object>();
                    map.put(s, obj);
                    map = (HashMap<String, Object>)obj;
                    continue;
                }
                else if (obj instanceof HashMap)
                    map = (HashMap<String, Object>)obj;
                else
                    return false;
            }
            else {
                if (!(obj instanceof HashMap)) {
                    map.put(s, value);
                    return true;
                }
                else
                    return false;
            }
        }
    }

    @SuppressWarnings("unchecked")
    void iterateFields(HashMap<String, Object> values, HashMap<String, Object> map, String name) {
        for (Map.Entry<String, Object> entry: map.entrySet()) {
            String s = entry.getKey();
            Object obj = entry.getValue();
            if (obj instanceof HashMap)
                iterateFields(values, (HashMap<String, Object>)obj, name + "." + s);
            else
                values.put((name + "." + s).substring(1), obj);
        }
    }

    /** Removes the field value.
     * @param field the field name
     * @return <CODE>true</CODE> if the field was found and removed,
     * <CODE>false</CODE> otherwise
     */
    @SuppressWarnings("unchecked")
    public boolean removeField(String field) {
        HashMap<String, Object> map = fields;
        StringTokenizer tk = new StringTokenizer(field, ".");
        if (!tk.hasMoreTokens())
            return false;
        ArrayList<Object> hist = new ArrayList<Object>();
        while (true) {
            String s = tk.nextToken();
            Object obj = map.get(s);
            if (obj == null)
                return false;
            hist.add(map);
            hist.add(s);
            if (tk.hasMoreTokens()) {
                if (obj instanceof HashMap)
                    map = (HashMap<String, Object>)obj;
                else
                    return false;
            }
            else {
                if (obj instanceof HashMap)
                    return false;
                else
                    break;
            }
        }
        for (int k = hist.size() - 2; k >= 0; k -= 2) {
            map = (HashMap<String, Object>)hist.get(k);
            String s = (String)hist.get(k + 1);
            map.remove(s);
            if (!map.isEmpty())
                break;
        }
        return true;
    }

    /** Gets all the fields. The map is keyed by the fully qualified
     * field name and the values are <CODE>PdfObject</CODE>.
     * @return a map with all the fields
     */
    public HashMap<String, Object> getFields() {
        HashMap<String, Object> values = new HashMap<String, Object>();
        iterateFields(values, fields, "");
        return values;
    }

    /** Gets the field value.
     * @param field the field name
     * @return the field value or <CODE>null</CODE> if not found
     */
    @SuppressWarnings("unchecked")
    public String getField(String field) {
        HashMap<String, Object> map = fields;
        StringTokenizer tk = new StringTokenizer(field, ".");
        if (!tk.hasMoreTokens())
            return null;
        while (true) {
            String s = tk.nextToken();
            Object obj = map.get(s);
            if (obj == null)
                return null;
            if (tk.hasMoreTokens()) {
                if (obj instanceof HashMap)
                    map = (HashMap<String, Object>)obj;
                else
                    return null;
            }
            else {
                if (obj instanceof HashMap)
                    return null;
                else {
                    if (((PdfObject)obj).isString())
                        return ((PdfString)obj).toUnicodeString();
                    else
                        return PdfName.decodeName(obj.toString());
                }
            }
        }
    }

    /** Sets the field value as a name.
     * @param field the fully qualified field name
     * @param value the value
     * @return <CODE>true</CODE> if the value was inserted,
     * <CODE>false</CODE> if the name is incompatible with
     * an existing field
     */
    public boolean setFieldAsName(String field, String value) {
        return setField(field, new PdfName(value));
    }

    /** Sets the field value as a string.
     * @param field the fully qualified field name
     * @param value the value
     * @return <CODE>true</CODE> if the value was inserted,
     * <CODE>false</CODE> if the name is incompatible with
     * an existing field
     */
    public boolean setFieldAsString(String field, String value) {
        return setField(field, new PdfString(value, PdfObject.TEXT_UNICODE));
    }

    /**
     * Sets the field value as a <CODE>PDFAction</CODE>.
     * For example, this method allows setting a form submit button action using {@link PdfAction#createSubmitForm(String, Object[], int)}.
     * This method creates an <CODE>A</CODE> entry for the specified field in the underlying FDF file.
     * Method contributed by Philippe Laflamme (plaflamme)
     * @param field the fully qualified field name
     * @param action the field's action
     * @return <CODE>true</CODE> if the value was inserted,
     * <CODE>false</CODE> if the name is incompatible with
     * an existing field
     * @since	2.1.5
     */
    public boolean setFieldAsAction(String field, PdfAction action) {
    	return setField(field, action);
    }

    public boolean setFieldAsTemplate(String field, PdfTemplate template) {
        try {
            PdfDictionary d = new PdfDictionary();
            if (template instanceof PdfImportedPage)
                d.put(PdfName.N, template.getIndirectReference());
            else {
                PdfStream str = template.getFormXObject(PdfStream.NO_COMPRESSION);
                PdfIndirectReference ref = wrt.addToBody(str).getIndirectReference();
                d.put(PdfName.N, ref);
            }
            return setField(field, d);
        } catch (Exception e) {
            throw new ExceptionConverter(e);
        }
    }

    public boolean setFieldAsImage(String field, Image image) {
        try {
            if (Float.isNaN(image.getAbsoluteX()))
                image.setAbsolutePosition(0, image.getAbsoluteY());
            if (Float.isNaN(image.getAbsoluteY()))
                image.setAbsolutePosition(image.getAbsoluteY(), 0);
            PdfTemplate tmpl = PdfTemplate.createTemplate(wrt, image.getWidth(), image.getHeight());
            tmpl.addImage(image);
            PdfStream str = tmpl.getFormXObject(PdfStream.NO_COMPRESSION);
            PdfIndirectReference ref = wrt.addToBody(str).getIndirectReference();
            PdfDictionary d = new PdfDictionary();
            d.put(PdfName.N, ref);
            return setField(field, d);
        } catch (Exception de) {
            throw new ExceptionConverter(de);
        }
    }

    public boolean setFieldAsJavascript(String field, PdfName jsTrigName, String js) {
        PdfAnnotation dict = wrt.createAnnotation(null, null);
        PdfAction javascript = PdfAction.javaScript(js, wrt);
        dict.put(jsTrigName, javascript);
        return setField(field, dict);
    }

    public PdfImportedPage getImportedPage(PdfReader reader, int pageNumber) {
        return wrt.getImportedPage(reader, pageNumber);
    }

    public PdfTemplate createTemplate(float width, float height) {
        return PdfTemplate.createTemplate(wrt, width, height);
    }

    /** Sets all the fields from this <CODE>FdfReader</CODE>
     * @param fdf the <CODE>FdfReader</CODE>
     */
    public void setFields(FdfReader fdf) {
        HashMap<String, PdfDictionary> map = fdf.getFields();
        for (Map.Entry<String, PdfDictionary> entry: map.entrySet()) {
            String key = entry.getKey();
            PdfDictionary dic = entry.getValue();
            PdfObject v = dic.get(PdfName.V);
            if (v != null) {
                setField(key, v);
            }
            v = dic.get(PdfName.A); // (plaflamme)
            if (v != null) {
            	setField(key, v);
            }
        }
    }

    /** Sets all the fields from this <CODE>PdfReader</CODE>
     * @param pdf the <CODE>PdfReader</CODE>
     */
    public void setFields(PdfReader pdf) {
        setFields(pdf.getAcroFields());
    }

    /** Sets all the fields from this <CODE>AcroFields</CODE>
     * @param af the <CODE>AcroFields</CODE>
     */
    public void setFields(AcroFields af) {
        for (Map.Entry<String, Item> entry: af.getFields().entrySet()) {
            String fn = entry.getKey();
            AcroFields.Item item = entry.getValue();
            PdfDictionary dic = item.getMerged(0);
            PdfObject v = PdfReader.getPdfObjectRelease(dic.get(PdfName.V));
            if (v == null)
                continue;
            PdfObject ft = PdfReader.getPdfObjectRelease(dic.get(PdfName.FT));
            if (ft == null || PdfName.SIG.equals(ft))
                continue;
            setField(fn, v);
        }
    }

    /** Gets the PDF file name associated with the FDF.
     * @return the PDF file name associated with the FDF
     */
    public String getFile() {
        return this.file;
    }

    /** Sets the PDF file name associated with the FDF.
     * @param file the PDF file name associated with the FDF
     *
     */
    public void setFile(String file) {
        this.file = file;
    }

    static class Wrt extends PdfWriter {
        private FdfWriter fdf;

        Wrt(OutputStream os, FdfWriter fdf) throws IOException {
            super(new PdfDocument(), os);
            this.fdf = fdf;
            this.os.write(HEADER_FDF);
            body = new PdfBody(this);
        }

        void write() throws IOException {
            for (PdfReaderInstance element : readerInstances.values()) {
                currentPdfReaderInstance= element;
                currentPdfReaderInstance.writeAllPages();
            }

            PdfDictionary dic = new PdfDictionary();
            dic.put(PdfName.FIELDS, calculate(fdf.fields));
            if (fdf.file != null)
                dic.put(PdfName.F, new PdfString(fdf.file, PdfObject.TEXT_UNICODE));
            if (fdf.statusMessage != null && fdf.statusMessage.trim().length() != 0)
                dic.put(PdfName.STATUS, new PdfString(fdf.statusMessage));
            PdfDictionary fd = new PdfDictionary();
            fd.put(PdfName.FDF, dic);
            PdfIndirectReference ref = addToBody(fd).getIndirectReference();
            os.write(getISOBytes("trailer\n"));
            PdfDictionary trailer = new PdfDictionary();
            trailer.put(PdfName.ROOT, ref);
            trailer.toPdf(null, os);
            os.write(getISOBytes("\n%%EOF\n"));
            os.close();
        }


        @SuppressWarnings("unchecked")
        PdfArray calculate(HashMap<String, Object> map) throws IOException {
            PdfArray ar = new PdfArray();
            for (Map.Entry<String, Object> entry: map.entrySet()) {
                String key = entry.getKey();
                Object v = entry.getValue();
                PdfDictionary dic = new PdfDictionary();
                dic.put(PdfName.T, new PdfString(key, PdfObject.TEXT_UNICODE));
                if (v instanceof HashMap) {
                    dic.put(PdfName.KIDS, calculate((HashMap<String, Object>)v));
                } else if(v instanceof PdfAction) {	// (plaflamme)
                   	dic.put(PdfName.A, (PdfAction)v);
                } else if (v instanceof PdfAnnotation) {
                    dic.put(PdfName.AA, (PdfAnnotation)v);
                } else if (v instanceof PdfDictionary && ((PdfDictionary)v).size() == 1 && ((PdfDictionary)v).contains(PdfName.N)) {
                    dic.put(PdfName.AP, (PdfDictionary)v);
                } else {
                    dic.put(PdfName.V, (PdfObject)v);
                }
                ar.add(dic);
            }
            return ar;
        }
    }

	protected Counter COUNTER = CounterFactory.getCounter(FdfWriter.class);
	protected Counter getCounter() {
		return COUNTER;
	}
}
