src/scratchpad/src/org/apache/poi/hemf/usermodel/HemfEmbeddedIterator.java

/* ====================================================================
   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.
==================================================================== */

package org.apache.poi.hemf.usermodel;

import java.awt.Transparency;
import java.awt.color.ColorSpace;
import java.awt.image.BufferedImage;
import java.awt.image.ComponentColorModel;
import java.awt.image.DataBuffer;
import java.awt.image.DataBufferByte;
import java.awt.image.PixelInterleavedSampleModel;
import java.awt.image.Raster;
import java.awt.image.WritableRaster;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.ArrayDeque;
import java.util.Deque;
import java.util.Iterator;

import javax.imageio.ImageIO;

import org.apache.poi.hemf.record.emf.HemfComment;
import org.apache.poi.hemf.record.emf.HemfRecord;
import org.apache.poi.hemf.record.emfplus.HemfPlusObject;
import org.apache.poi.hwmf.record.HwmfBitmapDib;
import org.apache.poi.hwmf.record.HwmfFill;
import org.apache.poi.hwmf.usermodel.HwmfEmbedded;
import org.apache.poi.hwmf.usermodel.HwmfEmbeddedType;
import org.apache.poi.poifs.filesystem.FileMagic;

public class HemfEmbeddedIterator implements Iterator<HwmfEmbedded> {

    private final Deque<Iterator<?>> iterStack = new ArrayDeque<>();
    private Object current;

    public HemfEmbeddedIterator(HemfPicture emf) {
        this(emf.getRecords().iterator());
    }

    public HemfEmbeddedIterator(Iterator<HemfRecord> recordIterator) {
        iterStack.add(recordIterator);
    }

    @Override
    public boolean hasNext() {
        if (iterStack.isEmpty()) {
            return false;
        }

        if (current != null) {
            // don't search twice and potentially skip items
            return true;
        }

        Iterator<?> iter;
        do {
            iter = iterStack.peek();
            while (iter.hasNext()) {
                Object obj = iter.next();
                if (obj instanceof HemfComment.EmfComment) {
                    HemfComment.EmfCommentData cd = ((HemfComment.EmfComment)obj).getCommentData();
                    if (
                        cd instanceof HemfComment.EmfCommentDataWMF ||
                        cd instanceof HemfComment.EmfCommentDataGeneric
                    ) {
                        current = obj;
                        return true;
                    }

                    if (cd instanceof HemfComment.EmfCommentDataMultiformats) {
                        Iterator<?> iter2 = ((HemfComment.EmfCommentDataMultiformats)cd).getFormats().iterator();
                        if (iter2.hasNext()) {
                            iterStack.push(iter2);
                            continue;
                        }
                    }

                    if (cd instanceof HemfComment.EmfCommentDataPlus) {
                        Iterator<?> iter2 = ((HemfComment.EmfCommentDataPlus)cd).getRecords().iterator();
                        if (iter2.hasNext()) {
                            iter = iter2;
                            iterStack.push(iter2);
                            continue;
                        }
                    }
                }

                if (obj instanceof HemfComment.EmfCommentDataFormat) {
                    current = obj;
                    return true;
                }

                if (obj instanceof HemfPlusObject.EmfPlusObject && ((HemfPlusObject.EmfPlusObject)obj).getObjectType() == HemfPlusObject.EmfPlusObjectType.IMAGE) {
                    current = obj;
                    return true;
                }

                if (obj instanceof HwmfFill.WmfStretchDib) {
                    HwmfBitmapDib bitmap = ((HwmfFill.WmfStretchDib) obj).getBitmap();
                    if (bitmap.isValid()) {
                        current = obj;
                        return true;
                    }
                }
            }
            iterStack.pop();
        } while (!iterStack.isEmpty());

        return false;
    }

    @Override
    public HwmfEmbedded next() {
        HwmfEmbedded emb;
        if ((emb = checkEmfCommentDataWMF()) != null) {
            return emb;
        }
        if ((emb = checkEmfCommentDataGeneric()) != null) {
            return emb;
        }
        if ((emb = checkEmfCommentDataFormat()) != null) {
            return emb;
        }
        if ((emb = checkEmfPlusObject()) != null) {
            return emb;
        }
        if ((emb = checkWmfStretchDib()) != null) {
            return emb;
        }

        return null;
    }

    private HwmfEmbedded checkEmfCommentDataWMF() {
        if (!(current instanceof HemfComment.EmfCommentDataWMF && ((HemfComment.EmfComment)current).getCommentData() instanceof HemfComment.EmfCommentDataWMF)) {
            return null;
        }

        HemfComment.EmfCommentDataWMF wmf = (HemfComment.EmfCommentDataWMF)((HemfComment.EmfComment)current).getCommentData();
        HwmfEmbedded emb = new HwmfEmbedded();
        emb.setEmbeddedType(HwmfEmbeddedType.WMF);
        emb.setData(wmf.getWMFData());
        current = null;
        return emb;
    }

    private HwmfEmbedded checkEmfCommentDataGeneric() {
        if (!(current instanceof HemfComment.EmfComment && ((HemfComment.EmfComment)current).getCommentData() instanceof HemfComment.EmfCommentDataGeneric)) {
            return null;
        }
        HemfComment.EmfCommentDataGeneric cdg = (HemfComment.EmfCommentDataGeneric)((HemfComment.EmfComment)current).getCommentData();
        HwmfEmbedded emb = new HwmfEmbedded();
        emb.setEmbeddedType(HwmfEmbeddedType.UNKNOWN);
        emb.setData(cdg.getPrivateData());
        current = null;
        return emb;
    }

    private HwmfEmbedded checkEmfCommentDataFormat() {
        if (!(current instanceof HemfComment.EmfCommentDataFormat)) {
            return null;
        }
        HemfComment.EmfCommentDataFormat cdf = (HemfComment.EmfCommentDataFormat)current;
        HwmfEmbedded emb = new HwmfEmbedded();
        boolean isEmf = (cdf.getSignature() == HemfComment.EmfFormatSignature.ENHMETA_SIGNATURE);
        emb.setEmbeddedType(isEmf ? HwmfEmbeddedType.EMF : HwmfEmbeddedType.EPS);
        emb.setData(cdf.getRawData());
        current = null;
        return emb;
    }

    private HwmfEmbedded checkWmfStretchDib() {
        if (!(current instanceof HwmfFill.WmfStretchDib)) {
            return null;
        }
        HwmfEmbedded emb = new HwmfEmbedded();
        emb.setData(((HwmfFill.WmfStretchDib) current).getBitmap().getBMPData());
        emb.setEmbeddedType(HwmfEmbeddedType.BMP);
        current = null;
        return emb;
    }

    private HwmfEmbedded checkEmfPlusObject() {
        if (!(current instanceof HemfPlusObject.EmfPlusObject)) {
            return null;
        }

        HemfPlusObject.EmfPlusObject epo = (HemfPlusObject.EmfPlusObject)current;
        assert(epo.getObjectType() == HemfPlusObject.EmfPlusObjectType.IMAGE);
        HemfPlusObject.EmfPlusImage img = epo.getObjectData();
        assert(img.getImageDataType() != null);

        HwmfEmbedded emb = getEmfPlusImageData();

        HwmfEmbeddedType et;
        switch (img.getImageDataType()) {
            case BITMAP:
                if (img.getBitmapType() == HemfPlusObject.EmfPlusBitmapDataType.COMPRESSED) {
                    switch (FileMagic.valueOf(emb.getRawData())) {
                        case JPEG:
                            et = HwmfEmbeddedType.JPEG;
                            break;
                        case GIF:
                            et = HwmfEmbeddedType.GIF;
                            break;
                        case PNG:
                            et = HwmfEmbeddedType.PNG;
                            break;
                        case TIFF:
                            et = HwmfEmbeddedType.TIFF;
                            break;
                        default:
                            et = HwmfEmbeddedType.BITMAP;
                            break;
                    }
                } else {
                    et = HwmfEmbeddedType.PNG;
                    compressGDIBitmap(img, emb, et);
                }
                break;
            case METAFILE:
                assert(img.getMetafileType() != null);
                switch (img.getMetafileType()) {
                    case Wmf:
                    case WmfPlaceable:
                        et = HwmfEmbeddedType.WMF;
                        break;
                    case Emf:
                    case EmfPlusDual:
                    case EmfPlusOnly:
                        et = HwmfEmbeddedType.EMF;
                        break;
                    default:
                        et = HwmfEmbeddedType.UNKNOWN;
                        break;
                }
                break;
            default:
                et = HwmfEmbeddedType.UNKNOWN;
                break;
        }
        emb.setEmbeddedType(et);

        return emb;
    }

    /**
     * Compress GDIs internal format to something useful
     */
    private void compressGDIBitmap(HemfPlusObject.EmfPlusImage img, HwmfEmbedded emb, HwmfEmbeddedType et) {
        final int width = img.getBitmapWidth();
        final int height = img.getBitmapHeight();
        final int stride = img.getBitmapStride();
        final HemfPlusObject.EmfPlusPixelFormat pf = img.getPixelFormat();

        int[] nBits, bOffs;
        switch (pf) {
            case ARGB_32BPP:
                nBits = new int[]{8, 8, 8, 8};
                bOffs = new int[]{2, 1, 0, 3};
                break;
            case RGB_24BPP:
                nBits = new int[]{8, 8, 8};
                bOffs = new int[]{2, 1, 0};
                break;
            default:
                throw new RuntimeException("not yet implemented");
        }

        ColorSpace cs = ColorSpace.getInstance(ColorSpace.CS_sRGB);
        ComponentColorModel cm = new ComponentColorModel
                (cs, nBits, pf.isAlpha(), pf.isPreMultiplied(), Transparency.TRANSLUCENT, DataBuffer.TYPE_BYTE);
        PixelInterleavedSampleModel csm =
                new PixelInterleavedSampleModel(cm.getTransferType(), width, height, cm.getNumColorComponents(), stride, bOffs);

        byte d[] = emb.getRawData();
        WritableRaster raster = (WritableRaster) Raster.createRaster(csm, new DataBufferByte(d, d.length), null);

        BufferedImage bi = new BufferedImage(cm, raster, cm.isAlphaPremultiplied(), null);

        try {
            ByteArrayOutputStream bos = new ByteArrayOutputStream();
            // use HwmfEmbeddedType literal for conversion
            ImageIO.write(bi, et.toString(), bos);
            emb.setData(bos.toByteArray());
        } catch (IOException e) {
            // TODO: throw appropriate exception
            throw new RuntimeException(e);
        }
    }


    private HwmfEmbedded getEmfPlusImageData() {
        HemfPlusObject.EmfPlusObject epo = (HemfPlusObject.EmfPlusObject)current;
        assert(epo.getObjectType() == HemfPlusObject.EmfPlusObjectType.IMAGE);

        final int objectId = epo.getObjectId();

        HwmfEmbedded emb = new HwmfEmbedded();

        HemfPlusObject.EmfPlusImage img = (HemfPlusObject.EmfPlusImage)epo.getObjectData();
        assert(img.getImageDataType() != null);

        ByteArrayOutputStream bos = new ByteArrayOutputStream();
        try {
            for (;;) {
                bos.write(img.getImageData());

                current = null;
                //noinspection ConstantConditions
                if (hasNext() &&
                    (current instanceof HemfPlusObject.EmfPlusObject) &&
                    ((epo = (HemfPlusObject.EmfPlusObject) current).getObjectId() == objectId)
                ) {
                    img = (HemfPlusObject.EmfPlusImage)epo.getObjectData();
                } else {
                    return emb;
                }
            }
        } catch (IOException e) {
            // ByteArrayOutputStream doesn't throw IOException
            return null;
        } finally {
            emb.setData(bos.toByteArray());
        }
    }
}