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org.jpedal.grouping.PdfGroupingAlgorithms Maven / Gradle / Ivy

/*
 * ===========================================
 * Java Pdf Extraction Decoding Access Library
 * ===========================================
 *
 * Project Info:  http://www.idrsolutions.com
 * Help section for developers at http://www.idrsolutions.com/support/
 *
 * (C) Copyright 1997-2015 IDRsolutions and Contributors.
 *
 * This file is part of JPedal/JPDF2HTML5
 *
     This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA


 *
 * ---------------
 * PdfGroupingAlgorithms.java
 * ---------------
 */
package org.jpedal.grouping;

import java.awt.Rectangle;
import java.util.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.jpedal.color.GenericColorSpace;
import org.jpedal.exception.PdfException;
import org.jpedal.objects.PdfData;
import org.jpedal.objects.PdfPageData;
import org.jpedal.utils.Fonts;
import org.jpedal.utils.LogWriter;
import org.jpedal.utils.Sorts;
import org.jpedal.utils.Strip;
import org.jpedal.utils.repositories.Vector_Float;
import org.jpedal.utils.repositories.Vector_Int;
import org.jpedal.utils.repositories.Vector_Object;
import org.jpedal.utils.repositories.Vector_Rectangle;
import org.jpedal.utils.repositories.Vector_String;
import org.jpedal.utils.repositories.generic.Vector_Rectangle_Int;

/**
 * Applies heuristics to unstructured PDF text to create content
 */
public class PdfGroupingAlgorithms {
    
    private boolean includeHTMLtags;
    
    private static final String SystemSeparator = System.getProperty("line.separator");
    
    //public PdfGroupingAlgorithms() {}
	
	/** ==============START OF ARRAYS================ */
	/**
	 * content is stored in a set of arrays. We have tried various methods (ie
	 * create composite object, etc) and none are entirely satisfactory. The
	 * beauty of this method is speed.
	 */

	/**
	 * flag to show this item has been merged into another and should be
	 * ignored. This allows us to repeat operations on live elements without
	 * lots of deleting.
	 */
	private boolean[] isUsed;

	/** co-ords of object (x1,y1 is top left) */
	private float[] f_x1, f_x2, f_y1, f_y2;
	
	/**track if we removed space from end*/
	private boolean[] hadSpace;
	
	/**hold colour info*/
	private String[] f_colorTag;
	
	/**hold writing mode*/
	private int[] writingMode;
	
	/** font sizes in pixels */
	private int[] fontSize;

	/** amount of space a space uses in this font/size */
	private float[] spaceWidth;

	/** actual text */
	private StringBuilder[] content;

	/** raw number of text characters */
	private int[] textLength;

	/** ==============END OF ARRAYS================ */

    /**
	 * handle on page data object. We extract data from this into local arrays
	 * and return grouped content into object at end. This is done for speed.
	 */
	private final PdfData pdf_data;

	/** flag to show if output for table is CSV or XHTML */
	private boolean isXHTML = true;

	/** slot to insert next value - used when we split fragments for table code */
	private int nextSlot;

	/** vertical breaks for table calculation */
	private Vector_Int lineBreaks = new Vector_Int();

	/** holds details as we scan lines for table */
	private Vector_Object lines;

	/** lookup table used to sort into correct order for table */
	private Vector_Int lineY2;

	/**
	 * marker char used in content (we bury location for each char so we can
	 * split)
	 */
	private static final String MARKER = PdfData.marker;
	public static final char MARKER2= MARKER.charAt(0);

	/** counters for cols and rows and pointer to final object we merge into */
	private int max_rows, master;
	
	/**flag to show color info is being extracted*/
	private boolean colorExtracted;
	
	/** used to calculate correct order for table lines */
	private int[] line_order;

	/** amount we resize arrays holding content with if no space */
    private static final int increment = 100;

	public static boolean useUnrotatedCoords;

	/**flag to show if tease created on findText*/
	private boolean includeTease;

	/**teasers for findtext*/
	private String[] teasers;

	private final List multipleTermTeasers = new ArrayList();

	private boolean usingMultipleTerms;

    private boolean isXMLExtraction=true;

    /*
      * Variables to allow cross line search results
      */
	/**Value placed between result areas to show they are part of the same result*/
	private static final int linkedSearchAreas=-101;
	
	/** create a new instance, passing in raw data */
	public PdfGroupingAlgorithms(final PdfData pdf_data, final PdfPageData pageData, final boolean isXMLExtraction) {
		this.pdf_data = pdf_data;
	this.isXMLExtraction=isXMLExtraction;
		colorExtracted=pdf_data.isColorExtracted();
    }
	
	/**
	 * workout if we should use space, CR or no separator when joining lines
	 */
    private static String getLineDownSeparator(final StringBuilder rawLine1, final StringBuilder rawLine2, final boolean isXMLExtraction) {

		String returnValue = " "; //space is default

		final boolean hasUnderline = false;

		/**get 2 lines without any XML or spaces so we can look at last char*/
        final StringBuilder line1;
        final StringBuilder line2;
        if(isXMLExtraction){
			line1 = Strip.stripXML(rawLine1,isXMLExtraction);
			line2 = Strip.stripXML(rawLine2,isXMLExtraction);
		}else{
			line1 = Strip.trim(rawLine1);
			line2 = Strip.trim(rawLine2);
		}
		
		/**get lengths and if appropriate perform tests*/
		final int line1Len = line1.length();
		final int line2Len = line2.length();
		//System.out.println(line1Len+" "+line2Len);
		if((line1Len>1)&&(line2Len>1)){

			/**get chars to test*/
			final char line1Char2 = line1.charAt(line1Len - 1);
			final char line1Char1 = line1.charAt(line1Len - 2);
			final char line2Char1 = line2.charAt(0);
			final char line2Char2 = line2.charAt(1);

			//deal with hyphenation first - ignore unless :- or space-
            final String hyphen_values = "";
            if (hyphen_values.indexOf(line1Char2) != -1) {
				returnValue = ""; //default of nothing
				if (line1Char1 == ':') {
                    returnValue = "\n";
                }
				if (line1Char2 == ' ') {
                    returnValue = " ";
                }
                //paragraph breaks if full stop and next line has ascii char or Capital Letter
            } else if (
				((line1Char1 == '.') || (line1Char2 == '.'))
					&& (Character.isUpperCase(line2Char1)
						|| (line2Char1 == '&')
						|| Character.isUpperCase(line2Char2)
						|| (line2Char2 == '&'))){
				if(isXMLExtraction) {
                    returnValue = "
\n";
                } else {
                    returnValue="\n";
                }
			}

		}
		
		//add an underline if appropriate
		if (hasUnderline){
			if(isXMLExtraction) {
                returnValue += "
\n";
            } else {
                returnValue += '\n';
            }
		}
		
		return returnValue;
	}

	/**
	 * remove shadows from text created by double printing of text and drowned
	 * items where text inside other text
	 */
	private void cleanupShadowsAndDrownedObjects(final boolean avoidSpaces) {

		//get list of items
		final int[] items = getUnusedFragments();
		final int count = items.length;
		int c, n;
		String separator;
        float diff;
        
        //work through objects and eliminate shadows or roll together overlaps
		for (int p = 0; p < count; p++) {

			//master item
			c = items[p];

			//ignore used items
			if (!isUsed[c]) {

				//work out mid point in text
				float midX = (f_x1[c] + f_x2[c]) / 2;
				float midY = (f_y1[c] + f_y2[c]) / 2;
				
				for (int p2 = p + 1;p2 < count;p2++) {

					//item to test against
					n = items[p2];
                    
                    //Ignore fragments that have been used or have no width
                    if ((f_x1[n] != f_x2[n]) && (!isUsed[n]) && (!isUsed[c])) {

                        float fontDiff = this.fontSize[n] - fontSize[c];
                        if (fontDiff < 0) {
                            fontDiff = -fontDiff;
                        }

                        diff = (f_x2[n] - f_x1[n]) - (f_x2[c] - f_x1[c]);
                        if(diff<0) {
                            diff=-diff;
                        }

                        /** stop spurious matches on overlapping text*/
						if (fontDiff==0 && (midX > f_x1[n])&& (midX < f_x2[n])
							&& (diff< 10)
							&& (midY < f_y1[n])&& (midY > f_y2[n])) {

                            isUsed[n] = true;

                            //pick up drowned text items (item inside another)			
                        } else {

							final boolean a_in_b =
								(f_x1[n] > f_x1[c])&& (f_x2[n] < f_x2[c])
									&& (f_y1[n] < f_y1[c])&& (f_y2[n] > f_y2[c]);
							final boolean b_in_a =
								(f_x1[c] > f_x1[n])&& (f_x2[c] < f_x2[n])
									&& (f_y1[c] < f_y1[n])&& (f_y2[c] > f_y2[n]);

                            //merge together
                            if (a_in_b || b_in_a) {
                                //get order right - bottom y2 underneath
                                if (f_y2[c] > f_y2[n]) {
									separator =getLineDownSeparator(content[c],content[n],isXMLExtraction);
									if((!avoidSpaces)||(separator.indexOf(' ')==-1)){
										merge(c,n,separator,true);
                                    }
                                } else {
									separator =getLineDownSeparator(content[n],content[c],isXMLExtraction);
									if(!avoidSpaces || separator.indexOf(' ')==-1){
										merge(n,c,separator,true);
                                    }
                                }

                                //recalculate as may have changed
                                midX = (f_x1[c] + f_x2[c]) / 2;
                                midY = (f_y1[c] + f_y2[c]) / 2;

                            }
                        }
                    }
				}
			}
		}
	}
	
	/**
	 * general routine to see if we add a space between 2 text fragments
	 */
    private String isGapASpace(final int c, final int l, final float actualGap, final boolean addMultiplespaceXMLTag, final int writingMode) {
		String sep = "";
		float gap;

		//use smaller gap
		final float gapA = spaceWidth[c] * fontSize[c];
		final float gapB = spaceWidth[l] * fontSize[l];

		if (gapA > gapB) {
            gap = gapB;
        } else {
            gap = gapA;
        }

        gap = (actualGap / (gap / 1000));

        //Round values to closest full integer as float -> int conversion rounds down
        if(gap > 0.51f && gap<1) {
            gap = 1;
        }

        final int spaceCount = (int) gap;

		if (spaceCount > 0) {
            sep = " ";
        }

		/** add an XML tag to flag multiple spaces */
		if (spaceCount > 1 && addMultiplespaceXMLTag && writingMode==PdfData.HORIZONTAL_LEFT_TO_RIGHT) {
            sep = " ";
        }

		return sep;
	}

	/**
	 * merge 2 text fragments together and update co-ordinates
	 */
    private void merge(final int m, final int c, final String separator, final boolean moveFont) {
        
			//update co-ords
			if (f_x1[m] > f_x1[c]) {
                f_x1[m] = f_x1[c];
            }
			if (f_y1[m] < f_y1[c]) {
                f_y1[m] = f_y1[c];
            }
			if (f_x2[m] < f_x2[c]) {
                f_x2[m] = f_x2[c];
            }
			if (f_y2[m] > f_y2[c]) {
                f_y2[m] = f_y2[c];
            }

			if(isXMLExtraction){
				String test=Fonts.fe;

				//add color tag if needed and changes
				if(colorExtracted) {
                    test=Fonts.fe+GenericColorSpace.ce;
                }

				//move  if needed and add separator
				if ((moveFont) && (content[m].toString().lastIndexOf(test)!=-1)) {
					final String master = content[m].toString();
					content[m] =new StringBuilder(master.substring(0, master.lastIndexOf(test)));
					content[m].append(separator);
					content[m].append(master.substring(master.lastIndexOf(test)));	
				} else{
					content[m].append(separator);	
				}

                //Only map out space if text length is longer than 1
				if(textLength[c]>1 && content[m].toString().endsWith(" ")){
					content[m].deleteCharAt(content[m].lastIndexOf(" "));
				}
				//use font size of second text (ie at end of merged text)
				fontSize[m] = fontSize[c];
				
				//Remove excess / redundent xml tags
				if((content[c].indexOf("", content[m].lastIndexOf("")+7==content[m].lastIndexOf(">"))){
						content[c].replace(content[c].indexOf("")+1, "");
						content[m].replace(content[m].lastIndexOf(""), content[m].lastIndexOf("")+8, "");
					}

				if((content[c].indexOf("",content[m].lastIndexOf("")+6==content[m].lastIndexOf(">"))){
						content[c].replace(content[c].indexOf("")+1, "");
						content[m].replace(content[m].lastIndexOf(""), content[m].lastIndexOf("")+7, "");
					}
				
				content[m] = content[m].append(content[c]);
				
				//track length of text less all tokens
				textLength[m] += textLength[c];

				//set objects to null to flush and log as used
				isUsed[c] = true;		
				content[c] = null;
			}else{

				//use font size of second text (ie at end of merged text)
				fontSize[m] = fontSize[c];

				//add together
				content[m] = content[m].append(separator).append(content[c]);

				//track length of text less all tokens
				textLength[m] += textLength[c];

				//set objects to null to flush and log as used
				isUsed[c] = true;		
				content[c] = null;
			}
	}
	
	/**
	 * remove width data we may have buried in data
	 */
    private void removeEncoding() {

		// get list of items
		final int[] items = getUnusedFragments();
		int current;

		// work through objects and eliminate shadows or roll together overlaps
        for (final int item : items) {

            // master item
            current = item;

            // ignore used items and remove widths we hid in data
            if (!isUsed[current]) {
                content[current] = removeHiddenMarkers(current);
            }
        }
	}

	/**
	 * put raw data into Arrays for quick merging breakup_fragments shows if we
	 * break on vertical lines and spaces
	 */
    private void copyToArraysPartial(final int minX, final int minY, final int maxX, final int maxY) {

		colorExtracted=pdf_data.isColorExtracted();
		
		final int count = pdf_data.getRawTextElementCount();

		//local lists for faster access
		final boolean[] isUsed = new boolean[count];
		final int[] fontSize = new int[count];
		final int[] writingMode=new int[count];
		final float[] spaceWidth = new float[count];
		final StringBuilder[] content = new StringBuilder[count];
		final int[] textLength = new int[count];

		final float[] f_x1 = new float[count];
		final String[] f_colorTag=new String[count];
		final float[] f_x2 = new float[count];
		final float[] f_y1 = new float[count];
		final float[] f_y2 = new float[count];
		
		//set defaults and calculate dynamic values
		//int text_length;
//		count = count-increment;
        float x1,x2,y1,y2;
		//float last_pt,min,max,pt,linePos,character_spacing;
		//String raw, char_width = "",currentColor;
		//StringBuilder text = new StringBuilder();

		int currentPoint = 0;
		
		//set values
		for (int i = 0; i < count; i++) {
            
			//extract values
			//character_spacing = pdf_data.f_character_spacing[i];
			//raw = pdf_data.contents[i];
			x1 = pdf_data.f_x1[i];
			//currentColor=pdf_data.colorTag[i];
			x2 = pdf_data.f_x2[i];
			y1 = pdf_data.f_y1[i];
			y2 = pdf_data.f_y2[i];
			//text_length = pdf_data.text_length[i];
			final int mode=pdf_data.f_writingMode[i];

			boolean accepted = false;
			float height;
            
            switch (mode) {
                case PdfData.HORIZONTAL_LEFT_TO_RIGHT:
                case PdfData.HORIZONTAL_RIGHT_TO_LEFT:
                    height = y1-y2;
                    if ((((minX < x1 && x1 < maxX) || (minX < x2 && x2 < maxX)) || //Area contains the x1 or x2 coords
                            ((x1 < minX && minX < x2) || (x1 < maxX && maxX < x2)) //Area is within the x1 and x2 coords
                            )
                            && (minY < y2 + (height / 4) && y2 + (height * 0.75) < maxY) //Area also contains atleast 3/4 of the text y coords
                            ) {
                        accepted = true;
                    }
                    break;
                case PdfData.VERTICAL_BOTTOM_TO_TOP:
                case PdfData.VERTICAL_TOP_TO_BOTTOM:
                    height = x2-x1;
                    if ((((minY < y1 && y1 < maxY) || (minY < y2 && y2 < maxY)) || //Area contains the x1 or x2 coords
                            ((y2 < minY && minY < y1) || (y2 < maxY && maxY < y1)) //Area is within the x1 and x2 coords
                            )
                            && (minX < x1 + (height / 4) && x1 + (height * 0.75) < maxX) //Area also contains atleast 3/4 of the text y coords
                            ) {
                        accepted = true;
                    }
                    break;
            }
			//if at least partly in the area, process
			
			
			if(accepted){
                
                content[currentPoint] = new StringBuilder(pdf_data.contents[i]);

				fontSize[currentPoint] = pdf_data.f_end_font_size[i];
				writingMode[currentPoint]=pdf_data.f_writingMode[i];
				f_x1[currentPoint] = pdf_data.f_x1[i];
				f_colorTag[currentPoint]=pdf_data.colorTag[i];
				f_x2[currentPoint] = pdf_data.f_x2[i];
				f_y1[currentPoint] = pdf_data.f_y1[i];
				f_y2[currentPoint] = pdf_data.f_y2[i];
				
				spaceWidth[currentPoint] = pdf_data.space_width[i];
				textLength[currentPoint] = pdf_data.text_length[i];
				
				StringBuilder startTags = new StringBuilder(content[currentPoint].toString().substring(0, content[currentPoint].toString().indexOf(MARKER)));
				final String contentText = content[currentPoint].toString().substring(content[currentPoint].toString().indexOf(MARKER), content[currentPoint].toString().indexOf('<', content[currentPoint].toString().lastIndexOf(MARKER)));
				String endTags = content[currentPoint].toString().substring(content[currentPoint].toString().lastIndexOf(MARKER));
				//Skips last section of text
				endTags = endTags.substring(endTags.indexOf('<'));
				
				final StringTokenizer tokenizer = new StringTokenizer(contentText, MARKER);
				boolean setX1 = true;
				float width = 0;
				
				while(tokenizer.hasMoreTokens()){
					
					String token = tokenizer.nextToken();
					final float xCoord = (Float.parseFloat(token));
					
					token = tokenizer.nextToken();
					width = Float.parseFloat(token);
					
					token = tokenizer.nextToken();
					final String character = token;
					
					if(setX1){
						if ((mode==PdfData.HORIZONTAL_LEFT_TO_RIGHT || mode==PdfData.HORIZONTAL_RIGHT_TO_LEFT)){
							f_x1[currentPoint] = xCoord;
						}else{
							f_y2[currentPoint] = xCoord;
						}
						setX1 = false;
					}
					
					if ((mode==PdfData.HORIZONTAL_LEFT_TO_RIGHT || mode==PdfData.HORIZONTAL_RIGHT_TO_LEFT)){
						f_x2[currentPoint] = xCoord;
					}else{
						f_y1[currentPoint] = xCoord;
					}
					
                    boolean storeValues = false;
					if ((mode==PdfData.HORIZONTAL_LEFT_TO_RIGHT || mode==PdfData.HORIZONTAL_RIGHT_TO_LEFT)){
                        if(minX