# PDColor.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.COSArray;
    import org.apache.pdfbox.cos.COSName;
    import org.apache.pdfbox.cos.COSNumber;

    import java.io.IOException;
    import java.util.Arrays;

    /**
     * A color value, consisting of one or more color components, or for pattern color spaces,
     * a name and optional color components.
     * Color values are not associated with any given color space.
     *
     * Instances of PDColor are immutable.
     *
     * @author John Hewson
     */
    public final class PDColor
    {
        private final float[] components;
        private final COSName patternName;
        private final PDColorSpace colorSpace;

        /**
         * Creates a PDColor containing the given color value.
         * @param array a COS array containing the color value
         * @param colorSpace color space in which the color value is defined
         */
        public PDColor(COSArray array, PDColorSpace colorSpace)
        {
            if (array.size() > 0 && array.get(array.size() - 1) instanceof COSName)
            {
                // color components (optional), for the color of an uncoloured tiling pattern
                components = new float[array.size() - 1];
                for (int i = 0; i < components.length; i++)
                {
                    components[i] = ((COSNumber)array.get(i)).floatValue();
                }

                // pattern name (required)
                patternName = (COSName)array.get(array.size() - 1);
            }
            else
            {
                // color components only
                components = new float[array.size()];
                for (int i = 0; i < array.size(); i++)
                {
                    components[i] = ((COSNumber)array.get(i)).floatValue();
                }
                patternName = null;
            }
            this.colorSpace = colorSpace;
        }

        /**
         * Creates a PDColor containing the given color component values.
         * @param components array of color component values
         * @param colorSpace color space in which the components are defined
         */
        public PDColor(float[] components, PDColorSpace colorSpace)
        {
            this.components = components.clone();
            this.patternName = null;
            this.colorSpace = colorSpace;
        }

        /**
         * Creates a PDColor containing the given pattern name.
         * @param patternName the name of a pattern in a pattern dictionary
         * @param colorSpace color space in which the pattern is defined
         */
        public PDColor(COSName patternName, PDColorSpace colorSpace)
        {
            this.components = new float[0];
            this.patternName = patternName;
            this.colorSpace = colorSpace;
        }

        /**
         * Creates a PDColor containing the given color component values and pattern name.
         * @param components array of color component values
         * @param patternName the name of a pattern in a pattern dictionary
         * @param colorSpace color space in which the pattern/components are defined
         */
        public PDColor(float[] components, COSName patternName, PDColorSpace colorSpace)
        {
            this.components = components.clone();
            this.patternName = patternName;
            this.colorSpace = colorSpace;
        }

        /**
         * Returns the components of this color value.
         * @return the components of this color value, never null.
         */
        public float[] getComponents()
        {
            if (colorSpace instanceof PDPattern || colorSpace == null)
            {
                // colorspace of the pattern color isn't known, so just clone
                // null colorspace can happen with empty annotation color
                // see PDFBOX-3351-538928-p4.pdf
                return components.clone();
            }
            // PDFBOX-4279: copyOf instead of clone in case array is too small
            return Arrays.copyOf(components, colorSpace.getNumberOfComponents());
        }

        /**
         * Returns the pattern name from this color value.
         * @return the pattern name from this color value
         */
        public COSName getPatternName()
        {
            return patternName;
        }

        /**
         * Returns true if this color value is a pattern.
         * @return true if this color value is a pattern
         */
        public boolean isPattern()
        {
            return patternName != null;
        }

        /**
         * Returns the packed RGB value for this color, if any.
         * @return RGB
         * @throws IOException if the color conversion fails
         * @throws IllegalStateException if this color value is a pattern.
         */
        public int toRGB() throws IOException
        {
            float[] floats = colorSpace.toRGB(components);
            int r = Math.round(floats[0] * 255);
            int g = Math.round(floats[1] * 255);
            int b = Math.round(floats[2] * 255);
            int rgb = r;
            rgb = (rgb << 8) + g;
            rgb = (rgb << 8) + b;
            return rgb;
        }

        /**
         * Returns the color component values as a COS array
         * @return the color component values as a COS array
         */
        public COSArray toCOSArray()
        {
            COSArray array = new COSArray();
            array.setFloatArray(components);
            if (patternName != null)
            {
                array.add(patternName);
            }
            return array;
        }

        /**
         * Returns the color space in which this color value is defined.
         */
        public PDColorSpace getColorSpace()
        {
            return colorSpace;
        }

        @Override
        public String toString()
        {
            return "PDColor{components=" + Arrays.toString(components) + ", patternName=" + patternName + ", colorSpace=" + colorSpace + '}';
        }
    }