/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

/* $Id: PresentationTextObject.java 1779051 2017-01-16 15:57:25Z ssteiner $ */

package org.apache.fop.afp.modca;

import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
import java.util.List;

import org.apache.fop.afp.AFPLineDataInfo;
import org.apache.fop.afp.AFPTextDataInfo;
import org.apache.fop.afp.ptoca.LineDataInfoProducer;
import org.apache.fop.afp.ptoca.PtocaBuilder;
import org.apache.fop.afp.ptoca.PtocaProducer;
import org.apache.fop.afp.ptoca.TextDataInfoProducer;

The Presentation Text object is the data object used in document processing
environments for representing text which has been prepared for presentation.
Text, as used here, means an ordered string of characters, such as graphic
symbols, numbers, and letters, that are suitable for the specific purpose of
representing coherent information. Text which has been prepared for
presentation has been reduced to a primitive form through explicit
specification of the characters and their placement in the presentation
space. Control sequences which designate specific control functions may be
embedded within the text. These functions extend the primitive form by
applying specific characteristics to the text when it is presented. The
collection of the graphic characters and control codes is called Presentation
Text, and the object that contains the Presentation Text is called the
PresentationText object.
 The content for this object can be created using PtocaBuilder. /**
 * The Presentation Text object is the data object used in document processing
 * environments for representing text which has been prepared for presentation.
 * Text, as used here, means an ordered string of characters, such as graphic
 * symbols, numbers, and letters, that are suitable for the specific purpose of
 * representing coherent information. Text which has been prepared for
 * presentation has been reduced to a primitive form through explicit
 * specification of the characters and their placement in the presentation
 * space. Control sequences which designate specific control functions may be
 * embedded within the text. These functions extend the primitive form by
 * applying specific characteristics to the text when it is presented. The
 * collection of the graphic characters and control codes is called Presentation
 * Text, and the object that contains the Presentation Text is called the
 * PresentationText object.
 * <p>
 * The content for this object can be created using {@link PtocaBuilder}.
 */
public class PresentationTextObject extends AbstractNamedAFPObject {

    
The current presentation text data
/**
     * The current presentation text data
     */
    private PresentationTextData currentPresentationTextData;

    
The presentation text data list
/**
     * The presentation text data list
     */
    private List<PresentationTextData> presentationTextDataList;

    private DefaultBuilder builder = new DefaultBuilder();

    
Construct a new PresentationTextObject for the specified name argument,
the name should be an 8 character identifier.
Params:
name – the name of this presentation object/**
     * Construct a new PresentationTextObject for the specified name argument,
     * the name should be an 8 character identifier.
     *
     * @param name the name of this presentation object
     */
    public PresentationTextObject(String name) {
        super(name);
    }

    
Create the presentation text data for the byte array of data.
Params:
textDataInfo – 
           The afp text data
Throws:
UnsupportedEncodingException – thrown if character encoding is not supported/**
     * Create the presentation text data for the byte array of data.
     *
     * @param textDataInfo
     *            The afp text data
     * @throws UnsupportedEncodingException thrown if character encoding is not supported
     */
    public void createTextData(AFPTextDataInfo textDataInfo) throws UnsupportedEncodingException {
        createControlSequences(new TextDataInfoProducer(textDataInfo));
    }

    
Creates a chain of control sequences using a producer.
Params:
producer – the producer
Throws:
UnsupportedEncodingException – thrown if character encoding is not supported/**
     * Creates a chain of control sequences using a producer.
     * @param producer the producer
     * @throws UnsupportedEncodingException thrown if character encoding is not supported
     */
    public boolean createControlSequences(PtocaProducer producer)
                throws UnsupportedEncodingException {
        if (currentPresentationTextData == null) {
            startPresentationTextData();
        }
        try {
            if (getBytesAvailable() != null && getBytesAvailable() < getSize(producer)) {
                return false;
            }
            producer.produce(builder);
        } catch (UnsupportedEncodingException e) {
            endPresentationTextData();
            throw e;
        } catch (IOException ioe) {
            endPresentationTextData();
            handleUnexpectedIOError(ioe);
        }
        return true;
    }

    private int getSize(PtocaProducer producer) throws IOException {
        final ByteArrayOutputStream bos = new ByteArrayOutputStream();
        PtocaBuilder pb = new PtocaBuilder() {
            protected OutputStream getOutputStreamForControlSequence(int length) {
                return bos;
            }
        };
        producer.produce(pb);
        return bos.size();
    }

    private class DefaultBuilder extends PtocaBuilder {
        public Integer getBytesAvailable() {
            if (currentPresentationTextData == null) {
                return null;
            }
            return currentPresentationTextData.getBytesAvailable();
        }

        protected OutputStream getOutputStreamForControlSequence(int length) {
            if (length > currentPresentationTextData.getBytesAvailable()) {
                endPresentationTextData();
                startPresentationTextData();
            }
            return currentPresentationTextData.getOutputStream();
        }
    }

    
Drawing of lines using the starting and ending coordinates, thickness and
orientation arguments.
Params:
lineDataInfo – the line data information./**
     * Drawing of lines using the starting and ending coordinates, thickness and
     * orientation arguments.
     *
     * @param lineDataInfo the line data information.
     */
    public boolean createLineData(AFPLineDataInfo lineDataInfo) {
        try {
            return createControlSequences(new LineDataInfoProducer(lineDataInfo));
        } catch (UnsupportedEncodingException e) {
            handleUnexpectedIOError(e); //Won't happen for lines
        }
        return false;
    }

    
Helper method to mark the start of the presentation text data
/**
     * Helper method to mark the start of the presentation text data
     */
    private void startPresentationTextData() {
        if (presentationTextDataList == null) {
            presentationTextDataList = new java.util.ArrayList<PresentationTextData>();
        }
        if (presentationTextDataList.size() == 0) {
            currentPresentationTextData = new PresentationTextData(true);
        } else {
            currentPresentationTextData = new PresentationTextData();
        }
        presentationTextDataList.add(currentPresentationTextData);
    }

    
Helper method to mark the end of the presentation text data
/**
     * Helper method to mark the end of the presentation text data
     */
    private void endPresentationTextData() {
        this.currentPresentationTextData = null;
    }

    
{@inheritDoc} /** {@inheritDoc} */
    protected void writeStart(OutputStream os) throws IOException {
        byte[] data = new byte[17];
        copySF(data, Type.BEGIN, Category.PRESENTATION_TEXT);
        os.write(data);
    }

    
{@inheritDoc} /** {@inheritDoc} */
    protected void writeContent(OutputStream os) throws IOException {
        writeObjects(this.presentationTextDataList, os);
    }

    
{@inheritDoc} /** {@inheritDoc} */
    protected void writeEnd(OutputStream os) throws IOException {
        byte[] data = new byte[17];
        copySF(data, Type.END, Category.PRESENTATION_TEXT);
        os.write(data);
    }

    
A control sequence is a sequence of bytes that specifies a control
function. A control sequence consists of a control sequence introducer
and zero or more parameters. The control sequence can extend multiple
presentation text data objects, but must eventually be terminated. This
method terminates the control sequence.
/**
     * A control sequence is a sequence of bytes that specifies a control
     * function. A control sequence consists of a control sequence introducer
     * and zero or more parameters. The control sequence can extend multiple
     * presentation text data objects, but must eventually be terminated. This
     * method terminates the control sequence.
     */
    public void endControlSequence() {
        if (currentPresentationTextData == null) {
            startPresentationTextData();
        }
        try {
            builder.endChainedControlSequence();
        } catch (IOException ioe) {
            endPresentationTextData();
            handleUnexpectedIOError(ioe);
            //Should not occur since we're writing to byte arrays
        }
    }

    private void handleUnexpectedIOError(IOException ioe) {
        //"Unexpected" since we're currently dealing with ByteArrayOutputStreams here.
        throw new RuntimeException("Unexpected I/O error: " + ioe.getMessage(), ioe);
    }

    
{@inheritDoc} /** {@inheritDoc} */
    public String toString() {
        if (presentationTextDataList != null) {
            return presentationTextDataList.toString();
        }
        return super.toString();
    }

    public Integer getBytesAvailable() {
        return builder.getBytesAvailable();
    }
}