# PDDeviceNAttributes.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.pdfbox.pdmodel.graphics.color;

    import org.apache.pdfbox.cos.COSBase;
    import org.apache.pdfbox.cos.COSDictionary;
    import org.apache.pdfbox.cos.COSName;
    import org.apache.pdfbox.pdmodel.common.COSDictionaryMap;

    import java.io.IOException;
    import java.util.HashMap;
    import java.util.Map;

    import org.apache.commons.logging.Log;
    import org.apache.commons.logging.LogFactory;

    /**
     * Contains additional information about the components of colour space.
     * Instead of using the alternate color space and tint transform, conforming readers may use custom
     * blending algorithms, along with other information provided in the attributes dictionary.
     *
     * @author Ben Litchfield
     */
    public final class PDDeviceNAttributes
    {
        /**
         * Log instance.
         */
        private static final Log LOG = LogFactory.getLog(PDDeviceNAttributes.class);

        private final COSDictionary dictionary;

        /**
         * Creates a new DeviceN colour space attributes dictionary.
         */
        public PDDeviceNAttributes()
        {
            dictionary = new COSDictionary();
        }

        /**
         * Creates a new DeviceN colour space attributes dictionary from the given dictionary.
         * @param attributes a dictionary that has all of the attributes
         */
        public PDDeviceNAttributes(COSDictionary attributes)
        {
            dictionary = attributes;
        }

        /**
         * Returns the underlying COS dictionary.
         * @return the dictionary that this object wraps
         */
        public COSDictionary getCOSDictionary()
        {
            return dictionary;
        }

        /**
         * Returns a map of colorants and their associated Separation color space.
         * @return map of colorants to color spaces, never null.
         * @throws IOException If there is an error reading a color space
         */
        public Map<String, PDSeparation> getColorants() throws IOException
        {
            Map<String,PDSeparation> actuals = new HashMap<>();
            COSDictionary colorants = dictionary.getCOSDictionary(COSName.COLORANTS);
            if(colorants == null)
            {
                colorants = new COSDictionary();
                dictionary.setItem(COSName.COLORANTS, colorants);
            }
            else
            {
                for (COSName name : colorants.keySet())
                {
                    COSBase value = colorants.getDictionaryObject(name);
                    actuals.put(name.getName(), (PDSeparation) PDColorSpace.create(value));
                }
            }
            return new COSDictionaryMap<>(actuals, colorants);
        }

        /**
         * Returns the DeviceN Process Dictionary, or null if it is missing.
         * @return the DeviceN Process Dictionary, or null if it is missing.
         */
        public PDDeviceNProcess getProcess()
        {
            COSDictionary process = dictionary.getCOSDictionary(COSName.PROCESS);
            if (process == null)
            {
                return null;
            }
            return new PDDeviceNProcess(process);
        }

        /**
         * Returns true if this is an NChannel (PDF 1.6) color space.
         * @return true if this is an NChannel color space.
         */
        public boolean isNChannel()
        {
            return "NChannel".equals(dictionary.getNameAsString(COSName.SUBTYPE));
        }

        /**
         * Sets the colorant map.
         * @param colorants the map of colorants
         */
        public void setColorants(Map<String, PDColorSpace> colorants)
        {
            COSDictionary colorantDict = null;
            if(colorants != null)
            {
                colorantDict = COSDictionaryMap.convert(colorants);
            }
            dictionary.setItem(COSName.COLORANTS, colorantDict);
        }

        @Override
        public String toString()
        {
            StringBuilder sb = new StringBuilder(dictionary.getNameAsString(COSName.SUBTYPE));
            sb.append('{');
            PDDeviceNProcess process = getProcess();
            if (process != null)
            {
                sb.append(process);
                sb.append(' ');
            }

            Map<String, PDSeparation> colorants;
            try
            {
                colorants = getColorants();
                sb.append("Colorants{");
                for (Map.Entry<String, PDSeparation> col : colorants.entrySet())
                {
                    sb.append('\"');
                    sb.append(col.getKey());
                    sb.append("\": ");
                    sb.append(col.getValue());
                    sb.append(' ');
                }
                sb.append('}');
            }
            catch (IOException e)
            {
                LOG.debug("Couldn't get the colorants information - returning 'ERROR' instead'", e);
                sb.append("ERROR");
            }
            sb.append('}');
            return sb.toString();
        }

    }