PdfPages.java

/*
 * Copyright (C) 2012  Armin Häberling
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>
 */

package com.aha.pdftools.model;

import java.io.File;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class PdfPages extends AbstractModelObject {

    private static final Logger LOGGER = LoggerFactory.getLogger(PdfPages.class);

    private final File mSourceFile;
    private final int mSourcePageCount;
    private List<Integer> mPages;

    public PdfPages(File sourceFile, int sourcePageCount) {
        mSourceFile = sourceFile;
        mSourcePageCount = sourcePageCount;
        mPages = new ArrayList<Integer>(sourcePageCount);
        for (int i = 0; i < sourcePageCount; i++) {
            mPages.add(i + 1);
        }
    }

    public String getSourcePath() {
        return mSourceFile.getAbsolutePath();
    }

    public File getSourceFile() {
        return mSourceFile;
    }

    public String getName() {
        return mSourceFile.getName();
    }

    public List<Integer> getPages() {
        return Collections.unmodifiableList(mPages);
    }

    public int getPageCount() {
        return mPages.size();
    }

    public int getSourcePageCount() {
        return mSourcePageCount;
    }

    public String getPagesString() {
        StringBuilder sb = new StringBuilder();
        Interval interval = null;
        for (int curPage : mPages) {
            if (interval != null) {
                if (!interval.addPage(curPage)) {
                    if (sb.length() > 0) {
                        sb.append(", ");
                    }
                    sb.append(interval);
                    interval = new Interval(curPage);
                }
            } else {
                interval = new Interval(curPage);
            }
        }
        if (interval != null) {
            if (sb.length() > 0) {
                sb.append(", ");
            }
            sb.append(interval);
        }
        return sb.toString();
    }

    public void setPagesString(String pagesAsString) {
        String[] intervals = pagesAsString.split(",");
        List<Integer> pages = new ArrayList<Integer>();
        try {
            for (String intervalAsString : intervals) {
                int minusIndex = intervalAsString.indexOf('-');
                if (minusIndex != -1) {
                    // split and add interval
                    int start = Integer.parseInt(intervalAsString.substring(0, minusIndex).trim());
                    int end = Integer.parseInt(intervalAsString.substring(minusIndex + 1).trim());
                    addInterval(pages, start, end);
                } else {
                    int page = Integer.parseInt(intervalAsString.trim());
                    addInterval(pages, page, page);
                }
            }
            mPages = pages;
        } catch (NumberFormatException e) {
            // do nothing
            LOGGER.warn(e.getMessage(), e);
        }
    }

    private void addInterval(List<Integer> pages, int start, int end) {
        if (start < 1 || start > mSourcePageCount || start > end) {
            throw new IllegalArgumentException();
        }
        if (end < 1 || end > mSourcePageCount) {
            throw new IllegalArgumentException();
        }
        for (int i = start; i <= end; i++) {
            pages.add(i);
        }
    }

    private static class Interval {
        private int start;
        private int end;

        public Interval(int start) {
            this.start = start;
            this.end = start;
        }

        public boolean addPage(int page) {
            if (page == end + 1) {
                end = page;
                return true;
            }
            return false;
        }

        @Override
        public String toString() {
            if (start == end) {
                return Integer.toString(start);
            } else {
                return start + " - " + end;
            }
        }
    }
}