/* ====================================================================
   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.extractor;

import java.io.ByteArrayInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.util.Iterator;
import java.util.List;

import org.apache.poi.POIOLE2TextExtractor;
import org.apache.poi.POITextExtractor;
import org.apache.poi.hdgf.extractor.VisioTextExtractor;
import org.apache.poi.hpbf.extractor.PublisherTextExtractor;
import org.apache.poi.hslf.extractor.PowerPointExtractor;
import org.apache.poi.hsmf.MAPIMessage;
import org.apache.poi.hsmf.datatypes.AttachmentChunks;
import org.apache.poi.hsmf.extractor.OutlookTextExtactor;
import org.apache.poi.hwpf.OldWordFileFormatException;
import org.apache.poi.hwpf.extractor.Word6Extractor;
import org.apache.poi.hwpf.extractor.WordExtractor;
import org.apache.poi.poifs.filesystem.DirectoryEntry;
import org.apache.poi.poifs.filesystem.DirectoryNode;
import org.apache.poi.poifs.filesystem.Entry;

/**
 * Scratchpad-specific logic for {@link OLE2ExtractorFactory} and
 *  {@link org.apache.poi.extractor.ExtractorFactory}, which permit the other two to run with
 *  no Scratchpad jar (though without functionality!)
 * <p>Note - should not be used standalone, always use via the other
 *  two classes</p>
 */
@SuppressWarnings("WeakerAccess")
public class OLE2ScratchpadExtractorFactory {
    /**
     * Look for certain entries in the stream, to figure it
     * out what format is desired
     * Note - doesn't check for core-supported formats!
     * Note - doesn't check for OOXML-supported formats
     */
    public static POITextExtractor createExtractor(DirectoryNode poifsDir) throws IOException {
        if (poifsDir.hasEntry("WordDocument")) {
            // Old or new style word document?
            try {
                return new WordExtractor(poifsDir);
            } catch (OldWordFileFormatException e) {
                return new Word6Extractor(poifsDir);
            }
        }

        if (poifsDir.hasEntry("PowerPoint Document")) {
            return new PowerPointExtractor(poifsDir);
        }

        if (poifsDir.hasEntry("VisioDocument")) {
            return new VisioTextExtractor(poifsDir);
        }

        if (poifsDir.hasEntry("Quill")) {
            return new PublisherTextExtractor(poifsDir);
        }

        final String[] outlookEntryNames = new String[] {
                // message bodies, saved as plain text (PtypString)
                // The first short (0x1000, 0x0047, 0x0037) refer to the Property ID (see [MS-OXPROPS].pdf)
                // the second short (0x001e, 0x001f, 0x0102) refer to the type of data stored in this entry
                // https://msdn.microsoft.com/endatatypes.Ex-us/library/cc433490(v=exchg.80).aspx
                // @see org.apache.poi.hsmf.Types.MAPIType
                "__substg1.0_1000001E", //PidTagBody ASCII
                "__substg1.0_1000001F", //PidTagBody Unicode
                "__substg1.0_0047001E", //PidTagMessageSubmissionId ASCII
                "__substg1.0_0047001F", //PidTagMessageSubmissionId Unicode
                "__substg1.0_0037001E", //PidTagSubject ASCII
                "__substg1.0_0037001F", //PidTagSubject Unicode
        };
        for (String entryName : outlookEntryNames) {
            if (poifsDir.hasEntry(entryName)) {
                return new OutlookTextExtactor(poifsDir);
            }
        }

        throw new IllegalArgumentException("No supported documents found in the OLE2 stream");
    }

    /**
     * Returns an array of text extractors, one for each of
     *  the embedded documents in the file (if there are any).
     * If there are no embedded documents, you'll get back an
     *  empty array. Otherwise, you'll get one open
     *  {@link POITextExtractor} for each embedded file.
     */
    public static void identifyEmbeddedResources(POIOLE2TextExtractor ext, List<Entry> dirs, List<InputStream> nonPOIFS) throws IOException {
        // Find all the embedded directories
        DirectoryEntry root = ext.getRoot();
        if (root == null) {
            throw new IllegalStateException("The extractor didn't know which POIFS it came from!");
        }

        if (ext instanceof WordExtractor) {
            // These are in ObjectPool -> _... under the root
            try {
                DirectoryEntry op = (DirectoryEntry)
                        root.getEntry("ObjectPool");
                Iterator<Entry> it = op.getEntries();
                while(it.hasNext()) {
                    Entry entry = it.next();
                    if(entry.getName().startsWith("_")) {
                        dirs.add(entry);
                    }
                }
            } catch(FileNotFoundException e) {
                // ignored here
            }
            //} else if(ext instanceof PowerPointExtractor) {
            // Tricky, not stored directly in poifs
            // TODO
        } else if (ext instanceof OutlookTextExtactor) {
            // Stored in the Attachment blocks
            MAPIMessage msg = ((OutlookTextExtactor)ext).getMAPIMessage();
            for (AttachmentChunks attachment : msg.getAttachmentFiles()) {
                if (attachment.getAttachData() != null) {
                    byte[] data = attachment.getAttachData().getValue();
                    nonPOIFS.add( new ByteArrayInputStream(data) );
                } else if (attachment.getAttachmentDirectory() != null) {
                    dirs.add(attachment.getAttachmentDirectory().getDirectory());
                }
            }
        }
    }
}