# PDSquigglyAppearanceHandler.java

    /*
     * Copyright 2018 The Apache Software Foundation.
     *
     * Licensed 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.interactive.annotation.handlers;

    import java.awt.geom.AffineTransform;
    import java.io.IOException;
    import org.apache.commons.logging.Log;
    import org.apache.commons.logging.LogFactory;
    import org.apache.pdfbox.cos.COSName;
    import org.apache.pdfbox.pdmodel.PDAppearanceContentStream;
    import org.apache.pdfbox.pdmodel.PDDocument;
    import org.apache.pdfbox.pdmodel.PDFormContentStream;
    import org.apache.pdfbox.pdmodel.PDPatternContentStream;
    import org.apache.pdfbox.pdmodel.PDResources;
    import org.apache.pdfbox.pdmodel.common.PDRectangle;
    import org.apache.pdfbox.pdmodel.graphics.color.PDColor;
    import org.apache.pdfbox.pdmodel.graphics.color.PDColorSpace;
    import org.apache.pdfbox.pdmodel.graphics.color.PDDeviceRGB;
    import org.apache.pdfbox.pdmodel.graphics.color.PDPattern;
    import org.apache.pdfbox.pdmodel.graphics.form.PDFormXObject;
    import org.apache.pdfbox.pdmodel.graphics.pattern.PDTilingPattern;
    import org.apache.pdfbox.pdmodel.interactive.annotation.PDAnnotation;
    import org.apache.pdfbox.pdmodel.interactive.annotation.PDAnnotationSquiggly;
    import org.apache.pdfbox.util.Matrix;

    /**
     *
     */
    public class PDSquigglyAppearanceHandler extends PDAbstractAppearanceHandler
    {
        private static final Log LOG = LogFactory.getLog(PDSquigglyAppearanceHandler.class);

        public PDSquigglyAppearanceHandler(PDAnnotation annotation)
        {
            super(annotation);
        }

        public PDSquigglyAppearanceHandler(PDAnnotation annotation, PDDocument document)
        {
            super(annotation, document);
        }

        @Override
        public void generateNormalAppearance()
        {
            PDAnnotationSquiggly annotation = (PDAnnotationSquiggly) getAnnotation();
            PDRectangle rect = annotation.getRectangle();
            if (rect == null)
            {
                return;
            }
            float[] pathsArray = annotation.getQuadPoints();
            if (pathsArray == null)
            {
                return;
            }
            AnnotationBorder ab = AnnotationBorder.getAnnotationBorder(annotation, annotation.getBorderStyle());
            PDColor color = annotation.getColor();
            if (color == null || color.getComponents().length == 0)
            {
                return;
            }
            if (Float.compare(ab.width, 0) == 0)
            {
                // value found in adobe reader
                ab.width = 1.5f;
            }

            // Adjust rectangle even if not empty, see PLPDF.com-MarkupAnnotations.pdf
            //TODO in a class structure this should be overridable
            // this is similar to polyline but different data type
            // all coordinates (unlike painting) are used because I'm lazy
            float minX = Float.MAX_VALUE;
            float minY = Float.MAX_VALUE;
            float maxX = Float.MIN_VALUE;
            float maxY = Float.MIN_VALUE;
            for (int i = 0; i < pathsArray.length / 2; ++i)
            {
                float x = pathsArray[i * 2];
                float y = pathsArray[i * 2 + 1];
                minX = Math.min(minX, x);
                minY = Math.min(minY, y);
                maxX = Math.max(maxX, x);
                maxY = Math.max(maxY, y);
            }
            rect.setLowerLeftX(Math.min(minX - ab.width / 2, rect.getLowerLeftX()));
            rect.setLowerLeftY(Math.min(minY - ab.width / 2, rect.getLowerLeftY()));
            rect.setUpperRightX(Math.max(maxX + ab.width / 2, rect.getUpperRightX()));
            rect.setUpperRightY(Math.max(maxY + ab.width / 2, rect.getUpperRightY()));
            annotation.setRectangle(rect);

            try (PDAppearanceContentStream cs = getNormalAppearanceAsContentStream())
            {
                setOpacity(cs, annotation.getConstantOpacity());

                cs.setStrokingColor(color);

                //TODO we ignore dash pattern and line width for now. Do they have any effect?

                // quadpoints spec is incorrect
                // https://stackoverflow.com/questions/9855814/pdf-spec-vs-acrobat-creation-quadpoints
                for (int i = 0; i < pathsArray.length / 8; ++i)
                {
                    // Adobe uses a fixed pattern that assumes a height of 40, and it transforms to that height
                    // horizontally and the same / 1.8 vertically.
                    // translation apparently based on bottom left, but slightly different in Adobe
                    //TODO what if the annotation is not horizontal?
                    float height = pathsArray[i * 8 + 1] - pathsArray[i * 8 + 5];
                    cs.transform(new Matrix(height / 40f, 0, 0, height / 40f / 1.8f, pathsArray[i * 8 + 4], pathsArray[i * 8 + 5]));

                    // Create form, BBox is mostly fixed, except for the horizontal size which is
                    // horizontal size divided by the horizontal transform factor from above
                    // (almost)
                    PDFormXObject form = new PDFormXObject(createCOSStream());
                    form.setBBox(new PDRectangle(-0.5f, -0.5f, (pathsArray[i * 8 + 2] - pathsArray[i * 8]) / height * 40f + 0.5f, 13));
                    form.setResources(new PDResources());
                    form.setMatrix(AffineTransform.getTranslateInstance(0.5f, 0.5f));
                    cs.drawForm(form);
                    try (PDFormContentStream formCS = new PDFormContentStream(form))
                    {
                        PDTilingPattern pattern = new PDTilingPattern();
                        pattern.setBBox(new PDRectangle(0, 0, 10, 12));
                        pattern.setXStep(10);
                        pattern.setYStep(13);
                        pattern.setTilingType(PDTilingPattern.TILING_CONSTANT_SPACING_FASTER_TILING);
                        pattern.setPaintType(PDTilingPattern.PAINT_UNCOLORED);
                        try (PDPatternContentStream patternCS = new PDPatternContentStream(pattern))
                        {
                            // from Adobe
                            patternCS.setLineCapStyle(1);
                            patternCS.setLineJoinStyle(1);
                            patternCS.setLineWidth(1);
                            patternCS.setMiterLimit(10);
                            patternCS.moveTo(0, 1);
                            patternCS.lineTo(5, 11);
                            patternCS.lineTo(10, 1);
                            patternCS.stroke();
                        }
                        COSName patternName = form.getResources().add(pattern);
                        PDColorSpace patternColorSpace = new PDPattern(null, PDDeviceRGB.INSTANCE);
                        PDColor patternColor = new PDColor(color.getComponents(), patternName, patternColorSpace);
                        formCS.setNonStrokingColor(patternColor);

                        // With Adobe, the horizontal size is slightly different, don't know why
                        formCS.addRect(0, 0, (pathsArray[i * 8 + 2] - pathsArray[i * 8]) / height * 40f, 12);
                        formCS.fill();
                    }
                }
            }
            catch (IOException ex)
            {
                LOG.error(ex);
            }
        }

        @Override
        public void generateRolloverAppearance()
        {
            // No rollover appearance generated
        }

        @Override
        public void generateDownAppearance()
        {
            // No down appearance generated
        }
    }