package org.librecms.assets;


import com.arsdigita.cms.ContentItem;
import com.arsdigita.cms.contentassets.Note;
import com.arsdigita.persistence.DataCollection;
import com.arsdigita.persistence.DataObject;
import com.arsdigita.util.UncheckedWrapperException;
import com.arsdigita.web.WebConfig;

import com.fasterxml.jackson.core.JsonEncoding;
import com.fasterxml.jackson.core.JsonFactory;
import com.fasterxml.jackson.core.JsonGenerator;
import org.libreccm.export.AbstractDomainObjectsExporter;
import org.libreccm.export.IdSequence;
import org.librecms.contentsection.AbstractAttachmentListsExporter;

import java.io.File;
import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.nio.file.Path;
import java.util.ArrayList;
import java.util.List;
import java.util.UUID;

/**
 *
 * @author <a href="mailto:jens.pelzetter@googlemail.com">Jens Pelzetter</a>
 */
public class SideNoteAttachmentsExporter 
extends AbstractDomainObjectsExporter<ContentItem>{

    @Override
    public Class<ContentItem> exportsType() {
        return ContentItem.class;
    }

    @Override
    public String exportsBaseDataObjectType() {
        return ContentItem.BASE_DATA_OBJECT_TYPE;
    }

    @Override
    public String convertsToType() {
        return "org.librecms.contentsection.ItemAttachment";
    }
    
    @Override
    protected boolean includeSubTypes() {
        return true;
    }


    @Override
    protected List<String> exportDomainObject(final ContentItem item,
                                              final Path targetDir) {
        
        final String listUuid = AbstractAttachmentListsExporter
            .generateListUuid(item, "notes");

        final List<String> attachmentsUuids = new ArrayList<>();
        
        final DataCollection noteAttachments = Note.getNotes(item);
        
        long sortKey = 0;
        while(noteAttachments.next()) {
            
            sortKey++;
            final String uuid = exportNoteAttachment(
                noteAttachments.getDataObject(),
                listUuid,
                sortKey,
                targetDir);
        }
        
        return attachmentsUuids;
    }
    
    private String exportNoteAttachment(final DataObject dataObj,
                                         final String listUuid,
                                         final long sortKey,
                                         final Path targetDir) {
        
        final Note note = new Note(dataObj);
        final String noteUuid = generateUuid(note);
        
        final byte[] uuidSource = String.format(
        "%s/notes/%s",
            WebConfig.getInstanceOf().getSiteName(),
            note.getOID().toString())
        .getBytes(StandardCharsets.UTF_8);
        final String uuid = UUID.nameUUIDFromBytes(uuidSource).toString();
        
         final Path targetFilePath = generateTargetFilePath(targetDir, uuid);
        final File targetFile = targetFilePath.toFile();

        final JsonFactory jsonFactory = new JsonFactory();
        try (JsonGenerator jsonGenerator = jsonFactory
            .createGenerator(targetFile, JsonEncoding.UTF8)) {
            
             jsonGenerator.writeStartObject();

            jsonGenerator.writeNumberField("attachmentId",
                                           IdSequence.getInstance().nextId());
            jsonGenerator.writeStringField("uuid", uuid);

            jsonGenerator.writeStringField("attachmentList", listUuid);
            jsonGenerator.writeStringField("asset", noteUuid);

            jsonGenerator.writeNumberField("sortKey", sortKey);

            jsonGenerator.writeEndObject();
            
        } catch(IOException ex) {
            
            throw new UncheckedWrapperException(ex);
        }
        
        return noteUuid;
    }
    
}